diff --git a/dist/shell.c b/dist/shell.c
index 9c21103..eceb780 100644
--- a/dist/shell.c
+++ b/dist/shell.c
@@ -403,6 +403,7 @@
 struct callback_data {
   sqlite3 *db;           /* The database */
   int echoOn;            /* True to echo input commands */
+  int statsOn;           /* True to display memory stats before each finalize */
   int cnt;               /* Number of records displayed so far */
   FILE *out;             /* Write results here */
   int mode;              /* An output mode setting */
@@ -967,6 +968,86 @@
 }
 
 /*
+** Display memory stats.
+*/
+static int display_stats(
+  sqlite3 *db,                /* Database to query */
+  struct callback_data *pArg, /* Pointer to struct callback_data */
+  int bReset                  /* True to reset the stats */
+){
+  int iCur;
+  int iHiwtr;
+
+  if( pArg && pArg->out ){
+    
+    iHiwtr = iCur = -1;
+    sqlite3_status(SQLITE_STATUS_MEMORY_USED, &iCur, &iHiwtr, bReset);
+    fprintf(pArg->out, "Memory Used:                         %d (max %d) bytes\n", iCur, iHiwtr);
+    iHiwtr = iCur = -1;
+    sqlite3_status(SQLITE_STATUS_MALLOC_COUNT, &iCur, &iHiwtr, bReset);
+    fprintf(pArg->out, "Number of Allocations:               %d (max %d)\n", iCur, iHiwtr);
+/*
+** Not currently used by the CLI.
+**    iHiwtr = iCur = -1;
+**    sqlite3_status(SQLITE_STATUS_PAGECACHE_USED, &iCur, &iHiwtr, bReset);
+**    fprintf(pArg->out, "Number of Pcache Pages Used:         %d (max %d) pages\n", iCur, iHiwtr);
+*/
+    iHiwtr = iCur = -1;
+    sqlite3_status(SQLITE_STATUS_PAGECACHE_OVERFLOW, &iCur, &iHiwtr, bReset);
+    fprintf(pArg->out, "Number of Pcache Overflow Bytes:     %d (max %d) bytes\n", iCur, iHiwtr);
+/*
+** Not currently used by the CLI.
+**    iHiwtr = iCur = -1;
+**    sqlite3_status(SQLITE_STATUS_SCRATCH_USED, &iCur, &iHiwtr, bReset);
+**    fprintf(pArg->out, "Number of Scratch Allocations Used:  %d (max %d)\n", iCur, iHiwtr);
+*/
+    iHiwtr = iCur = -1;
+    sqlite3_status(SQLITE_STATUS_SCRATCH_OVERFLOW, &iCur, &iHiwtr, bReset);
+    fprintf(pArg->out, "Number of Scratch Overflow Bytes:    %d (max %d) bytes\n", iCur, iHiwtr);
+    iHiwtr = iCur = -1;
+    sqlite3_status(SQLITE_STATUS_MALLOC_SIZE, &iCur, &iHiwtr, bReset);
+    fprintf(pArg->out, "Largest Allocation:                  %d bytes\n", iHiwtr);
+    iHiwtr = iCur = -1;
+    sqlite3_status(SQLITE_STATUS_PAGECACHE_SIZE, &iCur, &iHiwtr, bReset);
+    fprintf(pArg->out, "Largest Pcache Allocation:           %d bytes\n", iHiwtr);
+    iHiwtr = iCur = -1;
+    sqlite3_status(SQLITE_STATUS_SCRATCH_SIZE, &iCur, &iHiwtr, bReset);
+    fprintf(pArg->out, "Largest Scratch Allocation:          %d bytes\n", iHiwtr);
+#ifdef YYTRACKMAXSTACKDEPTH
+    iHiwtr = iCur = -1;
+    sqlite3_status(SQLITE_STATUS_PARSER_STACK, &iCur, &iHiwtr, bReset);
+    fprintf(pArg->out, "Deepest Parser Stack:                %d (max %d)\n", iCur, iHiwtr);
+#endif
+  }
+
+  if( pArg && pArg->out && db ){
+    iHiwtr = iCur = -1;
+    sqlite3_db_status(db, SQLITE_DBSTATUS_LOOKASIDE_USED, &iCur, &iHiwtr, bReset);
+    fprintf(pArg->out, "Lookaside Slots Used:                %d (max %d)\n", iCur, iHiwtr);
+    iHiwtr = iCur = -1;
+    sqlite3_db_status(db, SQLITE_DBSTATUS_CACHE_USED, &iCur, &iHiwtr, bReset);
+    fprintf(pArg->out, "Pager Heap Usage:                    %d bytes\n", iCur); 
+    iHiwtr = iCur = -1;
+    sqlite3_db_status(db, SQLITE_DBSTATUS_SCHEMA_USED, &iCur, &iHiwtr, bReset);
+    fprintf(pArg->out, "Schema Heap Usage:                   %d bytes\n", iCur); 
+    iHiwtr = iCur = -1;
+    sqlite3_db_status(db, SQLITE_DBSTATUS_STMT_USED, &iCur, &iHiwtr, bReset);
+    fprintf(pArg->out, "Statement Heap/Lookaside Usage:      %d bytes\n", iCur); 
+  }
+
+  if( pArg && pArg->out && db && pArg->pStmt ){
+    iCur = sqlite3_stmt_status(pArg->pStmt, SQLITE_STMTSTATUS_FULLSCAN_STEP, bReset);
+    fprintf(pArg->out, "Fullscan Steps:                      %d\n", iCur);
+    iCur = sqlite3_stmt_status(pArg->pStmt, SQLITE_STMTSTATUS_SORT, bReset);
+    fprintf(pArg->out, "Sort Operations:                     %d\n", iCur);
+    iCur = sqlite3_stmt_status(pArg->pStmt, SQLITE_STMTSTATUS_AUTOINDEX, bReset);
+    fprintf(pArg->out, "Autoindex Inserts:                   %d\n", iCur);
+  }
+
+  return 0;
+}
+
+/*
 ** Execute a statement or set of statements.  Print 
 ** any result rows/columns depending on the current mode 
 ** set via the supplied callback.
@@ -1005,10 +1086,16 @@
         continue;
       }
 
+      /* save off the prepared statment handle and reset row count */
+      if( pArg ){
+        pArg->pStmt = pStmt;
+        pArg->cnt = 0;
+      }
+
       /* echo the sql statement if echo on */
-      if( pArg->echoOn ){
+      if( pArg && pArg->echoOn ){
         const char *zStmtSql = sqlite3_sql(pStmt);
-        fprintf(pArg->out,"%s\n", zStmtSql ? zStmtSql : zSql);
+        fprintf(pArg->out, "%s\n", zStmtSql ? zStmtSql : zSql);
       }
 
       /* perform the first step.  this will tell us if we
@@ -1034,11 +1121,6 @@
             for(i=0; i<nCol; i++){
               azCols[i] = (char *)sqlite3_column_name(pStmt, i);
             }
-            /* save off the prepared statment handle and reset row count */
-            if( pArg ){
-              pArg->pStmt = pStmt;
-              pArg->cnt = 0;
-            }
             do{
               /* extract the data and data types */
               for(i=0; i<nCol; i++){
@@ -1061,9 +1143,6 @@
               }
             } while( SQLITE_ROW == rc );
             sqlite3_free(pData);
-            if( pArg ){
-              pArg->pStmt = NULL;
-            }
           }
         }else{
           do{
@@ -1072,6 +1151,11 @@
         }
       }
 
+      /* print usage stats if stats on */
+      if( pArg && pArg->statsOn ){
+        display_stats(db, pArg, 0);
+      }
+
       /* Finalize the statement just executed. If this fails, save a 
       ** copy of the error message. Otherwise, set zSql to point to the
       ** next statement to execute. */
@@ -1082,6 +1166,11 @@
       }else if( pzErrMsg ){
         *pzErrMsg = save_err_msg(db);
       }
+
+      /* clear saved stmt handle */
+      if( pArg ){
+        pArg->pStmt = NULL;
+      }
     }
   } /* end while */
 
@@ -1261,6 +1350,7 @@
   "                         LIKE pattern TABLE.\n"
   ".separator STRING      Change separator used by output mode and .import\n"
   ".show                  Show the current values for various settings\n"
+  ".stats ON|OFF          Turn stats on or off\n"
   ".tables ?TABLE?        List names of tables\n"
   "                         If TABLE specified, only list tables matching\n"
   "                         LIKE pattern TABLE.\n"
@@ -2020,6 +2110,7 @@
     fprintf(p->out,"%9.9s: ", "separator");
       output_c_string(p->out, p->separator);
       fprintf(p->out, "\n");
+    fprintf(p->out,"%9.9s: %s\n","stats", p->statsOn ? "on" : "off");
     fprintf(p->out,"%9.9s: ","width");
     for (i=0;i<(int)ArraySize(p->colWidth) && p->colWidth[i] != 0;i++) {
       fprintf(p->out,"%d ",p->colWidth[i]);
@@ -2027,6 +2118,10 @@
     fprintf(p->out,"\n");
   }else
 
+  if( c=='s' && strncmp(azArg[0], "stats", n)==0 && nArg>1 && nArg<3 ){
+    p->statsOn = booleanValue(azArg[1]);
+  }else
+
   if( c=='t' && n>1 && strncmp(azArg[0], "tables", n)==0 && nArg<3 ){
     char **azResult;
     int nRow;
@@ -2410,6 +2505,7 @@
   "   -line                set output mode to 'line'\n"
   "   -list                set output mode to 'list'\n"
   "   -separator 'x'       set output field separator (|)\n"
+  "   -stats               print memory stats before each finalize\n"
   "   -nullvalue 'text'    set text string for NULL values\n"
   "   -version             show SQLite version\n"
 ;
@@ -2574,6 +2670,8 @@
       data.showHeader = 0;
     }else if( strcmp(z,"-echo")==0 ){
       data.echoOn = 1;
+    }else if( strcmp(z,"-stats")==0 ){
+      data.statsOn = 1;
     }else if( strcmp(z,"-bail")==0 ){
       bail_on_error = 1;
     }else if( strcmp(z,"-version")==0 ){
diff --git a/dist/shell.c.orig b/dist/shell.c.orig
index 23099b9..c5aa40c 100644
--- a/dist/shell.c.orig
+++ b/dist/shell.c.orig
@@ -398,6 +398,7 @@
 struct callback_data {
   sqlite3 *db;           /* The database */
   int echoOn;            /* True to echo input commands */
+  int statsOn;           /* True to display memory stats before each finalize */
   int cnt;               /* Number of records displayed so far */
   FILE *out;             /* Write results here */
   int mode;              /* An output mode setting */
@@ -962,6 +963,86 @@
 }
 
 /*
+** Display memory stats.
+*/
+static int display_stats(
+  sqlite3 *db,                /* Database to query */
+  struct callback_data *pArg, /* Pointer to struct callback_data */
+  int bReset                  /* True to reset the stats */
+){
+  int iCur;
+  int iHiwtr;
+
+  if( pArg && pArg->out ){
+    
+    iHiwtr = iCur = -1;
+    sqlite3_status(SQLITE_STATUS_MEMORY_USED, &iCur, &iHiwtr, bReset);
+    fprintf(pArg->out, "Memory Used:                         %d (max %d) bytes\n", iCur, iHiwtr);
+    iHiwtr = iCur = -1;
+    sqlite3_status(SQLITE_STATUS_MALLOC_COUNT, &iCur, &iHiwtr, bReset);
+    fprintf(pArg->out, "Number of Allocations:               %d (max %d)\n", iCur, iHiwtr);
+/*
+** Not currently used by the CLI.
+**    iHiwtr = iCur = -1;
+**    sqlite3_status(SQLITE_STATUS_PAGECACHE_USED, &iCur, &iHiwtr, bReset);
+**    fprintf(pArg->out, "Number of Pcache Pages Used:         %d (max %d) pages\n", iCur, iHiwtr);
+*/
+    iHiwtr = iCur = -1;
+    sqlite3_status(SQLITE_STATUS_PAGECACHE_OVERFLOW, &iCur, &iHiwtr, bReset);
+    fprintf(pArg->out, "Number of Pcache Overflow Bytes:     %d (max %d) bytes\n", iCur, iHiwtr);
+/*
+** Not currently used by the CLI.
+**    iHiwtr = iCur = -1;
+**    sqlite3_status(SQLITE_STATUS_SCRATCH_USED, &iCur, &iHiwtr, bReset);
+**    fprintf(pArg->out, "Number of Scratch Allocations Used:  %d (max %d)\n", iCur, iHiwtr);
+*/
+    iHiwtr = iCur = -1;
+    sqlite3_status(SQLITE_STATUS_SCRATCH_OVERFLOW, &iCur, &iHiwtr, bReset);
+    fprintf(pArg->out, "Number of Scratch Overflow Bytes:    %d (max %d) bytes\n", iCur, iHiwtr);
+    iHiwtr = iCur = -1;
+    sqlite3_status(SQLITE_STATUS_MALLOC_SIZE, &iCur, &iHiwtr, bReset);
+    fprintf(pArg->out, "Largest Allocation:                  %d bytes\n", iHiwtr);
+    iHiwtr = iCur = -1;
+    sqlite3_status(SQLITE_STATUS_PAGECACHE_SIZE, &iCur, &iHiwtr, bReset);
+    fprintf(pArg->out, "Largest Pcache Allocation:           %d bytes\n", iHiwtr);
+    iHiwtr = iCur = -1;
+    sqlite3_status(SQLITE_STATUS_SCRATCH_SIZE, &iCur, &iHiwtr, bReset);
+    fprintf(pArg->out, "Largest Scratch Allocation:          %d bytes\n", iHiwtr);
+#ifdef YYTRACKMAXSTACKDEPTH
+    iHiwtr = iCur = -1;
+    sqlite3_status(SQLITE_STATUS_PARSER_STACK, &iCur, &iHiwtr, bReset);
+    fprintf(pArg->out, "Deepest Parser Stack:                %d (max %d)\n", iCur, iHiwtr);
+#endif
+  }
+
+  if( pArg && pArg->out && db ){
+    iHiwtr = iCur = -1;
+    sqlite3_db_status(db, SQLITE_DBSTATUS_LOOKASIDE_USED, &iCur, &iHiwtr, bReset);
+    fprintf(pArg->out, "Lookaside Slots Used:                %d (max %d)\n", iCur, iHiwtr);
+    iHiwtr = iCur = -1;
+    sqlite3_db_status(db, SQLITE_DBSTATUS_CACHE_USED, &iCur, &iHiwtr, bReset);
+    fprintf(pArg->out, "Pager Heap Usage:                    %d bytes\n", iCur); 
+    iHiwtr = iCur = -1;
+    sqlite3_db_status(db, SQLITE_DBSTATUS_SCHEMA_USED, &iCur, &iHiwtr, bReset);
+    fprintf(pArg->out, "Schema Heap Usage:                   %d bytes\n", iCur); 
+    iHiwtr = iCur = -1;
+    sqlite3_db_status(db, SQLITE_DBSTATUS_STMT_USED, &iCur, &iHiwtr, bReset);
+    fprintf(pArg->out, "Statement Heap/Lookaside Usage:      %d bytes\n", iCur); 
+  }
+
+  if( pArg && pArg->out && db && pArg->pStmt ){
+    iCur = sqlite3_stmt_status(pArg->pStmt, SQLITE_STMTSTATUS_FULLSCAN_STEP, bReset);
+    fprintf(pArg->out, "Fullscan Steps:                      %d\n", iCur);
+    iCur = sqlite3_stmt_status(pArg->pStmt, SQLITE_STMTSTATUS_SORT, bReset);
+    fprintf(pArg->out, "Sort Operations:                     %d\n", iCur);
+    iCur = sqlite3_stmt_status(pArg->pStmt, SQLITE_STMTSTATUS_AUTOINDEX, bReset);
+    fprintf(pArg->out, "Autoindex Inserts:                   %d\n", iCur);
+  }
+
+  return 0;
+}
+
+/*
 ** Execute a statement or set of statements.  Print 
 ** any result rows/columns depending on the current mode 
 ** set via the supplied callback.
@@ -1000,10 +1081,16 @@
         continue;
       }
 
+      /* save off the prepared statment handle and reset row count */
+      if( pArg ){
+        pArg->pStmt = pStmt;
+        pArg->cnt = 0;
+      }
+
       /* echo the sql statement if echo on */
-      if( pArg->echoOn ){
+      if( pArg && pArg->echoOn ){
         const char *zStmtSql = sqlite3_sql(pStmt);
-        fprintf(pArg->out,"%s\n", zStmtSql ? zStmtSql : zSql);
+        fprintf(pArg->out, "%s\n", zStmtSql ? zStmtSql : zSql);
       }
 
       /* perform the first step.  this will tell us if we
@@ -1029,11 +1116,6 @@
             for(i=0; i<nCol; i++){
               azCols[i] = (char *)sqlite3_column_name(pStmt, i);
             }
-            /* save off the prepared statment handle and reset row count */
-            if( pArg ){
-              pArg->pStmt = pStmt;
-              pArg->cnt = 0;
-            }
             do{
               /* extract the data and data types */
               for(i=0; i<nCol; i++){
@@ -1056,9 +1138,6 @@
               }
             } while( SQLITE_ROW == rc );
             sqlite3_free(pData);
-            if( pArg ){
-              pArg->pStmt = NULL;
-            }
           }
         }else{
           do{
@@ -1067,6 +1146,11 @@
         }
       }
 
+      /* print usage stats if stats on */
+      if( pArg && pArg->statsOn ){
+        display_stats(db, pArg, 0);
+      }
+
       /* Finalize the statement just executed. If this fails, save a 
       ** copy of the error message. Otherwise, set zSql to point to the
       ** next statement to execute. */
@@ -1077,6 +1161,11 @@
       }else if( pzErrMsg ){
         *pzErrMsg = save_err_msg(db);
       }
+
+      /* clear saved stmt handle */
+      if( pArg ){
+        pArg->pStmt = NULL;
+      }
     }
   } /* end while */
 
@@ -1256,6 +1345,7 @@
   "                         LIKE pattern TABLE.\n"
   ".separator STRING      Change separator used by output mode and .import\n"
   ".show                  Show the current values for various settings\n"
+  ".stats ON|OFF          Turn stats on or off\n"
   ".tables ?TABLE?        List names of tables\n"
   "                         If TABLE specified, only list tables matching\n"
   "                         LIKE pattern TABLE.\n"
@@ -2001,6 +2091,7 @@
     fprintf(p->out,"%9.9s: ", "separator");
       output_c_string(p->out, p->separator);
       fprintf(p->out, "\n");
+    fprintf(p->out,"%9.9s: %s\n","stats", p->statsOn ? "on" : "off");
     fprintf(p->out,"%9.9s: ","width");
     for (i=0;i<(int)ArraySize(p->colWidth) && p->colWidth[i] != 0;i++) {
       fprintf(p->out,"%d ",p->colWidth[i]);
@@ -2008,6 +2099,10 @@
     fprintf(p->out,"\n");
   }else
 
+  if( c=='s' && strncmp(azArg[0], "stats", n)==0 && nArg>1 && nArg<3 ){
+    p->statsOn = booleanValue(azArg[1]);
+  }else
+
   if( c=='t' && n>1 && strncmp(azArg[0], "tables", n)==0 && nArg<3 ){
     char **azResult;
     int nRow;
@@ -2391,6 +2486,7 @@
   "   -line                set output mode to 'line'\n"
   "   -list                set output mode to 'list'\n"
   "   -separator 'x'       set output field separator (|)\n"
+  "   -stats               print memory stats before each finalize\n"
   "   -nullvalue 'text'    set text string for NULL values\n"
   "   -version             show SQLite version\n"
 ;
@@ -2555,6 +2651,8 @@
       data.showHeader = 0;
     }else if( strcmp(z,"-echo")==0 ){
       data.echoOn = 1;
+    }else if( strcmp(z,"-stats")==0 ){
+      data.statsOn = 1;
     }else if( strcmp(z,"-bail")==0 ){
       bail_on_error = 1;
     }else if( strcmp(z,"-version")==0 ){
diff --git a/dist/sqlite3.c b/dist/sqlite3.c
index c5953e0..f274f6e 100644
--- a/dist/sqlite3.c
+++ b/dist/sqlite3.c
@@ -1,6 +1,6 @@
 /******************************************************************************
 ** This file is an amalgamation of many separate C source files from SQLite
-** version 3.7.0.  By combining all the individual C code files into this 
+** version 3.7.3.  By combining all the individual C code files into this 
 ** single large file, the entire code can be compiled as a one translation
 ** unit.  This allows many compilers to do optimizations that would not be
 ** possible if the files were compiled separately.  Performance improvements
@@ -219,20 +219,21 @@
 # define SQLITE_MAX_VARIABLE_NUMBER 999
 #endif
 
-/* Maximum page size.  The upper bound on this value is 32768.  This a limit
-** imposed by the necessity of storing the value in a 2-byte unsigned integer
-** and the fact that the page size must be a power of 2.
+/* Maximum page size.  The upper bound on this value is 65536.  This a limit
+** imposed by the use of 16-bit offsets within each page.
 **
-** If this limit is changed, then the compiled library is technically
-** incompatible with an SQLite library compiled with a different limit. If
-** a process operating on a database with a page-size of 65536 bytes 
-** crashes, then an instance of SQLite compiled with the default page-size 
-** limit will not be able to rollback the aborted transaction. This could
-** lead to database corruption.
+** Earlier versions of SQLite allowed the user to change this value at
+** compile time. This is no longer permitted, on the grounds that it creates
+** a library that is technically incompatible with an SQLite library 
+** compiled with a different limit. If a process operating on a database 
+** with a page-size of 65536 bytes crashes, then an instance of SQLite 
+** compiled with the default page-size limit will not be able to rollback 
+** the aborted transaction. This could lead to database corruption.
 */
-#ifndef SQLITE_MAX_PAGE_SIZE
-# define SQLITE_MAX_PAGE_SIZE 32768
+#ifdef SQLITE_MAX_PAGE_SIZE
+# undef SQLITE_MAX_PAGE_SIZE
 #endif
+#define SQLITE_MAX_PAGE_SIZE 65536
 
 
 /*
@@ -357,15 +358,21 @@
 #endif
 
 /*
-** The SQLITE_THREADSAFE macro must be defined as either 0 or 1.
+** The SQLITE_THREADSAFE macro must be defined as 0, 1, or 2.
+** 0 means mutexes are permanently disable and the library is never
+** threadsafe.  1 means the library is serialized which is the highest
+** level of threadsafety.  2 means the libary is multithreaded - multiple
+** threads can use SQLite as long as no two threads try to use the same
+** database connection at the same time.
+**
 ** Older versions of SQLite used an optional THREADSAFE macro.
-** We support that for legacy
+** We support that for legacy.
 */
 #if !defined(SQLITE_THREADSAFE)
 #if defined(THREADSAFE)
 # define SQLITE_THREADSAFE THREADSAFE
 #else
-# define SQLITE_THREADSAFE 1
+# define SQLITE_THREADSAFE 1 /* IMP: R-07272-22309 */
 #endif
 #endif
 
@@ -520,7 +527,7 @@
 ** to fit in 32-bits.  This macro is used inside of various testcase()
 ** macros to verify that we have tested SQLite for large-file support.
 */
-#define IS_BIG_INT(X)  (((X)&(i64)0xffffffff)!=0)
+#define IS_BIG_INT(X)  (((X)&~(i64)0xffffffff)!=0)
 
 /*
 ** The macro unlikely() is a hint that surrounds a boolean
@@ -637,7 +644,7 @@
 **
 ** Since version 3.6.18, SQLite source code has been stored in the
 ** <a href="http://www.fossil-scm.org/">Fossil configuration management
-** system</a>.  ^The SQLITE_SOURCE_ID macro evalutes to
+** system</a>.  ^The SQLITE_SOURCE_ID macro evaluates to
 ** a string which identifies a particular check-in of SQLite
 ** within its configuration management system.  ^The SQLITE_SOURCE_ID
 ** string contains the date and time of the check-in (UTC) and an SHA1
@@ -647,9 +654,9 @@
 ** [sqlite3_libversion_number()], [sqlite3_sourceid()],
 ** [sqlite_version()] and [sqlite_source_id()].
 */
-#define SQLITE_VERSION        "3.7.0"
-#define SQLITE_VERSION_NUMBER 3007000
-#define SQLITE_SOURCE_ID      "2010-07-07 14:45:41 8eefc287265443ec043bdab629597e79c9d22006"
+#define SQLITE_VERSION        "3.7.3"
+#define SQLITE_VERSION_NUMBER 3007003
+#define SQLITE_SOURCE_ID      "2010-09-28 07:24:50 88108fff672b6012ffe87ba4b1efe6d5a07037d1"
 
 /*
 ** CAPI3REF: Run-Time Library Version Numbers
@@ -694,7 +701,7 @@
 ** compile time.  ^The SQLITE_ prefix may be omitted from the 
 ** option name passed to sqlite3_compileoption_used().  
 **
-** ^The sqlite3_compileoption_get() function allows interating
+** ^The sqlite3_compileoption_get() function allows iterating
 ** over the list of options that were defined at compile time by
 ** returning the N-th compile time option string.  ^If N is out of range,
 ** sqlite3_compileoption_get() returns a NULL pointer.  ^The SQLITE_ 
@@ -702,7 +709,7 @@
 ** sqlite3_compileoption_get().
 **
 ** ^Support for the diagnostic functions sqlite3_compileoption_used()
-** and sqlite3_compileoption_get() may be omitted by specifing the 
+** and sqlite3_compileoption_get() may be omitted by specifying the 
 ** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
 **
 ** See also: SQL functions [sqlite_compileoption_used()] and
@@ -808,7 +815,7 @@
 **
 ** ^The sqlite3_close() routine is the destructor for the [sqlite3] object.
 ** ^Calls to sqlite3_close() return SQLITE_OK if the [sqlite3] object is
-** successfullly destroyed and all associated resources are deallocated.
+** successfully destroyed and all associated resources are deallocated.
 **
 ** Applications must [sqlite3_finalize | finalize] all [prepared statements]
 ** and [sqlite3_blob_close | close] all [BLOB handles] associated with
@@ -945,7 +952,9 @@
 #define SQLITE_FORMAT      24   /* Auxiliary database format error */
 #define SQLITE_RANGE       25   /* 2nd parameter to sqlite3_bind out of range */
 #define SQLITE_NOTADB      26   /* File opened that is not a database file */
+// Begin Android Add
 #define SQLITE_UNCLOSED    27   /* db can't be closed due unfinalized stmts */
+// End Android Add
 #define SQLITE_ROW         100  /* sqlite3_step() has another row ready */
 #define SQLITE_DONE        101  /* sqlite3_step() has finished executing */
 /* end-of-error-codes */
@@ -1022,11 +1031,12 @@
 #define SQLITE_OPEN_FULLMUTEX        0x00010000  /* Ok for sqlite3_open_v2() */
 #define SQLITE_OPEN_SHAREDCACHE      0x00020000  /* Ok for sqlite3_open_v2() */
 #define SQLITE_OPEN_PRIVATECACHE     0x00040000  /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_WAL              0x00080000  /* VFS only */
 
 /*
 ** CAPI3REF: Device Characteristics
 **
-** The xDeviceCapabilities method of the [sqlite3_io_methods]
+** The xDeviceCharacteristics method of the [sqlite3_io_methods]
 ** object returns an integer which is a vector of the these
 ** bit values expressing I/O characteristics of the mass storage
 ** device that holds the file that the [sqlite3_io_methods]
@@ -1206,11 +1216,10 @@
   int (*xSectorSize)(sqlite3_file*);
   int (*xDeviceCharacteristics)(sqlite3_file*);
   /* Methods above are valid for version 1 */
-  int (*xShmOpen)(sqlite3_file*);
+  int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
   int (*xShmLock)(sqlite3_file*, int offset, int n, int flags);
-  int (*xShmMap)(sqlite3_file*, int iPage, int pgsz, int, void volatile**);
   void (*xShmBarrier)(sqlite3_file*);
-  int (*xShmClose)(sqlite3_file*, int deleteFlag);
+  int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
   /* Methods above are valid for version 2 */
   /* Additional methods may be added in future releases */
 };
@@ -1236,12 +1245,21 @@
 ** is often close.  The underlying VFS might choose to preallocate database
 ** file space based on this hint in order to help writes to the database
 ** file run faster.
+**
+** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
+** extends and truncates the database file in chunks of a size specified
+** by the user. The fourth argument to [sqlite3_file_control()] should 
+** point to an integer (type int) containing the new chunk-size to use
+** for the nominated database. Allocating database file space in large
+** chunks (say 1MB at a time), may reduce file-system fragmentation and
+** improve performance on some systems.
 */
 #define SQLITE_FCNTL_LOCKSTATE        1
 #define SQLITE_GET_LOCKPROXYFILE      2
 #define SQLITE_SET_LOCKPROXYFILE      3
 #define SQLITE_LAST_ERRNO             4
 #define SQLITE_FCNTL_SIZE_HINT        5
+#define SQLITE_FCNTL_CHUNK_SIZE       6
 
 /*
 ** CAPI3REF: Mutex Handle
@@ -1289,15 +1307,19 @@
 ** The zName field holds the name of the VFS module.  The name must
 ** be unique across all VFS modules.
 **
-** SQLite will guarantee that the zFilename parameter to xOpen
+** ^SQLite guarantees that the zFilename parameter to xOpen
 ** is either a NULL pointer or string obtained
-** from xFullPathname().  SQLite further guarantees that
+** from xFullPathname() with an optional suffix added.
+** ^If a suffix is added to the zFilename parameter, it will
+** consist of a single "-" character followed by no more than
+** 10 alphanumeric and/or "-" characters.
+** ^SQLite further guarantees that
 ** the string will be valid and unchanged until xClose() is
 ** called. Because of the previous sentence,
 ** the [sqlite3_file] can safely store a pointer to the
 ** filename if it needs to remember the filename for some reason.
-** If the zFilename parameter is xOpen is a NULL pointer then xOpen
-** must invent its own temporary name for the file.  Whenever the 
+** If the zFilename parameter to xOpen is a NULL pointer then xOpen
+** must invent its own temporary name for the file.  ^Whenever the 
 ** xFilename parameter is NULL it will also be the case that the
 ** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
 **
@@ -1308,7 +1330,7 @@
 ** If xOpen() opens a file read-only then it sets *pOutFlags to
 ** include [SQLITE_OPEN_READONLY].  Other bits in *pOutFlags may be set.
 **
-** SQLite will also add one of the following flags to the xOpen()
+** ^(SQLite will also add one of the following flags to the xOpen()
 ** call, depending on the object being opened:
 **
 ** <ul>
@@ -1319,7 +1341,8 @@
 ** <li>  [SQLITE_OPEN_TRANSIENT_DB]
 ** <li>  [SQLITE_OPEN_SUBJOURNAL]
 ** <li>  [SQLITE_OPEN_MASTER_JOURNAL]
-** </ul>
+** <li>  [SQLITE_OPEN_WAL]
+** </ul>)^
 **
 ** The file I/O implementation can use the object type flags to
 ** change the way it deals with files.  For example, an application
@@ -1338,10 +1361,11 @@
 ** </ul>
 **
 ** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
-** deleted when it is closed.  The [SQLITE_OPEN_DELETEONCLOSE]
-** will be set for TEMP  databases, journals and for subjournals.
+** deleted when it is closed.  ^The [SQLITE_OPEN_DELETEONCLOSE]
+** will be set for TEMP databases and their journals, transient
+** databases, and subjournals.
 **
-** The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
+** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
 ** with the [SQLITE_OPEN_CREATE] flag, which are both directly
 ** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
 ** API.  The SQLITE_OPEN_EXCLUSIVE flag, when paired with the 
@@ -1350,7 +1374,7 @@
 ** It is <i>not</i> used to indicate the file should be opened 
 ** for exclusive access.
 **
-** At least szOsFile bytes of memory are allocated by SQLite
+** ^At least szOsFile bytes of memory are allocated by SQLite
 ** to hold the  [sqlite3_file] structure passed as the third
 ** argument to xOpen.  The xOpen method does not have to
 ** allocate the structure; it should just fill it in.  Note that
@@ -1360,13 +1384,13 @@
 ** element will be valid after xOpen returns regardless of the success
 ** or failure of the xOpen call.
 **
-** The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
+** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
 ** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
 ** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
 ** to test whether a file is at least readable.   The file can be a
 ** directory.
 **
-** SQLite will always allocate at least mxPathname+1 bytes for the
+** ^SQLite will always allocate at least mxPathname+1 bytes for the
 ** output buffer xFullPathname.  The exact size of the output buffer
 ** is also passed as a parameter to both  methods. If the output buffer
 ** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
@@ -1380,10 +1404,10 @@
 ** of good-quality randomness into zOut.  The return value is
 ** the actual number of bytes of randomness obtained.
 ** The xSleep() method causes the calling thread to sleep for at
-** least the number of microseconds given.  The xCurrentTime()
+** least the number of microseconds given.  ^The xCurrentTime()
 ** method returns a Julian Day Number for the current date and time as
 ** a floating point value.
-** The xCurrentTimeInt64() method returns, as an integer, the Julian
+** ^The xCurrentTimeInt64() method returns, as an integer, the Julian
 ** Day Number multipled by 86400000 (the number of milliseconds in 
 ** a 24-hour day).  
 ** ^SQLite will use the xCurrentTimeInt64() method to get the current
@@ -1433,13 +1457,20 @@
 ** With SQLITE_ACCESS_EXISTS, the xAccess method
 ** simply checks whether the file exists.
 ** With SQLITE_ACCESS_READWRITE, the xAccess method
-** checks whether the file is both readable and writable.
+** checks whether the named directory is both readable and writable
+** (in other words, if files can be added, removed, and renamed within
+** the directory).
+** The SQLITE_ACCESS_READWRITE constant is currently used only by the
+** [temp_store_directory pragma], though this could change in a future
+** release of SQLite.
 ** With SQLITE_ACCESS_READ, the xAccess method
-** checks whether the file is readable.
+** checks whether the file is readable.  The SQLITE_ACCESS_READ constant is
+** currently unused, though it might be used in a future release of
+** SQLite.
 */
 #define SQLITE_ACCESS_EXISTS    0
-#define SQLITE_ACCESS_READWRITE 1
-#define SQLITE_ACCESS_READ      2
+#define SQLITE_ACCESS_READWRITE 1   /* Used by PRAGMA temp_store_directory */
+#define SQLITE_ACCESS_READ      2   /* Unused */
 
 /*
 ** CAPI3REF: Flags for the xShmLock VFS method
@@ -1773,7 +1804,7 @@
 **   <ul>
 **   <li> [sqlite3_memory_used()]
 **   <li> [sqlite3_memory_highwater()]
-**   <li> [sqlite3_soft_heap_limit()]
+**   <li> [sqlite3_soft_heap_limit64()]
 **   <li> [sqlite3_status()]
 **   </ul>)^
 ** ^Memory allocation statistics are enabled by default unless SQLite is
@@ -1787,15 +1818,14 @@
 ** aligned memory buffer from which the scrach allocations will be
 ** drawn, the size of each scratch allocation (sz),
 ** and the maximum number of scratch allocations (N).  The sz
-** argument must be a multiple of 16. The sz parameter should be a few bytes
-** larger than the actual scratch space required due to internal overhead.
+** argument must be a multiple of 16.
 ** The first argument must be a pointer to an 8-byte aligned buffer
 ** of at least sz*N bytes of memory.
-** ^SQLite will use no more than one scratch buffer per thread.  So
-** N should be set to the expected maximum number of threads.  ^SQLite will
-** never require a scratch buffer that is more than 6 times the database
-** page size. ^If SQLite needs needs additional scratch memory beyond 
-** what is provided by this configuration option, then 
+** ^SQLite will use no more than two scratch buffers per thread.  So
+** N should be set to twice the expected maximum number of threads.
+** ^SQLite will never require a scratch buffer that is more than 6
+** times the database page size. ^If SQLite needs needs additional
+** scratch memory beyond what is provided by this configuration option, then 
 ** [sqlite3_malloc()] will be used to obtain the memory needed.</dd>
 **
 ** <dt>SQLITE_CONFIG_PAGECACHE</dt>
@@ -1815,8 +1845,7 @@
 ** memory needs for the first N pages that it adds to cache.  ^If additional
 ** page cache memory is needed beyond what is provided by this option, then
 ** SQLite goes to [sqlite3_malloc()] for the additional storage space.
-** ^The implementation might use one or more of the N buffers to hold 
-** memory accounting information. The pointer in the first argument must
+** The pointer in the first argument must
 ** be aligned to an 8-byte boundary or subsequent behavior of SQLite
 ** will be undefined.</dd>
 **
@@ -1945,8 +1974,14 @@
 ** or equal to the product of the second and third arguments.  The buffer
 ** must be aligned to an 8-byte boundary.  ^If the second argument to
 ** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally
-** rounded down to the next smaller
-** multiple of 8.  See also: [SQLITE_CONFIG_LOOKASIDE]</dd>
+** rounded down to the next smaller multiple of 8.  ^(The lookaside memory
+** configuration for a database connection can only be changed when that
+** connection is not currently using lookaside memory, or in other words
+** when the "current value" returned by
+** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero.
+** Any attempt to change the lookaside memory configuration when lookaside
+** memory is in use leaves the configuration unchanged and returns 
+** [SQLITE_BUSY].)^</dd>
 **
 ** </dl>
 */
@@ -2467,7 +2502,9 @@
 ** is not freed.
 **
 ** ^The memory returned by sqlite3_malloc() and sqlite3_realloc()
-** is always aligned to at least an 8 byte boundary.
+** is always aligned to at least an 8 byte boundary, or to a
+** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time
+** option is used.
 **
 ** In SQLite version 3.5.0 and 3.5.1, it was possible to define
 ** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
@@ -2710,7 +2747,13 @@
 ** ^The callback function registered by sqlite3_profile() is invoked
 ** as each SQL statement finishes.  ^The profile callback contains
 ** the original statement text and an estimate of wall-clock time
-** of how long that statement took to run.
+** of how long that statement took to run.  ^The profile callback
+** time is in units of nanoseconds, however the current implementation
+** is only capable of millisecond resolution so the six least significant
+** digits in the time are meaningless.  Future versions of SQLite
+** might provide greater resolution on the profiler callback.  The
+** sqlite3_profile() function is considered experimental and is
+** subject to change in future versions of SQLite.
 */
 SQLITE_API void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
 SQLITE_API SQLITE_EXPERIMENTAL void *sqlite3_profile(sqlite3*,
@@ -2719,17 +2762,28 @@
 /*
 ** CAPI3REF: Query Progress Callbacks
 **
-** ^This routine configures a callback function - the
-** progress callback - that is invoked periodically during long
-** running calls to [sqlite3_exec()], [sqlite3_step()] and
-** [sqlite3_get_table()].  An example use for this
+** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback
+** function X to be invoked periodically during long running calls to
+** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for
+** database connection D.  An example use for this
 ** interface is to keep a GUI updated during a large query.
 **
+** ^The parameter P is passed through as the only parameter to the 
+** callback function X.  ^The parameter N is the number of 
+** [virtual machine instructions] that are evaluated between successive
+** invocations of the callback X.
+**
+** ^Only a single progress handler may be defined at one time per
+** [database connection]; setting a new progress handler cancels the
+** old one.  ^Setting parameter X to NULL disables the progress handler.
+** ^The progress handler is also disabled by setting N to a value less
+** than 1.
+**
 ** ^If the progress callback returns non-zero, the operation is
 ** interrupted.  This feature can be used to implement a
 ** "Cancel" button on a GUI progress dialog box.
 **
-** The progress handler must not do anything that will modify
+** The progress handler callback must not do anything that will modify
 ** the database connection that invoked the progress handler.
 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
 ** database connections for the meaning of "modify" in this paragraph.
@@ -2788,7 +2842,7 @@
 ** If the 3rd parameter to sqlite3_open_v2() is not one of the
 ** combinations shown above or one of the combinations shown above combined
 ** with the [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX],
-** [SQLITE_OPEN_SHAREDCACHE] and/or [SQLITE_OPEN_SHAREDCACHE] flags,
+** [SQLITE_OPEN_SHAREDCACHE] and/or [SQLITE_OPEN_PRIVATECACHE] flags,
 ** then the behavior is undefined.
 **
 ** ^If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection
@@ -2913,17 +2967,22 @@
 ** [database connection] whose limit is to be set or queried.  The
 ** second parameter is one of the [limit categories] that define a
 ** class of constructs to be size limited.  The third parameter is the
-** new limit for that construct.  The function returns the old limit.)^
+** new limit for that construct.)^
 **
 ** ^If the new limit is a negative number, the limit is unchanged.
-** ^(For the limit category of SQLITE_LIMIT_XYZ there is a 
+** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a 
 ** [limits | hard upper bound]
-** set by a compile-time C preprocessor macro named 
-** [limits | SQLITE_MAX_XYZ].
+** set at compile-time by a C preprocessor macro called
+** [limits | SQLITE_MAX_<i>NAME</i>].
 ** (The "_LIMIT_" in the name is changed to "_MAX_".))^
 ** ^Attempts to increase a limit above its hard upper bound are
 ** silently truncated to the hard upper bound.
 **
+** ^Regardless of whether or not the limit was changed, the 
+** [sqlite3_limit()] interface returns the prior value of the limit.
+** ^Hence, to find the current value of a limit without changing it,
+** simply invoke this interface with the third parameter set to -1.
+**
 ** Run-time limits are intended for use in applications that manage
 ** both their own internal database and also databases that are controlled
 ** by untrusted external sources.  An example application might be a
@@ -2952,7 +3011,7 @@
 **
 ** <dl>
 ** ^(<dt>SQLITE_LIMIT_LENGTH</dt>
-** <dd>The maximum size of any string or BLOB or table row.<dd>)^
+** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^
 **
 ** ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt>
 ** <dd>The maximum length of an SQL statement, in bytes.</dd>)^
@@ -2970,7 +3029,9 @@
 **
 ** ^(<dt>SQLITE_LIMIT_VDBE_OP</dt>
 ** <dd>The maximum number of instructions in a virtual machine program
-** used to implement an SQL statement.</dd>)^
+** used to implement an SQL statement.  This limit is not currently
+** enforced, though that might be added in some future release of
+** SQLite.</dd>)^
 **
 ** ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
 ** <dd>The maximum number of arguments on a function.</dd>)^
@@ -2983,8 +3044,7 @@
 ** [GLOB] operators.</dd>)^
 **
 ** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
-** <dd>The maximum number of variables in an SQL statement that can
-** be bound.</dd>)^
+** <dd>The maximum index number of any [parameter] in an SQL statement.)^
 **
 ** ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
 ** <dd>The maximum depth of recursion for triggers.</dd>)^
@@ -3056,12 +3116,7 @@
 ** <li>
 ** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
 ** always used to do, [sqlite3_step()] will automatically recompile the SQL
-** statement and try to run it again.  ^If the schema has changed in
-** a way that makes the statement no longer valid, [sqlite3_step()] will still
-** return [SQLITE_SCHEMA].  But unlike the legacy behavior, [SQLITE_SCHEMA] is
-** now a fatal error.  Calling [sqlite3_prepare_v2()] again will not make the
-** error go away.  Note: use [sqlite3_errmsg()] to find the text
-** of the parsing error that results in an [SQLITE_SCHEMA] return.
+** statement and try to run it again.
 ** </li>
 **
 ** <li>
@@ -3074,11 +3129,16 @@
 ** </li>
 **
 ** <li>
-** ^If the value of a [parameter | host parameter] in the WHERE clause might
-** change the query plan for a statement, then the statement may be
-** automatically recompiled (as if there had been a schema change) on the first 
-** [sqlite3_step()] call following any change to the 
-** [sqlite3_bind_text | bindings] of the [parameter]. 
+** ^If the specific value bound to [parameter | host parameter] in the 
+** WHERE clause might influence the choice of query plan for a statement,
+** then the statement will be automatically recompiled, as if there had been 
+** a schema change, on the first  [sqlite3_step()] call following any change
+** to the [sqlite3_bind_text | bindings] of that [parameter]. 
+** ^The specific value of WHERE-clause [parameter] might influence the 
+** choice of query plan if the parameter is the left-hand side of a [LIKE]
+** or [GLOB] operator or if the parameter is compared to an indexed column
+** and the [SQLITE_ENABLE_STAT2] compile-time option is enabled.
+** the 
 ** </li>
 ** </ol>
 */
@@ -3145,7 +3205,7 @@
 ** then there is no distinction between protected and unprotected
 ** sqlite3_value objects and they can be used interchangeably.  However,
 ** for maximum code portability it is recommended that applications
-** still make the distinction between between protected and unprotected
+** still make the distinction between protected and unprotected
 ** sqlite3_value objects even when not strictly required.
 **
 ** ^The sqlite3_value objects that are passed as parameters into the
@@ -3191,7 +3251,7 @@
 ** </ul>
 **
 ** In the templates above, NNN represents an integer literal,
-** and VVV represents an alphanumeric identifer.)^  ^The values of these
+** and VVV represents an alphanumeric identifier.)^  ^The values of these
 ** parameters (also called "host parameter names" or "SQL parameters")
 ** can be set using the sqlite3_bind_*() routines defined here.
 **
@@ -3340,6 +3400,8 @@
 ** ^Return the number of columns in the result set returned by the
 ** [prepared statement]. ^This routine returns 0 if pStmt is an SQL
 ** statement that does not return data (for example an [UPDATE]).
+**
+** See also: [sqlite3_data_count()]
 */
 SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);
 
@@ -3530,8 +3592,14 @@
 /*
 ** CAPI3REF: Number of columns in a result set
 **
-** ^The sqlite3_data_count(P) the number of columns in the
-** of the result set of [prepared statement] P.
+** ^The sqlite3_data_count(P) interface returns the number of columns in the
+** current row of the result set of [prepared statement] P.
+** ^If prepared statement P does not have results ready to return
+** (via calls to the [sqlite3_column_int | sqlite3_column_*()] of
+** interfaces) then sqlite3_data_count(P) returns 0.
+** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.
+**
+** See also: [sqlite3_column_count()]
 */
 SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
 
@@ -3611,18 +3679,26 @@
 ** ^If the result is a numeric value then sqlite3_column_bytes() uses
 ** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
 ** the number of bytes in that string.
-** ^The value returned does not include the zero terminator at the end
-** of the string.  ^For clarity: the value returned is the number of
+** ^If the result is NULL, then sqlite3_column_bytes() returns zero.
+**
+** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16()
+** routine returns the number of bytes in that BLOB or string.
+** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts
+** the string to UTF-16 and then returns the number of bytes.
+** ^If the result is a numeric value then sqlite3_column_bytes16() uses
+** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns
+** the number of bytes in that string.
+** ^If the result is NULL, then sqlite3_column_bytes16() returns zero.
+**
+** ^The values returned by [sqlite3_column_bytes()] and 
+** [sqlite3_column_bytes16()] do not include the zero terminators at the end
+** of the string.  ^For clarity: the values returned by
+** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of
 ** bytes in the string, not the number of characters.
 **
 ** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
 ** even empty strings, are always zero terminated.  ^The return
-** value from sqlite3_column_blob() for a zero-length BLOB is an arbitrary
-** pointer, possibly even a NULL pointer.
-**
-** ^The sqlite3_column_bytes16() routine is similar to sqlite3_column_bytes()
-** but leaves the result in UTF-16 in native byte order instead of UTF-8.
-** ^The zero terminator is not included in this count.
+** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.
 **
 ** ^The object returned by [sqlite3_column_value()] is an
 ** [unprotected sqlite3_value] object.  An unprotected sqlite3_value object
@@ -3667,10 +3743,10 @@
 ** used in the table for brevity and because they are familiar to most
 ** C programmers.
 **
-** ^Note that when type conversions occur, pointers returned by prior
+** Note that when type conversions occur, pointers returned by prior
 ** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
 ** sqlite3_column_text16() may be invalidated.
-** ^(Type conversions and pointer invalidations might occur
+** Type conversions and pointer invalidations might occur
 ** in the following cases:
 **
 ** <ul>
@@ -3683,22 +3759,22 @@
 ** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
 **      sqlite3_column_text() is called.  The content must be converted
 **      to UTF-8.</li>
-** </ul>)^
+** </ul>
 **
 ** ^Conversions between UTF-16be and UTF-16le are always done in place and do
 ** not invalidate a prior pointer, though of course the content of the buffer
-** that the prior pointer points to will have been modified.  Other kinds
+** that the prior pointer references will have been modified.  Other kinds
 ** of conversion are done in place when it is possible, but sometimes they
 ** are not possible and in those cases prior pointers are invalidated.
 **
-** ^(The safest and easiest to remember policy is to invoke these routines
+** The safest and easiest to remember policy is to invoke these routines
 ** in one of the following ways:
 **
 ** <ul>
 **  <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
 **  <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
 **  <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
-** </ul>)^
+** </ul>
 **
 ** In other words, you should call sqlite3_column_text(),
 ** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
@@ -3782,23 +3858,25 @@
 ** KEYWORDS: {application-defined SQL function}
 ** KEYWORDS: {application-defined SQL functions}
 **
-** ^These two functions (collectively known as "function creation routines")
+** ^These functions (collectively known as "function creation routines")
 ** are used to add SQL functions or aggregates or to redefine the behavior
-** of existing SQL functions or aggregates.  The only difference between the
-** two is that the second parameter, the name of the (scalar) function or
-** aggregate, is encoded in UTF-8 for sqlite3_create_function() and UTF-16
-** for sqlite3_create_function16().
+** of existing SQL functions or aggregates.  The only differences between
+** these routines are the text encoding expected for
+** the the second parameter (the name of the function being created)
+** and the presence or absence of a destructor callback for
+** the application data pointer.
 **
 ** ^The first parameter is the [database connection] to which the SQL
 ** function is to be added.  ^If an application uses more than one database
 ** connection then application-defined SQL functions must be added
 ** to each database connection separately.
 **
-** The second parameter is the name of the SQL function to be created or
-** redefined.  ^The length of the name is limited to 255 bytes, exclusive of
-** the zero-terminator.  Note that the name length limit is in bytes, not
-** characters.  ^Any attempt to create a function with a longer name
-** will result in [SQLITE_ERROR] being returned.
+** ^The second parameter is the name of the SQL function to be created or
+** redefined.  ^The length of the name is limited to 255 bytes in a UTF-8
+** representation, exclusive of the zero-terminator.  ^Note that the name
+** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes.  
+** ^Any attempt to create a function with a longer name
+** will result in [SQLITE_MISUSE] being returned.
 **
 ** ^The third parameter (nArg)
 ** is the number of arguments that the SQL function or
@@ -3808,10 +3886,10 @@
 ** parameter is less than -1 or greater than 127 then the behavior is
 ** undefined.
 **
-** The fourth parameter, eTextRep, specifies what
+** ^The fourth parameter, eTextRep, specifies what
 ** [SQLITE_UTF8 | text encoding] this SQL function prefers for
-** its parameters.  Any SQL function implementation should be able to work
-** work with UTF-8, UTF-16le, or UTF-16be.  But some implementations may be
+** its parameters.  Every SQL function implementation must be able to work
+** with UTF-8, UTF-16le, or UTF-16be.  But some implementations may be
 ** more efficient with one encoding than another.  ^An application may
 ** invoke sqlite3_create_function() or sqlite3_create_function16() multiple
 ** times with the same function but with different values of eTextRep.
@@ -3823,13 +3901,21 @@
 ** ^(The fifth parameter is an arbitrary pointer.  The implementation of the
 ** function can gain access to this pointer using [sqlite3_user_data()].)^
 **
-** The seventh, eighth and ninth parameters, xFunc, xStep and xFinal, are
+** ^The seventh, eighth and ninth parameters, xFunc, xStep and xFinal, are
 ** pointers to C-language functions that implement the SQL function or
 ** aggregate. ^A scalar SQL function requires an implementation of the xFunc
-** callback only; NULL pointers should be passed as the xStep and xFinal
+** callback only; NULL pointers must be passed as the xStep and xFinal
 ** parameters. ^An aggregate SQL function requires an implementation of xStep
-** and xFinal and NULL should be passed for xFunc. ^To delete an existing
-** SQL function or aggregate, pass NULL for all three function callbacks.
+** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing
+** SQL function or aggregate, pass NULL poiners for all three function
+** callbacks.
+**
+** ^If the tenth parameter to sqlite3_create_function_v2() is not NULL,
+** then it is invoked when the function is deleted, either by being
+** overloaded or when the database connection closes.
+** ^When the destructure callback of the tenth parameter is invoked, it
+** is passed a single argument which is a copy of the pointer which was
+** the fifth parameter to sqlite3_create_function_v2().
 **
 ** ^It is permitted to register multiple implementations of the same
 ** functions with the same name but with either differing numbers of
@@ -3845,11 +3931,6 @@
 ** between UTF8 and UTF16.
 **
 ** ^Built-in functions may be overloaded by new application-defined functions.
-** ^The first application-defined function with a given name overrides all
-** built-in functions in the same [database connection] with the same name.
-** ^Subsequent application-defined functions of the same name only override 
-** prior application-defined functions that are an exact match for the
-** number of parameters and preferred encoding.
 **
 ** ^An application-defined function is permitted to call other
 ** SQLite interfaces.  However, such calls must not
@@ -3876,6 +3957,17 @@
   void (*xStep)(sqlite3_context*,int,sqlite3_value**),
   void (*xFinal)(sqlite3_context*)
 );
+SQLITE_API int sqlite3_create_function_v2(
+  sqlite3 *db,
+  const char *zFunctionName,
+  int nArg,
+  int eTextRep,
+  void *pApp,
+  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
+  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
+  void (*xFinal)(sqlite3_context*),
+  void(*xDestroy)(void*)
+);
 
 /*
 ** CAPI3REF: Text Encodings
@@ -3970,7 +4062,7 @@
 /*
 ** CAPI3REF: Obtain Aggregate Function Context
 **
-** Implementions of aggregate SQL functions use this
+** Implementations of aggregate SQL functions use this
 ** routine to allocate memory for storing their state.
 **
 ** ^The first time the sqlite3_aggregate_context(C,N) routine is called 
@@ -4222,46 +4314,70 @@
 /*
 ** CAPI3REF: Define New Collating Sequences
 **
-** These functions are used to add new collation sequences to the
-** [database connection] specified as the first argument.
+** ^These functions add, remove, or modify a [collation] associated
+** with the [database connection] specified as the first argument.
 **
-** ^The name of the new collation sequence is specified as a UTF-8 string
+** ^The name of the collation is a UTF-8 string
 ** for sqlite3_create_collation() and sqlite3_create_collation_v2()
-** and a UTF-16 string for sqlite3_create_collation16(). ^In all cases
-** the name is passed as the second function argument.
+** and a UTF-16 string in native byte order for sqlite3_create_collation16().
+** ^Collation names that compare equal according to [sqlite3_strnicmp()] are
+** considered to be the same name.
 **
-** ^The third argument may be one of the constants [SQLITE_UTF8],
-** [SQLITE_UTF16LE], or [SQLITE_UTF16BE], indicating that the user-supplied
-** routine expects to be passed pointers to strings encoded using UTF-8,
-** UTF-16 little-endian, or UTF-16 big-endian, respectively. ^The
-** third argument might also be [SQLITE_UTF16] to indicate that the routine
-** expects pointers to be UTF-16 strings in the native byte order, or the
-** argument can be [SQLITE_UTF16_ALIGNED] if the
-** the routine expects pointers to 16-bit word aligned strings
-** of UTF-16 in the native byte order.
+** ^(The third argument (eTextRep) must be one of the constants:
+** <ul>
+** <li> [SQLITE_UTF8],
+** <li> [SQLITE_UTF16LE],
+** <li> [SQLITE_UTF16BE],
+** <li> [SQLITE_UTF16], or
+** <li> [SQLITE_UTF16_ALIGNED].
+** </ul>)^
+** ^The eTextRep argument determines the encoding of strings passed
+** to the collating function callback, xCallback.
+** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep
+** force strings to be UTF16 with native byte order.
+** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin
+** on an even byte address.
 **
-** A pointer to the user supplied routine must be passed as the fifth
-** argument.  ^If it is NULL, this is the same as deleting the collation
-** sequence (so that SQLite cannot call it anymore).
-** ^Each time the application supplied function is invoked, it is passed
-** as its first parameter a copy of the void* passed as the fourth argument
-** to sqlite3_create_collation() or sqlite3_create_collation16().
+** ^The fourth argument, pArg, is a application data pointer that is passed
+** through as the first argument to the collating function callback.
 **
-** ^The remaining arguments to the application-supplied routine are two strings,
-** each represented by a (length, data) pair and encoded in the encoding
-** that was passed as the third argument when the collation sequence was
-** registered.  The application defined collation routine should
-** return negative, zero or positive if the first string is less than,
-** equal to, or greater than the second string. i.e. (STRING1 - STRING2).
+** ^The fifth argument, xCallback, is a pointer to the collating function.
+** ^Multiple collating functions can be registered using the same name but
+** with different eTextRep parameters and SQLite will use whichever
+** function requires the least amount of data transformation.
+** ^If the xCallback argument is NULL then the collating function is
+** deleted.  ^When all collating functions having the same name are deleted,
+** that collation is no longer usable.
+**
+** ^The collating function callback is invoked with a copy of the pArg 
+** application data pointer and with two strings in the encoding specified
+** by the eTextRep argument.  The collating function must return an
+** integer that is negative, zero, or positive
+** if the first string is less than, equal to, or greater than the second,
+** respectively.  A collating function must alway return the same answer
+** given the same inputs.  If two or more collating functions are registered
+** to the same collation name (using different eTextRep values) then all
+** must give an equivalent answer when invoked with equivalent strings.
+** The collating function must obey the following properties for all
+** strings A, B, and C:
+**
+** <ol>
+** <li> If A==B then B==A.
+** <li> If A==B and B==C then A==C.
+** <li> If A&lt;B THEN B&gt;A.
+** <li> If A&lt;B and B&lt;C then A&lt;C.
+** </ol>
+**
+** If a collating function fails any of the above constraints and that
+** collating function is  registered and used, then the behavior of SQLite
+** is undefined.
 **
 ** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()
-** except that it takes an extra argument which is a destructor for
-** the collation.  ^The destructor is called when the collation is
-** destroyed and is passed a copy of the fourth parameter void* pointer
-** of the sqlite3_create_collation_v2().
-** ^Collations are destroyed when they are overridden by later calls to the
-** collation creation functions or when the [database connection] is closed
-** using [sqlite3_close()].
+** with the addition that the xDestroy callback is invoked on pArg when
+** the collating function is deleted.
+** ^Collating functions are deleted when they are overridden by later
+** calls to the collation creation functions or when the
+** [database connection] is closed using [sqlite3_close()].
 **
 ** See also:  [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
 */
@@ -4269,14 +4385,14 @@
   sqlite3*, 
   const char *zName, 
   int eTextRep, 
-  void*,
+  void *pArg,
   int(*xCompare)(void*,int,const void*,int,const void*)
 );
 SQLITE_API int sqlite3_create_collation_v2(
   sqlite3*, 
   const char *zName, 
   int eTextRep, 
-  void*,
+  void *pArg,
   int(*xCompare)(void*,int,const void*,int,const void*),
   void(*xDestroy)(void*)
 );
@@ -4284,7 +4400,7 @@
   sqlite3*, 
   const void *zName,
   int eTextRep, 
-  void*,
+  void *pArg,
   int(*xCompare)(void*,int,const void*,int,const void*)
 );
 
@@ -4373,16 +4489,19 @@
 /*
 ** CAPI3REF: Suspend Execution For A Short Time
 **
-** ^The sqlite3_sleep() function causes the current thread to suspend execution
+** The sqlite3_sleep() function causes the current thread to suspend execution
 ** for at least a number of milliseconds specified in its parameter.
 **
-** ^If the operating system does not support sleep requests with
+** If the operating system does not support sleep requests with
 ** millisecond time resolution, then the time will be rounded up to
-** the nearest second. ^The number of milliseconds of sleep actually
+** the nearest second. The number of milliseconds of sleep actually
 ** requested from the operating system is returned.
 **
 ** ^SQLite implements this interface by calling the xSleep()
-** method of the default [sqlite3_vfs] object.
+** method of the default [sqlite3_vfs] object.  If the xSleep() method
+** of the default VFS is not implemented correctly, or not implemented at
+** all, then the behavior of sqlite3_sleep() may deviate from the description
+** in the previous paragraphs.
 */
 SQLITE_API int sqlite3_sleep(int);
 
@@ -4604,40 +4723,73 @@
 ** pages to improve performance is an example of non-essential memory.
 ** ^sqlite3_release_memory() returns the number of bytes actually freed,
 ** which might be more or less than the amount requested.
+** ^The sqlite3_release_memory() routine is a no-op returning zero
+** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT].
 */
 SQLITE_API int sqlite3_release_memory(int);
 
 /*
 ** CAPI3REF: Impose A Limit On Heap Size
 **
-** ^The sqlite3_soft_heap_limit() interface places a "soft" limit
-** on the amount of heap memory that may be allocated by SQLite.
-** ^If an internal allocation is requested that would exceed the
-** soft heap limit, [sqlite3_release_memory()] is invoked one or
-** more times to free up some space before the allocation is performed.
+** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the
+** soft limit on the amount of heap memory that may be allocated by SQLite.
+** ^SQLite strives to keep heap memory utilization below the soft heap
+** limit by reducing the number of pages held in the page cache
+** as heap memory usages approaches the limit.
+** ^The soft heap limit is "soft" because even though SQLite strives to stay
+** below the limit, it will exceed the limit rather than generate
+** an [SQLITE_NOMEM] error.  In other words, the soft heap limit 
+** is advisory only.
 **
-** ^The limit is called "soft" because if [sqlite3_release_memory()]
-** cannot free sufficient memory to prevent the limit from being exceeded,
-** the memory is allocated anyway and the current operation proceeds.
+** ^The return value from sqlite3_soft_heap_limit64() is the size of
+** the soft heap limit prior to the call.  ^If the argument N is negative
+** then no change is made to the soft heap limit.  Hence, the current
+** size of the soft heap limit can be determined by invoking
+** sqlite3_soft_heap_limit64() with a negative argument.
 **
-** ^A negative or zero value for N means that there is no soft heap limit and
-** [sqlite3_release_memory()] will only be called when memory is exhausted.
-** ^The default value for the soft heap limit is zero.
+** ^If the argument N is zero then the soft heap limit is disabled.
 **
-** ^(SQLite makes a best effort to honor the soft heap limit.
-** But if the soft heap limit cannot be honored, execution will
-** continue without error or notification.)^  This is why the limit is
-** called a "soft" limit.  It is advisory only.
+** ^(The soft heap limit is not enforced in the current implementation
+** if one or more of following conditions are true:
 **
-** Prior to SQLite version 3.5.0, this routine only constrained the memory
-** allocated by a single thread - the same thread in which this routine
-** runs.  Beginning with SQLite version 3.5.0, the soft heap limit is
-** applied to all threads. The value specified for the soft heap limit
-** is an upper bound on the total memory allocation for all threads. In
-** version 3.5.0 there is no mechanism for limiting the heap usage for
-** individual threads.
+** <ul>
+** <li> The soft heap limit is set to zero.
+** <li> Memory accounting is disabled using a combination of the
+**      [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and
+**      the [SQLITE_DEFAULT_MEMSTATUS] compile-time option.
+** <li> An alternative page cache implementation is specifed using
+**      [sqlite3_config]([SQLITE_CONFIG_PCACHE],...).
+** <li> The page cache allocates from its own memory pool supplied
+**      by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than
+**      from the heap.
+** </ul>)^
+**
+** Beginning with SQLite version 3.7.3, the soft heap limit is enforced
+** regardless of whether or not the [SQLITE_ENABLE_MEMORY_MANAGEMENT]
+** compile-time option is invoked.  With [SQLITE_ENABLE_MEMORY_MANAGEMENT],
+** the soft heap limit is enforced on every memory allocation.  Without
+** [SQLITE_ENABLE_MEMORY_MANAGEMENT], the soft heap limit is only enforced
+** when memory is allocated by the page cache.  Testing suggests that because
+** the page cache is the predominate memory user in SQLite, most
+** applications will achieve adequate soft heap limit enforcement without
+** the use of [SQLITE_ENABLE_MEMORY_MANAGEMENT].
+**
+** The circumstances under which SQLite will enforce the soft heap limit may
+** changes in future releases of SQLite.
 */
-SQLITE_API void sqlite3_soft_heap_limit(int);
+SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N);
+
+/*
+** CAPI3REF: Deprecated Soft Heap Limit Interface
+** DEPRECATED
+**
+** This is a deprecated version of the [sqlite3_soft_heap_limit64()]
+** interface.  This routine is provided for historical compatibility
+** only.  All new applications should use the
+** [sqlite3_soft_heap_limit64()] interface rather than this one.
+*/
+SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N);
+
 
 /*
 ** CAPI3REF: Extract Metadata About A Column Of A Table
@@ -4761,34 +4913,47 @@
 SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
 
 /*
-** CAPI3REF: Automatically Load An Extensions
+** CAPI3REF: Automatically Load Statically Linked Extensions
 **
-** ^This API can be invoked at program startup in order to register
-** one or more statically linked extensions that will be available
-** to all new [database connections].
+** ^This interface causes the xEntryPoint() function to be invoked for
+** each new [database connection] that is created.  The idea here is that
+** xEntryPoint() is the entry point for a statically linked SQLite extension
+** that is to be automatically loaded into all new database connections.
 **
-** ^(This routine stores a pointer to the extension entry point
-** in an array that is obtained from [sqlite3_malloc()].  That memory
-** is deallocated by [sqlite3_reset_auto_extension()].)^
+** ^(Even though the function prototype shows that xEntryPoint() takes
+** no arguments and returns void, SQLite invokes xEntryPoint() with three
+** arguments and expects and integer result as if the signature of the
+** entry point where as follows:
 **
-** ^This function registers an extension entry point that is
-** automatically invoked whenever a new [database connection]
-** is opened using [sqlite3_open()], [sqlite3_open16()],
-** or [sqlite3_open_v2()].
-** ^Duplicate extensions are detected so calling this routine
-** multiple times with the same extension is harmless.
-** ^Automatic extensions apply across all threads.
+** <blockquote><pre>
+** &nbsp;  int xEntryPoint(
+** &nbsp;    sqlite3 *db,
+** &nbsp;    const char **pzErrMsg,
+** &nbsp;    const struct sqlite3_api_routines *pThunk
+** &nbsp;  );
+** </pre></blockquote>)^
+**
+** If the xEntryPoint routine encounters an error, it should make *pzErrMsg
+** point to an appropriate error message (obtained from [sqlite3_mprintf()])
+** and return an appropriate [error code].  ^SQLite ensures that *pzErrMsg
+** is NULL before calling the xEntryPoint().  ^SQLite will invoke
+** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns.  ^If any
+** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()],
+** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail.
+**
+** ^Calling sqlite3_auto_extension(X) with an entry point X that is already
+** on the list of automatic extensions is a harmless no-op. ^No entry point
+** will be called more than once for each database connection that is opened.
+**
+** See also: [sqlite3_reset_auto_extension()].
 */
 SQLITE_API int sqlite3_auto_extension(void (*xEntryPoint)(void));
 
 /*
 ** CAPI3REF: Reset Automatic Extension Loading
 **
-** ^(This function disables all previously registered automatic
-** extensions. It undoes the effect of all prior
-** [sqlite3_auto_extension()] calls.)^
-**
-** ^This function disables automatic extensions in all threads.
+** ^This interface disables all automatic extensions previously
+** registered using [sqlite3_auto_extension()].
 */
 SQLITE_API void sqlite3_reset_auto_extension(void);
 
@@ -4859,7 +5024,8 @@
 ** CAPI3REF: Virtual Table Indexing Information
 ** KEYWORDS: sqlite3_index_info
 **
-** The sqlite3_index_info structure and its substructures is used to
+** The sqlite3_index_info structure and its substructures is used as part
+** of the [virtual table] interface to
 ** pass information into and receive the reply from the [xBestIndex]
 ** method of a [virtual table module].  The fields under **Inputs** are the
 ** inputs to xBestIndex and are read-only.  xBestIndex inserts its
@@ -4867,10 +5033,12 @@
 **
 ** ^(The aConstraint[] array records WHERE clause constraints of the form:
 **
-** <pre>column OP expr</pre>
+** <blockquote>column OP expr</blockquote>
 **
 ** where OP is =, &lt;, &lt;=, &gt;, or &gt;=.)^  ^(The particular operator is
-** stored in aConstraint[].op.)^  ^(The index of the column is stored in
+** stored in aConstraint[].op using one of the
+** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^
+** ^(The index of the column is stored in
 ** aConstraint[].iColumn.)^  ^(aConstraint[].usable is TRUE if the
 ** expr on the right-hand side can be evaluated (and thus the constraint
 ** is usable) and false if it cannot.)^
@@ -4930,6 +5098,15 @@
   int orderByConsumed;       /* True if output is already ordered */
   double estimatedCost;      /* Estimated cost of using this index */
 };
+
+/*
+** CAPI3REF: Virtual Table Constraint Operator Codes
+**
+** These macros defined the allowed values for the
+** [sqlite3_index_info].aConstraint[].op field.  Each value represents
+** an operator that is part of a constraint term in the wHERE clause of
+** a query that uses a [virtual table].
+*/
 #define SQLITE_INDEX_CONSTRAINT_EQ    2
 #define SQLITE_INDEX_CONSTRAINT_GT    4
 #define SQLITE_INDEX_CONSTRAINT_LE    8
@@ -5415,7 +5592,7 @@
 **
 ** ^The xMutexInit method defined by this structure is invoked as
 ** part of system initialization by the sqlite3_initialize() function.
-** ^The xMutexInit routine is calle by SQLite exactly once for each
+** ^The xMutexInit routine is called by SQLite exactly once for each
 ** effective call to [sqlite3_initialize()].
 **
 ** ^The xMutexEnd method defined by this structure is invoked as
@@ -5448,7 +5625,7 @@
 ** it is passed a NULL pointer).
 **
 ** The xMutexInit() method must be threadsafe.  ^It must be harmless to
-** invoke xMutexInit() mutiple times within the same process and without
+** invoke xMutexInit() multiple times within the same process and without
 ** intervening calls to xMutexEnd().  Second and subsequent calls to
 ** xMutexInit() must be no-ops.
 **
@@ -5612,13 +5789,14 @@
 #define SQLITE_TESTCTRL_OPTIMIZATIONS           15
 #define SQLITE_TESTCTRL_ISKEYWORD               16
 #define SQLITE_TESTCTRL_PGHDRSZ                 17
-#define SQLITE_TESTCTRL_LAST                    17
+#define SQLITE_TESTCTRL_SCRATCHMALLOC           18
+#define SQLITE_TESTCTRL_LAST                    18
 
 /*
 ** CAPI3REF: SQLite Runtime Status
 **
 ** ^This interface is used to retrieve runtime status information
-** about the preformance of SQLite, and optionally to reset various
+** about the performance of SQLite, and optionally to reset various
 ** highwater marks.  ^The first argument is an integer code for
 ** the specific parameter to measure.  ^(Recognized integer codes
 ** are of the form [SQLITE_STATUS_MEMORY_USED | SQLITE_STATUS_...].)^
@@ -5631,7 +5809,7 @@
 ** ^(Other parameters record only the highwater mark and not the current
 ** value.  For these latter parameters nothing is written into *pCurrent.)^
 **
-** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a
+** ^The sqlite3_status() routine returns SQLITE_OK on success and a
 ** non-zero [error code] on failure.
 **
 ** This routine is threadsafe but is not atomic.  This routine can be
@@ -5670,6 +5848,9 @@
 ** *pHighwater parameter to [sqlite3_status()] is of interest.  
 ** The value written into the *pCurrent parameter is undefined.</dd>)^
 **
+** ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt>
+** <dd>This parameter records the number of separate memory allocations.</dd>)^
+**
 ** ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt>
 ** <dd>This parameter returns the number of pages used out of the
 ** [pagecache memory allocator] that was configured using 
@@ -5678,7 +5859,7 @@
 **
 ** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
 ** <dd>This parameter returns the number of bytes of page cache
-** allocation which could not be statisfied by the [SQLITE_CONFIG_PAGECACHE]
+** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE]
 ** buffer and where forced to overflow to [sqlite3_malloc()].  The
 ** returned value includes allocations that overflowed because they
 ** where too large (they were larger than the "sz" parameter to
@@ -5701,7 +5882,7 @@
 **
 ** ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
 ** <dd>This parameter returns the number of bytes of scratch memory
-** allocation which could not be statisfied by the [SQLITE_CONFIG_SCRATCH]
+** allocation which could not be satisfied by the [SQLITE_CONFIG_SCRATCH]
 ** buffer and where forced to overflow to [sqlite3_malloc()].  The values
 ** returned include overflows because the requested allocation was too
 ** larger (that is, because the requested allocation was larger than the
@@ -5731,6 +5912,7 @@
 #define SQLITE_STATUS_PARSER_STACK         6
 #define SQLITE_STATUS_PAGECACHE_SIZE       7
 #define SQLITE_STATUS_SCRATCH_SIZE         8
+#define SQLITE_STATUS_MALLOC_COUNT         9
 
 /*
 ** CAPI3REF: Database Connection Status
@@ -5740,7 +5922,7 @@
 ** database connection object to be interrogated.  ^The second argument
 ** is an integer constant, taken from the set of
 ** [SQLITE_DBSTATUS_LOOKASIDE_USED | SQLITE_DBSTATUS_*] macros, that
-** determiness the parameter to interrogate.  The set of 
+** determines the parameter to interrogate.  The set of 
 ** [SQLITE_DBSTATUS_LOOKASIDE_USED | SQLITE_DBSTATUS_*] macros is likely
 ** to grow in future releases of SQLite.
 **
@@ -5749,6 +5931,9 @@
 ** the resetFlg is true, then the highest instantaneous value is
 ** reset back down to the current value.
 **
+** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a
+** non-zero [error code] on failure.
+**
 ** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
 */
 SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
@@ -5770,16 +5955,33 @@
 ** <dd>This parameter returns the number of lookaside memory slots currently
 ** checked out.</dd>)^
 **
-** <dt>SQLITE_DBSTATUS_CACHE_USED</dt>
-** <dd>^This parameter returns the approximate number of of bytes of heap
-** memory used by all pager caches associated with the database connection.
+** ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt>
+** <dd>This parameter returns the approximate number of of bytes of heap
+** memory used by all pager caches associated with the database connection.)^
 ** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0.
-** checked out.</dd>)^
+**
+** ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt>
+** <dd>This parameter returns the approximate number of of bytes of heap
+** memory used to store the schema for all databases associated
+** with the connection - main, temp, and any [ATTACH]-ed databases.)^ 
+** ^The full amount of memory used by the schemas is reported, even if the
+** schema memory is shared with other database connections due to
+** [shared cache mode] being enabled.
+** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0.
+**
+** ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt>
+** <dd>This parameter returns the approximate number of of bytes of heap
+** and lookaside memory used by all prepared statements associated with
+** the database connection.)^
+** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0.
+** </dd>
 ** </dl>
 */
 #define SQLITE_DBSTATUS_LOOKASIDE_USED     0
 #define SQLITE_DBSTATUS_CACHE_USED         1
-#define SQLITE_DBSTATUS_MAX                1   /* Largest defined DBSTATUS */
+#define SQLITE_DBSTATUS_SCHEMA_USED        2
+#define SQLITE_DBSTATUS_STMT_USED          3
+#define SQLITE_DBSTATUS_MAX                3   /* Largest defined DBSTATUS */
 
 
 /*
@@ -5858,32 +6060,42 @@
 **
 ** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE], ...) interface can
 ** register an alternative page cache implementation by passing in an 
-** instance of the sqlite3_pcache_methods structure.)^ The majority of the 
-** heap memory used by SQLite is used by the page cache to cache data read 
-** from, or ready to be written to, the database file. By implementing a 
-** custom page cache using this API, an application can control more 
-** precisely the amount of memory consumed by SQLite, the way in which 
+** instance of the sqlite3_pcache_methods structure.)^
+** In many applications, most of the heap memory allocated by 
+** SQLite is used for the page cache.
+** By implementing a 
+** custom page cache using this API, an application can better control
+** the amount of memory consumed by SQLite, the way in which 
 ** that memory is allocated and released, and the policies used to 
 ** determine exactly which parts of a database file are cached and for 
 ** how long.
 **
+** The alternative page cache mechanism is an
+** extreme measure that is only needed by the most demanding applications.
+** The built-in page cache is recommended for most uses.
+**
 ** ^(The contents of the sqlite3_pcache_methods structure are copied to an
 ** internal buffer by SQLite within the call to [sqlite3_config].  Hence
 ** the application may discard the parameter after the call to
 ** [sqlite3_config()] returns.)^
 **
-** ^The xInit() method is called once for each call to [sqlite3_initialize()]
+** ^(The xInit() method is called once for each effective 
+** call to [sqlite3_initialize()])^
 ** (usually only once during the lifetime of the process). ^(The xInit()
 ** method is passed a copy of the sqlite3_pcache_methods.pArg value.)^
-** ^The xInit() method can set up up global structures and/or any mutexes
+** The intent of the xInit() method is to set up global data structures 
 ** required by the custom page cache implementation. 
+** ^(If the xInit() method is NULL, then the 
+** built-in default page cache is used instead of the application defined
+** page cache.)^
 **
-** ^The xShutdown() method is called from within [sqlite3_shutdown()], 
-** if the application invokes this API. It can be used to clean up 
+** ^The xShutdown() method is called by [sqlite3_shutdown()].
+** It can be used to clean up 
 ** any outstanding resources before process shutdown, if required.
+** ^The xShutdown() method may be NULL.
 **
-** ^SQLite holds a [SQLITE_MUTEX_RECURSIVE] mutex when it invokes
-** the xInit method, so the xInit method need not be threadsafe.  ^The
+** ^SQLite automatically serializes calls to the xInit method,
+** so the xInit method need not be threadsafe.  ^The
 ** xShutdown method is only called from [sqlite3_shutdown()] so it does
 ** not need to be threadsafe either.  All other methods must be threadsafe
 ** in multithreaded applications.
@@ -5891,47 +6103,50 @@
 ** ^SQLite will never invoke xInit() more than once without an intervening
 ** call to xShutdown().
 **
-** ^The xCreate() method is used to construct a new cache instance.  SQLite
-** will typically create one cache instance for each open database file,
+** ^SQLite invokes the xCreate() method to construct a new cache instance.
+** SQLite will typically create one cache instance for each open database file,
 ** though this is not guaranteed. ^The
 ** first parameter, szPage, is the size in bytes of the pages that must
 ** be allocated by the cache.  ^szPage will not be a power of two.  ^szPage
 ** will the page size of the database file that is to be cached plus an
-** increment (here called "R") of about 100 or 200.  ^SQLite will use the
+** increment (here called "R") of about 100 or 200.  SQLite will use the
 ** extra R bytes on each page to store metadata about the underlying
 ** database page on disk.  The value of R depends
 ** on the SQLite version, the target platform, and how SQLite was compiled.
 ** ^R is constant for a particular build of SQLite.  ^The second argument to
 ** xCreate(), bPurgeable, is true if the cache being created will
 ** be used to cache database pages of a file stored on disk, or
-** false if it is used for an in-memory database. ^The cache implementation
+** false if it is used for an in-memory database. The cache implementation
 ** does not have to do anything special based with the value of bPurgeable;
 ** it is purely advisory.  ^On a cache where bPurgeable is false, SQLite will
 ** never invoke xUnpin() except to deliberately delete a page.
-** ^In other words, a cache created with bPurgeable set to false will
+** ^In other words, calls to xUnpin() on a cache with bPurgeable set to
+** false will always have the "discard" flag set to true.  
+** ^Hence, a cache created with bPurgeable false will
 ** never contain any unpinned pages.
 **
 ** ^(The xCachesize() method may be called at any time by SQLite to set the
 ** suggested maximum cache-size (number of pages stored by) the cache
 ** instance passed as the first argument. This is the value configured using
-** the SQLite "[PRAGMA cache_size]" command.)^  ^As with the bPurgeable
+** the SQLite "[PRAGMA cache_size]" command.)^  As with the bPurgeable
 ** parameter, the implementation is not required to do anything with this
 ** value; it is advisory only.
 **
-** ^The xPagecount() method should return the number of pages currently
-** stored in the cache.
+** The xPagecount() method must return the number of pages currently
+** stored in the cache, both pinned and unpinned.
 ** 
-** ^The xFetch() method is used to fetch a page and return a pointer to it. 
-** ^A 'page', in this context, is a buffer of szPage bytes aligned at an
-** 8-byte boundary. ^The page to be fetched is determined by the key. ^The
-** mimimum key value is 1. After it has been retrieved using xFetch, the page 
+** The xFetch() method locates a page in the cache and returns a pointer to 
+** the page, or a NULL pointer.
+** A "page", in this context, means a buffer of szPage bytes aligned at an
+** 8-byte boundary. The page to be fetched is determined by the key. ^The
+** mimimum key value is 1.  After it has been retrieved using xFetch, the page 
 ** is considered to be "pinned".
 **
-** ^If the requested page is already in the page cache, then the page cache
+** If the requested page is already in the page cache, then the page cache
 ** implementation must return a pointer to the page buffer with its content
-** intact.  ^(If the requested page is not already in the cache, then the
-** behavior of the cache implementation is determined by the value of the
-** createFlag parameter passed to xFetch, according to the following table:
+** intact.  If the requested page is not already in the cache, then the
+** behavior of the cache implementation should use the value of the createFlag
+** parameter to help it determined what action to take:
 **
 ** <table border=1 width=85% align=center>
 ** <tr><th> createFlag <th> Behaviour when page is not already in cache
@@ -5940,36 +6155,35 @@
 **                 Otherwise return NULL.
 ** <tr><td> 2 <td> Make every effort to allocate a new page.  Only return
 **                 NULL if allocating a new page is effectively impossible.
-** </table>)^
+** </table>
 **
-** SQLite will normally invoke xFetch() with a createFlag of 0 or 1.  If
-** a call to xFetch() with createFlag==1 returns NULL, then SQLite will
+** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1.  SQLite
+** will only use a createFlag of 2 after a prior call with a createFlag of 1
+** failed.)^  In between the to xFetch() calls, SQLite may
 ** attempt to unpin one or more cache pages by spilling the content of
-** pinned pages to disk and synching the operating system disk cache. After
-** attempting to unpin pages, the xFetch() method will be invoked again with
-** a createFlag of 2.
+** pinned pages to disk and synching the operating system disk cache.
 **
 ** ^xUnpin() is called by SQLite with a pointer to a currently pinned page
-** as its second argument. ^(If the third parameter, discard, is non-zero,
-** then the page should be evicted from the cache. In this case SQLite 
-** assumes that the next time the page is retrieved from the cache using
-** the xFetch() method, it will be zeroed.)^ ^If the discard parameter is
-** zero, then the page is considered to be unpinned. ^The cache implementation
+** as its second argument.  If the third parameter, discard, is non-zero,
+** then the page must be evicted from the cache.
+** ^If the discard parameter is
+** zero, then the page may be discarded or retained at the discretion of
+** page cache implementation. ^The page cache implementation
 ** may choose to evict unpinned pages at any time.
 **
-** ^(The cache is not required to perform any reference counting. A single 
+** The cache must not perform any reference counting. A single 
 ** call to xUnpin() unpins the page regardless of the number of prior calls 
-** to xFetch().)^
+** to xFetch().
 **
-** ^The xRekey() method is used to change the key value associated with the
-** page passed as the second argument from oldKey to newKey. ^If the cache
-** previously contains an entry associated with newKey, it should be
+** The xRekey() method is used to change the key value associated with the
+** page passed as the second argument. If the cache
+** previously contains an entry associated with newKey, it must be
 ** discarded. ^Any prior cache entry associated with newKey is guaranteed not
 ** to be pinned.
 **
-** ^When SQLite calls the xTruncate() method, the cache must discard all
+** When SQLite calls the xTruncate() method, the cache must discard all
 ** existing cache entries with page numbers (keys) greater than or equal
-** to the value of the iLimit parameter passed to xTruncate(). ^If any
+** to the value of the iLimit parameter passed to xTruncate(). If any
 ** of these pages are pinned, they are implicitly unpinned, meaning that
 ** they can be safely discarded.
 **
@@ -6145,7 +6359,7 @@
 **
 ** ^Each call to sqlite3_backup_step() sets two values inside
 ** the [sqlite3_backup] object: the number of pages still to be backed
-** up and the total number of pages in the source databae file.
+** up and the total number of pages in the source database file.
 ** The sqlite3_backup_remaining() and sqlite3_backup_pagecount() interfaces
 ** retrieve these two values, respectively.
 **
@@ -6241,7 +6455,7 @@
 ** blocked connection already has a registered unlock-notify callback,
 ** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is
 ** called with a NULL pointer as its second argument, then any existing
-** unlock-notify callback is cancelled. ^The blocked connections 
+** unlock-notify callback is canceled. ^The blocked connections 
 ** unlock-notify callback may also be canceled by closing the blocked
 ** connection using [sqlite3_close()].
 **
@@ -6323,7 +6537,7 @@
 **
 ** ^The [sqlite3_strnicmp()] API allows applications and extensions to
 ** compare the contents of two buffers containing UTF-8 strings in a
-** case-indendent fashion, using the same definition of case independence 
+** case-independent fashion, using the same definition of case independence 
 ** that SQLite uses internally when comparing identifiers.
 */
 SQLITE_API int sqlite3_strnicmp(const char *, const char *, int);
@@ -6447,6 +6661,62 @@
 #endif
 #endif
 
+/*
+** 2010 August 30
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+*/
+
+#ifndef _SQLITE3RTREE_H_
+#define _SQLITE3RTREE_H_
+
+
+#if 0
+extern "C" {
+#endif
+
+typedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry;
+
+/*
+** Register a geometry callback named zGeom that can be used as part of an
+** R-Tree geometry query as follows:
+**
+**   SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zGeom(... params ...)
+*/
+SQLITE_API int sqlite3_rtree_geometry_callback(
+  sqlite3 *db,
+  const char *zGeom,
+  int (*xGeom)(sqlite3_rtree_geometry *, int nCoord, double *aCoord, int *pRes),
+  void *pContext
+);
+
+
+/*
+** A pointer to a structure of the following type is passed as the first
+** argument to callbacks registered using rtree_geometry_callback().
+*/
+struct sqlite3_rtree_geometry {
+  void *pContext;                 /* Copy of pContext passed to s_r_g_c() */
+  int nParam;                     /* Size of array aParam[] */
+  double *aParam;                 /* Parameters passed to SQL geom function */
+  void *pUser;                    /* Callback implementation user data */
+  void (*xDelUser)(void *);       /* Called by SQLite to clean up pUser */
+};
+
+
+#if 0
+}  /* end of the 'extern "C"' block */
+#endif
+
+#endif  /* ifndef _SQLITE3RTREE_H_ */
+
 
 /************** End of sqlite3.h *********************************************/
 /************** Continuing where we left off in sqliteInt.h ******************/
@@ -7017,6 +7287,7 @@
 typedef struct ExprList ExprList;
 typedef struct ExprSpan ExprSpan;
 typedef struct FKey FKey;
+typedef struct FuncDestructor FuncDestructor;
 typedef struct FuncDef FuncDef;
 typedef struct FuncDefHash FuncDefHash;
 typedef struct IdList IdList;
@@ -7123,12 +7394,11 @@
 ** NOTE:  These values must match the corresponding PAGER_ values in
 ** pager.h.
 */
-#define BTREE_OMIT_JOURNAL  1  /* Do not use journal.  No argument */
+#define BTREE_OMIT_JOURNAL  1  /* Do not create or use a rollback journal */
 #define BTREE_NO_READLOCK   2  /* Omit readlocks on readonly files */
-#define BTREE_MEMORY        4  /* In-memory DB.  No argument */
-#define BTREE_READONLY      8  /* Open the database in read-only mode */
-#define BTREE_READWRITE    16  /* Open for both reading and writing */
-#define BTREE_CREATE       32  /* Create the database if it does not exist */
+#define BTREE_MEMORY        4  /* This is an in-memory DB */
+#define BTREE_SINGLE        8  /* The file contains at most 1 b-tree */
+#define BTREE_UNORDERED    16  /* Use of a hash implementation is OK */
 
 SQLITE_PRIVATE int sqlite3BtreeClose(Btree*);
 SQLITE_PRIVATE int sqlite3BtreeSetCacheSize(Btree*,int);
@@ -7164,11 +7434,17 @@
 SQLITE_PRIVATE int sqlite3BtreeIncrVacuum(Btree *);
 
 /* The flags parameter to sqlite3BtreeCreateTable can be the bitwise OR
-** of the following flags:
+** of the flags shown below.
+**
+** Every SQLite table must have either BTREE_INTKEY or BTREE_BLOBKEY set.
+** With BTREE_INTKEY, the table key is a 64-bit integer and arbitrary data
+** is stored in the leaves.  (BTREE_INTKEY is used for SQL tables.)  With
+** BTREE_BLOBKEY, the key is an arbitrary BLOB and no content is stored
+** anywhere - the key is the content.  (BTREE_BLOBKEY is used for SQL
+** indices.)
 */
 #define BTREE_INTKEY     1    /* Table has only 64-bit signed integer keys */
-#define BTREE_ZERODATA   2    /* Table has keys only - no data */
-#define BTREE_LEAFDATA   4    /* Data stored in leaves only.  Implies INTKEY */
+#define BTREE_BLOBKEY    2    /* Table has keys only - no data */
 
 SQLITE_PRIVATE int sqlite3BtreeDropTable(Btree*, int, int*);
 SQLITE_PRIVATE int sqlite3BtreeClearTable(Btree*, int, int*);
@@ -7257,6 +7533,10 @@
 SQLITE_PRIVATE void sqlite3BtreeCursorList(Btree*);
 #endif
 
+#ifndef SQLITE_OMIT_WAL
+SQLITE_PRIVATE   int sqlite3BtreeCheckpoint(Btree*);
+#endif
+
 /*
 ** If we are not using shared cache, then there is no need to
 ** use mutexes to access the BtShared structures.  So make the
@@ -7386,8 +7666,8 @@
   int nOp;                      /* Elements in aOp[] */
   int nMem;                     /* Number of memory cells required */
   int nCsr;                     /* Number of cursors required */
-  int nRef;                     /* Number of pointers to this structure */
   void *token;                  /* id that may be used to recursive triggers */
+  SubProgram *pNext;            /* Next sub-program already visited */
 };
 
 /*
@@ -7675,6 +7955,7 @@
 SQLITE_PRIVATE int sqlite3VdbeMakeLabel(Vdbe*);
 SQLITE_PRIVATE void sqlite3VdbeRunOnlyOnce(Vdbe*);
 SQLITE_PRIVATE void sqlite3VdbeDelete(Vdbe*);
+SQLITE_PRIVATE void sqlite3VdbeDeleteObject(sqlite3*,Vdbe*);
 SQLITE_PRIVATE void sqlite3VdbeMakeReady(Vdbe*,int,int,int,int,int,int);
 SQLITE_PRIVATE int sqlite3VdbeFinalize(Vdbe*);
 SQLITE_PRIVATE void sqlite3VdbeResolveLabel(Vdbe*, int);
@@ -7692,7 +7973,6 @@
 SQLITE_PRIVATE void sqlite3VdbeSetSql(Vdbe*, const char *z, int n, int);
 SQLITE_PRIVATE void sqlite3VdbeSwap(Vdbe*,Vdbe*);
 SQLITE_PRIVATE VdbeOp *sqlite3VdbeTakeOpArray(Vdbe*, int*, int*);
-SQLITE_PRIVATE void sqlite3VdbeProgramDelete(sqlite3 *, SubProgram *, int);
 SQLITE_PRIVATE sqlite3_value *sqlite3VdbeGetValue(Vdbe*, int, u8);
 SQLITE_PRIVATE void sqlite3VdbeSetVarmask(Vdbe*, int);
 #ifndef SQLITE_OMIT_TRACE
@@ -7703,6 +7983,10 @@
 SQLITE_PRIVATE void sqlite3VdbeDeleteUnpackedRecord(UnpackedRecord*);
 SQLITE_PRIVATE int sqlite3VdbeRecordCompare(int,const void*,UnpackedRecord*);
 
+#ifndef SQLITE_OMIT_TRIGGER
+SQLITE_PRIVATE void sqlite3VdbeLinkSubProgram(Vdbe *, SubProgram *);
+#endif
+
 
 #ifndef NDEBUG
 SQLITE_PRIVATE   void sqlite3VdbeComment(Vdbe*, const char*, ...);
@@ -7781,6 +8065,7 @@
 */
 #define PAGER_OMIT_JOURNAL  0x0001    /* Do not use a rollback journal */
 #define PAGER_NO_READLOCK   0x0002    /* Omit readlocks on readonly files */
+#define PAGER_MEMORY        0x0004    /* In-memory database */
 
 /*
 ** Valid values for the second argument to sqlite3PagerLockingMode().
@@ -7821,7 +8106,7 @@
 
 /* Functions used to configure a Pager object. */
 SQLITE_PRIVATE void sqlite3PagerSetBusyhandler(Pager*, int(*)(void *), void *);
-SQLITE_PRIVATE int sqlite3PagerSetPagesize(Pager*, u16*, int);
+SQLITE_PRIVATE int sqlite3PagerSetPagesize(Pager*, u32*, int);
 SQLITE_PRIVATE int sqlite3PagerMaxPageCount(Pager*, int);
 SQLITE_PRIVATE void sqlite3PagerSetCachesize(Pager*, int);
 SQLITE_PRIVATE void sqlite3PagerSetSafetyLevel(Pager*,int,int);
@@ -7848,9 +8133,10 @@
 SQLITE_PRIVATE void *sqlite3PagerGetExtra(DbPage *); 
 
 /* Functions used to manage pager transactions and savepoints. */
-SQLITE_PRIVATE int sqlite3PagerPagecount(Pager*, int*);
+SQLITE_PRIVATE void sqlite3PagerPagecount(Pager*, int*);
 SQLITE_PRIVATE int sqlite3PagerBegin(Pager*, int exFlag, int);
 SQLITE_PRIVATE int sqlite3PagerCommitPhaseOne(Pager*,const char *zMaster, int);
+SQLITE_PRIVATE int sqlite3PagerExclusiveLock(Pager*);
 SQLITE_PRIVATE int sqlite3PagerSync(Pager *pPager);
 SQLITE_PRIVATE int sqlite3PagerCommitPhaseTwo(Pager*);
 SQLITE_PRIVATE int sqlite3PagerRollback(Pager*);
@@ -8314,11 +8600,10 @@
 #define SQLITE_FCNTL_DB_UNCHANGED 0xca093fa0
 SQLITE_PRIVATE int sqlite3OsSectorSize(sqlite3_file *id);
 SQLITE_PRIVATE int sqlite3OsDeviceCharacteristics(sqlite3_file *id);
-SQLITE_PRIVATE int sqlite3OsShmOpen(sqlite3_file *id);
+SQLITE_PRIVATE int sqlite3OsShmMap(sqlite3_file *,int,int,int,void volatile **);
 SQLITE_PRIVATE int sqlite3OsShmLock(sqlite3_file *id, int, int, int);
 SQLITE_PRIVATE void sqlite3OsShmBarrier(sqlite3_file *id);
-SQLITE_PRIVATE int sqlite3OsShmClose(sqlite3_file *id, int);
-SQLITE_PRIVATE int sqlite3OsShmMap(sqlite3_file *,int,int,int,void volatile **);
+SQLITE_PRIVATE int sqlite3OsShmUnmap(sqlite3_file *id, int);
 
 /* 
 ** Functions for accessing sqlite3_vfs methods 
@@ -8415,8 +8700,8 @@
 #define sqlite3_mutex_enter(X)
 #define sqlite3_mutex_try(X)      SQLITE_OK
 #define sqlite3_mutex_leave(X)
-#define sqlite3_mutex_held(X)     1
-#define sqlite3_mutex_notheld(X)  1
+#define sqlite3_mutex_held(X)     ((void)(X),1)
+#define sqlite3_mutex_notheld(X)  ((void)(X),1)
 #define sqlite3MutexAlloc(X)      ((sqlite3_mutex*)8)
 #define sqlite3MutexInit()        SQLITE_OK
 #define sqlite3MutexEnd()
@@ -8443,14 +8728,6 @@
 
 /*
 ** An instance of the following structure stores a database schema.
-**
-** If there are no virtual tables configured in this schema, the
-** Schema.db variable is set to NULL. After the first virtual table
-** has been added, it is set to point to the database connection 
-** used to create the connection. Once a virtual table has been
-** added to the Schema structure and the Schema.db variable populated, 
-** only that database connection may use the Schema to prepare 
-** statements.
 */
 struct Schema {
   int schema_cookie;   /* Database schema version number for this file */
@@ -8463,9 +8740,6 @@
   u8 enc;              /* Text encoding used by this database */
   u16 flags;           /* Flags associated with this schema */
   int cache_size;      /* Number of pages to use in the cache */
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-  sqlite3 *db;         /* "Owner" connection. See comment above */
-#endif
 };
 
 /*
@@ -8579,7 +8853,6 @@
   u8 temp_store;                /* 1: file 2: memory 0: default */
   u8 mallocFailed;              /* True if we have seen a malloc failure */
   u8 dfltLockMode;              /* Default locking-mode for attached dbs */
-  u8 dfltJournalMode;           /* Default journal mode for attached dbs */
   signed char nextAutovac;      /* Autovac setting after VACUUM if >=0 */
   u8 suppressErr;               /* Do not issue error messages if true */
   int nextPagesize;             /* Pagesize after VACUUM if >0 */
@@ -8654,6 +8927,7 @@
   int nStatement;               /* Number of nested statement-transactions  */
   u8 isTransactionSavepoint;    /* True if the outermost savepoint is a TS */
   i64 nDeferredCons;            /* Net deferred constraints this transaction. */
+  int *pnBytesFreed;            /* If not NULL, increment this in DbFree() */
 
 #ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
   /* The following variables are all protected by the STATIC_MASTER 
@@ -8749,6 +9023,27 @@
   void (*xFinalize)(sqlite3_context*);                /* Aggregate finalizer */
   char *zName;         /* SQL name of the function. */
   FuncDef *pHash;      /* Next with a different name but the same hash */
+  FuncDestructor *pDestructor;   /* Reference counted destructor function */
+};
+
+/*
+** This structure encapsulates a user-function destructor callback (as
+** configured using create_function_v2()) and a reference counter. When
+** create_function_v2() is called to create a function with a destructor,
+** a single object of this type is allocated. FuncDestructor.nRef is set to 
+** the number of FuncDef objects created (either 1 or 3, depending on whether
+** or not the specified encoding is SQLITE_ANY). The FuncDef.pDestructor
+** member of each of the new FuncDef objects is set to point to the allocated
+** FuncDestructor.
+**
+** Thereafter, when one of the FuncDef objects is deleted, the reference
+** count on this object is decremented. When it reaches 0, the destructor
+** is invoked and the FuncDestructor structure freed.
+*/
+struct FuncDestructor {
+  int nRef;
+  void (*xDestroy)(void *);
+  void *pUserData;
 };
 
 /*
@@ -9011,13 +9306,13 @@
 ** of a SELECT statement.
 */
 struct Table {
-  sqlite3 *dbMem;      /* DB connection used for lookaside allocations. */
   char *zName;         /* Name of the table or view */
   int iPKey;           /* If not negative, use aCol[iPKey] as the primary key */
   int nCol;            /* Number of columns in this table */
   Column *aCol;        /* Information about each column */
   Index *pIndex;       /* List of SQL indexes on this table. */
   int tnum;            /* Root BTree node for this table (see note above) */
+  unsigned nRowEst;    /* Estimated rows in table - from sqlite_stat1 table */
   Select *pSelect;     /* NULL for tables.  Points to definition if a view. */
   u16 nRef;            /* Number of pointers to this Table */
   u8 tabFlags;         /* Mask of TF_* values */
@@ -9148,9 +9443,9 @@
 */
 struct KeyInfo {
   sqlite3 *db;        /* The database connection */
-  u8 enc;             /* Text encoding - one of the TEXT_Utf* values */
+  u8 enc;             /* Text encoding - one of the SQLITE_UTF* values */
   u16 nField;         /* Number of entries in aColl[] */
-  u8 *aSortOrder;     /* If defined an aSortOrder[i] is true, sort DESC */
+  u8 *aSortOrder;     /* Sort order for each column.  May be NULL */
   CollSeq *aColl[1];  /* Collating sequence for each term of the key */
 };
 
@@ -10120,7 +10415,7 @@
   int  nAlloc;         /* Amount of space allocated in zText */
   int  mxAlloc;        /* Maximum allowed string length */
   u8   mallocFailed;   /* Becomes true if any memory allocation fails */
-  u8   useMalloc;      /* True if zText is enlargeable using realloc */
+  u8   useMalloc;      /* 0: none,  1: sqlite3DbMalloc,  2: sqlite3_malloc */
   u8   tooBig;         /* Becomes true if string size exceeds limits */
 };
 
@@ -10296,7 +10591,7 @@
 SQLITE_PRIVATE void sqlite3PageFree(void*);
 SQLITE_PRIVATE void sqlite3MemSetDefault(void);
 SQLITE_PRIVATE void sqlite3BenignMallocHooks(void (*)(void), void (*)(void));
-SQLITE_PRIVATE int sqlite3MemoryAlarm(void (*)(void*, sqlite3_int64, int), void*, sqlite3_int64);
+SQLITE_PRIVATE int sqlite3HeapNearlyFull(void);
 
 /*
 ** On systems with ample stack space and that support alloca(), make
@@ -10418,7 +10713,7 @@
 #endif
 
 SQLITE_PRIVATE void sqlite3DropTable(Parse*, SrcList*, int, int);
-SQLITE_PRIVATE void sqlite3DeleteTable(Table*);
+SQLITE_PRIVATE void sqlite3DeleteTable(sqlite3*, Table*);
 #ifndef SQLITE_OMIT_AUTOINCREMENT
 SQLITE_PRIVATE   void sqlite3AutoincrementBegin(Parse *pParse);
 SQLITE_PRIVATE   void sqlite3AutoincrementEnd(Parse *pParse);
@@ -10467,7 +10762,6 @@
 SQLITE_PRIVATE void sqlite3ExprCacheRemove(Parse*, int, int);
 SQLITE_PRIVATE void sqlite3ExprCacheClear(Parse*);
 SQLITE_PRIVATE void sqlite3ExprCacheAffinityChange(Parse*, int, int);
-SQLITE_PRIVATE void sqlite3ExprHardCopy(Parse*,int,int);
 SQLITE_PRIVATE int sqlite3ExprCode(Parse*, Expr*, int);
 SQLITE_PRIVATE int sqlite3ExprCodeTemp(Parse*, Expr*, int*);
 SQLITE_PRIVATE int sqlite3ExprCodeTarget(Parse*, Expr*, int);
@@ -10587,8 +10881,6 @@
 #endif
 SQLITE_PRIVATE void sqlite3Attach(Parse*, Expr*, Expr*, Expr*);
 SQLITE_PRIVATE void sqlite3Detach(Parse*, Expr*);
-SQLITE_PRIVATE int sqlite3BtreeFactory(sqlite3 *db, const char *zFilename,
-                       int omitJournal, int nCache, int flags, Btree **ppBtree);
 SQLITE_PRIVATE int sqlite3FixInit(DbFixer*, Parse*, int, const char*, const Token*);
 SQLITE_PRIVATE int sqlite3FixSrcList(DbFixer*, SrcList*);
 SQLITE_PRIVATE int sqlite3FixSelect(DbFixer*, Select*);
@@ -10652,7 +10944,8 @@
 SQLITE_PRIVATE CollSeq *sqlite3FindCollSeq(sqlite3*,u8 enc, const char*,int);
 SQLITE_PRIVATE CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char*zName);
 SQLITE_PRIVATE CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr);
-SQLITE_PRIVATE Expr *sqlite3ExprSetColl(Parse *pParse, Expr *, Token *);
+SQLITE_PRIVATE Expr *sqlite3ExprSetColl(Expr*, CollSeq*);
+SQLITE_PRIVATE Expr *sqlite3ExprSetCollByToken(Parse *pParse, Expr*, Token*);
 SQLITE_PRIVATE int sqlite3CheckCollSeq(Parse *, CollSeq *);
 SQLITE_PRIVATE int sqlite3CheckObjectName(Parse *, const char *);
 SQLITE_PRIVATE void sqlite3VdbeSetChanges(sqlite3 *, int);
@@ -10673,6 +10966,7 @@
 SQLITE_PRIVATE const unsigned char sqlite3OpcodeProperty[];
 SQLITE_PRIVATE const unsigned char sqlite3UpperToLower[];
 SQLITE_PRIVATE const unsigned char sqlite3CtypeMap[];
+SQLITE_PRIVATE const Token sqlite3IntTokens[];
 SQLITE_PRIVATE SQLITE_WSD struct Sqlite3Config sqlite3Config;
 SQLITE_PRIVATE SQLITE_WSD FuncDefHash sqlite3GlobalFunctions;
 #ifndef SQLITE_OMIT_WSD
@@ -10701,7 +10995,7 @@
 SQLITE_PRIVATE int sqlite3FindDb(sqlite3*, Token*);
 SQLITE_PRIVATE int sqlite3FindDbName(sqlite3 *, const char *);
 SQLITE_PRIVATE int sqlite3AnalysisLoad(sqlite3*,int iDB);
-SQLITE_PRIVATE void sqlite3DeleteIndexSamples(Index*);
+SQLITE_PRIVATE void sqlite3DeleteIndexSamples(sqlite3*,Index*);
 SQLITE_PRIVATE void sqlite3DefaultRowEst(Index*);
 SQLITE_PRIVATE void sqlite3RegisterLikeFunctions(sqlite3*, int);
 SQLITE_PRIVATE int sqlite3IsLikeFunction(sqlite3*,Expr*,int*,char*);
@@ -10712,7 +11006,9 @@
 SQLITE_PRIVATE KeyInfo *sqlite3IndexKeyinfo(Parse *, Index *);
 SQLITE_PRIVATE int sqlite3CreateFunc(sqlite3 *, const char *, int, int, void *, 
   void (*)(sqlite3_context*,int,sqlite3_value **),
-  void (*)(sqlite3_context*,int,sqlite3_value **), void (*)(sqlite3_context*));
+  void (*)(sqlite3_context*,int,sqlite3_value **), void (*)(sqlite3_context*),
+  FuncDestructor *pDestructor
+);
 SQLITE_PRIVATE int sqlite3ApiExit(sqlite3 *db, int);
 SQLITE_PRIVATE int sqlite3OpenTempDatabase(Parse *);
 
@@ -10763,7 +11059,7 @@
 #  define sqlite3VtabUnlock(X)
 #  define sqlite3VtabUnlockList(X)
 #else
-SQLITE_PRIVATE    void sqlite3VtabClear(Table*);
+SQLITE_PRIVATE    void sqlite3VtabClear(sqlite3 *db, Table*);
 SQLITE_PRIVATE    int sqlite3VtabSync(sqlite3 *db, char **);
 SQLITE_PRIVATE    int sqlite3VtabRollback(sqlite3 *db);
 SQLITE_PRIVATE    int sqlite3VtabCommit(sqlite3 *db);
@@ -10816,9 +11112,9 @@
   #define sqlite3FkRequired(a,b,c,d) 0
 #endif
 #ifndef SQLITE_OMIT_FOREIGN_KEY
-SQLITE_PRIVATE   void sqlite3FkDelete(Table*);
+SQLITE_PRIVATE   void sqlite3FkDelete(sqlite3 *, Table*);
 #else
-  #define sqlite3FkDelete(a)
+  #define sqlite3FkDelete(a,b)
 #endif
 
 
@@ -10911,17 +11207,18 @@
 ** sqlite3MemdebugHasType() returns true if any of the bits in its second
 ** argument match the type set by the previous sqlite3MemdebugSetType().
 ** sqlite3MemdebugHasType() is intended for use inside assert() statements.
-** For example:
 **
-**     assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
+** sqlite3MemdebugNoType() returns true if none of the bits in its second
+** argument match the type set by the previous sqlite3MemdebugSetType().
 **
 ** Perhaps the most important point is the difference between MEMTYPE_HEAP
-** and MEMTYPE_DB.  If an allocation is MEMTYPE_DB, that means it might have
-** been allocated by lookaside, except the allocation was too large or
-** lookaside was already full.  It is important to verify that allocations
-** that might have been satisfied by lookaside are not passed back to 
-** non-lookaside free() routines.  Asserts such as the example above are
-** placed on the non-lookaside free() routines to verify this constraint. 
+** and MEMTYPE_LOOKASIDE.  If an allocation is MEMTYPE_LOOKASIDE, that means
+** it might have been allocated by lookaside, except the allocation was
+** too large or lookaside was already full.  It is important to verify
+** that allocations that might have been satisfied by lookaside are not
+** passed back to non-lookaside free() routines.  Asserts such as the
+** example above are placed on the non-lookaside free() routines to verify
+** this constraint. 
 **
 ** All of this is no-op for a production build.  It only comes into
 ** play when the SQLITE_MEMDEBUG compile-time option is used.
@@ -10929,14 +11226,17 @@
 #ifdef SQLITE_MEMDEBUG
 SQLITE_PRIVATE   void sqlite3MemdebugSetType(void*,u8);
 SQLITE_PRIVATE   int sqlite3MemdebugHasType(void*,u8);
+SQLITE_PRIVATE   int sqlite3MemdebugNoType(void*,u8);
 #else
 # define sqlite3MemdebugSetType(X,Y)  /* no-op */
 # define sqlite3MemdebugHasType(X,Y)  1
+# define sqlite3MemdebugNoType(X,Y)   1
 #endif
-#define MEMTYPE_HEAP     0x01    /* General heap allocations */
-#define MEMTYPE_DB       0x02    /* Associated with a database connection */
-#define MEMTYPE_SCRATCH  0x04    /* Scratch allocations */
-#define MEMTYPE_PCACHE   0x08    /* Page cache allocations */
+#define MEMTYPE_HEAP       0x01  /* General heap allocations */
+#define MEMTYPE_LOOKASIDE  0x02  /* Might have been lookaside memory */
+#define MEMTYPE_SCRATCH    0x04  /* Scratch allocations */
+#define MEMTYPE_PCACHE     0x08  /* Page cache allocations */
+#define MEMTYPE_DB         0x10  /* Uses sqlite3DbMalloc, not sqlite_malloc */
 
 #endif /* _SQLITEINT_H_ */
 
@@ -11120,6 +11420,15 @@
 SQLITE_PRIVATE SQLITE_WSD FuncDefHash sqlite3GlobalFunctions;
 
 /*
+** Constant tokens for values 0 and 1.
+*/
+SQLITE_PRIVATE const Token sqlite3IntTokens[] = {
+   { "0", 1 },
+   { "1", 1 }
+};
+
+
+/*
 ** The value of the "pending" byte must be 0x40000000 (1 byte past the
 ** 1-gibabyte boundary) in a compatible database.  SQLite never uses
 ** the database page that contains the pending byte.  It never attempts
@@ -11558,14 +11867,454 @@
 ** This module implements the sqlite3_status() interface and related
 ** functionality.
 */
+/************** Include vdbeInt.h in the middle of status.c ******************/
+/************** Begin file vdbeInt.h *****************************************/
+/*
+** 2003 September 6
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This is the header file for information that is private to the
+** VDBE.  This information used to all be at the top of the single
+** source code file "vdbe.c".  When that file became too big (over
+** 6000 lines long) it was split up into several smaller files and
+** this header information was factored out.
+*/
+#ifndef _VDBEINT_H_
+#define _VDBEINT_H_
+
+/*
+** SQL is translated into a sequence of instructions to be
+** executed by a virtual machine.  Each instruction is an instance
+** of the following structure.
+*/
+typedef struct VdbeOp Op;
+
+/*
+** Boolean values
+*/
+typedef unsigned char Bool;
+
+/*
+** A cursor is a pointer into a single BTree within a database file.
+** The cursor can seek to a BTree entry with a particular key, or
+** loop over all entries of the Btree.  You can also insert new BTree
+** entries or retrieve the key or data from the entry that the cursor
+** is currently pointing to.
+** 
+** Every cursor that the virtual machine has open is represented by an
+** instance of the following structure.
+**
+** If the VdbeCursor.isTriggerRow flag is set it means that this cursor is
+** really a single row that represents the NEW or OLD pseudo-table of
+** a row trigger.  The data for the row is stored in VdbeCursor.pData and
+** the rowid is in VdbeCursor.iKey.
+*/
+struct VdbeCursor {
+  BtCursor *pCursor;    /* The cursor structure of the backend */
+  int iDb;              /* Index of cursor database in db->aDb[] (or -1) */
+  i64 lastRowid;        /* Last rowid from a Next or NextIdx operation */
+  Bool zeroed;          /* True if zeroed out and ready for reuse */
+  Bool rowidIsValid;    /* True if lastRowid is valid */
+  Bool atFirst;         /* True if pointing to first entry */
+  Bool useRandomRowid;  /* Generate new record numbers semi-randomly */
+  Bool nullRow;         /* True if pointing to a row with no data */
+  Bool deferredMoveto;  /* A call to sqlite3BtreeMoveto() is needed */
+  Bool isTable;         /* True if a table requiring integer keys */
+  Bool isIndex;         /* True if an index containing keys only - no data */
+  Bool isOrdered;       /* True if the underlying table is BTREE_UNORDERED */
+  i64 movetoTarget;     /* Argument to the deferred sqlite3BtreeMoveto() */
+  Btree *pBt;           /* Separate file holding temporary table */
+  int pseudoTableReg;   /* Register holding pseudotable content. */
+  KeyInfo *pKeyInfo;    /* Info about index keys needed by index cursors */
+  int nField;           /* Number of fields in the header */
+  i64 seqCount;         /* Sequence counter */
+  sqlite3_vtab_cursor *pVtabCursor;  /* The cursor for a virtual table */
+  const sqlite3_module *pModule;     /* Module for cursor pVtabCursor */
+
+  /* Result of last sqlite3BtreeMoveto() done by an OP_NotExists or 
+  ** OP_IsUnique opcode on this cursor. */
+  int seekResult;
+
+  /* Cached information about the header for the data record that the
+  ** cursor is currently pointing to.  Only valid if cacheStatus matches
+  ** Vdbe.cacheCtr.  Vdbe.cacheCtr will never take on the value of
+  ** CACHE_STALE and so setting cacheStatus=CACHE_STALE guarantees that
+  ** the cache is out of date.
+  **
+  ** aRow might point to (ephemeral) data for the current row, or it might
+  ** be NULL.
+  */
+  u32 cacheStatus;      /* Cache is valid if this matches Vdbe.cacheCtr */
+  int payloadSize;      /* Total number of bytes in the record */
+  u32 *aType;           /* Type values for all entries in the record */
+  u32 *aOffset;         /* Cached offsets to the start of each columns data */
+  u8 *aRow;             /* Data for the current row, if all on one page */
+};
+typedef struct VdbeCursor VdbeCursor;
+
+/*
+** When a sub-program is executed (OP_Program), a structure of this type
+** is allocated to store the current value of the program counter, as
+** well as the current memory cell array and various other frame specific
+** values stored in the Vdbe struct. When the sub-program is finished, 
+** these values are copied back to the Vdbe from the VdbeFrame structure,
+** restoring the state of the VM to as it was before the sub-program
+** began executing.
+**
+** Frames are stored in a linked list headed at Vdbe.pParent. Vdbe.pParent
+** is the parent of the current frame, or zero if the current frame
+** is the main Vdbe program.
+*/
+typedef struct VdbeFrame VdbeFrame;
+struct VdbeFrame {
+  Vdbe *v;                /* VM this frame belongs to */
+  int pc;                 /* Program Counter */
+  Op *aOp;                /* Program instructions */
+  int nOp;                /* Size of aOp array */
+  Mem *aMem;              /* Array of memory cells */
+  int nMem;               /* Number of entries in aMem */
+  VdbeCursor **apCsr;     /* Element of Vdbe cursors */
+  u16 nCursor;            /* Number of entries in apCsr */
+  void *token;            /* Copy of SubProgram.token */
+  int nChildMem;          /* Number of memory cells for child frame */
+  int nChildCsr;          /* Number of cursors for child frame */
+  i64 lastRowid;          /* Last insert rowid (sqlite3.lastRowid) */
+  int nChange;            /* Statement changes (Vdbe.nChanges)     */
+  VdbeFrame *pParent;     /* Parent of this frame */
+};
+
+#define VdbeFrameMem(p) ((Mem *)&((u8 *)p)[ROUND8(sizeof(VdbeFrame))])
+
+/*
+** A value for VdbeCursor.cacheValid that means the cache is always invalid.
+*/
+#define CACHE_STALE 0
+
+/*
+** Internally, the vdbe manipulates nearly all SQL values as Mem
+** structures. Each Mem struct may cache multiple representations (string,
+** integer etc.) of the same value.  A value (and therefore Mem structure)
+** has the following properties:
+**
+** Each value has a manifest type. The manifest type of the value stored
+** in a Mem struct is returned by the MemType(Mem*) macro. The type is
+** one of SQLITE_NULL, SQLITE_INTEGER, SQLITE_REAL, SQLITE_TEXT or
+** SQLITE_BLOB.
+*/
+struct Mem {
+  union {
+    i64 i;              /* Integer value. */
+    int nZero;          /* Used when bit MEM_Zero is set in flags */
+    FuncDef *pDef;      /* Used only when flags==MEM_Agg */
+    RowSet *pRowSet;    /* Used only when flags==MEM_RowSet */
+    VdbeFrame *pFrame;  /* Used when flags==MEM_Frame */
+  } u;
+  double r;           /* Real value */
+  sqlite3 *db;        /* The associated database connection */
+  char *z;            /* String or BLOB value */
+  int n;              /* Number of characters in string value, excluding '\0' */
+  u16 flags;          /* Some combination of MEM_Null, MEM_Str, MEM_Dyn, etc. */
+  u8  type;           /* One of SQLITE_NULL, SQLITE_TEXT, SQLITE_INTEGER, etc */
+  u8  enc;            /* SQLITE_UTF8, SQLITE_UTF16BE, SQLITE_UTF16LE */
+#ifdef SQLITE_DEBUG
+  Mem *pScopyFrom;    /* This Mem is a shallow copy of pScopyFrom */
+  void *pFiller;      /* So that sizeof(Mem) is a multiple of 8 */
+#endif
+  void (*xDel)(void *);  /* If not null, call this function to delete Mem.z */
+  char *zMalloc;      /* Dynamic buffer allocated by sqlite3_malloc() */
+};
+
+/* One or more of the following flags are set to indicate the validOK
+** representations of the value stored in the Mem struct.
+**
+** If the MEM_Null flag is set, then the value is an SQL NULL value.
+** No other flags may be set in this case.
+**
+** If the MEM_Str flag is set then Mem.z points at a string representation.
+** Usually this is encoded in the same unicode encoding as the main
+** database (see below for exceptions). If the MEM_Term flag is also
+** set, then the string is nul terminated. The MEM_Int and MEM_Real 
+** flags may coexist with the MEM_Str flag.
+**
+** Multiple of these values can appear in Mem.flags.  But only one
+** at a time can appear in Mem.type.
+*/
+#define MEM_Null      0x0001   /* Value is NULL */
+#define MEM_Str       0x0002   /* Value is a string */
+#define MEM_Int       0x0004   /* Value is an integer */
+#define MEM_Real      0x0008   /* Value is a real number */
+#define MEM_Blob      0x0010   /* Value is a BLOB */
+#define MEM_RowSet    0x0020   /* Value is a RowSet object */
+#define MEM_Frame     0x0040   /* Value is a VdbeFrame object */
+#define MEM_Invalid   0x0080   /* Value is undefined */
+#define MEM_TypeMask  0x00ff   /* Mask of type bits */
+
+/* Whenever Mem contains a valid string or blob representation, one of
+** the following flags must be set to determine the memory management
+** policy for Mem.z.  The MEM_Term flag tells us whether or not the
+** string is \000 or \u0000 terminated
+*/
+#define MEM_Term      0x0200   /* String rep is nul terminated */
+#define MEM_Dyn       0x0400   /* Need to call sqliteFree() on Mem.z */
+#define MEM_Static    0x0800   /* Mem.z points to a static string */
+#define MEM_Ephem     0x1000   /* Mem.z points to an ephemeral string */
+#define MEM_Agg       0x2000   /* Mem.z points to an agg function context */
+#define MEM_Zero      0x4000   /* Mem.i contains count of 0s appended to blob */
+#ifdef SQLITE_OMIT_INCRBLOB
+  #undef MEM_Zero
+  #define MEM_Zero 0x0000
+#endif
+
+/*
+** Clear any existing type flags from a Mem and replace them with f
+*/
+#define MemSetTypeFlag(p, f) \
+   ((p)->flags = ((p)->flags&~(MEM_TypeMask|MEM_Zero))|f)
+
+/*
+** Return true if a memory cell is not marked as invalid.  This macro
+** is for use inside assert() statements only.
+*/
+#ifdef SQLITE_DEBUG
+#define memIsValid(M)  ((M)->flags & MEM_Invalid)==0
+#endif
+
+
+/* A VdbeFunc is just a FuncDef (defined in sqliteInt.h) that contains
+** additional information about auxiliary information bound to arguments
+** of the function.  This is used to implement the sqlite3_get_auxdata()
+** and sqlite3_set_auxdata() APIs.  The "auxdata" is some auxiliary data
+** that can be associated with a constant argument to a function.  This
+** allows functions such as "regexp" to compile their constant regular
+** expression argument once and reused the compiled code for multiple
+** invocations.
+*/
+struct VdbeFunc {
+  FuncDef *pFunc;               /* The definition of the function */
+  int nAux;                     /* Number of entries allocated for apAux[] */
+  struct AuxData {
+    void *pAux;                   /* Aux data for the i-th argument */
+    void (*xDelete)(void *);      /* Destructor for the aux data */
+  } apAux[1];                   /* One slot for each function argument */
+};
+
+/*
+** The "context" argument for a installable function.  A pointer to an
+** instance of this structure is the first argument to the routines used
+** implement the SQL functions.
+**
+** There is a typedef for this structure in sqlite.h.  So all routines,
+** even the public interface to SQLite, can use a pointer to this structure.
+** But this file is the only place where the internal details of this
+** structure are known.
+**
+** This structure is defined inside of vdbeInt.h because it uses substructures
+** (Mem) which are only defined there.
+*/
+struct sqlite3_context {
+  FuncDef *pFunc;       /* Pointer to function information.  MUST BE FIRST */
+  VdbeFunc *pVdbeFunc;  /* Auxilary data, if created. */
+  Mem s;                /* The return value is stored here */
+  Mem *pMem;            /* Memory cell used to store aggregate context */
+  int isError;          /* Error code returned by the function. */
+  CollSeq *pColl;       /* Collating sequence */
+};
+
+/*
+** A Set structure is used for quick testing to see if a value
+** is part of a small set.  Sets are used to implement code like
+** this:
+**            x.y IN ('hi','hoo','hum')
+*/
+typedef struct Set Set;
+struct Set {
+  Hash hash;             /* A set is just a hash table */
+  HashElem *prev;        /* Previously accessed hash elemen */
+};
+
+/*
+** An instance of the virtual machine.  This structure contains the complete
+** state of the virtual machine.
+**
+** The "sqlite3_stmt" structure pointer that is returned by sqlite3_compile()
+** is really a pointer to an instance of this structure.
+**
+** The Vdbe.inVtabMethod variable is set to non-zero for the duration of
+** any virtual table method invocations made by the vdbe program. It is
+** set to 2 for xDestroy method calls and 1 for all other methods. This
+** variable is used for two purposes: to allow xDestroy methods to execute
+** "DROP TABLE" statements and to prevent some nasty side effects of
+** malloc failure when SQLite is invoked recursively by a virtual table 
+** method function.
+*/
+struct Vdbe {
+  sqlite3 *db;            /* The database connection that owns this statement */
+  Vdbe *pPrev,*pNext;     /* Linked list of VDBEs with the same Vdbe.db */
+  int nOp;                /* Number of instructions in the program */
+  int nOpAlloc;           /* Number of slots allocated for aOp[] */
+  Op *aOp;                /* Space to hold the virtual machine's program */
+  int nLabel;             /* Number of labels used */
+  int nLabelAlloc;        /* Number of slots allocated in aLabel[] */
+  int *aLabel;            /* Space to hold the labels */
+  Mem **apArg;            /* Arguments to currently executing user function */
+  Mem *aColName;          /* Column names to return */
+  Mem *pResultSet;        /* Pointer to an array of results */
+  u16 nResColumn;         /* Number of columns in one row of the result set */
+  u16 nCursor;            /* Number of slots in apCsr[] */
+  VdbeCursor **apCsr;     /* One element of this array for each open cursor */
+  u8 errorAction;         /* Recovery action to do in case of an error */
+  u8 okVar;               /* True if azVar[] has been initialized */
+  ynVar nVar;             /* Number of entries in aVar[] */
+  Mem *aVar;              /* Values for the OP_Variable opcode. */
+  char **azVar;           /* Name of variables */
+  u32 magic;              /* Magic number for sanity checking */
+  int nMem;               /* Number of memory locations currently allocated */
+  Mem *aMem;              /* The memory locations */
+  u32 cacheCtr;           /* VdbeCursor row cache generation counter */
+  int pc;                 /* The program counter */
+  int rc;                 /* Value to return */
+  char *zErrMsg;          /* Error message written here */
+  u8 explain;             /* True if EXPLAIN present on SQL command */
+  u8 changeCntOn;         /* True to update the change-counter */
+  u8 expired;             /* True if the VM needs to be recompiled */
+  u8 runOnlyOnce;         /* Automatically expire on reset */
+  u8 minWriteFileFormat;  /* Minimum file format for writable database files */
+  u8 inVtabMethod;        /* See comments above */
+  u8 usesStmtJournal;     /* True if uses a statement journal */
+  u8 readOnly;            /* True for read-only statements */
+  u8 isPrepareV2;         /* True if prepared with prepare_v2() */
+  int nChange;            /* Number of db changes made since last reset */
+  int btreeMask;          /* Bitmask of db->aDb[] entries referenced */
+  i64 startTime;          /* Time when query started - used for profiling */
+  BtreeMutexArray aMutex; /* An array of Btree used here and needing locks */
+  int aCounter[3];        /* Counters used by sqlite3_stmt_status() */
+  char *zSql;             /* Text of the SQL statement that generated this */
+  void *pFree;            /* Free this when deleting the vdbe */
+  i64 nFkConstraint;      /* Number of imm. FK constraints this VM */
+  i64 nStmtDefCons;       /* Number of def. constraints when stmt started */
+  int iStatement;         /* Statement number (or 0 if has not opened stmt) */
+#ifdef SQLITE_DEBUG
+  FILE *trace;            /* Write an execution trace here, if not NULL */
+#endif
+  VdbeFrame *pFrame;      /* Parent frame */
+  int nFrame;             /* Number of frames in pFrame list */
+  u32 expmask;            /* Binding to these vars invalidates VM */
+  SubProgram *pProgram;   /* Linked list of all sub-programs used by VM */
+};
+
+/*
+** The following are allowed values for Vdbe.magic
+*/
+#define VDBE_MAGIC_INIT     0x26bceaa5    /* Building a VDBE program */
+#define VDBE_MAGIC_RUN      0xbdf20da3    /* VDBE is ready to execute */
+#define VDBE_MAGIC_HALT     0x519c2973    /* VDBE has completed execution */
+#define VDBE_MAGIC_DEAD     0xb606c3c8    /* The VDBE has been deallocated */
+
+/*
+** Function prototypes
+*/
+SQLITE_PRIVATE void sqlite3VdbeFreeCursor(Vdbe *, VdbeCursor*);
+void sqliteVdbePopStack(Vdbe*,int);
+SQLITE_PRIVATE int sqlite3VdbeCursorMoveto(VdbeCursor*);
+#if defined(SQLITE_DEBUG) || defined(VDBE_PROFILE)
+SQLITE_PRIVATE void sqlite3VdbePrintOp(FILE*, int, Op*);
+#endif
+SQLITE_PRIVATE u32 sqlite3VdbeSerialTypeLen(u32);
+SQLITE_PRIVATE u32 sqlite3VdbeSerialType(Mem*, int);
+SQLITE_PRIVATE u32 sqlite3VdbeSerialPut(unsigned char*, int, Mem*, int);
+SQLITE_PRIVATE u32 sqlite3VdbeSerialGet(const unsigned char*, u32, Mem*);
+SQLITE_PRIVATE void sqlite3VdbeDeleteAuxData(VdbeFunc*, int);
+
+int sqlite2BtreeKeyCompare(BtCursor *, const void *, int, int, int *);
+SQLITE_PRIVATE int sqlite3VdbeIdxKeyCompare(VdbeCursor*,UnpackedRecord*,int*);
+SQLITE_PRIVATE int sqlite3VdbeIdxRowid(sqlite3*, BtCursor *, i64 *);
+SQLITE_PRIVATE int sqlite3MemCompare(const Mem*, const Mem*, const CollSeq*);
+SQLITE_PRIVATE int sqlite3VdbeExec(Vdbe*);
+SQLITE_PRIVATE int sqlite3VdbeList(Vdbe*);
+SQLITE_PRIVATE int sqlite3VdbeHalt(Vdbe*);
+SQLITE_PRIVATE int sqlite3VdbeChangeEncoding(Mem *, int);
+SQLITE_PRIVATE int sqlite3VdbeMemTooBig(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemCopy(Mem*, const Mem*);
+SQLITE_PRIVATE void sqlite3VdbeMemShallowCopy(Mem*, const Mem*, int);
+SQLITE_PRIVATE void sqlite3VdbeMemMove(Mem*, Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemNulTerminate(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemSetStr(Mem*, const char*, int, u8, void(*)(void*));
+SQLITE_PRIVATE void sqlite3VdbeMemSetInt64(Mem*, i64);
+#ifdef SQLITE_OMIT_FLOATING_POINT
+# define sqlite3VdbeMemSetDouble sqlite3VdbeMemSetInt64
+#else
+SQLITE_PRIVATE   void sqlite3VdbeMemSetDouble(Mem*, double);
+#endif
+SQLITE_PRIVATE void sqlite3VdbeMemSetNull(Mem*);
+SQLITE_PRIVATE void sqlite3VdbeMemSetZeroBlob(Mem*,int);
+SQLITE_PRIVATE void sqlite3VdbeMemSetRowSet(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemMakeWriteable(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemStringify(Mem*, int);
+SQLITE_PRIVATE i64 sqlite3VdbeIntValue(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemIntegerify(Mem*);
+SQLITE_PRIVATE double sqlite3VdbeRealValue(Mem*);
+SQLITE_PRIVATE void sqlite3VdbeIntegerAffinity(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemRealify(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemNumerify(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemFromBtree(BtCursor*,int,int,int,Mem*);
+SQLITE_PRIVATE void sqlite3VdbeMemRelease(Mem *p);
+SQLITE_PRIVATE void sqlite3VdbeMemReleaseExternal(Mem *p);
+SQLITE_PRIVATE int sqlite3VdbeMemFinalize(Mem*, FuncDef*);
+SQLITE_PRIVATE const char *sqlite3OpcodeName(int);
+SQLITE_PRIVATE int sqlite3VdbeMemGrow(Mem *pMem, int n, int preserve);
+SQLITE_PRIVATE int sqlite3VdbeCloseStatement(Vdbe *, int);
+SQLITE_PRIVATE void sqlite3VdbeFrameDelete(VdbeFrame*);
+SQLITE_PRIVATE int sqlite3VdbeFrameRestore(VdbeFrame *);
+SQLITE_PRIVATE void sqlite3VdbeMemStoreType(Mem *pMem);
+
+#ifdef SQLITE_DEBUG
+SQLITE_PRIVATE void sqlite3VdbeMemPrepareToChange(Vdbe*,Mem*);
+#endif
+
+#ifndef SQLITE_OMIT_FOREIGN_KEY
+SQLITE_PRIVATE int sqlite3VdbeCheckFk(Vdbe *, int);
+#else
+# define sqlite3VdbeCheckFk(p,i) 0
+#endif
+
+#ifndef SQLITE_OMIT_SHARED_CACHE
+SQLITE_PRIVATE void sqlite3VdbeMutexArrayEnter(Vdbe *p);
+#else
+# define sqlite3VdbeMutexArrayEnter(p)
+#endif
+
+SQLITE_PRIVATE int sqlite3VdbeMemTranslate(Mem*, u8);
+#ifdef SQLITE_DEBUG
+SQLITE_PRIVATE   void sqlite3VdbePrintSql(Vdbe*);
+SQLITE_PRIVATE   void sqlite3VdbeMemPrettyPrint(Mem *pMem, char *zBuf);
+#endif
+SQLITE_PRIVATE int sqlite3VdbeMemHandleBom(Mem *pMem);
+
+#ifndef SQLITE_OMIT_INCRBLOB
+SQLITE_PRIVATE   int sqlite3VdbeMemExpandBlob(Mem *);
+#else
+  #define sqlite3VdbeMemExpandBlob(x) SQLITE_OK
+#endif
+
+#endif /* !defined(_VDBEINT_H_) */
+
+/************** End of vdbeInt.h *********************************************/
+/************** Continuing where we left off in status.c *********************/
 
 /*
 ** Variables in which to record status information.
 */
 typedef struct sqlite3StatType sqlite3StatType;
 static SQLITE_WSD struct sqlite3StatType {
-  int nowValue[9];         /* Current value */
-  int mxValue[9];          /* Maximum value */
+  int nowValue[10];         /* Current value */
+  int mxValue[10];          /* Maximum value */
 } sqlite3Stat = { {0,}, {0,} };
 
 
@@ -11647,6 +12396,8 @@
   int *pHighwater,      /* Write high-water mark here */
   int resetFlag         /* Reset high-water mark if true */
 ){
+  int rc = SQLITE_OK;   /* Return code */
+  sqlite3_mutex_enter(db->mutex);
   switch( op ){
     case SQLITE_DBSTATUS_LOOKASIDE_USED: {
       *pCurrent = db->lookaside.nOut;
@@ -11665,6 +12416,7 @@
     case SQLITE_DBSTATUS_CACHE_USED: {
       int totalUsed = 0;
       int i;
+      sqlite3BtreeEnterAll(db);
       for(i=0; i<db->nDb; i++){
         Btree *pBt = db->aDb[i].pBt;
         if( pBt ){
@@ -11672,15 +12424,80 @@
           totalUsed += sqlite3PagerMemUsed(pPager);
         }
       }
+      sqlite3BtreeLeaveAll(db);
       *pCurrent = totalUsed;
       *pHighwater = 0;
       break;
     }
+
+    /*
+    ** *pCurrent gets an accurate estimate of the amount of memory used
+    ** to store the schema for all databases (main, temp, and any ATTACHed
+    ** databases.  *pHighwater is set to zero.
+    */
+    case SQLITE_DBSTATUS_SCHEMA_USED: {
+      int i;                      /* Used to iterate through schemas */
+      int nByte = 0;              /* Used to accumulate return value */
+
+      db->pnBytesFreed = &nByte;
+      for(i=0; i<db->nDb; i++){
+        Schema *pSchema = db->aDb[i].pSchema;
+        if( ALWAYS(pSchema!=0) ){
+          HashElem *p;
+
+          nByte += sqlite3GlobalConfig.m.xRoundup(sizeof(HashElem)) * (
+              pSchema->tblHash.count 
+            + pSchema->trigHash.count
+            + pSchema->idxHash.count
+            + pSchema->fkeyHash.count
+          );
+          nByte += sqlite3MallocSize(pSchema->tblHash.ht);
+          nByte += sqlite3MallocSize(pSchema->trigHash.ht);
+          nByte += sqlite3MallocSize(pSchema->idxHash.ht);
+          nByte += sqlite3MallocSize(pSchema->fkeyHash.ht);
+
+          for(p=sqliteHashFirst(&pSchema->trigHash); p; p=sqliteHashNext(p)){
+            sqlite3DeleteTrigger(db, (Trigger*)sqliteHashData(p));
+          }
+          for(p=sqliteHashFirst(&pSchema->tblHash); p; p=sqliteHashNext(p)){
+            sqlite3DeleteTable(db, (Table *)sqliteHashData(p));
+          }
+        }
+      }
+      db->pnBytesFreed = 0;
+
+      *pHighwater = 0;
+      *pCurrent = nByte;
+      break;
+    }
+
+    /*
+    ** *pCurrent gets an accurate estimate of the amount of memory used
+    ** to store all prepared statements.
+    ** *pHighwater is set to zero.
+    */
+    case SQLITE_DBSTATUS_STMT_USED: {
+      struct Vdbe *pVdbe;         /* Used to iterate through VMs */
+      int nByte = 0;              /* Used to accumulate return value */
+
+      db->pnBytesFreed = &nByte;
+      for(pVdbe=db->pVdbe; pVdbe; pVdbe=pVdbe->pNext){
+        sqlite3VdbeDeleteObject(db, pVdbe);
+      }
+      db->pnBytesFreed = 0;
+
+      *pHighwater = 0;
+      *pCurrent = nByte;
+
+      break;
+    }
+
     default: {
-      return SQLITE_ERROR;
+      rc = SQLITE_ERROR;
     }
   }
-  return SQLITE_OK;
+  sqlite3_mutex_leave(db->mutex);
+  return rc;
 }
 
 /************** End of status.c **********************************************/
@@ -12883,26 +13700,23 @@
 SQLITE_PRIVATE int sqlite3OsDeviceCharacteristics(sqlite3_file *id){
   return id->pMethods->xDeviceCharacteristics(id);
 }
-SQLITE_PRIVATE int sqlite3OsShmOpen(sqlite3_file *id){
-  return id->pMethods->xShmOpen(id);
-}
 SQLITE_PRIVATE int sqlite3OsShmLock(sqlite3_file *id, int offset, int n, int flags){
   return id->pMethods->xShmLock(id, offset, n, flags);
 }
 SQLITE_PRIVATE void sqlite3OsShmBarrier(sqlite3_file *id){
   id->pMethods->xShmBarrier(id);
 }
-SQLITE_PRIVATE int sqlite3OsShmClose(sqlite3_file *id, int deleteFlag){
-  return id->pMethods->xShmClose(id, deleteFlag);
+SQLITE_PRIVATE int sqlite3OsShmUnmap(sqlite3_file *id, int deleteFlag){
+  return id->pMethods->xShmUnmap(id, deleteFlag);
 }
 SQLITE_PRIVATE int sqlite3OsShmMap(
-  sqlite3_file *id, 
-  int iPage, 
-  int pgsz, 
-  int isWrite, 
-  void volatile **pp
+  sqlite3_file *id,               /* Database file handle */
+  int iPage,
+  int pgsz,
+  int bExtend,                    /* True to extend file if necessary */
+  void volatile **pp              /* OUT: Pointer to mapping */
 ){
-  return id->pMethods->xShmMap(id, iPage, pgsz, isWrite, pp);
+  return id->pMethods->xShmMap(id, iPage, pgsz, bExtend, pp);
 }
 
 /*
@@ -12918,11 +13732,11 @@
 ){
   int rc;
   DO_OS_MALLOC_TEST(0);
-  /* 0x7f3f is a mask of SQLITE_OPEN_ flags that are valid to be passed
+  /* 0x87f3f is a mask of SQLITE_OPEN_ flags that are valid to be passed
   ** down into the VFS layer.  Some SQLITE_OPEN_ flags (for example,
   ** SQLITE_OPEN_FULLMUTEX or SQLITE_OPEN_SHAREDCACHE) are blocked before
   ** reaching the VFS. */
-  rc = pVfs->xOpen(pVfs, zPath, pFile, flags & 0x7f3f, pFlagsOut);
+  rc = pVfs->xOpen(pVfs, zPath, pFile, flags & 0x87f3f, pFlagsOut);
   assert( rc==SQLITE_OK || pFile->pMethods==0 );
   return rc;
 }
@@ -12969,6 +13783,12 @@
 }
 SQLITE_PRIVATE int sqlite3OsCurrentTimeInt64(sqlite3_vfs *pVfs, sqlite3_int64 *pTimeOut){
   int rc;
+  /* IMPLEMENTATION-OF: R-49045-42493 SQLite will use the xCurrentTimeInt64()
+  ** method to get the current date and time if that method is available
+  ** (if iVersion is 2 or greater and the function pointer is not NULL) and
+  ** will fall back to xCurrentTime() if xCurrentTimeInt64() is
+  ** unavailable.
+  */
   if( pVfs->iVersion>=2 && pVfs->xCurrentTimeInt64 ){
     rc = pVfs->xCurrentTimeInt64(pVfs, pTimeOut);
   }else{
@@ -13352,7 +14172,7 @@
 static void *sqlite3MemRealloc(void *pPrior, int nByte){
   sqlite3_int64 *p = (sqlite3_int64*)pPrior;
   assert( pPrior!=0 && nByte>0 );
-  nByte = ROUND8(nByte);
+  assert( nByte==ROUND8(nByte) ); /* EV: R-46199-30249 */
   p--;
   p = realloc(p, nByte+8 );
   if( p ){
@@ -13758,6 +14578,7 @@
   struct MemBlockHdr *pOldHdr;
   void *pNew;
   assert( mem.disallow==0 );
+  assert( (nByte & 7)==0 );     /* EV: R-46199-30249 */
   pOldHdr = sqlite3MemsysGetHeader(pPrior);
   pNew = sqlite3MemMalloc(nByte);
   if( pNew ){
@@ -13792,7 +14613,7 @@
 ** Set the "type" of an allocation.
 */
 SQLITE_PRIVATE void sqlite3MemdebugSetType(void *p, u8 eType){
-  if( p ){
+  if( p && sqlite3GlobalConfig.m.xMalloc==sqlite3MemMalloc ){
     struct MemBlockHdr *pHdr;
     pHdr = sqlite3MemsysGetHeader(p);
     assert( pHdr->iForeGuard==FOREGUARD );
@@ -13811,23 +14632,38 @@
 */
 SQLITE_PRIVATE int sqlite3MemdebugHasType(void *p, u8 eType){
   int rc = 1;
-  if( p ){
+  if( p && sqlite3GlobalConfig.m.xMalloc==sqlite3MemMalloc ){
     struct MemBlockHdr *pHdr;
     pHdr = sqlite3MemsysGetHeader(p);
     assert( pHdr->iForeGuard==FOREGUARD );         /* Allocation is valid */
-    assert( (pHdr->eType & (pHdr->eType-1))==0 );  /* Only one type bit set */
     if( (pHdr->eType&eType)==0 ){
-      void **pBt;
-      pBt = (void**)pHdr;
-      pBt -= pHdr->nBacktraceSlots;
-      backtrace_symbols_fd(pBt, pHdr->nBacktrace, fileno(stderr));
-      fprintf(stderr, "\n");
       rc = 0;
     }
   }
   return rc;
 }
- 
+
+/*
+** Return TRUE if the mask of type in eType matches no bits of the type of the
+** allocation p.  Also return true if p==NULL.
+**
+** This routine is designed for use within an assert() statement, to
+** verify the type of an allocation.  For example:
+**
+**     assert( sqlite3MemdebugNoType(p, MEMTYPE_DB) );
+*/
+SQLITE_PRIVATE int sqlite3MemdebugNoType(void *p, u8 eType){
+  int rc = 1;
+  if( p && sqlite3GlobalConfig.m.xMalloc==sqlite3MemMalloc ){
+    struct MemBlockHdr *pHdr;
+    pHdr = sqlite3MemsysGetHeader(p);
+    assert( pHdr->iForeGuard==FOREGUARD );         /* Allocation is valid */
+    if( (pHdr->eType&eType)!=0 ){
+      rc = 0;
+    }
+  }
+  return rc;
+}
 
 /*
 ** Set the number of backtrace levels kept for each allocation.
@@ -15012,7 +15848,7 @@
   int nOld;
   void *p;
   assert( pPrior!=0 );
-  assert( (nBytes&(nBytes-1))==0 );
+  assert( (nBytes&(nBytes-1))==0 );  /* EV: R-46199-30249 */
   assert( nBytes>=0 );
   if( nBytes==0 ){
     return 0;
@@ -16070,6 +16906,7 @@
   */
   pthread_mutex_lock(&p->mutex);
 #if SQLITE_MUTEX_NREF
+  assert( p->nRef>0 || p->owner==0 );
   p->owner = pthread_self();
   p->nRef++;
 #endif
@@ -16142,6 +16979,7 @@
   assert( pthreadMutexHeld(p) );
 #if SQLITE_MUTEX_NREF
   p->nRef--;
+  if( p->nRef==0 ) p->owner = 0;
 #endif
   assert( p->nRef==0 || p->id==SQLITE_MUTEX_RECURSIVE );
 
@@ -16406,7 +17244,7 @@
 */
 static void winMutexFree(sqlite3_mutex *p){
   assert( p );
-  assert( p->nRef==0 );
+  assert( p->nRef==0 && p->owner==0 );
   assert( p->id==SQLITE_MUTEX_FAST || p->id==SQLITE_MUTEX_RECURSIVE );
   DeleteCriticalSection(&p->mutex);
   sqlite3_free(p);
@@ -16430,6 +17268,7 @@
 #endif
   EnterCriticalSection(&p->mutex);
 #ifdef SQLITE_DEBUG
+  assert( p->nRef>0 || p->owner==0 );
   p->owner = tid; 
   p->nRef++;
   if( p->trace ){
@@ -16483,6 +17322,7 @@
   assert( p->nRef>0 );
   assert( p->owner==tid );
   p->nRef--;
+  if( p->nRef==0 ) p->owner = 0;
   assert( p->nRef==0 || p->id==SQLITE_MUTEX_RECURSIVE );
 #endif
   LeaveCriticalSection(&p->mutex);
@@ -16533,6 +17373,66 @@
 */
 
 /*
+** Attempt to release up to n bytes of non-essential memory currently
+** held by SQLite. An example of non-essential memory is memory used to
+** cache database pages that are not currently in use.
+*/
+SQLITE_API int sqlite3_release_memory(int n){
+#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
+  return sqlite3PcacheReleaseMemory(n);
+#else
+  /* IMPLEMENTATION-OF: R-34391-24921 The sqlite3_release_memory() routine
+  ** is a no-op returning zero if SQLite is not compiled with
+  ** SQLITE_ENABLE_MEMORY_MANAGEMENT. */
+  UNUSED_PARAMETER(n);
+  return 0;
+#endif
+}
+
+/*
+** An instance of the following object records the location of
+** each unused scratch buffer.
+*/
+typedef struct ScratchFreeslot {
+  struct ScratchFreeslot *pNext;   /* Next unused scratch buffer */
+} ScratchFreeslot;
+
+/*
+** State information local to the memory allocation subsystem.
+*/
+static SQLITE_WSD struct Mem0Global {
+  sqlite3_mutex *mutex;         /* Mutex to serialize access */
+
+  /*
+  ** The alarm callback and its arguments.  The mem0.mutex lock will
+  ** be held while the callback is running.  Recursive calls into
+  ** the memory subsystem are allowed, but no new callbacks will be
+  ** issued.
+  */
+  sqlite3_int64 alarmThreshold;
+  void (*alarmCallback)(void*, sqlite3_int64,int);
+  void *alarmArg;
+
+  /*
+  ** Pointers to the end of sqlite3GlobalConfig.pScratch memory
+  ** (so that a range test can be used to determine if an allocation
+  ** being freed came from pScratch) and a pointer to the list of
+  ** unused scratch allocations.
+  */
+  void *pScratchEnd;
+  ScratchFreeslot *pScratchFree;
+  u32 nScratchFree;
+
+  /*
+  ** True if heap is nearly "full" where "full" is defined by the
+  ** sqlite3_soft_heap_limit() setting.
+  */
+  int nearlyFull;
+} mem0 = { 0, 0, 0, 0, 0, 0, 0 };
+
+#define mem0 GLOBAL(struct Mem0Global, mem0)
+
+/*
 ** This routine runs when the memory allocator sees that the
 ** total memory allocation is about to exceed the soft heap
 ** limit.
@@ -16547,79 +17447,67 @@
 }
 
 /*
+** Change the alarm callback
+*/
+static int sqlite3MemoryAlarm(
+  void(*xCallback)(void *pArg, sqlite3_int64 used,int N),
+  void *pArg,
+  sqlite3_int64 iThreshold
+){
+  int nUsed;
+  sqlite3_mutex_enter(mem0.mutex);
+  mem0.alarmCallback = xCallback;
+  mem0.alarmArg = pArg;
+  mem0.alarmThreshold = iThreshold;
+  nUsed = sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED);
+  mem0.nearlyFull = (iThreshold>0 && iThreshold<=nUsed);
+  sqlite3_mutex_leave(mem0.mutex);
+  return SQLITE_OK;
+}
+
+#ifndef SQLITE_OMIT_DEPRECATED
+/*
+** Deprecated external interface.  Internal/core SQLite code
+** should call sqlite3MemoryAlarm.
+*/
+SQLITE_API int sqlite3_memory_alarm(
+  void(*xCallback)(void *pArg, sqlite3_int64 used,int N),
+  void *pArg,
+  sqlite3_int64 iThreshold
+){
+  return sqlite3MemoryAlarm(xCallback, pArg, iThreshold);
+}
+#endif
+
+/*
 ** Set the soft heap-size limit for the library. Passing a zero or 
 ** negative value indicates no limit.
 */
-SQLITE_API void sqlite3_soft_heap_limit(int n){
-  sqlite3_uint64 iLimit;
-  int overage;
-  if( n<0 ){
-    iLimit = 0;
-  }else{
-    iLimit = n;
-  }
+SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 n){
+  sqlite3_int64 priorLimit;
+  sqlite3_int64 excess;
 #ifndef SQLITE_OMIT_AUTOINIT
   sqlite3_initialize();
 #endif
-  if( iLimit>0 ){
-    sqlite3MemoryAlarm(softHeapLimitEnforcer, 0, iLimit);
+  sqlite3_mutex_enter(mem0.mutex);
+  priorLimit = mem0.alarmThreshold;
+  sqlite3_mutex_leave(mem0.mutex);
+  if( n<0 ) return priorLimit;
+  if( n>0 ){
+    sqlite3MemoryAlarm(softHeapLimitEnforcer, 0, n);
   }else{
     sqlite3MemoryAlarm(0, 0, 0);
   }
-  overage = (int)(sqlite3_memory_used() - (i64)n);
-  if( overage>0 ){
-    sqlite3_release_memory(overage);
-  }
+  excess = sqlite3_memory_used() - n;
+  if( excess>0 ) sqlite3_release_memory(excess & 0x7fffffff);
+  return priorLimit;
 }
-
-/*
-** Attempt to release up to n bytes of non-essential memory currently
-** held by SQLite. An example of non-essential memory is memory used to
-** cache database pages that are not currently in use.
-*/
-SQLITE_API int sqlite3_release_memory(int n){
-#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
-  int nRet = 0;
-  nRet += sqlite3PcacheReleaseMemory(n-nRet);
-  return nRet;
-#else
-  UNUSED_PARAMETER(n);
-  return SQLITE_OK;
-#endif
+SQLITE_API void sqlite3_soft_heap_limit(int n){
+  if( n<0 ) n = 0;
+  sqlite3_soft_heap_limit64(n);
 }
 
 /*
-** State information local to the memory allocation subsystem.
-*/
-static SQLITE_WSD struct Mem0Global {
-  /* Number of free pages for scratch and page-cache memory */
-  u32 nScratchFree;
-  u32 nPageFree;
-
-  sqlite3_mutex *mutex;         /* Mutex to serialize access */
-
-  /*
-  ** The alarm callback and its arguments.  The mem0.mutex lock will
-  ** be held while the callback is running.  Recursive calls into
-  ** the memory subsystem are allowed, but no new callbacks will be
-  ** issued.
-  */
-  sqlite3_int64 alarmThreshold;
-  void (*alarmCallback)(void*, sqlite3_int64,int);
-  void *alarmArg;
-
-  /*
-  ** Pointers to the end of sqlite3GlobalConfig.pScratch and
-  ** sqlite3GlobalConfig.pPage to a block of memory that records
-  ** which pages are available.
-  */
-  u32 *aScratchFree;
-  u32 *aPageFree;
-} mem0 = { 0, 0, 0, 0, 0, 0, 0, 0 };
-
-#define mem0 GLOBAL(struct Mem0Global, mem0)
-
-/*
 ** Initialize the memory allocation subsystem.
 */
 SQLITE_PRIVATE int sqlite3MallocInit(void){
@@ -16631,37 +17519,46 @@
     mem0.mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MEM);
   }
   if( sqlite3GlobalConfig.pScratch && sqlite3GlobalConfig.szScratch>=100
-      && sqlite3GlobalConfig.nScratch>=0 ){
-    int i;
-    sqlite3GlobalConfig.szScratch = ROUNDDOWN8(sqlite3GlobalConfig.szScratch-4);
-    mem0.aScratchFree = (u32*)&((char*)sqlite3GlobalConfig.pScratch)
-                  [sqlite3GlobalConfig.szScratch*sqlite3GlobalConfig.nScratch];
-    for(i=0; i<sqlite3GlobalConfig.nScratch; i++){ mem0.aScratchFree[i] = i; }
-    mem0.nScratchFree = sqlite3GlobalConfig.nScratch;
+      && sqlite3GlobalConfig.nScratch>0 ){
+    int i, n, sz;
+    ScratchFreeslot *pSlot;
+    sz = ROUNDDOWN8(sqlite3GlobalConfig.szScratch);
+    sqlite3GlobalConfig.szScratch = sz;
+    pSlot = (ScratchFreeslot*)sqlite3GlobalConfig.pScratch;
+    n = sqlite3GlobalConfig.nScratch;
+    mem0.pScratchFree = pSlot;
+    mem0.nScratchFree = n;
+    for(i=0; i<n-1; i++){
+      pSlot->pNext = (ScratchFreeslot*)(sz+(char*)pSlot);
+      pSlot = pSlot->pNext;
+    }
+    pSlot->pNext = 0;
+    mem0.pScratchEnd = (void*)&pSlot[1];
   }else{
+    mem0.pScratchEnd = 0;
     sqlite3GlobalConfig.pScratch = 0;
     sqlite3GlobalConfig.szScratch = 0;
+    sqlite3GlobalConfig.nScratch = 0;
   }
-  if( sqlite3GlobalConfig.pPage && sqlite3GlobalConfig.szPage>=512
-      && sqlite3GlobalConfig.nPage>=1 ){
-    int i;
-    int overhead;
-    int sz = ROUNDDOWN8(sqlite3GlobalConfig.szPage);
-    int n = sqlite3GlobalConfig.nPage;
-    overhead = (4*n + sz - 1)/sz;
-    sqlite3GlobalConfig.nPage -= overhead;
-    mem0.aPageFree = (u32*)&((char*)sqlite3GlobalConfig.pPage)
-                  [sqlite3GlobalConfig.szPage*sqlite3GlobalConfig.nPage];
-    for(i=0; i<sqlite3GlobalConfig.nPage; i++){ mem0.aPageFree[i] = i; }
-    mem0.nPageFree = sqlite3GlobalConfig.nPage;
-  }else{
+  if( sqlite3GlobalConfig.pPage==0 || sqlite3GlobalConfig.szPage<512
+      || sqlite3GlobalConfig.nPage<1 ){
     sqlite3GlobalConfig.pPage = 0;
     sqlite3GlobalConfig.szPage = 0;
+    sqlite3GlobalConfig.nPage = 0;
   }
   return sqlite3GlobalConfig.m.xInit(sqlite3GlobalConfig.m.pAppData);
 }
 
 /*
+** Return true if the heap is currently under memory pressure - in other
+** words if the amount of heap used is close to the limit set by
+** sqlite3_soft_heap_limit().
+*/
+SQLITE_PRIVATE int sqlite3HeapNearlyFull(void){
+  return mem0.nearlyFull;
+}
+
+/*
 ** Deinitialize the memory allocation subsystem.
 */
 SQLITE_PRIVATE void sqlite3MallocEnd(void){
@@ -16696,36 +17593,6 @@
 }
 
 /*
-** Change the alarm callback
-*/
-SQLITE_PRIVATE int sqlite3MemoryAlarm(
-  void(*xCallback)(void *pArg, sqlite3_int64 used,int N),
-  void *pArg,
-  sqlite3_int64 iThreshold
-){
-  sqlite3_mutex_enter(mem0.mutex);
-  mem0.alarmCallback = xCallback;
-  mem0.alarmArg = pArg;
-  mem0.alarmThreshold = iThreshold;
-  sqlite3_mutex_leave(mem0.mutex);
-  return SQLITE_OK;
-}
-
-#ifndef SQLITE_OMIT_DEPRECATED
-/*
-** Deprecated external interface.  Internal/core SQLite code
-** should call sqlite3MemoryAlarm.
-*/
-SQLITE_API int sqlite3_memory_alarm(
-  void(*xCallback)(void *pArg, sqlite3_int64 used,int N),
-  void *pArg,
-  sqlite3_int64 iThreshold
-){
-  return sqlite3MemoryAlarm(xCallback, pArg, iThreshold);
-}
-#endif
-
-/*
 ** Trigger the alarm 
 */
 static void sqlite3MallocAlarm(int nByte){
@@ -16757,17 +17624,23 @@
   if( mem0.alarmCallback!=0 ){
     int nUsed = sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED);
     if( nUsed+nFull >= mem0.alarmThreshold ){
+      mem0.nearlyFull = 1;
       sqlite3MallocAlarm(nFull);
+    }else{
+      mem0.nearlyFull = 0;
     }
   }
   p = sqlite3GlobalConfig.m.xMalloc(nFull);
+#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
   if( p==0 && mem0.alarmCallback ){
     sqlite3MallocAlarm(nFull);
     p = sqlite3GlobalConfig.m.xMalloc(nFull);
   }
+#endif
   if( p ){
     nFull = sqlite3MallocSize(p);
     sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, nFull);
+    sqlite3StatusAdd(SQLITE_STATUS_MALLOC_COUNT, 1);
   }
   *pp = p;
   return nFull;
@@ -16779,7 +17652,9 @@
 */
 SQLITE_PRIVATE void *sqlite3Malloc(int n){
   void *p;
-  if( n<=0 || n>=0x7fffff00 ){
+  if( n<=0               /* IMP: R-65312-04917 */ 
+   || n>=0x7fffff00
+  ){
     /* A memory allocation of a number of bytes which is near the maximum
     ** signed integer value might cause an integer overflow inside of the
     ** xMalloc().  Hence we limit the maximum size to 0x7fffff00, giving
@@ -16793,6 +17668,7 @@
   }else{
     p = sqlite3GlobalConfig.m.xMalloc(n);
   }
+  assert( EIGHT_BYTE_ALIGNMENT(p) );  /* IMP: R-04675-44850 */
   return p;
 }
 
@@ -16831,81 +17707,42 @@
   void *p;
   assert( n>0 );
 
+  sqlite3_mutex_enter(mem0.mutex);
+  if( mem0.nScratchFree && sqlite3GlobalConfig.szScratch>=n ){
+    p = mem0.pScratchFree;
+    mem0.pScratchFree = mem0.pScratchFree->pNext;
+    mem0.nScratchFree--;
+    sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_USED, 1);
+    sqlite3StatusSet(SQLITE_STATUS_SCRATCH_SIZE, n);
+    sqlite3_mutex_leave(mem0.mutex);
+  }else{
+    if( sqlite3GlobalConfig.bMemstat ){
+      sqlite3StatusSet(SQLITE_STATUS_SCRATCH_SIZE, n);
+      n = mallocWithAlarm(n, &p);
+      if( p ) sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_OVERFLOW, n);
+      sqlite3_mutex_leave(mem0.mutex);
+    }else{
+      sqlite3_mutex_leave(mem0.mutex);
+      p = sqlite3GlobalConfig.m.xMalloc(n);
+    }
+    sqlite3MemdebugSetType(p, MEMTYPE_SCRATCH);
+  }
+  assert( sqlite3_mutex_notheld(mem0.mutex) );
+
+
 #if SQLITE_THREADSAFE==0 && !defined(NDEBUG)
-  /* Verify that no more than two scratch allocation per thread
-  ** is outstanding at one time.  (This is only checked in the
+  /* Verify that no more than two scratch allocations per thread
+  ** are outstanding at one time.  (This is only checked in the
   ** single-threaded case since checking in the multi-threaded case
   ** would be much more complicated.) */
   assert( scratchAllocOut<=1 );
-#endif
-
-  if( sqlite3GlobalConfig.szScratch<n ){
-    goto scratch_overflow;
-  }else{  
-    sqlite3_mutex_enter(mem0.mutex);
-    if( mem0.nScratchFree==0 ){
-      sqlite3_mutex_leave(mem0.mutex);
-      goto scratch_overflow;
-    }else{
-      int i;
-      i = mem0.aScratchFree[--mem0.nScratchFree];
-      i *= sqlite3GlobalConfig.szScratch;
-      sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_USED, 1);
-      sqlite3StatusSet(SQLITE_STATUS_SCRATCH_SIZE, n);
-      sqlite3_mutex_leave(mem0.mutex);
-      p = (void*)&((char*)sqlite3GlobalConfig.pScratch)[i];
-      assert(  (((u8*)p - (u8*)0) & 7)==0 );
-    }
-  }
-#if SQLITE_THREADSAFE==0 && !defined(NDEBUG)
-  scratchAllocOut = p!=0;
+  if( p ) scratchAllocOut++;
 #endif
 
   return p;
-
-scratch_overflow:
-  if( sqlite3GlobalConfig.bMemstat ){
-    sqlite3_mutex_enter(mem0.mutex);
-    sqlite3StatusSet(SQLITE_STATUS_SCRATCH_SIZE, n);
-    n = mallocWithAlarm(n, &p);
-    if( p ) sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_OVERFLOW, n);
-    sqlite3_mutex_leave(mem0.mutex);
-  }else{
-    p = sqlite3GlobalConfig.m.xMalloc(n);
-  }
-  sqlite3MemdebugSetType(p, MEMTYPE_SCRATCH);
-#if SQLITE_THREADSAFE==0 && !defined(NDEBUG)
-  scratchAllocOut = p!=0;
-#endif
-  return p;    
 }
 SQLITE_PRIVATE void sqlite3ScratchFree(void *p){
   if( p ){
-    if( sqlite3GlobalConfig.pScratch==0
-           || p<sqlite3GlobalConfig.pScratch
-           || p>=(void*)mem0.aScratchFree ){
-      assert( sqlite3MemdebugHasType(p, MEMTYPE_SCRATCH) );
-      sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
-      if( sqlite3GlobalConfig.bMemstat ){
-        int iSize = sqlite3MallocSize(p);
-        sqlite3_mutex_enter(mem0.mutex);
-        sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_OVERFLOW, -iSize);
-        sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, -iSize);
-        sqlite3GlobalConfig.m.xFree(p);
-        sqlite3_mutex_leave(mem0.mutex);
-      }else{
-        sqlite3GlobalConfig.m.xFree(p);
-      }
-    }else{
-      int i;
-      i = (int)((u8*)p - (u8*)sqlite3GlobalConfig.pScratch);
-      i /= sqlite3GlobalConfig.szScratch;
-      assert( i>=0 && i<sqlite3GlobalConfig.nScratch );
-      sqlite3_mutex_enter(mem0.mutex);
-      assert( mem0.nScratchFree<(u32)sqlite3GlobalConfig.nScratch );
-      mem0.aScratchFree[mem0.nScratchFree++] = i;
-      sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_USED, -1);
-      sqlite3_mutex_leave(mem0.mutex);
 
 #if SQLITE_THREADSAFE==0 && !defined(NDEBUG)
     /* Verify that no more than two scratch allocation per thread
@@ -16913,9 +17750,36 @@
     ** single-threaded case since checking in the multi-threaded case
     ** would be much more complicated.) */
     assert( scratchAllocOut>=1 && scratchAllocOut<=2 );
-    scratchAllocOut = 0;
+    scratchAllocOut--;
 #endif
 
+    if( p>=sqlite3GlobalConfig.pScratch && p<mem0.pScratchEnd ){
+      /* Release memory from the SQLITE_CONFIG_SCRATCH allocation */
+      ScratchFreeslot *pSlot;
+      pSlot = (ScratchFreeslot*)p;
+      sqlite3_mutex_enter(mem0.mutex);
+      pSlot->pNext = mem0.pScratchFree;
+      mem0.pScratchFree = pSlot;
+      mem0.nScratchFree++;
+      assert( mem0.nScratchFree<=sqlite3GlobalConfig.nScratch );
+      sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_USED, -1);
+      sqlite3_mutex_leave(mem0.mutex);
+    }else{
+      /* Release memory back to the heap */
+      assert( sqlite3MemdebugHasType(p, MEMTYPE_SCRATCH) );
+      assert( sqlite3MemdebugNoType(p, ~MEMTYPE_SCRATCH) );
+      sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
+      if( sqlite3GlobalConfig.bMemstat ){
+        int iSize = sqlite3MallocSize(p);
+        sqlite3_mutex_enter(mem0.mutex);
+        sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_OVERFLOW, -iSize);
+        sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, -iSize);
+        sqlite3StatusAdd(SQLITE_STATUS_MALLOC_COUNT, -1);
+        sqlite3GlobalConfig.m.xFree(p);
+        sqlite3_mutex_leave(mem0.mutex);
+      }else{
+        sqlite3GlobalConfig.m.xFree(p);
+      }
     }
   }
 }
@@ -16925,7 +17789,7 @@
 */
 #ifndef SQLITE_OMIT_LOOKASIDE
 static int isLookaside(sqlite3 *db, void *p){
-  return db && p && p>=db->lookaside.pStart && p<db->lookaside.pEnd;
+  return p && p>=db->lookaside.pStart && p<db->lookaside.pEnd;
 }
 #else
 #define isLookaside(A,B) 0
@@ -16937,15 +17801,17 @@
 */
 SQLITE_PRIVATE int sqlite3MallocSize(void *p){
   assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
+  assert( sqlite3MemdebugNoType(p, MEMTYPE_DB) );
   return sqlite3GlobalConfig.m.xSize(p);
 }
 SQLITE_PRIVATE int sqlite3DbMallocSize(sqlite3 *db, void *p){
   assert( db==0 || sqlite3_mutex_held(db->mutex) );
-  if( isLookaside(db, p) ){
+  if( db && isLookaside(db, p) ){
     return db->lookaside.sz;
   }else{
-    assert( sqlite3MemdebugHasType(p,
-             db ? (MEMTYPE_DB|MEMTYPE_HEAP) : MEMTYPE_HEAP) );
+    assert( sqlite3MemdebugHasType(p, MEMTYPE_DB) );
+    assert( sqlite3MemdebugHasType(p, MEMTYPE_LOOKASIDE|MEMTYPE_HEAP) );
+    assert( db!=0 || sqlite3MemdebugNoType(p, MEMTYPE_LOOKASIDE) );
     return sqlite3GlobalConfig.m.xSize(p);
   }
 }
@@ -16954,11 +17820,13 @@
 ** Free memory previously obtained from sqlite3Malloc().
 */
 SQLITE_API void sqlite3_free(void *p){
-  if( p==0 ) return;
+  if( p==0 ) return;  /* IMP: R-49053-54554 */
+  assert( sqlite3MemdebugNoType(p, MEMTYPE_DB) );
   assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
   if( sqlite3GlobalConfig.bMemstat ){
     sqlite3_mutex_enter(mem0.mutex);
     sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, -sqlite3MallocSize(p));
+    sqlite3StatusAdd(SQLITE_STATUS_MALLOC_COUNT, -1);
     sqlite3GlobalConfig.m.xFree(p);
     sqlite3_mutex_leave(mem0.mutex);
   }else{
@@ -16972,16 +17840,24 @@
 */
 SQLITE_PRIVATE void sqlite3DbFree(sqlite3 *db, void *p){
   assert( db==0 || sqlite3_mutex_held(db->mutex) );
-  if( isLookaside(db, p) ){
-    LookasideSlot *pBuf = (LookasideSlot*)p;
-    pBuf->pNext = db->lookaside.pFree;
-    db->lookaside.pFree = pBuf;
-    db->lookaside.nOut--;
-  }else{
-    assert( sqlite3MemdebugHasType(p, MEMTYPE_DB|MEMTYPE_HEAP) );
-    sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
-    sqlite3_free(p);
+  if( db ){
+    if( db->pnBytesFreed ){
+      *db->pnBytesFreed += sqlite3DbMallocSize(db, p);
+      return;
+    }
+    if( isLookaside(db, p) ){
+      LookasideSlot *pBuf = (LookasideSlot*)p;
+      pBuf->pNext = db->lookaside.pFree;
+      db->lookaside.pFree = pBuf;
+      db->lookaside.nOut--;
+      return;
+    }
   }
+  assert( sqlite3MemdebugHasType(p, MEMTYPE_DB) );
+  assert( sqlite3MemdebugHasType(p, MEMTYPE_LOOKASIDE|MEMTYPE_HEAP) );
+  assert( db!=0 || sqlite3MemdebugNoType(p, MEMTYPE_LOOKASIDE) );
+  sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
+  sqlite3_free(p);
 }
 
 /*
@@ -16991,10 +17867,10 @@
   int nOld, nNew;
   void *pNew;
   if( pOld==0 ){
-    return sqlite3Malloc(nBytes);
+    return sqlite3Malloc(nBytes); /* IMP: R-28354-25769 */
   }
   if( nBytes<=0 ){
-    sqlite3_free(pOld);
+    sqlite3_free(pOld); /* IMP: R-31593-10574 */
     return 0;
   }
   if( nBytes>=0x7fffff00 ){
@@ -17002,6 +17878,9 @@
     return 0;
   }
   nOld = sqlite3MallocSize(pOld);
+  /* IMPLEMENTATION-OF: R-46199-30249 SQLite guarantees that the second
+  ** argument to xRealloc is always a value returned by a prior call to
+  ** xRoundup. */
   nNew = sqlite3GlobalConfig.m.xRoundup(nBytes);
   if( nOld==nNew ){
     pNew = pOld;
@@ -17013,6 +17892,7 @@
       sqlite3MallocAlarm(nNew-nOld);
     }
     assert( sqlite3MemdebugHasType(pOld, MEMTYPE_HEAP) );
+    assert( sqlite3MemdebugNoType(pOld, ~MEMTYPE_HEAP) );
     pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
     if( pNew==0 && mem0.alarmCallback ){
       sqlite3MallocAlarm(nBytes);
@@ -17026,6 +17906,7 @@
   }else{
     pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
   }
+  assert( EIGHT_BYTE_ALIGNMENT(pNew) ); /* IMP: R-04675-44850 */
   return pNew;
 }
 
@@ -17085,6 +17966,7 @@
 SQLITE_PRIVATE void *sqlite3DbMallocRaw(sqlite3 *db, int n){
   void *p;
   assert( db==0 || sqlite3_mutex_held(db->mutex) );
+  assert( db==0 || db->pnBytesFreed==0 );
 #ifndef SQLITE_OMIT_LOOKASIDE
   if( db ){
     LookasideSlot *pBuf;
@@ -17110,8 +17992,8 @@
   if( !p && db ){
     db->mallocFailed = 1;
   }
-  sqlite3MemdebugSetType(p,
-            (db && db->lookaside.bEnabled) ? MEMTYPE_DB : MEMTYPE_HEAP);
+  sqlite3MemdebugSetType(p, MEMTYPE_DB |
+         ((db && db->lookaside.bEnabled) ? MEMTYPE_LOOKASIDE : MEMTYPE_HEAP));
   return p;
 }
 
@@ -17137,14 +18019,16 @@
         sqlite3DbFree(db, p);
       }
     }else{
-      assert( sqlite3MemdebugHasType(p, MEMTYPE_DB|MEMTYPE_HEAP) );
+      assert( sqlite3MemdebugHasType(p, MEMTYPE_DB) );
+      assert( sqlite3MemdebugHasType(p, MEMTYPE_LOOKASIDE|MEMTYPE_HEAP) );
       sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
       pNew = sqlite3_realloc(p, n);
       if( !pNew ){
+        sqlite3MemdebugSetType(p, MEMTYPE_DB|MEMTYPE_HEAP);
         db->mallocFailed = 1;
       }
-      sqlite3MemdebugSetType(pNew,
-            db->lookaside.bEnabled ? MEMTYPE_DB : MEMTYPE_HEAP);
+      sqlite3MemdebugSetType(pNew, MEMTYPE_DB | 
+            (db->lookaside.bEnabled ? MEMTYPE_LOOKASIDE : MEMTYPE_HEAP));
     }
   }
   return pNew;
@@ -18017,7 +18901,11 @@
       }else{
         p->nAlloc = (int)szNew;
       }
-      zNew = sqlite3DbMallocRaw(p->db, p->nAlloc );
+      if( p->useMalloc==1 ){
+        zNew = sqlite3DbMallocRaw(p->db, p->nAlloc );
+      }else{
+        zNew = sqlite3_malloc(p->nAlloc);
+      }
       if( zNew ){
         memcpy(zNew, p->zText, p->nChar);
         sqlite3StrAccumReset(p);
@@ -18042,7 +18930,11 @@
   if( p->zText ){
     p->zText[p->nChar] = 0;
     if( p->useMalloc && p->zText==p->zBase ){
-      p->zText = sqlite3DbMallocRaw(p->db, p->nChar+1 );
+      if( p->useMalloc==1 ){
+        p->zText = sqlite3DbMallocRaw(p->db, p->nChar+1 );
+      }else{
+        p->zText = sqlite3_malloc(p->nChar+1);
+      }
       if( p->zText ){
         memcpy(p->zText, p->zBase, p->nChar+1);
       }else{
@@ -18058,7 +18950,11 @@
 */
 SQLITE_PRIVATE void sqlite3StrAccumReset(StrAccum *p){
   if( p->zText!=p->zBase ){
-    sqlite3DbFree(p->db, p->zText);
+    if( p->useMalloc==1 ){
+      sqlite3DbFree(p->db, p->zText);
+    }else{
+      sqlite3_free(p->zText);
+    }
   }
   p->zText = 0;
 }
@@ -18140,6 +19036,7 @@
   if( sqlite3_initialize() ) return 0;
 #endif
   sqlite3StrAccumInit(&acc, zBase, sizeof(zBase), SQLITE_MAX_LENGTH);
+  acc.useMalloc = 2;
   sqlite3VXPrintf(&acc, 0, zFormat, ap);
   z = sqlite3StrAccumFinish(&acc);
   return z;
@@ -18433,429 +19330,6 @@
 **     0xfe 0xff   big-endian utf-16 follows
 **
 */
-/************** Include vdbeInt.h in the middle of utf.c *********************/
-/************** Begin file vdbeInt.h *****************************************/
-/*
-** 2003 September 6
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-** This is the header file for information that is private to the
-** VDBE.  This information used to all be at the top of the single
-** source code file "vdbe.c".  When that file became too big (over
-** 6000 lines long) it was split up into several smaller files and
-** this header information was factored out.
-*/
-#ifndef _VDBEINT_H_
-#define _VDBEINT_H_
-
-/*
-** SQL is translated into a sequence of instructions to be
-** executed by a virtual machine.  Each instruction is an instance
-** of the following structure.
-*/
-typedef struct VdbeOp Op;
-
-/*
-** Boolean values
-*/
-typedef unsigned char Bool;
-
-/*
-** A cursor is a pointer into a single BTree within a database file.
-** The cursor can seek to a BTree entry with a particular key, or
-** loop over all entries of the Btree.  You can also insert new BTree
-** entries or retrieve the key or data from the entry that the cursor
-** is currently pointing to.
-** 
-** Every cursor that the virtual machine has open is represented by an
-** instance of the following structure.
-**
-** If the VdbeCursor.isTriggerRow flag is set it means that this cursor is
-** really a single row that represents the NEW or OLD pseudo-table of
-** a row trigger.  The data for the row is stored in VdbeCursor.pData and
-** the rowid is in VdbeCursor.iKey.
-*/
-struct VdbeCursor {
-  BtCursor *pCursor;    /* The cursor structure of the backend */
-  int iDb;              /* Index of cursor database in db->aDb[] (or -1) */
-  i64 lastRowid;        /* Last rowid from a Next or NextIdx operation */
-  Bool zeroed;          /* True if zeroed out and ready for reuse */
-  Bool rowidIsValid;    /* True if lastRowid is valid */
-  Bool atFirst;         /* True if pointing to first entry */
-  Bool useRandomRowid;  /* Generate new record numbers semi-randomly */
-  Bool nullRow;         /* True if pointing to a row with no data */
-  Bool deferredMoveto;  /* A call to sqlite3BtreeMoveto() is needed */
-  Bool isTable;         /* True if a table requiring integer keys */
-  Bool isIndex;         /* True if an index containing keys only - no data */
-  i64 movetoTarget;     /* Argument to the deferred sqlite3BtreeMoveto() */
-  Btree *pBt;           /* Separate file holding temporary table */
-  int pseudoTableReg;   /* Register holding pseudotable content. */
-  KeyInfo *pKeyInfo;    /* Info about index keys needed by index cursors */
-  int nField;           /* Number of fields in the header */
-  i64 seqCount;         /* Sequence counter */
-  sqlite3_vtab_cursor *pVtabCursor;  /* The cursor for a virtual table */
-  const sqlite3_module *pModule;     /* Module for cursor pVtabCursor */
-
-  /* Result of last sqlite3BtreeMoveto() done by an OP_NotExists or 
-  ** OP_IsUnique opcode on this cursor. */
-  int seekResult;
-
-  /* Cached information about the header for the data record that the
-  ** cursor is currently pointing to.  Only valid if cacheStatus matches
-  ** Vdbe.cacheCtr.  Vdbe.cacheCtr will never take on the value of
-  ** CACHE_STALE and so setting cacheStatus=CACHE_STALE guarantees that
-  ** the cache is out of date.
-  **
-  ** aRow might point to (ephemeral) data for the current row, or it might
-  ** be NULL.
-  */
-  u32 cacheStatus;      /* Cache is valid if this matches Vdbe.cacheCtr */
-  int payloadSize;      /* Total number of bytes in the record */
-  u32 *aType;           /* Type values for all entries in the record */
-  u32 *aOffset;         /* Cached offsets to the start of each columns data */
-  u8 *aRow;             /* Data for the current row, if all on one page */
-};
-typedef struct VdbeCursor VdbeCursor;
-
-/*
-** When a sub-program is executed (OP_Program), a structure of this type
-** is allocated to store the current value of the program counter, as
-** well as the current memory cell array and various other frame specific
-** values stored in the Vdbe struct. When the sub-program is finished, 
-** these values are copied back to the Vdbe from the VdbeFrame structure,
-** restoring the state of the VM to as it was before the sub-program
-** began executing.
-**
-** Frames are stored in a linked list headed at Vdbe.pParent. Vdbe.pParent
-** is the parent of the current frame, or zero if the current frame
-** is the main Vdbe program.
-*/
-typedef struct VdbeFrame VdbeFrame;
-struct VdbeFrame {
-  Vdbe *v;                /* VM this frame belongs to */
-  int pc;                 /* Program Counter */
-  Op *aOp;                /* Program instructions */
-  int nOp;                /* Size of aOp array */
-  Mem *aMem;              /* Array of memory cells */
-  int nMem;               /* Number of entries in aMem */
-  VdbeCursor **apCsr;     /* Element of Vdbe cursors */
-  u16 nCursor;            /* Number of entries in apCsr */
-  void *token;            /* Copy of SubProgram.token */
-  int nChildMem;          /* Number of memory cells for child frame */
-  int nChildCsr;          /* Number of cursors for child frame */
-  i64 lastRowid;          /* Last insert rowid (sqlite3.lastRowid) */
-  int nChange;            /* Statement changes (Vdbe.nChanges)     */
-  VdbeFrame *pParent;     /* Parent of this frame */
-};
-
-#define VdbeFrameMem(p) ((Mem *)&((u8 *)p)[ROUND8(sizeof(VdbeFrame))])
-
-/*
-** A value for VdbeCursor.cacheValid that means the cache is always invalid.
-*/
-#define CACHE_STALE 0
-
-/*
-** Internally, the vdbe manipulates nearly all SQL values as Mem
-** structures. Each Mem struct may cache multiple representations (string,
-** integer etc.) of the same value.  A value (and therefore Mem structure)
-** has the following properties:
-**
-** Each value has a manifest type. The manifest type of the value stored
-** in a Mem struct is returned by the MemType(Mem*) macro. The type is
-** one of SQLITE_NULL, SQLITE_INTEGER, SQLITE_REAL, SQLITE_TEXT or
-** SQLITE_BLOB.
-*/
-struct Mem {
-  union {
-    i64 i;              /* Integer value. */
-    int nZero;          /* Used when bit MEM_Zero is set in flags */
-    FuncDef *pDef;      /* Used only when flags==MEM_Agg */
-    RowSet *pRowSet;    /* Used only when flags==MEM_RowSet */
-    VdbeFrame *pFrame;  /* Used when flags==MEM_Frame */
-  } u;
-  double r;           /* Real value */
-  sqlite3 *db;        /* The associated database connection */
-  char *z;            /* String or BLOB value */
-  int n;              /* Number of characters in string value, excluding '\0' */
-  u16 flags;          /* Some combination of MEM_Null, MEM_Str, MEM_Dyn, etc. */
-  u8  type;           /* One of SQLITE_NULL, SQLITE_TEXT, SQLITE_INTEGER, etc */
-  u8  enc;            /* SQLITE_UTF8, SQLITE_UTF16BE, SQLITE_UTF16LE */
-  void (*xDel)(void *);  /* If not null, call this function to delete Mem.z */
-  char *zMalloc;      /* Dynamic buffer allocated by sqlite3_malloc() */
-};
-
-/* One or more of the following flags are set to indicate the validOK
-** representations of the value stored in the Mem struct.
-**
-** If the MEM_Null flag is set, then the value is an SQL NULL value.
-** No other flags may be set in this case.
-**
-** If the MEM_Str flag is set then Mem.z points at a string representation.
-** Usually this is encoded in the same unicode encoding as the main
-** database (see below for exceptions). If the MEM_Term flag is also
-** set, then the string is nul terminated. The MEM_Int and MEM_Real 
-** flags may coexist with the MEM_Str flag.
-**
-** Multiple of these values can appear in Mem.flags.  But only one
-** at a time can appear in Mem.type.
-*/
-#define MEM_Null      0x0001   /* Value is NULL */
-#define MEM_Str       0x0002   /* Value is a string */
-#define MEM_Int       0x0004   /* Value is an integer */
-#define MEM_Real      0x0008   /* Value is a real number */
-#define MEM_Blob      0x0010   /* Value is a BLOB */
-#define MEM_RowSet    0x0020   /* Value is a RowSet object */
-#define MEM_Frame     0x0040   /* Value is a VdbeFrame object */
-#define MEM_TypeMask  0x00ff   /* Mask of type bits */
-
-/* Whenever Mem contains a valid string or blob representation, one of
-** the following flags must be set to determine the memory management
-** policy for Mem.z.  The MEM_Term flag tells us whether or not the
-** string is \000 or \u0000 terminated
-*/
-#define MEM_Term      0x0200   /* String rep is nul terminated */
-#define MEM_Dyn       0x0400   /* Need to call sqliteFree() on Mem.z */
-#define MEM_Static    0x0800   /* Mem.z points to a static string */
-#define MEM_Ephem     0x1000   /* Mem.z points to an ephemeral string */
-#define MEM_Agg       0x2000   /* Mem.z points to an agg function context */
-#define MEM_Zero      0x4000   /* Mem.i contains count of 0s appended to blob */
-
-#ifdef SQLITE_OMIT_INCRBLOB
-  #undef MEM_Zero
-  #define MEM_Zero 0x0000
-#endif
-
-
-/*
-** Clear any existing type flags from a Mem and replace them with f
-*/
-#define MemSetTypeFlag(p, f) \
-   ((p)->flags = ((p)->flags&~(MEM_TypeMask|MEM_Zero))|f)
-
-
-/* A VdbeFunc is just a FuncDef (defined in sqliteInt.h) that contains
-** additional information about auxiliary information bound to arguments
-** of the function.  This is used to implement the sqlite3_get_auxdata()
-** and sqlite3_set_auxdata() APIs.  The "auxdata" is some auxiliary data
-** that can be associated with a constant argument to a function.  This
-** allows functions such as "regexp" to compile their constant regular
-** expression argument once and reused the compiled code for multiple
-** invocations.
-*/
-struct VdbeFunc {
-  FuncDef *pFunc;               /* The definition of the function */
-  int nAux;                     /* Number of entries allocated for apAux[] */
-  struct AuxData {
-    void *pAux;                   /* Aux data for the i-th argument */
-    void (*xDelete)(void *);      /* Destructor for the aux data */
-  } apAux[1];                   /* One slot for each function argument */
-};
-
-/*
-** The "context" argument for a installable function.  A pointer to an
-** instance of this structure is the first argument to the routines used
-** implement the SQL functions.
-**
-** There is a typedef for this structure in sqlite.h.  So all routines,
-** even the public interface to SQLite, can use a pointer to this structure.
-** But this file is the only place where the internal details of this
-** structure are known.
-**
-** This structure is defined inside of vdbeInt.h because it uses substructures
-** (Mem) which are only defined there.
-*/
-struct sqlite3_context {
-  FuncDef *pFunc;       /* Pointer to function information.  MUST BE FIRST */
-  VdbeFunc *pVdbeFunc;  /* Auxilary data, if created. */
-  Mem s;                /* The return value is stored here */
-  Mem *pMem;            /* Memory cell used to store aggregate context */
-  int isError;          /* Error code returned by the function. */
-  CollSeq *pColl;       /* Collating sequence */
-};
-
-/*
-** A Set structure is used for quick testing to see if a value
-** is part of a small set.  Sets are used to implement code like
-** this:
-**            x.y IN ('hi','hoo','hum')
-*/
-typedef struct Set Set;
-struct Set {
-  Hash hash;             /* A set is just a hash table */
-  HashElem *prev;        /* Previously accessed hash elemen */
-};
-
-/*
-** An instance of the virtual machine.  This structure contains the complete
-** state of the virtual machine.
-**
-** The "sqlite3_stmt" structure pointer that is returned by sqlite3_compile()
-** is really a pointer to an instance of this structure.
-**
-** The Vdbe.inVtabMethod variable is set to non-zero for the duration of
-** any virtual table method invocations made by the vdbe program. It is
-** set to 2 for xDestroy method calls and 1 for all other methods. This
-** variable is used for two purposes: to allow xDestroy methods to execute
-** "DROP TABLE" statements and to prevent some nasty side effects of
-** malloc failure when SQLite is invoked recursively by a virtual table 
-** method function.
-*/
-struct Vdbe {
-  sqlite3 *db;            /* The database connection that owns this statement */
-  Vdbe *pPrev,*pNext;     /* Linked list of VDBEs with the same Vdbe.db */
-  int nOp;                /* Number of instructions in the program */
-  int nOpAlloc;           /* Number of slots allocated for aOp[] */
-  Op *aOp;                /* Space to hold the virtual machine's program */
-  int nLabel;             /* Number of labels used */
-  int nLabelAlloc;        /* Number of slots allocated in aLabel[] */
-  int *aLabel;            /* Space to hold the labels */
-  Mem **apArg;            /* Arguments to currently executing user function */
-  Mem *aColName;          /* Column names to return */
-  Mem *pResultSet;        /* Pointer to an array of results */
-  u16 nResColumn;         /* Number of columns in one row of the result set */
-  u16 nCursor;            /* Number of slots in apCsr[] */
-  VdbeCursor **apCsr;     /* One element of this array for each open cursor */
-  u8 errorAction;         /* Recovery action to do in case of an error */
-  u8 okVar;               /* True if azVar[] has been initialized */
-  ynVar nVar;             /* Number of entries in aVar[] */
-  Mem *aVar;              /* Values for the OP_Variable opcode. */
-  char **azVar;           /* Name of variables */
-  u32 magic;              /* Magic number for sanity checking */
-  int nMem;               /* Number of memory locations currently allocated */
-  Mem *aMem;              /* The memory locations */
-  u32 cacheCtr;           /* VdbeCursor row cache generation counter */
-  int pc;                 /* The program counter */
-  int rc;                 /* Value to return */
-  char *zErrMsg;          /* Error message written here */
-  u8 explain;             /* True if EXPLAIN present on SQL command */
-  u8 changeCntOn;         /* True to update the change-counter */
-  u8 expired;             /* True if the VM needs to be recompiled */
-  u8 runOnlyOnce;         /* Automatically expire on reset */
-  u8 minWriteFileFormat;  /* Minimum file format for writable database files */
-  u8 inVtabMethod;        /* See comments above */
-  u8 usesStmtJournal;     /* True if uses a statement journal */
-  u8 readOnly;            /* True for read-only statements */
-  u8 isPrepareV2;         /* True if prepared with prepare_v2() */
-  int nChange;            /* Number of db changes made since last reset */
-  int btreeMask;          /* Bitmask of db->aDb[] entries referenced */
-  i64 startTime;          /* Time when query started - used for profiling */
-  BtreeMutexArray aMutex; /* An array of Btree used here and needing locks */
-  int aCounter[3];        /* Counters used by sqlite3_stmt_status() */
-  char *zSql;             /* Text of the SQL statement that generated this */
-  void *pFree;            /* Free this when deleting the vdbe */
-  i64 nFkConstraint;      /* Number of imm. FK constraints this VM */
-  i64 nStmtDefCons;       /* Number of def. constraints when stmt started */
-  int iStatement;         /* Statement number (or 0 if has not opened stmt) */
-#ifdef SQLITE_DEBUG
-  FILE *trace;            /* Write an execution trace here, if not NULL */
-#endif
-  VdbeFrame *pFrame;      /* Parent frame */
-  int nFrame;             /* Number of frames in pFrame list */
-  u32 expmask;            /* Binding to these vars invalidates VM */
-};
-
-/*
-** The following are allowed values for Vdbe.magic
-*/
-#define VDBE_MAGIC_INIT     0x26bceaa5    /* Building a VDBE program */
-#define VDBE_MAGIC_RUN      0xbdf20da3    /* VDBE is ready to execute */
-#define VDBE_MAGIC_HALT     0x519c2973    /* VDBE has completed execution */
-#define VDBE_MAGIC_DEAD     0xb606c3c8    /* The VDBE has been deallocated */
-
-/*
-** Function prototypes
-*/
-SQLITE_PRIVATE void sqlite3VdbeFreeCursor(Vdbe *, VdbeCursor*);
-void sqliteVdbePopStack(Vdbe*,int);
-SQLITE_PRIVATE int sqlite3VdbeCursorMoveto(VdbeCursor*);
-#if defined(SQLITE_DEBUG) || defined(VDBE_PROFILE)
-SQLITE_PRIVATE void sqlite3VdbePrintOp(FILE*, int, Op*);
-#endif
-SQLITE_PRIVATE u32 sqlite3VdbeSerialTypeLen(u32);
-SQLITE_PRIVATE u32 sqlite3VdbeSerialType(Mem*, int);
-SQLITE_PRIVATE u32 sqlite3VdbeSerialPut(unsigned char*, int, Mem*, int);
-SQLITE_PRIVATE u32 sqlite3VdbeSerialGet(const unsigned char*, u32, Mem*);
-SQLITE_PRIVATE void sqlite3VdbeDeleteAuxData(VdbeFunc*, int);
-
-int sqlite2BtreeKeyCompare(BtCursor *, const void *, int, int, int *);
-SQLITE_PRIVATE int sqlite3VdbeIdxKeyCompare(VdbeCursor*,UnpackedRecord*,int*);
-SQLITE_PRIVATE int sqlite3VdbeIdxRowid(sqlite3*, BtCursor *, i64 *);
-SQLITE_PRIVATE int sqlite3MemCompare(const Mem*, const Mem*, const CollSeq*);
-SQLITE_PRIVATE int sqlite3VdbeExec(Vdbe*);
-SQLITE_PRIVATE int sqlite3VdbeList(Vdbe*);
-SQLITE_PRIVATE int sqlite3VdbeHalt(Vdbe*);
-SQLITE_PRIVATE int sqlite3VdbeChangeEncoding(Mem *, int);
-SQLITE_PRIVATE int sqlite3VdbeMemTooBig(Mem*);
-SQLITE_PRIVATE int sqlite3VdbeMemCopy(Mem*, const Mem*);
-SQLITE_PRIVATE void sqlite3VdbeMemShallowCopy(Mem*, const Mem*, int);
-SQLITE_PRIVATE void sqlite3VdbeMemMove(Mem*, Mem*);
-SQLITE_PRIVATE int sqlite3VdbeMemNulTerminate(Mem*);
-SQLITE_PRIVATE int sqlite3VdbeMemSetStr(Mem*, const char*, int, u8, void(*)(void*));
-SQLITE_PRIVATE void sqlite3VdbeMemSetInt64(Mem*, i64);
-#ifdef SQLITE_OMIT_FLOATING_POINT
-# define sqlite3VdbeMemSetDouble sqlite3VdbeMemSetInt64
-#else
-SQLITE_PRIVATE   void sqlite3VdbeMemSetDouble(Mem*, double);
-#endif
-SQLITE_PRIVATE void sqlite3VdbeMemSetNull(Mem*);
-SQLITE_PRIVATE void sqlite3VdbeMemSetZeroBlob(Mem*,int);
-SQLITE_PRIVATE void sqlite3VdbeMemSetRowSet(Mem*);
-SQLITE_PRIVATE int sqlite3VdbeMemMakeWriteable(Mem*);
-SQLITE_PRIVATE int sqlite3VdbeMemStringify(Mem*, int);
-SQLITE_PRIVATE i64 sqlite3VdbeIntValue(Mem*);
-SQLITE_PRIVATE int sqlite3VdbeMemIntegerify(Mem*);
-SQLITE_PRIVATE double sqlite3VdbeRealValue(Mem*);
-SQLITE_PRIVATE void sqlite3VdbeIntegerAffinity(Mem*);
-SQLITE_PRIVATE int sqlite3VdbeMemRealify(Mem*);
-SQLITE_PRIVATE int sqlite3VdbeMemNumerify(Mem*);
-SQLITE_PRIVATE int sqlite3VdbeMemFromBtree(BtCursor*,int,int,int,Mem*);
-SQLITE_PRIVATE void sqlite3VdbeMemRelease(Mem *p);
-SQLITE_PRIVATE void sqlite3VdbeMemReleaseExternal(Mem *p);
-SQLITE_PRIVATE int sqlite3VdbeMemFinalize(Mem*, FuncDef*);
-SQLITE_PRIVATE const char *sqlite3OpcodeName(int);
-SQLITE_PRIVATE int sqlite3VdbeMemGrow(Mem *pMem, int n, int preserve);
-SQLITE_PRIVATE int sqlite3VdbeCloseStatement(Vdbe *, int);
-SQLITE_PRIVATE void sqlite3VdbeFrameDelete(VdbeFrame*);
-SQLITE_PRIVATE int sqlite3VdbeFrameRestore(VdbeFrame *);
-SQLITE_PRIVATE void sqlite3VdbeMemStoreType(Mem *pMem);
-
-#ifndef SQLITE_OMIT_FOREIGN_KEY
-SQLITE_PRIVATE int sqlite3VdbeCheckFk(Vdbe *, int);
-#else
-# define sqlite3VdbeCheckFk(p,i) 0
-#endif
-
-#ifndef SQLITE_OMIT_SHARED_CACHE
-SQLITE_PRIVATE void sqlite3VdbeMutexArrayEnter(Vdbe *p);
-#else
-# define sqlite3VdbeMutexArrayEnter(p)
-#endif
-
-SQLITE_PRIVATE int sqlite3VdbeMemTranslate(Mem*, u8);
-#ifdef SQLITE_DEBUG
-SQLITE_PRIVATE   void sqlite3VdbePrintSql(Vdbe*);
-SQLITE_PRIVATE   void sqlite3VdbeMemPrettyPrint(Mem *pMem, char *zBuf);
-#endif
-SQLITE_PRIVATE int sqlite3VdbeMemHandleBom(Mem *pMem);
-
-#ifndef SQLITE_OMIT_INCRBLOB
-SQLITE_PRIVATE   int sqlite3VdbeMemExpandBlob(Mem *);
-#else
-  #define sqlite3VdbeMemExpandBlob(x) SQLITE_OK
-#endif
-
-#endif /* !defined(_VDBEINT_H_) */
-
-/************** End of vdbeInt.h *********************************************/
-/************** Continuing where we left off in utf.c ************************/
 
 #ifndef SQLITE_AMALGAMATION
 /*
@@ -19596,6 +20070,12 @@
 /*
 ** Some systems have stricmp().  Others have strcasecmp().  Because
 ** there is no consistency, we will define our own.
+**
+** IMPLEMENTATION-OF: R-20522-24639 The sqlite3_strnicmp() API allows
+** applications and extensions to compare the contents of two buffers
+** containing UTF-8 strings in a case-independent fashion, using the same
+** definition of case independence that SQLite uses internally when
+** comparing identifiers.
 */
 SQLITE_PRIVATE int sqlite3StrICmp(const char *zLeft, const char *zRight){
   register unsigned char *a, *b;
@@ -21886,7 +22366,7 @@
 
   memset( pFile, 0, sizeof(*pFile) );
 
-  OSTRACE( "OPEN want %d\n", flags ));
+  OSTRACE(( "OPEN want %d\n", flags ));
 
   if( flags & SQLITE_OPEN_READWRITE ){
     ulOpenMode |= OPEN_ACCESS_READWRITE;
@@ -22446,6 +22926,7 @@
   int fileFlags;                      /* Miscellanous flags */
   const char *zPath;                  /* Name of the file */
   unixShm *pShm;                      /* Shared memory segment information */
+  int szChunk;                        /* Configured by FCNTL_CHUNK_SIZE */
 #if SQLITE_ENABLE_LOCKING_STYLE
   int openFlags;                      /* The flags specified at open() */
 #endif
@@ -25204,6 +25685,7 @@
   }
   SimulateIOError(( wrote=(-1), amt=1 ));
   SimulateDiskfullError(( wrote=0, amt=1 ));
+
   if( amt>0 ){
     if( wrote<0 ){
       /* lastErrno set by seekAndWrite */
@@ -25213,6 +25695,7 @@
       return SQLITE_FULL;
     }
   }
+
   return SQLITE_OK;
 }
 
@@ -25414,12 +25897,23 @@
 ** Truncate an open file to a specified size
 */
 static int unixTruncate(sqlite3_file *id, i64 nByte){
+  unixFile *pFile = (unixFile *)id;
   int rc;
-  assert( id );
+  assert( pFile );
   SimulateIOError( return SQLITE_IOERR_TRUNCATE );
-  rc = ftruncate(((unixFile*)id)->h, (off_t)nByte);
+
+  /* If the user has configured a chunk-size for this file, truncate the
+  ** file so that it consists of an integer number of chunks (i.e. the
+  ** actual file size after the operation may be larger than the requested
+  ** size).
+  */
+  if( pFile->szChunk ){
+    nByte = ((nByte + pFile->szChunk - 1)/pFile->szChunk) * pFile->szChunk;
+  }
+
+  rc = ftruncate(pFile->h, (off_t)nByte);
   if( rc ){
-    ((unixFile*)id)->lastErrno = errno;
+    pFile->lastErrno = errno;
     return SQLITE_IOERR_TRUNCATE;
   }else{
 #ifndef NDEBUG
@@ -25430,8 +25924,8 @@
     ** when restoring a database using the backup API from a zero-length
     ** source.
     */
-    if( ((unixFile*)id)->inNormalWrite && nByte==0 ){
-      ((unixFile*)id)->transCntrChng = 1;
+    if( pFile->inNormalWrite && nByte==0 ){
+      pFile->transCntrChng = 1;
     }
 #endif
 
@@ -25474,6 +25968,54 @@
 static int proxyFileControl(sqlite3_file*,int,void*);
 #endif
 
+/* 
+** This function is called to handle the SQLITE_FCNTL_SIZE_HINT 
+** file-control operation.
+**
+** If the user has configured a chunk-size for this file, it could be
+** that the file needs to be extended at this point. Otherwise, the
+** SQLITE_FCNTL_SIZE_HINT operation is a no-op for Unix.
+*/
+static int fcntlSizeHint(unixFile *pFile, i64 nByte){
+  if( pFile->szChunk ){
+    i64 nSize;                    /* Required file size */
+    struct stat buf;              /* Used to hold return values of fstat() */
+   
+    if( fstat(pFile->h, &buf) ) return SQLITE_IOERR_FSTAT;
+
+    nSize = ((nByte+pFile->szChunk-1) / pFile->szChunk) * pFile->szChunk;
+    if( nSize>(i64)buf.st_size ){
+#if defined(HAVE_POSIX_FALLOCATE) && HAVE_POSIX_FALLOCATE
+      if( posix_fallocate(pFile->h, buf.st_size, nSize-buf.st_size) ){
+        return SQLITE_IOERR_WRITE;
+      }
+#else
+      /* If the OS does not have posix_fallocate(), fake it. First use
+      ** ftruncate() to set the file size, then write a single byte to
+      ** the last byte in each block within the extended region. This
+      ** is the same technique used by glibc to implement posix_fallocate()
+      ** on systems that do not have a real fallocate() system call.
+      */
+      int nBlk = buf.st_blksize;  /* File-system block size */
+      i64 iWrite;                 /* Next offset to write to */
+      int nWrite;                 /* Return value from seekAndWrite() */
+
+      if( ftruncate(pFile->h, nSize) ){
+        pFile->lastErrno = errno;
+        return SQLITE_IOERR_TRUNCATE;
+      }
+      iWrite = ((buf.st_size + 2*nBlk - 1)/nBlk)*nBlk-1;
+      do {
+        nWrite = seekAndWrite(pFile, iWrite, "", 1);
+        iWrite += nBlk;
+      } while( nWrite==1 && iWrite<nSize );
+      if( nWrite!=1 ) return SQLITE_IOERR_WRITE;
+#endif
+    }
+  }
+
+  return SQLITE_OK;
+}
 
 /*
 ** Information and control of an open file handle.
@@ -25488,14 +26030,13 @@
       *(int*)pArg = ((unixFile*)id)->lastErrno;
       return SQLITE_OK;
     }
-    case SQLITE_FCNTL_SIZE_HINT: {
-#if 0 /* No performance advantage seen on Linux */
-      sqlite3_int64 szFile = *(sqlite3_int64*)pArg;
-      unixFile *pFile = (unixFile*)id;
-      ftruncate(pFile->h, szFile);
-#endif
+    case SQLITE_FCNTL_CHUNK_SIZE: {
+      ((unixFile*)id)->szChunk = *(int *)pArg;
       return SQLITE_OK;
     }
+    case SQLITE_FCNTL_SIZE_HINT: {
+      return fcntlSizeHint((unixFile *)id, *(i64 *)pArg);
+    }
 #ifndef NDEBUG
     /* The pager calls this method to signal that it has done
     ** a rollback and that the database is therefore unchanged and
@@ -25716,52 +26257,72 @@
 }
 
 /*
-** Open a shared-memory area associated with open database file fd.  
+** Open a shared-memory area associated with open database file pDbFd.  
 ** This particular implementation uses mmapped files.
 **
 ** The file used to implement shared-memory is in the same directory
 ** as the open database file and has the same name as the open database
 ** file with the "-shm" suffix added.  For example, if the database file
 ** is "/home/user1/config.db" then the file that is created and mmapped
-** for shared memory will be called "/home/user1/config.db-shm".  We
-** experimented with using files in /dev/tmp or an some other tmpfs mount.
-** But if a file in a different directory from the database file is used,
-** then differing access permissions or a chroot() might cause two different 
-** processes on the same database to end up using different files for 
-** shared memory - meaning that their memory would not really be shared - 
-** resulting in database corruption.
+** for shared memory will be called "/home/user1/config.db-shm".  
+**
+** Another approach to is to use files in /dev/shm or /dev/tmp or an
+** some other tmpfs mount. But if a file in a different directory
+** from the database file is used, then differing access permissions
+** or a chroot() might cause two different processes on the same
+** database to end up using different files for shared memory - 
+** meaning that their memory would not really be shared - resulting
+** in database corruption.  Nevertheless, this tmpfs file usage
+** can be enabled at compile-time using -DSQLITE_SHM_DIRECTORY="/dev/shm"
+** or the equivalent.  The use of the SQLITE_SHM_DIRECTORY compile-time
+** option results in an incompatible build of SQLite;  builds of SQLite
+** that with differing SQLITE_SHM_DIRECTORY settings attempt to use the
+** same database file at the same time, database corruption will likely
+** result. The SQLITE_SHM_DIRECTORY compile-time option is considered
+** "unsupported" and may go away in a future SQLite release.
 **
 ** When opening a new shared-memory file, if no other instances of that
 ** file are currently open, in this process or in other processes, then
 ** the file must be truncated to zero length or have its header cleared.
 */
-static int unixShmOpen(
-  sqlite3_file *fd      /* The file descriptor of the associated database */
-){
-  struct unixShm *p = 0;             /* The connection to be opened */
-  struct unixShmNode *pShmNode = 0;  /* The underlying mmapped file */
-  int rc;                            /* Result code */
-  struct unixFile *pDbFd;            /* Underlying database file */
-  unixInodeInfo *pInode;             /* The inode of fd */
-  char *zShmFilename;                /* Name of the file used for SHM */
-  int nShmFilename;                  /* Size of the SHM filename in bytes */
+static int unixOpenSharedMemory(unixFile *pDbFd){
+  struct unixShm *p = 0;          /* The connection to be opened */
+  struct unixShmNode *pShmNode;   /* The underlying mmapped file */
+  int rc;                         /* Result code */
+  unixInodeInfo *pInode;          /* The inode of fd */
+  char *zShmFilename;             /* Name of the file used for SHM */
+  int nShmFilename;               /* Size of the SHM filename in bytes */
 
-  /* Allocate space for the new sqlite3_shm object.
-  */
+  /* Allocate space for the new unixShm object. */
   p = sqlite3_malloc( sizeof(*p) );
   if( p==0 ) return SQLITE_NOMEM;
   memset(p, 0, sizeof(*p));
-  pDbFd = (struct unixFile*)fd;
   assert( pDbFd->pShm==0 );
 
-  /* Check to see if a unixShmNode object already exists.  Reuse an existing
-  ** one if present.  Create a new one if necessary.
+  /* Check to see if a unixShmNode object already exists. Reuse an existing
+  ** one if present. Create a new one if necessary.
   */
   unixEnterMutex();
   pInode = pDbFd->pInode;
   pShmNode = pInode->pShmNode;
   if( pShmNode==0 ){
+    struct stat sStat;                 /* fstat() info for database file */
+
+    /* Call fstat() to figure out the permissions on the database file. If
+    ** a new *-shm file is created, an attempt will be made to create it
+    ** with the same permissions. The actual permissions the file is created
+    ** with are subject to the current umask setting.
+    */
+    if( fstat(pDbFd->h, &sStat) ){
+      rc = SQLITE_IOERR_FSTAT;
+      goto shm_open_err;
+    }
+
+#ifdef SQLITE_SHM_DIRECTORY
+    nShmFilename = sizeof(SQLITE_SHM_DIRECTORY) + 30;
+#else
     nShmFilename = 5 + (int)strlen(pDbFd->zPath);
+#endif
     pShmNode = sqlite3_malloc( sizeof(*pShmNode) + nShmFilename );
     if( pShmNode==0 ){
       rc = SQLITE_NOMEM;
@@ -25769,7 +26330,13 @@
     }
     memset(pShmNode, 0, sizeof(*pShmNode));
     zShmFilename = pShmNode->zFilename = (char*)&pShmNode[1];
+#ifdef SQLITE_SHM_DIRECTORY
+    sqlite3_snprintf(nShmFilename, zShmFilename, 
+                     SQLITE_SHM_DIRECTORY "/sqlite-shm-%x-%x",
+                     (u32)sStat.st_ino, (u32)sStat.st_dev);
+#else
     sqlite3_snprintf(nShmFilename, zShmFilename, "%s-shm", pDbFd->zPath);
+#endif
     pShmNode->h = -1;
     pDbFd->pInode->pShmNode = pShmNode;
     pShmNode->pInode = pDbFd->pInode;
@@ -25779,7 +26346,7 @@
       goto shm_open_err;
     }
 
-    pShmNode->h = open(zShmFilename, O_RDWR|O_CREAT, 0664);
+    pShmNode->h = open(zShmFilename, O_RDWR|O_CREAT, (sStat.st_mode & 0777));
     if( pShmNode->h<0 ){
       rc = SQLITE_CANTOPEN_BKPT;
       goto shm_open_err;
@@ -25802,14 +26369,24 @@
 
   /* Make the new connection a child of the unixShmNode */
   p->pShmNode = pShmNode;
-  p->pNext = pShmNode->pFirst;
 #ifdef SQLITE_DEBUG
   p->id = pShmNode->nextShmId++;
 #endif
-  pShmNode->pFirst = p;
   pShmNode->nRef++;
   pDbFd->pShm = p;
   unixLeaveMutex();
+
+  /* The reference count on pShmNode has already been incremented under
+  ** the cover of the unixEnterMutex() mutex and the pointer from the
+  ** new (struct unixShm) object to the pShmNode has been set. All that is
+  ** left to do is to link the new object into the linked list starting
+  ** at pShmNode->pFirst. This must be done while holding the pShmNode->mutex 
+  ** mutex.
+  */
+  sqlite3_mutex_enter(pShmNode->mutex);
+  p->pNext = pShmNode->pFirst;
+  pShmNode->pFirst = p;
+  sqlite3_mutex_leave(pShmNode->mutex);
   return SQLITE_OK;
 
   /* Jump here on any error */
@@ -25821,49 +26398,107 @@
 }
 
 /*
-** Close a connection to shared-memory.  Delete the underlying 
-** storage if deleteFlag is true.
+** This function is called to obtain a pointer to region iRegion of the 
+** shared-memory associated with the database file fd. Shared-memory regions 
+** are numbered starting from zero. Each shared-memory region is szRegion 
+** bytes in size.
+**
+** If an error occurs, an error code is returned and *pp is set to NULL.
+**
+** Otherwise, if the bExtend parameter is 0 and the requested shared-memory
+** region has not been allocated (by any client, including one running in a
+** separate process), then *pp is set to NULL and SQLITE_OK returned. If 
+** bExtend is non-zero and the requested shared-memory region has not yet 
+** been allocated, it is allocated by this function.
+**
+** If the shared-memory region has already been allocated or is allocated by
+** this call as described above, then it is mapped into this processes 
+** address space (if it is not already), *pp is set to point to the mapped 
+** memory and SQLITE_OK returned.
 */
-static int unixShmClose(
-  sqlite3_file *fd,          /* The underlying database file */
-  int deleteFlag             /* Delete shared-memory if true */
+static int unixShmMap(
+  sqlite3_file *fd,               /* Handle open on database file */
+  int iRegion,                    /* Region to retrieve */
+  int szRegion,                   /* Size of regions */
+  int bExtend,                    /* True to extend file if necessary */
+  void volatile **pp              /* OUT: Mapped memory */
 ){
-  unixShm *p;            /* The connection to be closed */
-  unixShmNode *pShmNode; /* The underlying shared-memory file */
-  unixShm **pp;          /* For looping over sibling connections */
-  unixFile *pDbFd;       /* The underlying database file */
+  unixFile *pDbFd = (unixFile*)fd;
+  unixShm *p;
+  unixShmNode *pShmNode;
+  int rc = SQLITE_OK;
 
-  pDbFd = (unixFile*)fd;
-  p = pDbFd->pShm;
-  if( p==0 ) return SQLITE_OK;
-  pShmNode = p->pShmNode;
-
-  assert( pShmNode==pDbFd->pInode->pShmNode );
-  assert( pShmNode->pInode==pDbFd->pInode );
-
-  /* Remove connection p from the set of connections associated
-  ** with pShmNode */
-  sqlite3_mutex_enter(pShmNode->mutex);
-  for(pp=&pShmNode->pFirst; (*pp)!=p; pp = &(*pp)->pNext){}
-  *pp = p->pNext;
-
-  /* Free the connection p */
-  sqlite3_free(p);
-  pDbFd->pShm = 0;
-  sqlite3_mutex_leave(pShmNode->mutex);
-
-  /* If pShmNode->nRef has reached 0, then close the underlying
-  ** shared-memory file, too */
-  unixEnterMutex();
-  assert( pShmNode->nRef>0 );
-  pShmNode->nRef--;
-  if( pShmNode->nRef==0 ){
-    if( deleteFlag ) unlink(pShmNode->zFilename);
-    unixShmPurge(pDbFd);
+  /* If the shared-memory file has not yet been opened, open it now. */
+  if( pDbFd->pShm==0 ){
+    rc = unixOpenSharedMemory(pDbFd);
+    if( rc!=SQLITE_OK ) return rc;
   }
-  unixLeaveMutex();
 
-  return SQLITE_OK;
+  p = pDbFd->pShm;
+  pShmNode = p->pShmNode;
+  sqlite3_mutex_enter(pShmNode->mutex);
+  assert( szRegion==pShmNode->szRegion || pShmNode->nRegion==0 );
+
+  if( pShmNode->nRegion<=iRegion ){
+    char **apNew;                      /* New apRegion[] array */
+    int nByte = (iRegion+1)*szRegion;  /* Minimum required file size */
+    struct stat sStat;                 /* Used by fstat() */
+
+    pShmNode->szRegion = szRegion;
+
+    /* The requested region is not mapped into this processes address space.
+    ** Check to see if it has been allocated (i.e. if the wal-index file is
+    ** large enough to contain the requested region).
+    */
+    if( fstat(pShmNode->h, &sStat) ){
+      rc = SQLITE_IOERR_SHMSIZE;
+      goto shmpage_out;
+    }
+
+    if( sStat.st_size<nByte ){
+      /* The requested memory region does not exist. If bExtend is set to
+      ** false, exit early. *pp will be set to NULL and SQLITE_OK returned.
+      **
+      ** Alternatively, if bExtend is true, use ftruncate() to allocate
+      ** the requested memory region.
+      */
+      if( !bExtend ) goto shmpage_out;
+      if( ftruncate(pShmNode->h, nByte) ){
+        rc = SQLITE_IOERR_SHMSIZE;
+        goto shmpage_out;
+      }
+    }
+
+    /* Map the requested memory region into this processes address space. */
+    apNew = (char **)sqlite3_realloc(
+        pShmNode->apRegion, (iRegion+1)*sizeof(char *)
+    );
+    if( !apNew ){
+      rc = SQLITE_IOERR_NOMEM;
+      goto shmpage_out;
+    }
+    pShmNode->apRegion = apNew;
+    while(pShmNode->nRegion<=iRegion){
+      void *pMem = mmap(0, szRegion, PROT_READ|PROT_WRITE, 
+          MAP_SHARED, pShmNode->h, pShmNode->nRegion*szRegion
+      );
+      if( pMem==MAP_FAILED ){
+        rc = SQLITE_IOERR;
+        goto shmpage_out;
+      }
+      pShmNode->apRegion[pShmNode->nRegion] = pMem;
+      pShmNode->nRegion++;
+    }
+  }
+
+shmpage_out:
+  if( pShmNode->nRegion>iRegion ){
+    *pp = pShmNode->apRegion[iRegion];
+  }else{
+    *pp = 0;
+  }
+  sqlite3_mutex_leave(pShmNode->mutex);
+  return rc;
 }
 
 /*
@@ -25993,107 +26628,60 @@
 }
 
 /*
-** This function is called to obtain a pointer to region iRegion of the 
-** shared-memory associated with the database file fd. Shared-memory regions 
-** are numbered starting from zero. Each shared-memory region is szRegion 
-** bytes in size.
+** Close a connection to shared-memory.  Delete the underlying 
+** storage if deleteFlag is true.
 **
-** If an error occurs, an error code is returned and *pp is set to NULL.
-**
-** Otherwise, if the isWrite parameter is 0 and the requested shared-memory
-** region has not been allocated (by any client, including one running in a
-** separate process), then *pp is set to NULL and SQLITE_OK returned. If 
-** isWrite is non-zero and the requested shared-memory region has not yet 
-** been allocated, it is allocated by this function.
-**
-** If the shared-memory region has already been allocated or is allocated by
-** this call as described above, then it is mapped into this processes 
-** address space (if it is not already), *pp is set to point to the mapped 
-** memory and SQLITE_OK returned.
+** If there is no shared memory associated with the connection then this
+** routine is a harmless no-op.
 */
-static int unixShmMap(
-  sqlite3_file *fd,               /* Handle open on database file */
-  int iRegion,                    /* Region to retrieve */
-  int szRegion,                   /* Size of regions */
-  int isWrite,                    /* True to extend file if necessary */
-  void volatile **pp              /* OUT: Mapped memory */
+static int unixShmUnmap(
+  sqlite3_file *fd,               /* The underlying database file */
+  int deleteFlag                  /* Delete shared-memory if true */
 ){
-  unixFile *pDbFd = (unixFile*)fd;
-  unixShm *p = pDbFd->pShm;
-  unixShmNode *pShmNode = p->pShmNode;
-  int rc = SQLITE_OK;
+  unixShm *p;                     /* The connection to be closed */
+  unixShmNode *pShmNode;          /* The underlying shared-memory file */
+  unixShm **pp;                   /* For looping over sibling connections */
+  unixFile *pDbFd;                /* The underlying database file */
 
+  pDbFd = (unixFile*)fd;
+  p = pDbFd->pShm;
+  if( p==0 ) return SQLITE_OK;
+  pShmNode = p->pShmNode;
+
+  assert( pShmNode==pDbFd->pInode->pShmNode );
+  assert( pShmNode->pInode==pDbFd->pInode );
+
+  /* Remove connection p from the set of connections associated
+  ** with pShmNode */
   sqlite3_mutex_enter(pShmNode->mutex);
-  assert( szRegion==pShmNode->szRegion || pShmNode->nRegion==0 );
+  for(pp=&pShmNode->pFirst; (*pp)!=p; pp = &(*pp)->pNext){}
+  *pp = p->pNext;
 
-  if( pShmNode->nRegion<=iRegion ){
-    char **apNew;                      /* New apRegion[] array */
-    int nByte = (iRegion+1)*szRegion;  /* Minimum required file size */
-    struct stat sStat;                 /* Used by fstat() */
-
-    pShmNode->szRegion = szRegion;
-
-    /* The requested region is not mapped into this processes address space.
-    ** Check to see if it has been allocated (i.e. if the wal-index file is
-    ** large enough to contain the requested region).
-    */
-    if( fstat(pShmNode->h, &sStat) ){
-      rc = SQLITE_IOERR_SHMSIZE;
-      goto shmpage_out;
-    }
-
-    if( sStat.st_size<nByte ){
-      /* The requested memory region does not exist. If isWrite is set to
-      ** zero, exit early. *pp will be set to NULL and SQLITE_OK returned.
-      **
-      ** Alternatively, if isWrite is non-zero, use ftruncate() to allocate
-      ** the requested memory region.
-      */
-      if( !isWrite ) goto shmpage_out;
-      if( ftruncate(pShmNode->h, nByte) ){
-        rc = SQLITE_IOERR_SHMSIZE;
-        goto shmpage_out;
-      }  
-    }
-
-    /* Map the requested memory region into this processes address space. */
-    apNew = (char **)sqlite3_realloc(
-        pShmNode->apRegion, (iRegion+1)*sizeof(char *)
-    );
-    if( !apNew ){
-      rc = SQLITE_IOERR_NOMEM;
-      goto shmpage_out;
-    }
-    pShmNode->apRegion = apNew;
-    while(pShmNode->nRegion<=iRegion){
-      void *pMem = mmap(0, szRegion, PROT_READ|PROT_WRITE, 
-          MAP_SHARED, pShmNode->h, iRegion*szRegion
-      );
-      if( pMem==MAP_FAILED ){
-        rc = SQLITE_IOERR;
-        goto shmpage_out;
-      }
-      pShmNode->apRegion[pShmNode->nRegion] = pMem;
-      pShmNode->nRegion++;
-    }
-  }
-
-shmpage_out:
-  if( pShmNode->nRegion>iRegion ){
-    *pp = pShmNode->apRegion[iRegion];
-  }else{
-    *pp = 0;
-  }
+  /* Free the connection p */
+  sqlite3_free(p);
+  pDbFd->pShm = 0;
   sqlite3_mutex_leave(pShmNode->mutex);
-  return rc;
+
+  /* If pShmNode->nRef has reached 0, then close the underlying
+  ** shared-memory file, too */
+  unixEnterMutex();
+  assert( pShmNode->nRef>0 );
+  pShmNode->nRef--;
+  if( pShmNode->nRef==0 ){
+    if( deleteFlag ) unlink(pShmNode->zFilename);
+    unixShmPurge(pDbFd);
+  }
+  unixLeaveMutex();
+
+  return SQLITE_OK;
 }
 
+
 #else
-# define unixShmOpen    0
-# define unixShmLock    0
 # define unixShmMap     0
+# define unixShmLock    0
 # define unixShmBarrier 0
-# define unixShmClose   0
+# define unixShmUnmap   0
 #endif /* #ifndef SQLITE_OMIT_WAL */
 
 /*
@@ -26151,11 +26739,10 @@
    unixFileControl,            /* xFileControl */                            \
    unixSectorSize,             /* xSectorSize */                             \
    unixDeviceCharacteristics,  /* xDeviceCapabilities */                     \
-   unixShmOpen,                /* xShmOpen */                                \
-   unixShmLock,                /* xShmLock */                                \
    unixShmMap,                 /* xShmMap */                                 \
+   unixShmLock,                /* xShmLock */                                \
    unixShmBarrier,             /* xShmBarrier */                             \
-   unixShmClose                /* xShmClose */                               \
+   unixShmUnmap                /* xShmUnmap */                               \
 };                                                                           \
 static const sqlite3_io_methods *FINDER##Impl(const char *z, unixFile *p){   \
   UNUSED_PARAMETER(z); UNUSED_PARAMETER(p);                                  \
@@ -26172,7 +26759,7 @@
 IOMETHODS(
   posixIoFinder,            /* Finder function name */
   posixIoMethods,           /* sqlite3_io_methods object name */
-  2,                        /* ShmOpen is enabled */
+  2,                        /* shared memory is enabled */
   unixClose,                /* xClose method */
   unixLock,                 /* xLock method */
   unixUnlock,               /* xUnlock method */
@@ -26181,7 +26768,7 @@
 IOMETHODS(
   nolockIoFinder,           /* Finder function name */
   nolockIoMethods,          /* sqlite3_io_methods object name */
-  1,                        /* ShmOpen is disabled */
+  1,                        /* shared memory is disabled */
   nolockClose,              /* xClose method */
   nolockLock,               /* xLock method */
   nolockUnlock,             /* xUnlock method */
@@ -26190,7 +26777,7 @@
 IOMETHODS(
   dotlockIoFinder,          /* Finder function name */
   dotlockIoMethods,         /* sqlite3_io_methods object name */
-  1,                        /* ShmOpen is disabled */
+  1,                        /* shared memory is disabled */
   dotlockClose,             /* xClose method */
   dotlockLock,              /* xLock method */
   dotlockUnlock,            /* xUnlock method */
@@ -26201,7 +26788,7 @@
 IOMETHODS(
   flockIoFinder,            /* Finder function name */
   flockIoMethods,           /* sqlite3_io_methods object name */
-  1,                        /* ShmOpen is disabled */
+  1,                        /* shared memory is disabled */
   flockClose,               /* xClose method */
   flockLock,                /* xLock method */
   flockUnlock,              /* xUnlock method */
@@ -26213,7 +26800,7 @@
 IOMETHODS(
   semIoFinder,              /* Finder function name */
   semIoMethods,             /* sqlite3_io_methods object name */
-  1,                        /* ShmOpen is disabled */
+  1,                        /* shared memory is disabled */
   semClose,                 /* xClose method */
   semLock,                  /* xLock method */
   semUnlock,                /* xUnlock method */
@@ -26225,7 +26812,7 @@
 IOMETHODS(
   afpIoFinder,              /* Finder function name */
   afpIoMethods,             /* sqlite3_io_methods object name */
-  1,                        /* ShmOpen is disabled */
+  1,                        /* shared memory is disabled */
   afpClose,                 /* xClose method */
   afpLock,                  /* xLock method */
   afpUnlock,                /* xUnlock method */
@@ -26250,7 +26837,7 @@
 IOMETHODS(
   proxyIoFinder,            /* Finder function name */
   proxyIoMethods,           /* sqlite3_io_methods object name */
-  1,                        /* ShmOpen is disabled */
+  1,                        /* shared memory is disabled */
   proxyClose,               /* xClose method */
   proxyLock,                /* xLock method */
   proxyUnlock,              /* xUnlock method */
@@ -26263,7 +26850,7 @@
 IOMETHODS(
   nfsIoFinder,               /* Finder function name */
   nfsIoMethods,              /* sqlite3_io_methods object name */
-  1,                         /* ShmOpen is disabled */
+  1,                         /* shared memory is disabled */
   unixClose,                 /* xClose method */
   unixLock,                  /* xLock method */
   nfsUnlock,                 /* xUnlock method */
@@ -26727,6 +27314,51 @@
 }
 
 /*
+** This function is called by unixOpen() to determine the unix permissions
+** to create new files with. If no error occurs, then SQLITE_OK is returned
+** and a value suitable for passing as the third argument to open(2) is
+** written to *pMode. If an IO error occurs, an SQLite error code is 
+** returned and the value of *pMode is not modified.
+**
+** If the file being opened is a temporary file, it is always created with
+** the octal permissions 0600 (read/writable by owner only). If the file
+** is a database or master journal file, it is created with the permissions 
+** mask SQLITE_DEFAULT_FILE_PERMISSIONS.
+**
+** Finally, if the file being opened is a WAL or regular journal file, then 
+** this function queries the file-system for the permissions on the 
+** corresponding database file and sets *pMode to this value. Whenever 
+** possible, WAL and journal files are created using the same permissions 
+** as the associated database file.
+*/
+static int findCreateFileMode(
+  const char *zPath,              /* Path of file (possibly) being created */
+  int flags,                      /* Flags passed as 4th argument to xOpen() */
+  mode_t *pMode                   /* OUT: Permissions to open file with */
+){
+  int rc = SQLITE_OK;             /* Return Code */
+  if( flags & (SQLITE_OPEN_WAL|SQLITE_OPEN_MAIN_JOURNAL) ){
+    char zDb[MAX_PATHNAME+1];     /* Database file path */
+    int nDb;                      /* Number of valid bytes in zDb */
+    struct stat sStat;            /* Output of stat() on database file */
+
+    nDb = sqlite3Strlen30(zPath) - ((flags & SQLITE_OPEN_WAL) ? 4 : 8);
+    memcpy(zDb, zPath, nDb);
+    zDb[nDb] = '\0';
+    if( 0==stat(zDb, &sStat) ){
+      *pMode = sStat.st_mode & 0777;
+    }else{
+      rc = SQLITE_IOERR_FSTAT;
+    }
+  }else if( flags & SQLITE_OPEN_DELETEONCLOSE ){
+    *pMode = 0600;
+  }else{
+    *pMode = SQLITE_DEFAULT_FILE_PERMISSIONS;
+  }
+  return rc;
+}
+
+/*
 ** Open the file zPath.
 ** 
 ** Previously, the SQLite OS layer used three functions in place of this
@@ -26776,9 +27408,11 @@
   ** a file-descriptor on the directory too. The first time unixSync()
   ** is called the directory file descriptor will be fsync()ed and close()d.
   */
-  int isOpenDirectory = (isCreate && 
-      (eType==SQLITE_OPEN_MASTER_JOURNAL || eType==SQLITE_OPEN_MAIN_JOURNAL)
-  );
+  int isOpenDirectory = (isCreate && (
+        eType==SQLITE_OPEN_MASTER_JOURNAL 
+     || eType==SQLITE_OPEN_MAIN_JOURNAL 
+     || eType==SQLITE_OPEN_WAL
+  ));
 
   /* If argument zPath is a NULL pointer, this function is required to open
   ** a temporary file. Use this buffer to store the file name in.
@@ -26798,17 +27432,18 @@
   assert(isExclusive==0 || isCreate);
   assert(isDelete==0 || isCreate);
 
-  /* The main DB, main journal, and master journal are never automatically
-  ** deleted. Nor are they ever temporary files.  */
+  /* The main DB, main journal, WAL file and master journal are never 
+  ** automatically deleted. Nor are they ever temporary files.  */
   assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_DB );
   assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_JOURNAL );
   assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MASTER_JOURNAL );
+  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_WAL );
 
   /* Assert that the upper layer has set one of the "file-type" flags. */
   assert( eType==SQLITE_OPEN_MAIN_DB      || eType==SQLITE_OPEN_TEMP_DB 
        || eType==SQLITE_OPEN_MAIN_JOURNAL || eType==SQLITE_OPEN_TEMP_JOURNAL 
        || eType==SQLITE_OPEN_SUBJOURNAL   || eType==SQLITE_OPEN_MASTER_JOURNAL 
-       || eType==SQLITE_OPEN_TRANSIENT_DB
+       || eType==SQLITE_OPEN_TRANSIENT_DB || eType==SQLITE_OPEN_WAL
   );
 
   memset(p, 0, sizeof(unixFile));
@@ -26846,7 +27481,13 @@
   openFlags |= (O_LARGEFILE|O_BINARY);
 
   if( fd<0 ){
-    mode_t openMode = (isDelete?0600:SQLITE_DEFAULT_FILE_PERMISSIONS);
+    mode_t openMode;              /* Permissions to create file with */
+    rc = findCreateFileMode(zName, flags, &openMode);
+    if( rc!=SQLITE_OK ){
+      assert( !p->pUnused );
+      assert( eType==SQLITE_OPEN_WAL || eType==SQLITE_OPEN_MAIN_JOURNAL );
+      return rc;
+    }
     fd = open(zName, openFlags, openMode);
     OSTRACE(("OPENX   %-3d %s 0%o\n", fd, zName, openFlags));
     if( fd<0 && errno!=EISDIR && isReadWrite && !isExclusive ){
@@ -26989,7 +27630,9 @@
   int rc = SQLITE_OK;
   UNUSED_PARAMETER(NotUsed);
   SimulateIOError(return SQLITE_IOERR_DELETE);
-  unlink(zPath);
+  if( unlink(zPath)==(-1) && errno!=ENOENT ){
+    return SQLITE_IOERR_DELETE;
+  }
 #ifndef SQLITE_DISABLE_DIRSYNC
   if( dirSync ){
     int fd;
@@ -27660,6 +28303,8 @@
   
   assert(PROXY_HOSTIDLEN == sizeof(uuid_t));
   memset(pHostID, 0, PROXY_HOSTIDLEN);
+#if defined(__MAX_OS_X_VERSION_MIN_REQUIRED)\
+               && __MAC_OS_X_VERSION_MIN_REQUIRED<1050
   if( gethostuuid(pHostID, &timeout) ){
     int err = errno;
     if( pError ){
@@ -27667,6 +28312,7 @@
     }
     return SQLITE_IOERR;
   }
+#endif
 #ifdef SQLITE_TEST
   /* simulate multiple hosts by creating unique hostid file paths */
   if( sqlite3_hostid_num != 0){
@@ -28257,7 +28903,7 @@
       pCtx->conchFile->pMethod->xClose((sqlite3_file *)pCtx->conchFile);
       sqlite3_free(pCtx->conchFile);
     }
-    sqlite3_free(pCtx->lockProxyPath);
+    sqlite3DbFree(0, pCtx->lockProxyPath);
     sqlite3_free(pCtx->conchFilePath); 
     sqlite3_free(pCtx);
   }
@@ -28448,9 +29094,9 @@
       if( rc ) return rc;
       sqlite3_free(conchFile);
     }
-    sqlite3_free(pCtx->lockProxyPath);
+    sqlite3DbFree(0, pCtx->lockProxyPath);
     sqlite3_free(pCtx->conchFilePath);
-    sqlite3_free(pCtx->dbPath);
+    sqlite3DbFree(0, pCtx->dbPath);
     /* restore the original locking context and pMethod then close it */
     pFile->lockingContext = pCtx->oldLockingContext;
     pFile->pMethod = pCtx->pOldMethod;
@@ -28896,6 +29542,7 @@
   DWORD sectorSize;       /* Sector size of the device file is on */
   winShm *pShm;           /* Instance of shared memory on this file */
   const char *zPath;      /* Full pathname of this file */
+  int szChunk;            /* Chunk size configured by FCNTL_CHUNK_SIZE */
 #if SQLITE_OS_WINCE
   WCHAR *zDeleteOnClose;  /* Name of file to delete when closing */
   HANDLE hMutex;          /* Mutex used to control access to shared lock */  
@@ -29408,6 +30055,42 @@
 ******************************************************************************/
 
 /*
+** Some microsoft compilers lack this definition.
+*/
+#ifndef INVALID_SET_FILE_POINTER
+# define INVALID_SET_FILE_POINTER ((DWORD)-1)
+#endif
+
+/*
+** Move the current position of the file handle passed as the first 
+** argument to offset iOffset within the file. If successful, return 0. 
+** Otherwise, set pFile->lastErrno and return non-zero.
+*/
+static int seekWinFile(winFile *pFile, sqlite3_int64 iOffset){
+  LONG upperBits;                 /* Most sig. 32 bits of new offset */
+  LONG lowerBits;                 /* Least sig. 32 bits of new offset */
+  DWORD dwRet;                    /* Value returned by SetFilePointer() */
+
+  upperBits = (LONG)((iOffset>>32) & 0x7fffffff);
+  lowerBits = (LONG)(iOffset & 0xffffffff);
+
+  /* API oddity: If successful, SetFilePointer() returns a dword 
+  ** containing the lower 32-bits of the new file-offset. Or, if it fails,
+  ** it returns INVALID_SET_FILE_POINTER. However according to MSDN, 
+  ** INVALID_SET_FILE_POINTER may also be a valid new offset. So to determine 
+  ** whether an error has actually occured, it is also necessary to call 
+  ** GetLastError().
+  */
+  dwRet = SetFilePointer(pFile->h, lowerBits, &upperBits, FILE_BEGIN);
+  if( (dwRet==INVALID_SET_FILE_POINTER && GetLastError()!=NO_ERROR) ){
+    pFile->lastErrno = GetLastError();
+    return 1;
+  }
+
+  return 0;
+}
+
+/*
 ** Close a file.
 **
 ** It is reported that an attempt to close a handle might sometimes
@@ -29427,6 +30110,7 @@
   OSTRACE(("CLOSE %d\n", pFile->h));
   do{
     rc = CloseHandle(pFile->h);
+    /* SimulateIOError( rc=0; cnt=MX_CLOSE_ATTEMPT; ); */
   }while( rc==0 && ++cnt < MX_CLOSE_ATTEMPT && (Sleep(100), 1) );
 #if SQLITE_OS_WINCE
 #define WINCE_DELETION_ATTEMPTS 3
@@ -29449,13 +30133,6 @@
 }
 
 /*
-** Some microsoft compilers lack this definition.
-*/
-#ifndef INVALID_SET_FILE_POINTER
-# define INVALID_SET_FILE_POINTER ((DWORD)-1)
-#endif
-
-/*
 ** Read data from a file into a buffer.  Return SQLITE_OK if all
 ** bytes were read successfully and SQLITE_IOERR if anything goes
 ** wrong.
@@ -29466,32 +30143,27 @@
   int amt,                   /* Number of bytes to read */
   sqlite3_int64 offset       /* Begin reading at this offset */
 ){
-  LONG upperBits = (LONG)((offset>>32) & 0x7fffffff);
-  LONG lowerBits = (LONG)(offset & 0xffffffff);
-  DWORD rc;
-  winFile *pFile = (winFile*)id;
-  DWORD error;
-  DWORD got;
+  winFile *pFile = (winFile*)id;  /* file handle */
+  DWORD nRead;                    /* Number of bytes actually read from file */
 
   assert( id!=0 );
   SimulateIOError(return SQLITE_IOERR_READ);
   OSTRACE(("READ %d lock=%d\n", pFile->h, pFile->locktype));
-  rc = SetFilePointer(pFile->h, lowerBits, &upperBits, FILE_BEGIN);
-  if( rc==INVALID_SET_FILE_POINTER && (error=GetLastError())!=NO_ERROR ){
-    pFile->lastErrno = error;
+
+  if( seekWinFile(pFile, offset) ){
     return SQLITE_FULL;
   }
-  if( !ReadFile(pFile->h, pBuf, amt, &got, 0) ){
+  if( !ReadFile(pFile->h, pBuf, amt, &nRead, 0) ){
     pFile->lastErrno = GetLastError();
     return SQLITE_IOERR_READ;
   }
-  if( got==(DWORD)amt ){
-    return SQLITE_OK;
-  }else{
+  if( nRead<(DWORD)amt ){
     /* Unread parts of the buffer must be zero-filled */
-    memset(&((char*)pBuf)[got], 0, amt-got);
+    memset(&((char*)pBuf)[nRead], 0, amt-nRead);
     return SQLITE_IOERR_SHORT_READ;
   }
+
+  return SQLITE_OK;
 }
 
 /*
@@ -29499,47 +30171,42 @@
 ** or some other error code on failure.
 */
 static int winWrite(
-  sqlite3_file *id,         /* File to write into */
-  const void *pBuf,         /* The bytes to be written */
-  int amt,                  /* Number of bytes to write */
-  sqlite3_int64 offset      /* Offset into the file to begin writing at */
+  sqlite3_file *id,               /* File to write into */
+  const void *pBuf,               /* The bytes to be written */
+  int amt,                        /* Number of bytes to write */
+  sqlite3_int64 offset            /* Offset into the file to begin writing at */
 ){
-  LONG upperBits = (LONG)((offset>>32) & 0x7fffffff);
-  LONG lowerBits = (LONG)(offset & 0xffffffff);
-  DWORD rc;
-  winFile *pFile = (winFile*)id;
-  DWORD error;
-  DWORD wrote = 0;
+  int rc;                         /* True if error has occured, else false */
+  winFile *pFile = (winFile*)id;  /* File handle */
 
-  assert( id!=0 );
+  assert( amt>0 );
+  assert( pFile );
   SimulateIOError(return SQLITE_IOERR_WRITE);
   SimulateDiskfullError(return SQLITE_FULL);
+
   OSTRACE(("WRITE %d lock=%d\n", pFile->h, pFile->locktype));
-  rc = SetFilePointer(pFile->h, lowerBits, &upperBits, FILE_BEGIN);
-  if( rc==INVALID_SET_FILE_POINTER && (error=GetLastError())!=NO_ERROR ){
-    pFile->lastErrno = error;
-    if( pFile->lastErrno==ERROR_HANDLE_DISK_FULL ){
-      return SQLITE_FULL;
-    }else{
-      return SQLITE_IOERR_WRITE;
+
+  rc = seekWinFile(pFile, offset);
+  if( rc==0 ){
+    u8 *aRem = (u8 *)pBuf;        /* Data yet to be written */
+    int nRem = amt;               /* Number of bytes yet to be written */
+    DWORD nWrite;                 /* Bytes written by each WriteFile() call */
+
+    while( nRem>0 && WriteFile(pFile->h, aRem, nRem, &nWrite, 0) && nWrite>0 ){
+      aRem += nWrite;
+      nRem -= nWrite;
+    }
+    if( nRem>0 ){
+      pFile->lastErrno = GetLastError();
+      rc = 1;
     }
   }
-  assert( amt>0 );
-  while(
-     amt>0
-     && (rc = WriteFile(pFile->h, pBuf, amt, &wrote, 0))!=0
-     && wrote>0
-  ){
-    amt -= wrote;
-    pBuf = &((char*)pBuf)[wrote];
-  }
-  if( !rc || amt>(int)wrote ){
-    pFile->lastErrno = GetLastError();
+
+  if( rc ){
     if( pFile->lastErrno==ERROR_HANDLE_DISK_FULL ){
       return SQLITE_FULL;
-    }else{
-      return SQLITE_IOERR_WRITE;
     }
+    return SQLITE_IOERR_WRITE;
   }
   return SQLITE_OK;
 }
@@ -29548,26 +30215,32 @@
 ** Truncate an open file to a specified size
 */
 static int winTruncate(sqlite3_file *id, sqlite3_int64 nByte){
-  LONG upperBits = (LONG)((nByte>>32) & 0x7fffffff);
-  LONG lowerBits = (LONG)(nByte & 0xffffffff);
-  DWORD dwRet;
-  winFile *pFile = (winFile*)id;
-  DWORD error;
-  int rc = SQLITE_OK;
+  winFile *pFile = (winFile*)id;  /* File handle object */
+  int rc = SQLITE_OK;             /* Return code for this function */
 
-  assert( id!=0 );
+  assert( pFile );
+
   OSTRACE(("TRUNCATE %d %lld\n", pFile->h, nByte));
   SimulateIOError(return SQLITE_IOERR_TRUNCATE);
-  dwRet = SetFilePointer(pFile->h, lowerBits, &upperBits, FILE_BEGIN);
-  if( dwRet==INVALID_SET_FILE_POINTER && (error=GetLastError())!=NO_ERROR ){
-    pFile->lastErrno = error;
+
+  /* If the user has configured a chunk-size for this file, truncate the
+  ** file so that it consists of an integer number of chunks (i.e. the
+  ** actual file size after the operation may be larger than the requested
+  ** size).
+  */
+  if( pFile->szChunk ){
+    nByte = ((nByte + pFile->szChunk - 1)/pFile->szChunk) * pFile->szChunk;
+  }
+
+  /* SetEndOfFile() returns non-zero when successful, or zero when it fails. */
+  if( seekWinFile(pFile, nByte) ){
     rc = SQLITE_IOERR_TRUNCATE;
-  /* SetEndOfFile will fail if nByte is negative */
-  }else if( !SetEndOfFile(pFile->h) ){
+  }else if( 0==SetEndOfFile(pFile->h) ){
     pFile->lastErrno = GetLastError();
     rc = SQLITE_IOERR_TRUNCATE;
   }
-  OSTRACE(("TRUNCATE %d %lld %s\n", pFile->h, nByte, rc==SQLITE_OK ? "ok" : "failed"));
+
+  OSTRACE(("TRUNCATE %d %lld %s\n", pFile->h, nByte, rc ? "failed" : "ok"));
   return rc;
 }
 
@@ -29584,14 +30257,20 @@
 ** Make sure all writes to a particular file are committed to disk.
 */
 static int winSync(sqlite3_file *id, int flags){
-#ifndef SQLITE_NO_SYNC
+#if !defined(NDEBUG) || !defined(SQLITE_NO_SYNC) || defined(SQLITE_DEBUG)
   winFile *pFile = (winFile*)id;
-
-  assert( id!=0 );
-  OSTRACE(("SYNC %d lock=%d\n", pFile->h, pFile->locktype));
 #else
   UNUSED_PARAMETER(id);
 #endif
+
+  assert( pFile );
+  /* Check that one of SQLITE_SYNC_NORMAL or FULL was passed */
+  assert((flags&0x0F)==SQLITE_SYNC_NORMAL
+      || (flags&0x0F)==SQLITE_SYNC_FULL
+  );
+
+  OSTRACE(("SYNC %d lock=%d\n", pFile->h, pFile->locktype));
+
 #ifndef SQLITE_TEST
   UNUSED_PARAMETER(flags);
 #else
@@ -29600,11 +30279,18 @@
   }
   sqlite3_sync_count++;
 #endif
+
+  /* Unix cannot, but some systems may return SQLITE_FULL from here. This
+  ** line is to test that doing so does not cause any problems.
+  */
+  SimulateDiskfullError( return SQLITE_FULL );
+  SimulateIOError( return SQLITE_IOERR; );
+
   /* If we compiled with the SQLITE_NO_SYNC flag, then syncing is a
   ** no-op
   */
 #ifdef SQLITE_NO_SYNC
-    return SQLITE_OK;
+  return SQLITE_OK;
 #else
   if( FlushFileBuffers(pFile->h) ){
     return SQLITE_OK;
@@ -29847,6 +30533,8 @@
   int rc;
   winFile *pFile = (winFile*)id;
 
+  SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
+
   assert( id!=0 );
   if( pFile->locktype>=RESERVED_LOCK ){
     rc = 1;
@@ -29917,9 +30605,15 @@
       *(int*)pArg = (int)((winFile*)id)->lastErrno;
       return SQLITE_OK;
     }
+    case SQLITE_FCNTL_CHUNK_SIZE: {
+      ((winFile*)id)->szChunk = *(int *)pArg;
+      return SQLITE_OK;
+    }
     case SQLITE_FCNTL_SIZE_HINT: {
       sqlite3_int64 sz = *(sqlite3_int64*)pArg;
+      SimulateIOErrorBenign(1);
       winTruncate(id, sz);
+      SimulateIOErrorBenign(0);
       return SQLITE_OK;
     }
   }
@@ -29949,13 +30643,16 @@
   return SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN;
 }
 
-/****************************************************************************
-********************************* Shared Memory *****************************
-**
-** The next subdivision of code manages the shared-memory primitives.
-*/
 #ifndef SQLITE_OMIT_WAL
 
+/* 
+** Windows will only let you create file view mappings
+** on allocation size granularity boundaries.
+** During sqlite3_os_init() we do a GetSystemInfo()
+** to get the granularity size.
+*/
+SYSTEM_INFO winSysInfo;
+
 /*
 ** Helper functions to obtain and relinquish the global mutex. The
 ** global mutex is used to protect the winLockInfo objects used by 
@@ -29967,7 +30664,7 @@
 **
 **   winShmEnterMutex()
 **     assert( winShmMutexHeld() );
-**   winEnterLeave()
+**   winShmLeaveMutex()
 */
 static void winShmEnterMutex(void){
   sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
@@ -30003,11 +30700,6 @@
 ** winShmMutexHeld() is true when reading or writing any other field
 ** in this structure.
 **
-** To avoid deadlocks, mutex and mutexBuf are always released in the
-** reverse order that they are acquired.  mutexBuf is always acquired
-** first and released last.  This invariant is check by asserting
-** sqlite3_mutex_notheld() on mutex whenever mutexBuf is acquired or
-** released.
 */
 struct winShmNode {
   sqlite3_mutex *mutex;      /* Mutex to access this object */
@@ -30041,17 +30733,21 @@
 ** Structure used internally by this VFS to record the state of an
 ** open shared memory connection.
 **
-** winShm.pFile->mutex must be held while reading or writing the
-** winShm.pNext and winShm.locks[] elements.
+** The following fields are initialized when this object is created and
+** are read-only thereafter:
 **
-** The winShm.pFile element is initialized when the object is created
-** and is read-only thereafter.
+**    winShm.pShmNode
+**    winShm.id
+**
+** All other fields are read/write.  The winShm.pShmNode->mutex must be held
+** while accessing any read/write fields.
 */
 struct winShm {
   winShmNode *pShmNode;      /* The underlying winShmNode object */
   winShm *pNext;             /* Next winShm with the same winShmNode */
   u8 hasMutex;               /* True if holding the winShmNode mutex */
-  u8 hasMutexBuf;            /* True if holding pFile->mutexBuf */
+  u16 sharedMask;            /* Mask of shared locks held */
+  u16 exclMask;              /* Mask of exclusive locks held */
 #ifdef SQLITE_DEBUG
   u8 id;                     /* Id of this connection with its winShmNode */
 #endif
@@ -30086,7 +30782,6 @@
   dwFlags = LOCKFILE_FAIL_IMMEDIATELY;
   if( lockType == _SHM_WRLCK ) dwFlags |= LOCKFILE_EXCLUSIVE_LOCK;
 
-  /* Find the first bit in lockMask that is set */
   memset(&ovlp, 0, sizeof(OVERLAPPED));
   ovlp.Offset = ofst;
 
@@ -30096,13 +30791,19 @@
   }else{
     rc = LockFileEx(pFile->hFile.h, dwFlags, 0, nByte, 0, &ovlp);
   }
-  if( !rc ){
-    OSTRACE(("SHM-LOCK %d %s ERROR 0x%08lx\n", 
-             pFile->hFile.h,
-             lockType==_SHM_UNLCK ? "UnlockFileEx" : "LockFileEx",
-             GetLastError()));
+  
+  if( rc!= 0 ){
+    rc = SQLITE_OK;
+  }else{
+    pFile->lastErrno =  GetLastError();
+    rc = SQLITE_BUSY;
   }
-  rc = (rc!=0) ? SQLITE_OK : SQLITE_BUSY;
+
+  OSTRACE(("SHM-LOCK %d %s %s 0x%08lx\n", 
+           pFile->hFile.h,
+           rc==SQLITE_OK ? "ok" : "failed",
+           lockType==_SHM_UNLCK ? "UnlockFileEx" : "LockFileEx",
+           pFile->lastErrno));
 
   return rc;
 }
@@ -30120,6 +30821,7 @@
 static void winShmPurge(sqlite3_vfs *pVfs, int deleteFlag){
   winShmNode **pp;
   winShmNode *p;
+  BOOL bRc;
   assert( winShmMutexHeld() );
   pp = &winShmNodeList;
   while( (p = *pp)!=0 ){
@@ -30127,13 +30829,25 @@
       int i;
       if( p->mutex ) sqlite3_mutex_free(p->mutex);
       for(i=0; i<p->nRegion; i++){
-        UnmapViewOfFile(p->aRegion[i].pMap);
-        CloseHandle(p->aRegion[i].hMap);
+        bRc = UnmapViewOfFile(p->aRegion[i].pMap);
+        OSTRACE(("SHM-PURGE pid-%d unmap region=%d %s\n",
+                 (int)GetCurrentProcessId(), i,
+                 bRc ? "ok" : "failed"));
+        bRc = CloseHandle(p->aRegion[i].hMap);
+        OSTRACE(("SHM-PURGE pid-%d close region=%d %s\n",
+                 (int)GetCurrentProcessId(), i,
+                 bRc ? "ok" : "failed"));
       }
-      if( p->hFile.h != INVALID_HANDLE_VALUE ) {
+      if( p->hFile.h != INVALID_HANDLE_VALUE ){
+        SimulateIOErrorBenign(1);
         winClose((sqlite3_file *)&p->hFile);
+        SimulateIOErrorBenign(0);
       }
-      if( deleteFlag ) winDelete(pVfs, p->zFilename, 0);
+      if( deleteFlag ){
+        SimulateIOErrorBenign(1);
+        winDelete(pVfs, p->zFilename, 0);
+        SimulateIOErrorBenign(0);
+      }
       *pp = p->pNext;
       sqlite3_free(p->aRegion);
       sqlite3_free(p);
@@ -30144,31 +30858,19 @@
 }
 
 /*
-** Open a shared-memory area.  This particular implementation uses
-** mmapped files.
-**
-** zName is a filename used to identify the shared-memory area.  The
-** implementation does not (and perhaps should not) use this name
-** directly, but rather use it as a template for finding an appropriate
-** name for the shared-memory storage.  In this implementation, the
-** string "-index" is appended to zName and used as the name of the
-** mmapped file.
+** Open the shared-memory area associated with database file pDbFd.
 **
 ** When opening a new shared-memory file, if no other instances of that
 ** file are currently open, in this process or in other processes, then
 ** the file must be truncated to zero length or have its header cleared.
 */
-static int winShmOpen(
-  sqlite3_file *fd      /* The file to which to attach shared memory */
-){
-  struct winFile *pDbFd;             /* Database to which to attach SHM */
+static int winOpenSharedMemory(winFile *pDbFd){
   struct winShm *p;                  /* The connection to be opened */
   struct winShmNode *pShmNode = 0;   /* The underlying mmapped file */
   int rc;                            /* Result code */
   struct winShmNode *pNew;           /* Newly allocated winShmNode */
   int nName;                         /* Size of zName in bytes */
 
-  pDbFd = (winFile*)fd;
   assert( pDbFd->pShm==0 );    /* Not previously opened */
 
   /* Allocate space for the new sqlite3_shm object.  Also speculatively
@@ -30211,10 +30913,11 @@
       rc = SQLITE_NOMEM;
       goto shm_open_err;
     }
+
     rc = winOpen(pDbFd->pVfs,
                  pShmNode->zFilename,             /* Name of the file (UTF-8) */
                  (sqlite3_file*)&pShmNode->hFile,  /* File handle here */
-                 SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE, /* Mode flags */
+                 SQLITE_OPEN_WAL | SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE, /* Mode flags */
                  0);
     if( SQLITE_OK!=rc ){
       rc = SQLITE_CANTOPEN_BKPT;
@@ -30239,14 +30942,24 @@
 
   /* Make the new connection a child of the winShmNode */
   p->pShmNode = pShmNode;
-  p->pNext = pShmNode->pFirst;
 #ifdef SQLITE_DEBUG
   p->id = pShmNode->nextShmId++;
 #endif
-  pShmNode->pFirst = p;
   pShmNode->nRef++;
   pDbFd->pShm = p;
   winShmLeaveMutex();
+
+  /* The reference count on pShmNode has already been incremented under
+  ** the cover of the winShmEnterMutex() mutex and the pointer from the
+  ** new (struct winShm) object to the pShmNode has been set. All that is
+  ** left to do is to link the new object into the linked list starting
+  ** at pShmNode->pFirst. This must be done while holding the pShmNode->mutex 
+  ** mutex.
+  */
+  sqlite3_mutex_enter(pShmNode->mutex);
+  p->pNext = pShmNode->pFirst;
+  pShmNode->pFirst = p;
+  sqlite3_mutex_leave(pShmNode->mutex);
   return SQLITE_OK;
 
   /* Jump here on any error */
@@ -30263,7 +30976,7 @@
 ** Close a connection to shared-memory.  Delete the underlying 
 ** storage if deleteFlag is true.
 */
-static int winShmClose(
+static int winShmUnmap(
   sqlite3_file *fd,          /* Database holding shared memory */
   int deleteFlag             /* Delete after closing if true */
 ){
@@ -30274,6 +30987,7 @@
 
   pDbFd = (winFile*)fd;
   p = pDbFd->pShm;
+  if( p==0 ) return SQLITE_OK;
   pShmNode = p->pShmNode;
 
   /* Remove connection p from the set of connections associated
@@ -30301,6 +31015,127 @@
 }
 
 /*
+** Change the lock state for a shared-memory segment.
+*/
+static int winShmLock(
+  sqlite3_file *fd,          /* Database file holding the shared memory */
+  int ofst,                  /* First lock to acquire or release */
+  int n,                     /* Number of locks to acquire or release */
+  int flags                  /* What to do with the lock */
+){
+  winFile *pDbFd = (winFile*)fd;        /* Connection holding shared memory */
+  winShm *p = pDbFd->pShm;              /* The shared memory being locked */
+  winShm *pX;                           /* For looping over all siblings */
+  winShmNode *pShmNode = p->pShmNode;
+  int rc = SQLITE_OK;                   /* Result code */
+  u16 mask;                             /* Mask of locks to take or release */
+
+  assert( ofst>=0 && ofst+n<=SQLITE_SHM_NLOCK );
+  assert( n>=1 );
+  assert( flags==(SQLITE_SHM_LOCK | SQLITE_SHM_SHARED)
+       || flags==(SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE)
+       || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED)
+       || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE) );
+  assert( n==1 || (flags & SQLITE_SHM_EXCLUSIVE)!=0 );
+
+  mask = (u16)((1U<<(ofst+n)) - (1U<<ofst));
+  assert( n>1 || mask==(1<<ofst) );
+  sqlite3_mutex_enter(pShmNode->mutex);
+  if( flags & SQLITE_SHM_UNLOCK ){
+    u16 allMask = 0; /* Mask of locks held by siblings */
+
+    /* See if any siblings hold this same lock */
+    for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
+      if( pX==p ) continue;
+      assert( (pX->exclMask & (p->exclMask|p->sharedMask))==0 );
+      allMask |= pX->sharedMask;
+    }
+
+    /* Unlock the system-level locks */
+    if( (mask & allMask)==0 ){
+      rc = winShmSystemLock(pShmNode, _SHM_UNLCK, ofst+WIN_SHM_BASE, n);
+    }else{
+      rc = SQLITE_OK;
+    }
+
+    /* Undo the local locks */
+    if( rc==SQLITE_OK ){
+      p->exclMask &= ~mask;
+      p->sharedMask &= ~mask;
+    } 
+  }else if( flags & SQLITE_SHM_SHARED ){
+    u16 allShared = 0;  /* Union of locks held by connections other than "p" */
+
+    /* Find out which shared locks are already held by sibling connections.
+    ** If any sibling already holds an exclusive lock, go ahead and return
+    ** SQLITE_BUSY.
+    */
+    for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
+      if( (pX->exclMask & mask)!=0 ){
+        rc = SQLITE_BUSY;
+        break;
+      }
+      allShared |= pX->sharedMask;
+    }
+
+    /* Get shared locks at the system level, if necessary */
+    if( rc==SQLITE_OK ){
+      if( (allShared & mask)==0 ){
+        rc = winShmSystemLock(pShmNode, _SHM_RDLCK, ofst+WIN_SHM_BASE, n);
+      }else{
+        rc = SQLITE_OK;
+      }
+    }
+
+    /* Get the local shared locks */
+    if( rc==SQLITE_OK ){
+      p->sharedMask |= mask;
+    }
+  }else{
+    /* Make sure no sibling connections hold locks that will block this
+    ** lock.  If any do, return SQLITE_BUSY right away.
+    */
+    for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
+      if( (pX->exclMask & mask)!=0 || (pX->sharedMask & mask)!=0 ){
+        rc = SQLITE_BUSY;
+        break;
+      }
+    }
+  
+    /* Get the exclusive locks at the system level.  Then if successful
+    ** also mark the local connection as being locked.
+    */
+    if( rc==SQLITE_OK ){
+      rc = winShmSystemLock(pShmNode, _SHM_WRLCK, ofst+WIN_SHM_BASE, n);
+      if( rc==SQLITE_OK ){
+        assert( (p->sharedMask & mask)==0 );
+        p->exclMask |= mask;
+      }
+    }
+  }
+  sqlite3_mutex_leave(pShmNode->mutex);
+  OSTRACE(("SHM-LOCK shmid-%d, pid-%d got %03x,%03x %s\n",
+           p->id, (int)GetCurrentProcessId(), p->sharedMask, p->exclMask,
+           rc ? "failed" : "ok"));
+  return rc;
+}
+
+/*
+** Implement a memory barrier or memory fence on shared memory.  
+**
+** All loads and stores begun before the barrier must complete before
+** any load or store begun after the barrier.
+*/
+static void winShmBarrier(
+  sqlite3_file *fd          /* Database holding the shared memory */
+){
+  UNUSED_PARAMETER(fd);
+  /* MemoryBarrier(); // does not work -- do not know why not */
+  winShmEnterMutex();
+  winShmLeaveMutex();
+}
+
+/*
 ** This function is called to obtain a pointer to region iRegion of the 
 ** shared-memory associated with the database file fd. Shared-memory regions 
 ** are numbered starting from zero. Each shared-memory region is szRegion 
@@ -30328,9 +31163,16 @@
 ){
   winFile *pDbFd = (winFile*)fd;
   winShm *p = pDbFd->pShm;
-  winShmNode *pShmNode = p->pShmNode;
+  winShmNode *pShmNode;
   int rc = SQLITE_OK;
 
+  if( !p ){
+    rc = winOpenSharedMemory(pDbFd);
+    if( rc!=SQLITE_OK ) return rc;
+    p = pDbFd->pShm;
+  }
+  pShmNode = p->pShmNode;
+
   sqlite3_mutex_enter(pShmNode->mutex);
   assert( szRegion==pShmNode->szRegion || pShmNode->nRegion==0 );
 
@@ -30347,6 +31189,7 @@
     */
     rc = winFileSize((sqlite3_file *)&pShmNode->hFile, &sz);
     if( rc!=SQLITE_OK ){
+      rc = SQLITE_IOERR_SHMSIZE;
       goto shmpage_out;
     }
 
@@ -30360,6 +31203,7 @@
       if( !isWrite ) goto shmpage_out;
       rc = winTruncate((sqlite3_file *)&pShmNode->hFile, nByte);
       if( rc!=SQLITE_OK ){
+        rc = SQLITE_IOERR_SHMSIZE;
         goto shmpage_out;
       }
     }
@@ -30381,10 +31225,18 @@
       hMap = CreateFileMapping(pShmNode->hFile.h, 
           NULL, PAGE_READWRITE, 0, nByte, NULL
       );
+      OSTRACE(("SHM-MAP pid-%d create region=%d nbyte=%d %s\n",
+               (int)GetCurrentProcessId(), pShmNode->nRegion, nByte,
+               hMap ? "ok" : "failed"));
       if( hMap ){
+        int iOffset = pShmNode->nRegion*szRegion;
+        int iOffsetShift = iOffset % winSysInfo.dwAllocationGranularity;
         pMap = MapViewOfFile(hMap, FILE_MAP_WRITE | FILE_MAP_READ,
-            0, 0, nByte
+            0, iOffset - iOffsetShift, szRegion + iOffsetShift
         );
+        OSTRACE(("SHM-MAP pid-%d map region=%d offset=%d size=%d %s\n",
+                 (int)GetCurrentProcessId(), pShmNode->nRegion, iOffset, szRegion,
+                 pMap ? "ok" : "failed"));
       }
       if( !pMap ){
         pShmNode->lastErrno = GetLastError();
@@ -30401,8 +31253,10 @@
 
 shmpage_out:
   if( pShmNode->nRegion>iRegion ){
+    int iOffset = iRegion*szRegion;
+    int iOffsetShift = iOffset % winSysInfo.dwAllocationGranularity;
     char *p = (char *)pShmNode->aRegion[iRegion].pMap;
-    *pp = (void *)&p[iRegion*szRegion];
+    *pp = (void *)&p[iOffsetShift];
   }else{
     *pp = 0;
   }
@@ -30410,98 +31264,49 @@
   return rc;
 }
 
-/*
-** Change the lock state for a shared-memory segment.
-*/
-static int winShmLock(
-  sqlite3_file *fd,          /* Database file holding the shared memory */
-  int ofst,                  /* First lock to acquire or release */
-  int n,                     /* Number of locks to acquire or release */
-  int flags                  /* What to do with the lock */
-){
-  winFile *pDbFd = (winFile*)fd;
-  winShm *p = pDbFd->pShm;
-  winShmNode *pShmNode = p->pShmNode;
-  int rc = SQLITE_PROTOCOL;
-
-  assert( ofst>=0 && ofst+n<=SQLITE_SHM_NLOCK );
-  assert( n>=1 );
-  assert( flags==(SQLITE_SHM_LOCK | SQLITE_SHM_SHARED)
-       || flags==(SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE)
-       || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED)
-       || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE) );
-  assert( n==1 || (flags & SQLITE_SHM_EXCLUSIVE)!=0 );
-
-  sqlite3_mutex_enter(pShmNode->mutex);
-  if( flags & SQLITE_SHM_UNLOCK ){
-    rc = winShmSystemLock(pShmNode, _SHM_UNLCK, ofst+WIN_SHM_BASE, n);
-  }else if( flags & SQLITE_SHM_SHARED ){
-    rc = winShmSystemLock(pShmNode, _SHM_RDLCK, ofst+WIN_SHM_BASE, n);
-  }else{
-    rc = winShmSystemLock(pShmNode, _SHM_WRLCK, ofst+WIN_SHM_BASE, n);
-  }
-  sqlite3_mutex_leave(pShmNode->mutex);
-  OSTRACE(("SHM-LOCK shmid-%d, pid-%d %s\n",
-           p->id, (int)GetCurrentProcessId(), rc ? "failed" : "ok"));
-  return rc;
-}
-
-/*
-** Implement a memory barrier or memory fence on shared memory.  
-**
-** All loads and stores begun before the barrier must complete before
-** any load or store begun after the barrier.
-*/
-static void winShmBarrier(
-  sqlite3_file *fd          /* Database holding the shared memory */
-){
-  UNUSED_PARAMETER(fd);
-  /* MemoryBarrier(); // does not work -- do not know why not */
-  winShmEnterMutex();
-  winShmLeaveMutex();
-}
-
 #else
-# define winShmOpen    0
 # define winShmMap     0
 # define winShmLock    0
 # define winShmBarrier 0
-# define winShmClose   0
+# define winShmUnmap   0
 #endif /* #ifndef SQLITE_OMIT_WAL */
+
 /*
-***************************** End Shared Memory *****************************
-****************************************************************************/
+** Here ends the implementation of all sqlite3_file methods.
+**
+********************** End sqlite3_file Methods *******************************
+******************************************************************************/
 
 /*
 ** This vector defines all the methods that can operate on an
 ** sqlite3_file for win32.
 */
 static const sqlite3_io_methods winIoMethod = {
-  2,                        /* iVersion */
-  winClose,
-  winRead,
-  winWrite,
-  winTruncate,
-  winSync,
-  winFileSize,
-  winLock,
-  winUnlock,
-  winCheckReservedLock,
-  winFileControl,
-  winSectorSize,
-  winDeviceCharacteristics,
-  winShmOpen,              /* xShmOpen */
-  winShmLock,              /* xShmLock */
-  winShmMap,               /* xShmMap */
-  winShmBarrier,           /* xShmBarrier */
-  winShmClose              /* xShmClose */
+  2,                              /* iVersion */
+  winClose,                       /* xClose */
+  winRead,                        /* xRead */
+  winWrite,                       /* xWrite */
+  winTruncate,                    /* xTruncate */
+  winSync,                        /* xSync */
+  winFileSize,                    /* xFileSize */
+  winLock,                        /* xLock */
+  winUnlock,                      /* xUnlock */
+  winCheckReservedLock,           /* xCheckReservedLock */
+  winFileControl,                 /* xFileControl */
+  winSectorSize,                  /* xSectorSize */
+  winDeviceCharacteristics,       /* xDeviceCharacteristics */
+  winShmMap,                      /* xShmMap */
+  winShmLock,                     /* xShmLock */
+  winShmBarrier,                  /* xShmBarrier */
+  winShmUnmap                     /* xShmUnmap */
 };
 
-/***************************************************************************
-** Here ends the I/O methods that form the sqlite3_io_methods object.
+/****************************************************************************
+**************************** sqlite3_vfs methods ****************************
 **
-** The next block of code implements the VFS methods.
-****************************************************************************/
+** This division contains the implementation of methods on the
+** sqlite3_vfs object.
+*/
 
 /*
 ** Convert a UTF-8 filename into whatever form the underlying
@@ -30535,6 +31340,13 @@
     "0123456789";
   size_t i, j;
   char zTempPath[MAX_PATH+1];
+
+  /* It's odd to simulate an io-error here, but really this is just
+  ** using the io-error infrastructure to test that SQLite handles this
+  ** function failing. 
+  */
+  SimulateIOError( return SQLITE_IOERR );
+
   if( sqlite3_temp_directory ){
     sqlite3_snprintf(MAX_PATH-30, zTempPath, "%s", sqlite3_temp_directory);
   }else if( isNT() ){
@@ -30566,16 +31378,26 @@
     }
 #endif
   }
+
+  /* Check that the output buffer is large enough for the temporary file 
+  ** name. If it is not, return SQLITE_ERROR.
+  */
+  if( (sqlite3Strlen30(zTempPath) + sqlite3Strlen30(SQLITE_TEMP_FILE_PREFIX) + 17) >= nBuf ){
+    return SQLITE_ERROR;
+  }
+
   for(i=sqlite3Strlen30(zTempPath); i>0 && zTempPath[i-1]=='\\'; i--){}
   zTempPath[i] = 0;
-  sqlite3_snprintf(nBuf-30, zBuf,
+
+  sqlite3_snprintf(nBuf-17, zBuf,
                    "%s\\"SQLITE_TEMP_FILE_PREFIX, zTempPath);
   j = sqlite3Strlen30(zBuf);
-  sqlite3_randomness(20, &zBuf[j]);
-  for(i=0; i<20; i++, j++){
+  sqlite3_randomness(15, &zBuf[j]);
+  for(i=0; i<15; i++, j++){
     zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
   }
   zBuf[j] = 0;
+
   OSTRACE(("TEMP FILENAME: %s\n", zBuf));
   return SQLITE_OK; 
 }
@@ -30661,9 +31483,60 @@
   int isTemp = 0;
 #endif
   winFile *pFile = (winFile*)id;
-  void *zConverted;                 /* Filename in OS encoding */
-  const char *zUtf8Name = zName;    /* Filename in UTF-8 encoding */
-  char zTmpname[MAX_PATH+1];        /* Buffer used to create temp filename */
+  void *zConverted;              /* Filename in OS encoding */
+  const char *zUtf8Name = zName; /* Filename in UTF-8 encoding */
+
+  /* If argument zPath is a NULL pointer, this function is required to open
+  ** a temporary file. Use this buffer to store the file name in.
+  */
+  char zTmpname[MAX_PATH+1];     /* Buffer used to create temp filename */
+
+  int rc = SQLITE_OK;            /* Function Return Code */
+#if !defined(NDEBUG) || SQLITE_OS_WINCE
+  int eType = flags&0xFFFFFF00;  /* Type of file to open */
+#endif
+
+  int isExclusive  = (flags & SQLITE_OPEN_EXCLUSIVE);
+  int isDelete     = (flags & SQLITE_OPEN_DELETEONCLOSE);
+  int isCreate     = (flags & SQLITE_OPEN_CREATE);
+#ifndef NDEBUG
+  int isReadonly   = (flags & SQLITE_OPEN_READONLY);
+#endif
+  int isReadWrite  = (flags & SQLITE_OPEN_READWRITE);
+
+#ifndef NDEBUG
+  int isOpenJournal = (isCreate && (
+        eType==SQLITE_OPEN_MASTER_JOURNAL 
+     || eType==SQLITE_OPEN_MAIN_JOURNAL 
+     || eType==SQLITE_OPEN_WAL
+  ));
+#endif
+
+  /* Check the following statements are true: 
+  **
+  **   (a) Exactly one of the READWRITE and READONLY flags must be set, and 
+  **   (b) if CREATE is set, then READWRITE must also be set, and
+  **   (c) if EXCLUSIVE is set, then CREATE must also be set.
+  **   (d) if DELETEONCLOSE is set, then CREATE must also be set.
+  */
+  assert((isReadonly==0 || isReadWrite==0) && (isReadWrite || isReadonly));
+  assert(isCreate==0 || isReadWrite);
+  assert(isExclusive==0 || isCreate);
+  assert(isDelete==0 || isCreate);
+
+  /* The main DB, main journal, WAL file and master journal are never 
+  ** automatically deleted. Nor are they ever temporary files.  */
+  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_DB );
+  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_JOURNAL );
+  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MASTER_JOURNAL );
+  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_WAL );
+
+  /* Assert that the upper layer has set one of the "file-type" flags. */
+  assert( eType==SQLITE_OPEN_MAIN_DB      || eType==SQLITE_OPEN_TEMP_DB 
+       || eType==SQLITE_OPEN_MAIN_JOURNAL || eType==SQLITE_OPEN_TEMP_JOURNAL 
+       || eType==SQLITE_OPEN_SUBJOURNAL   || eType==SQLITE_OPEN_MASTER_JOURNAL 
+       || eType==SQLITE_OPEN_TRANSIENT_DB || eType==SQLITE_OPEN_WAL
+  );
 
   assert( id!=0 );
   UNUSED_PARAMETER(pVfs);
@@ -30674,7 +31547,8 @@
   ** temporary file name to use 
   */
   if( !zUtf8Name ){
-    int rc = getTempname(MAX_PATH+1, zTmpname);
+    assert(isDelete && !isOpenJournal);
+    rc = getTempname(MAX_PATH+1, zTmpname);
     if( rc!=SQLITE_OK ){
       return rc;
     }
@@ -30687,29 +31561,31 @@
     return SQLITE_NOMEM;
   }
 
-  if( flags & SQLITE_OPEN_READWRITE ){
+  if( isReadWrite ){
     dwDesiredAccess = GENERIC_READ | GENERIC_WRITE;
   }else{
     dwDesiredAccess = GENERIC_READ;
   }
+
   /* SQLITE_OPEN_EXCLUSIVE is used to make sure that a new file is 
   ** created. SQLite doesn't use it to indicate "exclusive access" 
   ** as it is usually understood.
   */
-  assert(!(flags & SQLITE_OPEN_EXCLUSIVE) || (flags & SQLITE_OPEN_CREATE));
-  if( flags & SQLITE_OPEN_EXCLUSIVE ){
+  if( isExclusive ){
     /* Creates a new file, only if it does not already exist. */
     /* If the file exists, it fails. */
     dwCreationDisposition = CREATE_NEW;
-  }else if( flags & SQLITE_OPEN_CREATE ){
+  }else if( isCreate ){
     /* Open existing file, or create if it doesn't exist */
     dwCreationDisposition = OPEN_ALWAYS;
   }else{
     /* Opens a file, only if it exists. */
     dwCreationDisposition = OPEN_EXISTING;
   }
+
   dwShareMode = FILE_SHARE_READ | FILE_SHARE_WRITE;
-  if( flags & SQLITE_OPEN_DELETEONCLOSE ){
+
+  if( isDelete ){
 #if SQLITE_OS_WINCE
     dwFlagsAndAttributes = FILE_ATTRIBUTE_HIDDEN;
     isTemp = 1;
@@ -30726,6 +31602,7 @@
 #if SQLITE_OS_WINCE
   dwFlagsAndAttributes |= FILE_FLAG_RANDOM_ACCESS;
 #endif
+
   if( isNT() ){
     h = CreateFileW((WCHAR*)zConverted,
        dwDesiredAccess,
@@ -30751,25 +31628,30 @@
     );
 #endif
   }
+
   OSTRACE(("OPEN %d %s 0x%lx %s\n", 
            h, zName, dwDesiredAccess, 
            h==INVALID_HANDLE_VALUE ? "failed" : "ok"));
+
   if( h==INVALID_HANDLE_VALUE ){
+    pFile->lastErrno = GetLastError();
     free(zConverted);
-    if( flags & SQLITE_OPEN_READWRITE ){
+    if( isReadWrite ){
       return winOpen(pVfs, zName, id, 
-             ((flags|SQLITE_OPEN_READONLY)&~SQLITE_OPEN_READWRITE), pOutFlags);
+             ((flags|SQLITE_OPEN_READONLY)&~(SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE)), pOutFlags);
     }else{
       return SQLITE_CANTOPEN_BKPT;
     }
   }
+
   if( pOutFlags ){
-    if( flags & SQLITE_OPEN_READWRITE ){
+    if( isReadWrite ){
       *pOutFlags = SQLITE_OPEN_READWRITE;
     }else{
       *pOutFlags = SQLITE_OPEN_READONLY;
     }
   }
+
   memset(pFile, 0, sizeof(*pFile));
   pFile->pMethod = &winIoMethod;
   pFile->h = h;
@@ -30778,9 +31660,9 @@
   pFile->pShm = 0;
   pFile->zPath = zName;
   pFile->sectorSize = getSectorSize(pVfs, zUtf8Name);
+
 #if SQLITE_OS_WINCE
-  if( (flags & (SQLITE_OPEN_READWRITE|SQLITE_OPEN_MAIN_DB)) ==
-               (SQLITE_OPEN_READWRITE|SQLITE_OPEN_MAIN_DB)
+  if( isReadWrite && eType==SQLITE_OPEN_MAIN_DB
        && !winceCreateLock(zName, pFile)
   ){
     CloseHandle(h);
@@ -30794,8 +31676,9 @@
   {
     free(zConverted);
   }
+
   OpenCounter(+1);
-  return SQLITE_OK;
+  return rc;
 }
 
 /*
@@ -30819,13 +31702,15 @@
   int cnt = 0;
   DWORD rc;
   DWORD error = 0;
-  void *zConverted = convertUtf8Filename(zFilename);
+  void *zConverted;
   UNUSED_PARAMETER(pVfs);
   UNUSED_PARAMETER(syncDir);
+
+  SimulateIOError(return SQLITE_IOERR_DELETE);
+  zConverted = convertUtf8Filename(zFilename);
   if( zConverted==0 ){
     return SQLITE_NOMEM;
   }
-  SimulateIOError(return SQLITE_IOERR_DELETE);
   if( isNT() ){
     do{
       DeleteFileW(zConverted);
@@ -30938,12 +31823,14 @@
 ){
   
 #if defined(__CYGWIN__)
+  SimulateIOError( return SQLITE_ERROR );
   UNUSED_PARAMETER(nFull);
   cygwin_conv_to_full_win32_path(zRelative, zFull);
   return SQLITE_OK;
 #endif
 
 #if SQLITE_OS_WINCE
+  SimulateIOError( return SQLITE_ERROR );
   UNUSED_PARAMETER(nFull);
   /* WinCE has no concept of a relative pathname, or so I am told. */
   sqlite3_snprintf(pVfs->mxPathname, zFull, "%s", zRelative);
@@ -30954,6 +31841,13 @@
   int nByte;
   void *zConverted;
   char *zOut;
+
+  /* It's odd to simulate an io-error here, but really this is just
+  ** using the io-error infrastructure to test that SQLite handles this
+  ** function failing. This function could fail if, for example, the
+  ** current working directory has been unlinked.
+  */
+  SimulateIOError( return SQLITE_ERROR );
   UNUSED_PARAMETER(nFull);
   zConverted = convertUtf8Filename(zRelative);
   if( isNT() ){
@@ -31021,7 +31915,9 @@
   ** to get the drive letter to look up the sector
   ** size.
   */
+  SimulateIOErrorBenign(1);
   rc = winFullPathname(pVfs, zRelative, MAX_PATH, zFullpath);
+  SimulateIOErrorBenign(0);
   if( rc == SQLITE_OK )
   {
     void *zConverted = convertUtf8Filename(zFullpath);
@@ -31301,6 +32197,13 @@
     winCurrentTimeInt64, /* xCurrentTimeInt64 */
   };
 
+#ifndef SQLITE_OMIT_WAL
+  /* get memory map allocation granularity */
+  memset(&winSysInfo, 0, sizeof(SYSTEM_INFO));
+  GetSystemInfo(&winSysInfo);
+  assert(winSysInfo.dwAllocationGranularity > 0);
+#endif
+
   sqlite3_vfs_register(&winVfs, 1);
   return SQLITE_OK; 
 }
@@ -31350,7 +32253,7 @@
 */
 
 /* Size of the Bitvec structure in bytes. */
-#define BITVEC_SZ        (sizeof(void*)*128)  /* 512 on 32bit.  1024 on 64bit */
+#define BITVEC_SZ        512
 
 /* Round the union size down to the nearest pointer boundary, since that's how 
 ** it will be aligned within the Bitvec struct. */
@@ -31865,12 +32768,16 @@
 */
 SQLITE_PRIVATE int sqlite3PcacheInitialize(void){
   if( sqlite3GlobalConfig.pcache.xInit==0 ){
+    /* IMPLEMENTATION-OF: R-26801-64137 If the xInit() method is NULL, then the
+    ** built-in default page cache is used instead of the application defined
+    ** page cache. */
     sqlite3PCacheSetDefault();
   }
   return sqlite3GlobalConfig.pcache.xInit(sqlite3GlobalConfig.pcache.pArg);
 }
 SQLITE_PRIVATE void sqlite3PcacheShutdown(void){
   if( sqlite3GlobalConfig.pcache.xShutdown ){
+    /* IMPLEMENTATION-OF: R-26000-56589 The xShutdown() method may be NULL. */
     sqlite3GlobalConfig.pcache.xShutdown(sqlite3GlobalConfig.pcache.pArg);
   }
 }
@@ -32331,8 +33238,13 @@
 typedef struct PgHdr1 PgHdr1;
 typedef struct PgFreeslot PgFreeslot;
 
-/* Pointers to structures of this type are cast and returned as 
-** opaque sqlite3_pcache* handles
+/* Each page cache is an instance of the following object.  Every
+** open database file (including each in-memory database and each
+** temporary or transient database) has a single page cache which
+** is an instance of this object.
+**
+** Pointers to structures of this type are cast and returned as 
+** opaque sqlite3_pcache* handles.
 */
 struct PCache1 {
   /* Cache configuration parameters. Page size (szPage) and the purgeable
@@ -32392,6 +33304,9 @@
 
   /* Variables related to SQLITE_CONFIG_PAGECACHE settings. */
   int szSlot;                         /* Size of each free slot */
+  int nSlot;                          /* The number of pcache slots */
+  int nFreeSlot;                      /* Number of unused pcache slots */
+  int nReserve;                       /* Try to keep nFreeSlot above this */
   void *pStart, *pEnd;                /* Bounds of pagecache malloc range */
   PgFreeslot *pFree;                  /* Free page blocks */
   int isInit;                         /* True if initialized */
@@ -32439,6 +33354,8 @@
     PgFreeslot *p;
     sz = ROUNDDOWN8(sz);
     pcache1.szSlot = sz;
+    pcache1.nSlot = pcache1.nFreeSlot = n;
+    pcache1.nReserve = n>90 ? 10 : (n/10 + 1);
     pcache1.pStart = pBuf;
     pcache1.pFree = 0;
     while( n-- ){
@@ -32460,11 +33377,13 @@
 static void *pcache1Alloc(int nByte){
   void *p;
   assert( sqlite3_mutex_held(pcache1.mutex) );
+  sqlite3StatusSet(SQLITE_STATUS_PAGECACHE_SIZE, nByte);
   if( nByte<=pcache1.szSlot && pcache1.pFree ){
     assert( pcache1.isInit );
     p = (PgHdr1 *)pcache1.pFree;
     pcache1.pFree = pcache1.pFree->pNext;
-    sqlite3StatusSet(SQLITE_STATUS_PAGECACHE_SIZE, nByte);
+    pcache1.nFreeSlot--;
+    assert( pcache1.nFreeSlot>=0 );
     sqlite3StatusAdd(SQLITE_STATUS_PAGECACHE_USED, 1);
   }else{
 
@@ -32498,6 +33417,8 @@
     pSlot = (PgFreeslot*)p;
     pSlot->pNext = pcache1.pFree;
     pcache1.pFree = pSlot;
+    pcache1.nFreeSlot++;
+    assert( pcache1.nFreeSlot<=pcache1.nSlot );
   }else{
     int iSize;
     assert( sqlite3MemdebugHasType(p, MEMTYPE_PCACHE) );
@@ -32508,6 +33429,25 @@
   }
 }
 
+#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
+/*
+** Return the size of a pcache allocation
+*/
+static int pcache1MemSize(void *p){
+  assert( sqlite3_mutex_held(pcache1.mutex) );
+  if( p>=pcache1.pStart && p<pcache1.pEnd ){
+    return pcache1.szSlot;
+  }else{
+    int iSize;
+    assert( sqlite3MemdebugHasType(p, MEMTYPE_PCACHE) );
+    sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
+    iSize = sqlite3MallocSize(p);
+    sqlite3MemdebugSetType(p, MEMTYPE_PCACHE);
+    return iSize;
+  }
+}
+#endif /* SQLITE_ENABLE_MEMORY_MANAGEMENT */
+
 /*
 ** Allocate a new page object initially associated with cache pCache.
 */
@@ -32564,6 +33504,32 @@
   pcache1LeaveMutex();
 }
 
+
+/*
+** Return true if it desirable to avoid allocating a new page cache
+** entry.
+**
+** If memory was allocated specifically to the page cache using
+** SQLITE_CONFIG_PAGECACHE but that memory has all been used, then
+** it is desirable to avoid allocating a new page cache entry because
+** presumably SQLITE_CONFIG_PAGECACHE was suppose to be sufficient
+** for all page cache needs and we should not need to spill the
+** allocation onto the heap.
+**
+** Or, the heap is used for all page cache memory put the heap is
+** under memory pressure, then again it is desirable to avoid
+** allocating a new page cache entry in order to avoid stressing
+** the heap even further.
+*/
+static int pcache1UnderMemoryPressure(PCache1 *pCache){
+  assert( sqlite3_mutex_held(pcache1.mutex) );
+  if( pcache1.nSlot && pCache->szPage<=pcache1.szSlot ){
+    return pcache1.nFreeSlot<pcache1.nReserve;
+  }else{
+    return sqlite3HeapNearlyFull();
+  }
+}
+
 /******************************************************************************/
 /******** General Implementation Functions ************************************/
 
@@ -32805,14 +33771,16 @@
 **   2. If createFlag==0 and the page is not already in the cache, NULL is
 **      returned.
 **
-**   3. If createFlag is 1, and the page is not already in the cache,
-**      and if either of the following are true, return NULL:
+**   3. If createFlag is 1, and the page is not already in the cache, then
+**      return NULL (do not allocate a new page) if any of the following
+**      conditions are true:
 **
 **       (a) the number of pages pinned by the cache is greater than
 **           PCache1.nMax, or
+**
 **       (b) the number of pages pinned by the cache is greater than
 **           the sum of nMax for all purgeable caches, less the sum of 
-**           nMin for all other purgeable caches. 
+**           nMin for all other purgeable caches, or
 **
 **   4. If none of the first three conditions apply and the cache is marked
 **      as purgeable, and if one of the following is true:
@@ -32824,6 +33792,9 @@
 **           already equal to or greater than the sum of nMax for all
 **           purgeable caches,
 **
+**       (c) The system is under memory pressure and wants to avoid
+**           unnecessary pages cache entry allocations
+**
 **      then attempt to recycle a page from the LRU list. If it is the right
 **      size, return the recycled buffer. Otherwise, free the buffer and
 **      proceed to step 5. 
@@ -32855,6 +33826,7 @@
   if( createFlag==1 && (
         nPinned>=(pcache1.nMaxPage+pCache->nMin-pcache1.nMinPage)
      || nPinned>=(pCache->nMax * 9 / 10)
+     || pcache1UnderMemoryPressure(pCache)
   )){
     goto fetch_out;
   }
@@ -32865,7 +33837,9 @@
 
   /* Step 4. Try to recycle a page buffer if appropriate. */
   if( pCache->bPurgeable && pcache1.pLruTail && (
-     (pCache->nPage+1>=pCache->nMax) || pcache1.nCurrentPage>=pcache1.nMaxPage
+         (pCache->nPage+1>=pCache->nMax)
+      || pcache1.nCurrentPage>=pcache1.nMaxPage
+      || pcache1UnderMemoryPressure(pCache)
   )){
     pPage = pcache1.pLruTail;
     pcache1RemoveFromHash(pPage);
@@ -33008,6 +33982,7 @@
 */
 static void pcache1Destroy(sqlite3_pcache *p){
   PCache1 *pCache = (PCache1 *)p;
+  assert( pCache->bPurgeable || (pCache->nMax==0 && pCache->nMin==0) );
   pcache1EnterMutex();
   pcache1TruncateUnsafe(pCache, 0);
   pcache1.nMaxPage -= pCache->nMax;
@@ -33055,8 +34030,8 @@
   if( pcache1.pStart==0 ){
     PgHdr1 *p;
     pcache1EnterMutex();
-    while( (nReq<0 || nFree<nReq) && (p=pcache1.pLruTail) ){
-      nFree += sqlite3MallocSize(PGHDR1_TO_PAGE(p));
+    while( (nReq<0 || nFree<nReq) && ((p=pcache1.pLruTail)!=0) ){
+      nFree += pcache1MemSize(PGHDR1_TO_PAGE(p));
       pcache1PinPage(p);
       pcache1RemoveFromHash(p);
       pcache1FreePage(p);
@@ -33565,7 +34540,7 @@
 # define sqlite3WalBeginReadTransaction(y,z)   0
 # define sqlite3WalEndReadTransaction(z)
 # define sqlite3WalRead(v,w,x,y,z)             0
-# define sqlite3WalDbsize(y,z)
+# define sqlite3WalDbsize(y)                   0
 # define sqlite3WalBeginWriteTransaction(y)    0
 # define sqlite3WalEndWriteTransaction(x)      0
 # define sqlite3WalUndo(x,y,z)                 0
@@ -33601,9 +34576,8 @@
 /* Read a page from the write-ahead log, if it is present. */
 SQLITE_PRIVATE int sqlite3WalRead(Wal *pWal, Pgno pgno, int *pInWal, int nOut, u8 *pOut);
 
-/* Return the size of the database as it existed at the beginning
-** of the snapshot */
-SQLITE_PRIVATE void sqlite3WalDbsize(Wal *pWal, Pgno *pPgno);
+/* If the WAL is not empty, return the size of the database. */
+SQLITE_PRIVATE Pgno sqlite3WalDbsize(Wal *pWal);
 
 /* Obtain or release the WRITER lock. */
 SQLITE_PRIVATE int sqlite3WalBeginWriteTransaction(Wal *pWal);
@@ -33649,8 +34623,12 @@
 /************** End of wal.h *************************************************/
 /************** Continuing where we left off in pager.c **********************/
 
-/*
-******************** NOTES ON THE DESIGN OF THE PAGER ************************
+
+/******************* NOTES ON THE DESIGN OF THE PAGER ************************
+**
+** This comment block describes invariants that hold when using a rollback
+** journal.  These invariants do not apply for journal_mode=WAL,
+** journal_mode=MEMORY, or journal_mode=OFF.
 **
 ** Within this comment block, a page is deemed to have been synced
 ** automatically as soon as it is written when PRAGMA synchronous=OFF.
@@ -33684,7 +34662,7 @@
 **     transaction.
 ** 
 ** (3) Writes to the database file are an integer multiple of the page size
-**     in length and are aligned to a page boundary.
+**     in length and are aligned on a page boundary.
 ** 
 ** (4) Reads from the database file are either aligned on a page boundary and
 **     an integer multiple of the page size in length or are taken from the
@@ -33715,7 +34693,8 @@
 ** 
 ** (9) Whenever the database file is modified, at least one bit in the range
 **     of bytes from 24 through 39 inclusive will be changed prior to releasing
-**     the EXCLUSIVE lock.
+**     the EXCLUSIVE lock, thus signaling other connections on the same
+**     database to flush their caches.
 **
 ** (10) The pattern of bits in bytes 24 through 39 shall not repeat in less
 **      than one billion transactions.
@@ -33728,7 +34707,8 @@
 **
 ** (13) A SHARED lock is held on the database file while reading any
 **      content out of the database file.
-*/
+**
+******************************************************************************/
 
 /*
 ** Macros for troubleshooting.  Normally turned off
@@ -33753,58 +34733,279 @@
 #define FILEHANDLEID(fd) ((int)fd)
 
 /*
-** The page cache as a whole is always in one of the following
-** states:
+** The Pager.eState variable stores the current 'state' of a pager. A
+** pager may be in any one of the seven states shown in the following
+** state diagram.
 **
-**   PAGER_UNLOCK        The page cache is not currently reading or 
-**                       writing the database file.  There is no
-**                       data held in memory.  This is the initial
-**                       state.
+**                            OPEN <------+------+
+**                              |         |      |
+**                              V         |      |
+**               +---------> READER-------+      |
+**               |              |                |
+**               |              V                |
+**               |<-------WRITER_LOCKED------> ERROR
+**               |              |                ^  
+**               |              V                |
+**               |<------WRITER_CACHEMOD-------->|
+**               |              |                |
+**               |              V                |
+**               |<-------WRITER_DBMOD---------->|
+**               |              |                |
+**               |              V                |
+**               +<------WRITER_FINISHED-------->+
 **
-**   PAGER_SHARED        The page cache is reading the database.
-**                       Writing is not permitted.  There can be
-**                       multiple readers accessing the same database
-**                       file at the same time.
 **
-**   PAGER_RESERVED      This process has reserved the database for writing
-**                       but has not yet made any changes.  Only one process
-**                       at a time can reserve the database.  The original
-**                       database file has not been modified so other
-**                       processes may still be reading the on-disk
-**                       database file.
+** List of state transitions and the C [function] that performs each:
+** 
+**   OPEN              -> READER              [sqlite3PagerSharedLock]
+**   READER            -> OPEN                [pager_unlock]
 **
-**   PAGER_EXCLUSIVE     The page cache is writing the database.
-**                       Access is exclusive.  No other processes or
-**                       threads can be reading or writing while one
-**                       process is writing.
+**   READER            -> WRITER_LOCKED       [sqlite3PagerBegin]
+**   WRITER_LOCKED     -> WRITER_CACHEMOD     [pager_open_journal]
+**   WRITER_CACHEMOD   -> WRITER_DBMOD        [syncJournal]
+**   WRITER_DBMOD      -> WRITER_FINISHED     [sqlite3PagerCommitPhaseOne]
+**   WRITER_***        -> READER              [pager_end_transaction]
 **
-**   PAGER_SYNCED        The pager moves to this state from PAGER_EXCLUSIVE
-**                       after all dirty pages have been written to the
-**                       database file and the file has been synced to
-**                       disk. All that remains to do is to remove or
-**                       truncate the journal file and the transaction 
-**                       will be committed.
+**   WRITER_***        -> ERROR               [pager_error]
+**   ERROR             -> OPEN                [pager_unlock]
+** 
 **
-** The page cache comes up in PAGER_UNLOCK.  The first time a
-** sqlite3PagerGet() occurs, the state transitions to PAGER_SHARED.
-** After all pages have been released using sqlite_page_unref(),
-** the state transitions back to PAGER_UNLOCK.  The first time
-** that sqlite3PagerWrite() is called, the state transitions to
-** PAGER_RESERVED.  (Note that sqlite3PagerWrite() can only be
-** called on an outstanding page which means that the pager must
-** be in PAGER_SHARED before it transitions to PAGER_RESERVED.)
-** PAGER_RESERVED means that there is an open rollback journal.
-** The transition to PAGER_EXCLUSIVE occurs before any changes
-** are made to the database file, though writes to the rollback
-** journal occurs with just PAGER_RESERVED.  After an sqlite3PagerRollback()
-** or sqlite3PagerCommitPhaseTwo(), the state can go back to PAGER_SHARED,
-** or it can stay at PAGER_EXCLUSIVE if we are in exclusive access mode.
+**  OPEN:
+**
+**    The pager starts up in this state. Nothing is guaranteed in this
+**    state - the file may or may not be locked and the database size is
+**    unknown. The database may not be read or written.
+**
+**    * No read or write transaction is active.
+**    * Any lock, or no lock at all, may be held on the database file.
+**    * The dbSize, dbOrigSize and dbFileSize variables may not be trusted.
+**
+**  READER:
+**
+**    In this state all the requirements for reading the database in 
+**    rollback (non-WAL) mode are met. Unless the pager is (or recently
+**    was) in exclusive-locking mode, a user-level read transaction is 
+**    open. The database size is known in this state.
+**
+**    A connection running with locking_mode=normal enters this state when
+**    it opens a read-transaction on the database and returns to state
+**    OPEN after the read-transaction is completed. However a connection
+**    running in locking_mode=exclusive (including temp databases) remains in
+**    this state even after the read-transaction is closed. The only way
+**    a locking_mode=exclusive connection can transition from READER to OPEN
+**    is via the ERROR state (see below).
+** 
+**    * A read transaction may be active (but a write-transaction cannot).
+**    * A SHARED or greater lock is held on the database file.
+**    * The dbSize variable may be trusted (even if a user-level read 
+**      transaction is not active). The dbOrigSize and dbFileSize variables
+**      may not be trusted at this point.
+**    * If the database is a WAL database, then the WAL connection is open.
+**    * Even if a read-transaction is not open, it is guaranteed that 
+**      there is no hot-journal in the file-system.
+**
+**  WRITER_LOCKED:
+**
+**    The pager moves to this state from READER when a write-transaction
+**    is first opened on the database. In WRITER_LOCKED state, all locks 
+**    required to start a write-transaction are held, but no actual 
+**    modifications to the cache or database have taken place.
+**
+**    In rollback mode, a RESERVED or (if the transaction was opened with 
+**    BEGIN EXCLUSIVE) EXCLUSIVE lock is obtained on the database file when
+**    moving to this state, but the journal file is not written to or opened 
+**    to in this state. If the transaction is committed or rolled back while 
+**    in WRITER_LOCKED state, all that is required is to unlock the database 
+**    file.
+**
+**    IN WAL mode, WalBeginWriteTransaction() is called to lock the log file.
+**    If the connection is running with locking_mode=exclusive, an attempt
+**    is made to obtain an EXCLUSIVE lock on the database file.
+**
+**    * A write transaction is active.
+**    * If the connection is open in rollback-mode, a RESERVED or greater 
+**      lock is held on the database file.
+**    * If the connection is open in WAL-mode, a WAL write transaction
+**      is open (i.e. sqlite3WalBeginWriteTransaction() has been successfully
+**      called).
+**    * The dbSize, dbOrigSize and dbFileSize variables are all valid.
+**    * The contents of the pager cache have not been modified.
+**    * The journal file may or may not be open.
+**    * Nothing (not even the first header) has been written to the journal.
+**
+**  WRITER_CACHEMOD:
+**
+**    A pager moves from WRITER_LOCKED state to this state when a page is
+**    first modified by the upper layer. In rollback mode the journal file
+**    is opened (if it is not already open) and a header written to the
+**    start of it. The database file on disk has not been modified.
+**
+**    * A write transaction is active.
+**    * A RESERVED or greater lock is held on the database file.
+**    * The journal file is open and the first header has been written 
+**      to it, but the header has not been synced to disk.
+**    * The contents of the page cache have been modified.
+**
+**  WRITER_DBMOD:
+**
+**    The pager transitions from WRITER_CACHEMOD into WRITER_DBMOD state
+**    when it modifies the contents of the database file. WAL connections
+**    never enter this state (since they do not modify the database file,
+**    just the log file).
+**
+**    * A write transaction is active.
+**    * An EXCLUSIVE or greater lock is held on the database file.
+**    * The journal file is open and the first header has been written 
+**      and synced to disk.
+**    * The contents of the page cache have been modified (and possibly
+**      written to disk).
+**
+**  WRITER_FINISHED:
+**
+**    It is not possible for a WAL connection to enter this state.
+**
+**    A rollback-mode pager changes to WRITER_FINISHED state from WRITER_DBMOD
+**    state after the entire transaction has been successfully written into the
+**    database file. In this state the transaction may be committed simply
+**    by finalizing the journal file. Once in WRITER_FINISHED state, it is 
+**    not possible to modify the database further. At this point, the upper 
+**    layer must either commit or rollback the transaction.
+**
+**    * A write transaction is active.
+**    * An EXCLUSIVE or greater lock is held on the database file.
+**    * All writing and syncing of journal and database data has finished.
+**      If no error occured, all that remains is to finalize the journal to
+**      commit the transaction. If an error did occur, the caller will need
+**      to rollback the transaction. 
+**
+**  ERROR:
+**
+**    The ERROR state is entered when an IO or disk-full error (including
+**    SQLITE_IOERR_NOMEM) occurs at a point in the code that makes it 
+**    difficult to be sure that the in-memory pager state (cache contents, 
+**    db size etc.) are consistent with the contents of the file-system.
+**
+**    Temporary pager files may enter the ERROR state, but in-memory pagers
+**    cannot.
+**
+**    For example, if an IO error occurs while performing a rollback, 
+**    the contents of the page-cache may be left in an inconsistent state.
+**    At this point it would be dangerous to change back to READER state
+**    (as usually happens after a rollback). Any subsequent readers might
+**    report database corruption (due to the inconsistent cache), and if
+**    they upgrade to writers, they may inadvertently corrupt the database
+**    file. To avoid this hazard, the pager switches into the ERROR state
+**    instead of READER following such an error.
+**
+**    Once it has entered the ERROR state, any attempt to use the pager
+**    to read or write data returns an error. Eventually, once all 
+**    outstanding transactions have been abandoned, the pager is able to
+**    transition back to OPEN state, discarding the contents of the 
+**    page-cache and any other in-memory state at the same time. Everything
+**    is reloaded from disk (and, if necessary, hot-journal rollback peformed)
+**    when a read-transaction is next opened on the pager (transitioning
+**    the pager into READER state). At that point the system has recovered 
+**    from the error.
+**
+**    Specifically, the pager jumps into the ERROR state if:
+**
+**      1. An error occurs while attempting a rollback. This happens in
+**         function sqlite3PagerRollback().
+**
+**      2. An error occurs while attempting to finalize a journal file
+**         following a commit in function sqlite3PagerCommitPhaseTwo().
+**
+**      3. An error occurs while attempting to write to the journal or
+**         database file in function pagerStress() in order to free up
+**         memory.
+**
+**    In other cases, the error is returned to the b-tree layer. The b-tree
+**    layer then attempts a rollback operation. If the error condition 
+**    persists, the pager enters the ERROR state via condition (1) above.
+**
+**    Condition (3) is necessary because it can be triggered by a read-only
+**    statement executed within a transaction. In this case, if the error
+**    code were simply returned to the user, the b-tree layer would not
+**    automatically attempt a rollback, as it assumes that an error in a
+**    read-only statement cannot leave the pager in an internally inconsistent 
+**    state.
+**
+**    * The Pager.errCode variable is set to something other than SQLITE_OK.
+**    * There are one or more outstanding references to pages (after the
+**      last reference is dropped the pager should move back to OPEN state).
+**    * The pager is not an in-memory pager.
+**    
+**
+** Notes:
+**
+**   * A pager is never in WRITER_DBMOD or WRITER_FINISHED state if the
+**     connection is open in WAL mode. A WAL connection is always in one
+**     of the first four states.
+**
+**   * Normally, a connection open in exclusive mode is never in PAGER_OPEN
+**     state. There are two exceptions: immediately after exclusive-mode has
+**     been turned on (and before any read or write transactions are 
+**     executed), and when the pager is leaving the "error state".
+**
+**   * See also: assert_pager_state().
 */
-#define PAGER_UNLOCK      0
-#define PAGER_SHARED      1   /* same as SHARED_LOCK */
-#define PAGER_RESERVED    2   /* same as RESERVED_LOCK */
-#define PAGER_EXCLUSIVE   4   /* same as EXCLUSIVE_LOCK */
-#define PAGER_SYNCED      5
+#define PAGER_OPEN                  0
+#define PAGER_READER                1
+#define PAGER_WRITER_LOCKED         2
+#define PAGER_WRITER_CACHEMOD       3
+#define PAGER_WRITER_DBMOD          4
+#define PAGER_WRITER_FINISHED       5
+#define PAGER_ERROR                 6
+
+/*
+** The Pager.eLock variable is almost always set to one of the 
+** following locking-states, according to the lock currently held on
+** the database file: NO_LOCK, SHARED_LOCK, RESERVED_LOCK or EXCLUSIVE_LOCK.
+** This variable is kept up to date as locks are taken and released by
+** the pagerLockDb() and pagerUnlockDb() wrappers.
+**
+** If the VFS xLock() or xUnlock() returns an error other than SQLITE_BUSY
+** (i.e. one of the SQLITE_IOERR subtypes), it is not clear whether or not
+** the operation was successful. In these circumstances pagerLockDb() and
+** pagerUnlockDb() take a conservative approach - eLock is always updated
+** when unlocking the file, and only updated when locking the file if the
+** VFS call is successful. This way, the Pager.eLock variable may be set
+** to a less exclusive (lower) value than the lock that is actually held
+** at the system level, but it is never set to a more exclusive value.
+**
+** This is usually safe. If an xUnlock fails or appears to fail, there may 
+** be a few redundant xLock() calls or a lock may be held for longer than
+** required, but nothing really goes wrong.
+**
+** The exception is when the database file is unlocked as the pager moves
+** from ERROR to OPEN state. At this point there may be a hot-journal file 
+** in the file-system that needs to be rolled back (as part of a OPEN->SHARED
+** transition, by the same pager or any other). If the call to xUnlock()
+** fails at this point and the pager is left holding an EXCLUSIVE lock, this
+** can confuse the call to xCheckReservedLock() call made later as part
+** of hot-journal detection.
+**
+** xCheckReservedLock() is defined as returning true "if there is a RESERVED 
+** lock held by this process or any others". So xCheckReservedLock may 
+** return true because the caller itself is holding an EXCLUSIVE lock (but
+** doesn't know it because of a previous error in xUnlock). If this happens
+** a hot-journal may be mistaken for a journal being created by an active
+** transaction in another process, causing SQLite to read from the database
+** without rolling it back.
+**
+** To work around this, if a call to xUnlock() fails when unlocking the
+** database in the ERROR state, Pager.eLock is set to UNKNOWN_LOCK. It
+** is only changed back to a real locking state after a successful call
+** to xLock(EXCLUSIVE). Also, the code to do the OPEN->SHARED state transition
+** omits the check for a hot-journal if Pager.eLock is set to UNKNOWN_LOCK 
+** lock. Instead, it assumes a hot-journal exists and obtains an EXCLUSIVE
+** lock on the database file before attempting to roll it back. See function
+** PagerSharedLock() for more detail.
+**
+** Pager.eLock may only be set to UNKNOWN_LOCK when the pager is in 
+** PAGER_OPEN state.
+*/
+#define UNKNOWN_LOCK                (EXCLUSIVE_LOCK+1)
 
 /*
 ** A macro used for invoking the codec if there is one
@@ -33854,33 +35055,28 @@
 };
 
 /*
-** A open page cache is an instance of the following structure.
+** A open page cache is an instance of struct Pager. A description of
+** some of the more important member variables follows:
 **
-** errCode
+** eState
 **
-**   Pager.errCode may be set to SQLITE_IOERR, SQLITE_CORRUPT, or
-**   or SQLITE_FULL. Once one of the first three errors occurs, it persists
-**   and is returned as the result of every major pager API call.  The
-**   SQLITE_FULL return code is slightly different. It persists only until the
-**   next successful rollback is performed on the pager cache. Also,
-**   SQLITE_FULL does not affect the sqlite3PagerGet() and sqlite3PagerLookup()
-**   APIs, they may still be used successfully.
+**   The current 'state' of the pager object. See the comment and state
+**   diagram above for a description of the pager state.
 **
-** dbSizeValid, dbSize, dbOrigSize, dbFileSize
+** eLock
 **
-**   Managing the size of the database file in pages is a little complicated.
-**   The variable Pager.dbSize contains the number of pages that the database
-**   image currently contains. As the database image grows or shrinks this
-**   variable is updated. The variable Pager.dbFileSize contains the number
-**   of pages in the database file. This may be different from Pager.dbSize
-**   if some pages have been appended to the database image but not yet written
-**   out from the cache to the actual file on disk. Or if the image has been
-**   truncated by an incremental-vacuum operation. The Pager.dbOrigSize variable
-**   contains the number of pages in the database image when the current
-**   transaction was opened. The contents of all three of these variables is
-**   only guaranteed to be correct if the boolean Pager.dbSizeValid is true.
+**   For a real on-disk database, the current lock held on the database file -
+**   NO_LOCK, SHARED_LOCK, RESERVED_LOCK or EXCLUSIVE_LOCK.
 **
-**   TODO: Under what conditions is dbSizeValid set? Cleared?
+**   For a temporary or in-memory database (neither of which require any
+**   locks), this variable is always set to EXCLUSIVE_LOCK. Since such
+**   databases always have Pager.exclusiveMode==1, this tricks the pager
+**   logic into thinking that it already has all the locks it will ever
+**   need (and no reason to release them).
+**
+**   In some (obscure) circumstances, this variable may also be set to
+**   UNKNOWN_LOCK. See the comment above the #define of UNKNOWN_LOCK for
+**   details.
 **
 ** changeCountDone
 **
@@ -33899,67 +35095,123 @@
 **   need only update the change-counter once, for the first transaction
 **   committed.
 **
-** dbModified
-**
-**   The dbModified flag is set whenever a database page is dirtied.
-**   It is cleared at the end of each transaction.
-**
-**   It is used when committing or otherwise ending a transaction. If
-**   the dbModified flag is clear then less work has to be done.
-**
-** journalStarted
-**
-**   This flag is set whenever the the main journal is opened and
-**   initialized
-**
-**   The point of this flag is that it must be set after the 
-**   first journal header in a journal file has been synced to disk.
-**   After this has happened, new pages appended to the database 
-**   do not need the PGHDR_NEED_SYNC flag set, as they do not need
-**   to wait for a journal sync before they can be written out to
-**   the database file (see function pager_write()).
-**   
 ** setMaster
 **
-**   This variable is used to ensure that the master journal file name
-**   (if any) is only written into the journal file once.
+**   When PagerCommitPhaseOne() is called to commit a transaction, it may
+**   (or may not) specify a master-journal name to be written into the 
+**   journal file before it is synced to disk.
 **
-**   When committing a transaction, the master journal file name (if any)
-**   may be written into the journal file while the pager is still in
-**   PAGER_RESERVED state (see CommitPhaseOne() for the action). It
-**   then attempts to upgrade to an exclusive lock. If this attempt
-**   fails, then SQLITE_BUSY may be returned to the user and the user
-**   may attempt to commit the transaction again later (calling
-**   CommitPhaseOne() again). This flag is used to ensure that the 
-**   master journal name is only written to the journal file the first
-**   time CommitPhaseOne() is called.
+**   Whether or not a journal file contains a master-journal pointer affects 
+**   the way in which the journal file is finalized after the transaction is 
+**   committed or rolled back when running in "journal_mode=PERSIST" mode.
+**   If a journal file does not contain a master-journal pointer, it is
+**   finalized by overwriting the first journal header with zeroes. If
+**   it does contain a master-journal pointer the journal file is finalized 
+**   by truncating it to zero bytes, just as if the connection were 
+**   running in "journal_mode=truncate" mode.
+**
+**   Journal files that contain master journal pointers cannot be finalized
+**   simply by overwriting the first journal-header with zeroes, as the
+**   master journal pointer could interfere with hot-journal rollback of any
+**   subsequently interrupted transaction that reuses the journal file.
+**
+**   The flag is cleared as soon as the journal file is finalized (either
+**   by PagerCommitPhaseTwo or PagerRollback). If an IO error prevents the
+**   journal file from being successfully finalized, the setMaster flag
+**   is cleared anyway (and the pager will move to ERROR state).
 **
 ** doNotSpill, doNotSyncSpill
 **
-**   When enabled, cache spills are prohibited.  The doNotSpill variable
-**   inhibits all cache spill and doNotSyncSpill inhibits those spills that
-**   would require a journal sync.  The doNotSyncSpill is set and cleared 
-**   by sqlite3PagerWrite() in order to prevent a journal sync from happening 
-**   in between the journalling of two pages on the same sector.  The
-**   doNotSpill value set to prevent pagerStress() from trying to use
-**   the journal during a rollback.
+**   These two boolean variables control the behaviour of cache-spills
+**   (calls made by the pcache module to the pagerStress() routine to
+**   write cached data to the file-system in order to free up memory).
 **
-** needSync
-**
-**   TODO: It might be easier to set this variable in writeJournalHdr()
-**   and writeMasterJournal() only. Change its meaning to "unsynced data
-**   has been written to the journal".
+**   When doNotSpill is non-zero, writing to the database from pagerStress()
+**   is disabled altogether. This is done in a very obscure case that
+**   comes up during savepoint rollback that requires the pcache module
+**   to allocate a new page to prevent the journal file from being written
+**   while it is being traversed by code in pager_playback().
+** 
+**   If doNotSyncSpill is non-zero, writing to the database from pagerStress()
+**   is permitted, but syncing the journal file is not. This flag is set
+**   by sqlite3PagerWrite() when the file-system sector-size is larger than
+**   the database page-size in order to prevent a journal sync from happening 
+**   in between the journalling of two pages on the same sector. 
 **
 ** subjInMemory
 **
 **   This is a boolean variable. If true, then any required sub-journal
 **   is opened as an in-memory journal file. If false, then in-memory
 **   sub-journals are only used for in-memory pager files.
+**
+**   This variable is updated by the upper layer each time a new 
+**   write-transaction is opened.
+**
+** dbSize, dbOrigSize, dbFileSize
+**
+**   Variable dbSize is set to the number of pages in the database file.
+**   It is valid in PAGER_READER and higher states (all states except for
+**   OPEN and ERROR). 
+**
+**   dbSize is set based on the size of the database file, which may be 
+**   larger than the size of the database (the value stored at offset
+**   28 of the database header by the btree). If the size of the file
+**   is not an integer multiple of the page-size, the value stored in
+**   dbSize is rounded down (i.e. a 5KB file with 2K page-size has dbSize==2).
+**   Except, any file that is greater than 0 bytes in size is considered
+**   to have at least one page. (i.e. a 1KB file with 2K page-size leads
+**   to dbSize==1).
+**
+**   During a write-transaction, if pages with page-numbers greater than
+**   dbSize are modified in the cache, dbSize is updated accordingly.
+**   Similarly, if the database is truncated using PagerTruncateImage(), 
+**   dbSize is updated.
+**
+**   Variables dbOrigSize and dbFileSize are valid in states 
+**   PAGER_WRITER_LOCKED and higher. dbOrigSize is a copy of the dbSize
+**   variable at the start of the transaction. It is used during rollback,
+**   and to determine whether or not pages need to be journalled before
+**   being modified.
+**
+**   Throughout a write-transaction, dbFileSize contains the size of
+**   the file on disk in pages. It is set to a copy of dbSize when the
+**   write-transaction is first opened, and updated when VFS calls are made
+**   to write or truncate the database file on disk. 
+**
+**   The only reason the dbFileSize variable is required is to suppress 
+**   unnecessary calls to xTruncate() after committing a transaction. If, 
+**   when a transaction is committed, the dbFileSize variable indicates 
+**   that the database file is larger than the database image (Pager.dbSize), 
+**   pager_truncate() is called. The pager_truncate() call uses xFilesize()
+**   to measure the database file on disk, and then truncates it if required.
+**   dbFileSize is not used when rolling back a transaction. In this case
+**   pager_truncate() is called unconditionally (which means there may be
+**   a call to xFilesize() that is not strictly required). In either case,
+**   pager_truncate() may cause the file to become smaller or larger.
+**
+** dbHintSize
+**
+**   The dbHintSize variable is used to limit the number of calls made to
+**   the VFS xFileControl(FCNTL_SIZE_HINT) method. 
+**
+**   dbHintSize is set to a copy of the dbSize variable when a
+**   write-transaction is opened (at the same time as dbFileSize and
+**   dbOrigSize). If the xFileControl(FCNTL_SIZE_HINT) method is called,
+**   dbHintSize is increased to the number of pages that correspond to the
+**   size-hint passed to the method call. See pager_write_pagelist() for 
+**   details.
+**
+** errCode
+**
+**   The Pager.errCode variable is only ever used in PAGER_ERROR state. It
+**   is set to zero in all other states. In PAGER_ERROR state, Pager.errCode 
+**   is always set to SQLITE_FULL, SQLITE_IOERR or one of the SQLITE_IOERR_XXX 
+**   sub-codes.
 */
 struct Pager {
   sqlite3_vfs *pVfs;          /* OS functions to use for IO */
   u8 exclusiveMode;           /* Boolean. True if locking_mode==EXCLUSIVE */
-  u8 journalMode;             /* On of the PAGER_JOURNALMODE_* values */
+  u8 journalMode;             /* One of the PAGER_JOURNALMODE_* values */
   u8 useJournal;              /* Use a rollback journal on this file */
   u8 noReadlock;              /* Do not bother to obtain readlocks */
   u8 noSync;                  /* Do not sync the journal if true */
@@ -33969,30 +35221,26 @@
   u8 readOnly;                /* True for a read-only database */
   u8 memDb;                   /* True to inhibit all file I/O */
 
-  /* The following block contains those class members that are dynamically
-  ** modified during normal operations. The other variables in this structure
-  ** are either constant throughout the lifetime of the pager, or else
-  ** used to store configuration parameters that affect the way the pager 
-  ** operates.
-  **
-  ** The 'state' variable is described in more detail along with the
-  ** descriptions of the values it may take - PAGER_UNLOCK etc. Many of the
-  ** other variables in this block are described in the comment directly 
-  ** above this class definition.
+  /**************************************************************************
+  ** The following block contains those class members that change during
+  ** routine opertion.  Class members not in this block are either fixed
+  ** when the pager is first created or else only change when there is a
+  ** significant mode change (such as changing the page_size, locking_mode,
+  ** or the journal_mode).  From another view, these class members describe
+  ** the "state" of the pager, while other class members describe the
+  ** "configuration" of the pager.
   */
-  u8 state;                   /* PAGER_UNLOCK, _SHARED, _RESERVED, etc. */
-  u8 dbModified;              /* True if there are any changes to the Db */
-  u8 needSync;                /* True if an fsync() is needed on the journal */
-  u8 journalStarted;          /* True if header of journal is synced */
+  u8 eState;                  /* Pager state (OPEN, READER, WRITER_LOCKED..) */
+  u8 eLock;                   /* Current lock held on database file */
   u8 changeCountDone;         /* Set after incrementing the change-counter */
   u8 setMaster;               /* True if a m-j name has been written to jrnl */
   u8 doNotSpill;              /* Do not spill the cache when non-zero */
   u8 doNotSyncSpill;          /* Do not do a spill that requires jrnl sync */
-  u8 dbSizeValid;             /* Set when dbSize is correct */
   u8 subjInMemory;            /* True to use in-memory sub-journals */
   Pgno dbSize;                /* Number of pages in the database */
   Pgno dbOrigSize;            /* dbSize before the current transaction */
   Pgno dbFileSize;            /* Number of pages in the database file */
+  Pgno dbHintSize;            /* Value passed to FCNTL_SIZE_HINT call */
   int errCode;                /* One of several kinds of errors */
   int nRec;                   /* Pages journalled since last j-header written */
   u32 cksumInit;              /* Quasi-random value added to every checksum */
@@ -34003,17 +35251,21 @@
   sqlite3_file *sjfd;         /* File descriptor for sub-journal */
   i64 journalOff;             /* Current write offset in the journal file */
   i64 journalHdr;             /* Byte offset to previous journal header */
-  i64 journalSizeLimit;       /* Size limit for persistent journal files */
+  sqlite3_backup *pBackup;    /* Pointer to list of ongoing backup processes */
   PagerSavepoint *aSavepoint; /* Array of active savepoints */
   int nSavepoint;             /* Number of elements in aSavepoint[] */
   char dbFileVers[16];        /* Changes whenever database file changes */
-  u32 sectorSize;             /* Assumed sector size during rollback */
+  /*
+  ** End of the routinely-changing class members
+  ***************************************************************************/
 
   u16 nExtra;                 /* Add this many bytes to each in-memory page */
   i16 nReserve;               /* Number of unused bytes at end of each page */
   u32 vfsFlags;               /* Flags for sqlite3_vfs.xOpen() */
+  u32 sectorSize;             /* Assumed sector size during rollback */
   int pageSize;               /* Number of bytes in a page */
   Pgno mxPgno;                /* Maximum allowed size of the database */
+  i64 journalSizeLimit;       /* Size limit for persistent journal files */
   char *zFilename;            /* Name of the database file */
   char *zJournal;             /* Name of the journal file */
   int (*xBusyHandler)(void*); /* Function to call when busy */
@@ -34031,7 +35283,6 @@
 #endif
   char *pTmpSpace;            /* Pager.pageSize bytes of space for tmp use */
   PCache *pPCache;            /* Pointer to page cache object */
-  sqlite3_backup *pBackup;    /* Pointer to list of ongoing backup processes */
 #ifndef SQLITE_OMIT_WAL
   Wal *pWal;                  /* Write-ahead log used by "journal_mode=wal" */
   char *zWal;                 /* File name for write-ahead log */
@@ -34110,22 +35361,221 @@
 */
 #define PAGER_MAX_PGNO 2147483647
 
+/*
+** The argument to this macro is a file descriptor (type sqlite3_file*).
+** Return 0 if it is not open, or non-zero (but not 1) if it is.
+**
+** This is so that expressions can be written as:
+**
+**   if( isOpen(pPager->jfd) ){ ...
+**
+** instead of
+**
+**   if( pPager->jfd->pMethods ){ ...
+*/
+#define isOpen(pFd) ((pFd)->pMethods)
+
+/*
+** Return true if this pager uses a write-ahead log instead of the usual
+** rollback journal. Otherwise false.
+*/
+#ifndef SQLITE_OMIT_WAL
+static int pagerUseWal(Pager *pPager){
+  return (pPager->pWal!=0);
+}
+#else
+# define pagerUseWal(x) 0
+# define pagerRollbackWal(x) 0
+# define pagerWalFrames(v,w,x,y,z) 0
+# define pagerOpenWalIfPresent(z) SQLITE_OK
+# define pagerBeginReadTransaction(z) SQLITE_OK
+#endif
+
 #ifndef NDEBUG 
 /*
 ** Usage:
 **
 **   assert( assert_pager_state(pPager) );
+**
+** This function runs many asserts to try to find inconsistencies in
+** the internal state of the Pager object.
 */
-static int assert_pager_state(Pager *pPager){
+static int assert_pager_state(Pager *p){
+  Pager *pPager = p;
 
-  /* A temp-file is always in PAGER_EXCLUSIVE or PAGER_SYNCED state. */
-  assert( pPager->tempFile==0 || pPager->state>=PAGER_EXCLUSIVE );
+  /* State must be valid. */
+  assert( p->eState==PAGER_OPEN
+       || p->eState==PAGER_READER
+       || p->eState==PAGER_WRITER_LOCKED
+       || p->eState==PAGER_WRITER_CACHEMOD
+       || p->eState==PAGER_WRITER_DBMOD
+       || p->eState==PAGER_WRITER_FINISHED
+       || p->eState==PAGER_ERROR
+  );
 
-  /* The changeCountDone flag is always set for temp-files */
-  assert( pPager->tempFile==0 || pPager->changeCountDone );
+  /* Regardless of the current state, a temp-file connection always behaves
+  ** as if it has an exclusive lock on the database file. It never updates
+  ** the change-counter field, so the changeCountDone flag is always set.
+  */
+  assert( p->tempFile==0 || p->eLock==EXCLUSIVE_LOCK );
+  assert( p->tempFile==0 || pPager->changeCountDone );
+
+  /* If the useJournal flag is clear, the journal-mode must be "OFF". 
+  ** And if the journal-mode is "OFF", the journal file must not be open.
+  */
+  assert( p->journalMode==PAGER_JOURNALMODE_OFF || p->useJournal );
+  assert( p->journalMode!=PAGER_JOURNALMODE_OFF || !isOpen(p->jfd) );
+
+  /* Check that MEMDB implies noSync. And an in-memory journal. Since 
+  ** this means an in-memory pager performs no IO at all, it cannot encounter 
+  ** either SQLITE_IOERR or SQLITE_FULL during rollback or while finalizing 
+  ** a journal file. (although the in-memory journal implementation may 
+  ** return SQLITE_IOERR_NOMEM while the journal file is being written). It 
+  ** is therefore not possible for an in-memory pager to enter the ERROR 
+  ** state.
+  */
+  if( MEMDB ){
+    assert( p->noSync );
+    assert( p->journalMode==PAGER_JOURNALMODE_OFF 
+         || p->journalMode==PAGER_JOURNALMODE_MEMORY 
+    );
+    assert( p->eState!=PAGER_ERROR && p->eState!=PAGER_OPEN );
+    assert( pagerUseWal(p)==0 );
+  }
+
+  /* If changeCountDone is set, a RESERVED lock or greater must be held
+  ** on the file.
+  */
+  assert( pPager->changeCountDone==0 || pPager->eLock>=RESERVED_LOCK );
+  assert( p->eLock!=PENDING_LOCK );
+
+  switch( p->eState ){
+    case PAGER_OPEN:
+      assert( !MEMDB );
+      assert( pPager->errCode==SQLITE_OK );
+      assert( sqlite3PcacheRefCount(pPager->pPCache)==0 || pPager->tempFile );
+      break;
+
+    case PAGER_READER:
+      assert( pPager->errCode==SQLITE_OK );
+      assert( p->eLock!=UNKNOWN_LOCK );
+      assert( p->eLock>=SHARED_LOCK || p->noReadlock );
+      break;
+
+    case PAGER_WRITER_LOCKED:
+      assert( p->eLock!=UNKNOWN_LOCK );
+      assert( pPager->errCode==SQLITE_OK );
+      if( !pagerUseWal(pPager) ){
+        assert( p->eLock>=RESERVED_LOCK );
+      }
+      assert( pPager->dbSize==pPager->dbOrigSize );
+      assert( pPager->dbOrigSize==pPager->dbFileSize );
+      assert( pPager->dbOrigSize==pPager->dbHintSize );
+      assert( pPager->setMaster==0 );
+      break;
+
+    case PAGER_WRITER_CACHEMOD:
+      assert( p->eLock!=UNKNOWN_LOCK );
+      assert( pPager->errCode==SQLITE_OK );
+      if( !pagerUseWal(pPager) ){
+        /* It is possible that if journal_mode=wal here that neither the
+        ** journal file nor the WAL file are open. This happens during
+        ** a rollback transaction that switches from journal_mode=off
+        ** to journal_mode=wal.
+        */
+        assert( p->eLock>=RESERVED_LOCK );
+        assert( isOpen(p->jfd) 
+             || p->journalMode==PAGER_JOURNALMODE_OFF 
+             || p->journalMode==PAGER_JOURNALMODE_WAL 
+        );
+      }
+      assert( pPager->dbOrigSize==pPager->dbFileSize );
+      assert( pPager->dbOrigSize==pPager->dbHintSize );
+      break;
+
+    case PAGER_WRITER_DBMOD:
+      assert( p->eLock==EXCLUSIVE_LOCK );
+      assert( pPager->errCode==SQLITE_OK );
+      assert( !pagerUseWal(pPager) );
+      assert( p->eLock>=EXCLUSIVE_LOCK );
+      assert( isOpen(p->jfd) 
+           || p->journalMode==PAGER_JOURNALMODE_OFF 
+           || p->journalMode==PAGER_JOURNALMODE_WAL 
+      );
+      assert( pPager->dbOrigSize<=pPager->dbHintSize );
+      break;
+
+    case PAGER_WRITER_FINISHED:
+      assert( p->eLock==EXCLUSIVE_LOCK );
+      assert( pPager->errCode==SQLITE_OK );
+      assert( !pagerUseWal(pPager) );
+      assert( isOpen(p->jfd) 
+           || p->journalMode==PAGER_JOURNALMODE_OFF 
+           || p->journalMode==PAGER_JOURNALMODE_WAL 
+      );
+      break;
+
+    case PAGER_ERROR:
+      /* There must be at least one outstanding reference to the pager if
+      ** in ERROR state. Otherwise the pager should have already dropped
+      ** back to OPEN state.
+      */
+      assert( pPager->errCode!=SQLITE_OK );
+      assert( sqlite3PcacheRefCount(pPager->pPCache)>0 );
+      break;
+  }
 
   return 1;
 }
+
+/*
+** Return a pointer to a human readable string in a static buffer
+** containing the state of the Pager object passed as an argument. This
+** is intended to be used within debuggers. For example, as an alternative
+** to "print *pPager" in gdb:
+**
+** (gdb) printf "%s", print_pager_state(pPager)
+*/
+static char *print_pager_state(Pager *p){
+  static char zRet[1024];
+
+  sqlite3_snprintf(1024, zRet,
+      "Filename:      %s\n"
+      "State:         %s errCode=%d\n"
+      "Lock:          %s\n"
+      "Locking mode:  locking_mode=%s\n"
+      "Journal mode:  journal_mode=%s\n"
+      "Backing store: tempFile=%d memDb=%d useJournal=%d\n"
+      "Journal:       journalOff=%lld journalHdr=%lld\n"
+      "Size:          dbsize=%d dbOrigSize=%d dbFileSize=%d\n"
+      , p->zFilename
+      , p->eState==PAGER_OPEN            ? "OPEN" :
+        p->eState==PAGER_READER          ? "READER" :
+        p->eState==PAGER_WRITER_LOCKED   ? "WRITER_LOCKED" :
+        p->eState==PAGER_WRITER_CACHEMOD ? "WRITER_CACHEMOD" :
+        p->eState==PAGER_WRITER_DBMOD    ? "WRITER_DBMOD" :
+        p->eState==PAGER_WRITER_FINISHED ? "WRITER_FINISHED" :
+        p->eState==PAGER_ERROR           ? "ERROR" : "?error?"
+      , (int)p->errCode
+      , p->eLock==NO_LOCK         ? "NO_LOCK" :
+        p->eLock==RESERVED_LOCK   ? "RESERVED" :
+        p->eLock==EXCLUSIVE_LOCK  ? "EXCLUSIVE" :
+        p->eLock==SHARED_LOCK     ? "SHARED" :
+        p->eLock==UNKNOWN_LOCK    ? "UNKNOWN" : "?error?"
+      , p->exclusiveMode ? "exclusive" : "normal"
+      , p->journalMode==PAGER_JOURNALMODE_MEMORY   ? "memory" :
+        p->journalMode==PAGER_JOURNALMODE_OFF      ? "off" :
+        p->journalMode==PAGER_JOURNALMODE_DELETE   ? "delete" :
+        p->journalMode==PAGER_JOURNALMODE_PERSIST  ? "persist" :
+        p->journalMode==PAGER_JOURNALMODE_TRUNCATE ? "truncate" :
+        p->journalMode==PAGER_JOURNALMODE_WAL      ? "wal" : "?error?"
+      , (int)p->tempFile, (int)p->memDb, (int)p->useJournal
+      , p->journalOff, p->journalHdr
+      , (int)p->dbSize, (int)p->dbOrigSize, (int)p->dbFileSize
+  );
+
+  return zRet;
+}
 #endif
 
 /*
@@ -34178,6 +35628,7 @@
 */
 #define put32bits(A,B)  sqlite3Put4byte((u8*)A,B)
 
+
 /*
 ** Write a 32-bit integer into the given file descriptor.  Return SQLITE_OK
 ** on success or an error code is something goes wrong.
@@ -34189,27 +35640,53 @@
 }
 
 /*
-** The argument to this macro is a file descriptor (type sqlite3_file*).
-** Return 0 if it is not open, or non-zero (but not 1) if it is.
+** Unlock the database file to level eLock, which must be either NO_LOCK
+** or SHARED_LOCK. Regardless of whether or not the call to xUnlock()
+** succeeds, set the Pager.eLock variable to match the (attempted) new lock.
 **
-** This is so that expressions can be written as:
-**
-**   if( isOpen(pPager->jfd) ){ ...
-**
-** instead of
-**
-**   if( pPager->jfd->pMethods ){ ...
+** Except, if Pager.eLock is set to UNKNOWN_LOCK when this function is
+** called, do not modify it. See the comment above the #define of 
+** UNKNOWN_LOCK for an explanation of this.
 */
-#define isOpen(pFd) ((pFd)->pMethods)
+static int pagerUnlockDb(Pager *pPager, int eLock){
+  int rc = SQLITE_OK;
+
+  assert( !pPager->exclusiveMode );
+  assert( eLock==NO_LOCK || eLock==SHARED_LOCK );
+  assert( eLock!=NO_LOCK || pagerUseWal(pPager)==0 );
+  if( isOpen(pPager->fd) ){
+    assert( pPager->eLock>=eLock );
+    rc = sqlite3OsUnlock(pPager->fd, eLock);
+    if( pPager->eLock!=UNKNOWN_LOCK ){
+      pPager->eLock = (u8)eLock;
+    }
+    IOTRACE(("UNLOCK %p %d\n", pPager, eLock))
+  }
+  return rc;
+}
 
 /*
-** If file pFd is open, call sqlite3OsUnlock() on it.
+** Lock the database file to level eLock, which must be either SHARED_LOCK,
+** RESERVED_LOCK or EXCLUSIVE_LOCK. If the caller is successful, set the
+** Pager.eLock variable to the new locking state. 
+**
+** Except, if Pager.eLock is set to UNKNOWN_LOCK when this function is 
+** called, do not modify it unless the new locking state is EXCLUSIVE_LOCK. 
+** See the comment above the #define of UNKNOWN_LOCK for an explanation 
+** of this.
 */
-static int osUnlock(sqlite3_file *pFd, int eLock){
-  if( !isOpen(pFd) ){
-    return SQLITE_OK;
+static int pagerLockDb(Pager *pPager, int eLock){
+  int rc = SQLITE_OK;
+
+  assert( eLock==SHARED_LOCK || eLock==RESERVED_LOCK || eLock==EXCLUSIVE_LOCK );
+  if( pPager->eLock<eLock || pPager->eLock==UNKNOWN_LOCK ){
+    rc = sqlite3OsLock(pPager->fd, eLock);
+    if( rc==SQLITE_OK && (pPager->eLock!=UNKNOWN_LOCK||eLock==EXCLUSIVE_LOCK) ){
+      pPager->eLock = (u8)eLock;
+      IOTRACE(("LOCK %p %d\n", pPager, eLock))
+    }
   }
-  return sqlite3OsUnlock(pFd, eLock);
+  return rc;
 }
 
 /*
@@ -34285,13 +35762,14 @@
 #define CHECK_PAGE(x) checkPage(x)
 static void checkPage(PgHdr *pPg){
   Pager *pPager = pPg->pPager;
-  assert( !pPg->pageHash || pPager->errCode
-      || (pPg->flags&PGHDR_DIRTY) || pPg->pageHash==pager_pagehash(pPg) );
+  assert( pPager->eState!=PAGER_ERROR );
+  assert( (pPg->flags&PGHDR_DIRTY) || pPg->pageHash==pager_pagehash(pPg) );
 }
 
 #else
 #define pager_datahash(X,Y)  0
 #define pager_pagehash(X)  0
+#define pager_set_pagehash(X)
 #define CHECK_PAGE(x)
 #endif  /* SQLITE_CHECK_PAGES */
 
@@ -34458,7 +35936,7 @@
 static int writeJournalHdr(Pager *pPager){
   int rc = SQLITE_OK;                 /* Return code */
   char *zHeader = pPager->pTmpSpace;  /* Temporary space used to build header */
-  u32 nHeader = pPager->pageSize;     /* Size of buffer pointed to by zHeader */
+  u32 nHeader = (u32)pPager->pageSize;/* Size of buffer pointed to by zHeader */
   u32 nWrite;                         /* Bytes of header sector written */
   int ii;                             /* Loop counter */
 
@@ -34501,7 +35979,7 @@
   **     that garbage data is never appended to the journal file.
   */
   assert( isOpen(pPager->fd) || pPager->noSync );
-  if( (pPager->noSync) || (pPager->journalMode==PAGER_JOURNALMODE_MEMORY)
+  if( pPager->noSync || (pPager->journalMode==PAGER_JOURNALMODE_MEMORY)
    || (sqlite3OsDeviceCharacteristics(pPager->fd)&SQLITE_IOCAP_SAFE_APPEND) 
   ){
     memcpy(zHeader, aJournalMagic, sizeof(aJournalMagic));
@@ -34625,7 +36103,6 @@
   if( pPager->journalOff==0 ){
     u32 iPageSize;               /* Page-size field of journal header */
     u32 iSectorSize;             /* Sector-size field of journal header */
-    u16 iPageSize16;             /* Copy of iPageSize in 16-bit variable */
 
     /* Read the page-size and sector-size journal header fields. */
     if( SQLITE_OK!=(rc = read32bits(pPager->jfd, iHdrOff+20, &iSectorSize))
@@ -34634,6 +36111,14 @@
       return rc;
     }
 
+    /* Versions of SQLite prior to 3.5.8 set the page-size field of the
+    ** journal header to zero. In this case, assume that the Pager.pageSize
+    ** variable is already set to the correct page size.
+    */
+    if( iPageSize==0 ){
+      iPageSize = pPager->pageSize;
+    }
+
     /* Check that the values read from the page-size and sector-size fields
     ** are within range. To be 'in range', both values need to be a power
     ** of two greater than or equal to 512 or 32, and not greater than their 
@@ -34655,10 +36140,8 @@
     ** Use a testcase() macro to make sure that malloc failure within 
     ** PagerSetPagesize() is tested.
     */
-    iPageSize16 = (u16)iPageSize;
-    rc = sqlite3PagerSetPagesize(pPager, &iPageSize16, -1);
+    rc = sqlite3PagerSetPagesize(pPager, &iPageSize, -1);
     testcase( rc!=SQLITE_OK );
-    assert( rc!=SQLITE_OK || iPageSize16==(u16)iPageSize );
 
     /* Update the assumed sector-size to match the value used by 
     ** the process that created this journal. If this journal was
@@ -34700,7 +36183,10 @@
   i64 jrnlSize;                    /* Size of journal file on disk */
   u32 cksum = 0;                   /* Checksum of string zMaster */
 
-  if( !zMaster || pPager->setMaster
+  assert( pPager->setMaster==0 );
+  assert( !pagerUseWal(pPager) );
+
+  if( !zMaster 
    || pPager->journalMode==PAGER_JOURNALMODE_MEMORY 
    || pPager->journalMode==PAGER_JOURNALMODE_OFF 
   ){
@@ -34736,7 +36222,6 @@
     return rc;
   }
   pPager->journalOff += (nMaster+20);
-  pPager->needSync = !pPager->noSync;
 
   /* If the pager is in peristent-journal mode, then the physical 
   ** journal-file may extend past the end of the master-journal name
@@ -34772,17 +36257,11 @@
 }
 
 /*
-** Unless the pager is in error-state, discard all in-memory pages. If
-** the pager is in error-state, then this call is a no-op.
-**
-** TODO: Why can we not reset the pager while in error state?
+** Discard the entire contents of the in-memory page-cache.
 */
 static void pager_reset(Pager *pPager){
-  if( SQLITE_OK==pPager->errCode ){
-    sqlite3BackupRestart(pPager->pBackup);
-    sqlite3PcacheClear(pPager->pPCache);
-    pPager->dbSizeValid = 0;
-  }
+  sqlite3BackupRestart(pPager->pBackup);
+  sqlite3PcacheClear(pPager->pPCache);
 }
 
 /*
@@ -34825,34 +36304,39 @@
 }
 
 /*
-** Return true if this pager uses a write-ahead log instead of the usual
-** rollback journal. Otherwise false.
-*/
-#ifndef SQLITE_OMIT_WAL
-static int pagerUseWal(Pager *pPager){
-  return (pPager->pWal!=0);
-}
-#else
-# define pagerUseWal(x) 0
-# define pagerRollbackWal(x) 0
-# define pagerWalFrames(v,w,x,y,z) 0
-# define pagerOpenWalIfPresent(z) SQLITE_OK
-# define pagerBeginReadTransaction(z) SQLITE_OK
-#endif
-
-/*
-** Unlock the database file. This function is a no-op if the pager
-** is in exclusive mode.
+** This function is a no-op if the pager is in exclusive mode and not
+** in the ERROR state. Otherwise, it switches the pager to PAGER_OPEN
+** state.
 **
-** If the pager is currently in error state, discard the contents of 
-** the cache and reset the Pager structure internal state. If there is
-** an open journal-file, then the next time a shared-lock is obtained
-** on the pager file (by this or any other process), it will be
-** treated as a hot-journal and rolled back.
+** If the pager is not in exclusive-access mode, the database file is
+** completely unlocked. If the file is unlocked and the file-system does
+** not exhibit the UNDELETABLE_WHEN_OPEN property, the journal file is
+** closed (if it is open).
+**
+** If the pager is in ERROR state when this function is called, the 
+** contents of the pager cache are discarded before switching back to 
+** the OPEN state. Regardless of whether the pager is in exclusive-mode
+** or not, any journal file left in the file-system will be treated
+** as a hot-journal and rolled back the next time a read-transaction
+** is opened (by this or by any other connection).
 */
 static void pager_unlock(Pager *pPager){
-  if( !pPager->exclusiveMode ){
-    int rc = SQLITE_OK;          /* Return code */
+
+  assert( pPager->eState==PAGER_READER 
+       || pPager->eState==PAGER_OPEN 
+       || pPager->eState==PAGER_ERROR 
+  );
+
+  sqlite3BitvecDestroy(pPager->pInJournal);
+  pPager->pInJournal = 0;
+  releaseAllSavepoints(pPager);
+
+  if( pagerUseWal(pPager) ){
+    assert( !isOpen(pPager->jfd) );
+    sqlite3WalEndReadTransaction(pPager->pWal);
+    pPager->eState = PAGER_OPEN;
+  }else if( !pPager->exclusiveMode ){
+    int rc;                       /* Error code returned by pagerUnlockDb() */
     int iDc = isOpen(pPager->fd)?sqlite3OsDeviceCharacteristics(pPager->fd):0;
 
     /* If the operating system support deletion of open files, then
@@ -34872,58 +36356,56 @@
       sqlite3OsClose(pPager->jfd);
     }
 
-    sqlite3BitvecDestroy(pPager->pInJournal);
-    pPager->pInJournal = 0;
-    releaseAllSavepoints(pPager);
-
-    /* If the file is unlocked, somebody else might change it. The
-    ** values stored in Pager.dbSize etc. might become invalid if
-    ** this happens.  One can argue that this doesn't need to be cleared
-    ** until the change-counter check fails in PagerSharedLock().
-    ** Clearing the page size cache here is being conservative.
+    /* If the pager is in the ERROR state and the call to unlock the database
+    ** file fails, set the current lock to UNKNOWN_LOCK. See the comment
+    ** above the #define for UNKNOWN_LOCK for an explanation of why this
+    ** is necessary.
     */
-    pPager->dbSizeValid = 0;
-
-    if( pagerUseWal(pPager) ){
-      sqlite3WalEndReadTransaction(pPager->pWal);
-    }else{
-      rc = osUnlock(pPager->fd, NO_LOCK);
+    rc = pagerUnlockDb(pPager, NO_LOCK);
+    if( rc!=SQLITE_OK && pPager->eState==PAGER_ERROR ){
+      pPager->eLock = UNKNOWN_LOCK;
     }
-    if( rc ){
-      pPager->errCode = rc;
-    }
-    IOTRACE(("UNLOCK %p\n", pPager))
 
-    /* If Pager.errCode is set, the contents of the pager cache cannot be
-    ** trusted. Now that the pager file is unlocked, the contents of the
-    ** cache can be discarded and the error code safely cleared.
+    /* The pager state may be changed from PAGER_ERROR to PAGER_OPEN here
+    ** without clearing the error code. This is intentional - the error
+    ** code is cleared and the cache reset in the block below.
     */
-    if( pPager->errCode ){
-      if( rc==SQLITE_OK ){
-        pPager->errCode = SQLITE_OK;
-      }
-      pager_reset(pPager);
-    }
-
+    assert( pPager->errCode || pPager->eState!=PAGER_ERROR );
     pPager->changeCountDone = 0;
-    pPager->state = PAGER_UNLOCK;
-    pPager->dbModified = 0;
+    pPager->eState = PAGER_OPEN;
   }
+
+  /* If Pager.errCode is set, the contents of the pager cache cannot be
+  ** trusted. Now that there are no outstanding references to the pager,
+  ** it can safely move back to PAGER_OPEN state. This happens in both
+  ** normal and exclusive-locking mode.
+  */
+  if( pPager->errCode ){
+    assert( !MEMDB );
+    pager_reset(pPager);
+    pPager->changeCountDone = pPager->tempFile;
+    pPager->eState = PAGER_OPEN;
+    pPager->errCode = SQLITE_OK;
+  }
+
+  pPager->journalOff = 0;
+  pPager->journalHdr = 0;
+  pPager->setMaster = 0;
 }
 
 /*
-** This function should be called when an IOERR, CORRUPT or FULL error
-** may have occurred. The first argument is a pointer to the pager 
-** structure, the second the error-code about to be returned by a pager 
-** API function. The value returned is a copy of the second argument 
-** to this function. 
+** This function is called whenever an IOERR or FULL error that requires
+** the pager to transition into the ERROR state may ahve occurred.
+** The first argument is a pointer to the pager structure, the second 
+** the error-code about to be returned by a pager API function. The 
+** value returned is a copy of the second argument to this function. 
 **
-** If the second argument is SQLITE_IOERR, SQLITE_CORRUPT, or SQLITE_FULL
-** the error becomes persistent. Until the persistent error is cleared,
-** subsequent API calls on this Pager will immediately return the same 
-** error code.
+** If the second argument is SQLITE_FULL, SQLITE_IOERR or one of the
+** IOERR sub-codes, the pager enters the ERROR state and the error code
+** is stored in Pager.errCode. While the pager remains in the ERROR state,
+** all major API calls on the Pager will immediately return Pager.errCode.
 **
-** A persistent error indicates that the contents of the pager-cache 
+** The ERROR state indicates that the contents of the pager-cache 
 ** cannot be trusted. This state can be cleared by completely discarding 
 ** the contents of the pager-cache. If a transaction was active when
 ** the persistent error occurred, then the rollback journal may need
@@ -34940,45 +36422,21 @@
   );
   if( rc2==SQLITE_FULL || rc2==SQLITE_IOERR ){
     pPager->errCode = rc;
+    pPager->eState = PAGER_ERROR;
   }
   return rc;
 }
 
 /*
-** Execute a rollback if a transaction is active and unlock the 
-** database file. 
-**
-** If the pager has already entered the error state, do not attempt 
-** the rollback at this time. Instead, pager_unlock() is called. The
-** call to pager_unlock() will discard all in-memory pages, unlock
-** the database file and clear the error state. If this means that
-** there is a hot-journal left in the file-system, the next connection
-** to obtain a shared lock on the pager (which may be this one) will
-** roll it back.
-**
-** If the pager has not already entered the error state, but an IO or
-** malloc error occurs during a rollback, then this will itself cause 
-** the pager to enter the error state. Which will be cleared by the
-** call to pager_unlock(), as described above.
-*/
-static void pagerUnlockAndRollback(Pager *pPager){
-  if( pPager->errCode==SQLITE_OK && pPager->state>=PAGER_RESERVED ){
-    sqlite3BeginBenignMalloc();
-    sqlite3PagerRollback(pPager);
-    sqlite3EndBenignMalloc();
-  }
-  pager_unlock(pPager);
-}
-
-/*
 ** This routine ends a transaction. A transaction is usually ended by 
 ** either a COMMIT or a ROLLBACK operation. This routine may be called 
 ** after rollback of a hot-journal, or if an error occurs while opening
 ** the journal file or writing the very first journal-header of a
 ** database transaction.
 ** 
-** If the pager is in PAGER_SHARED or PAGER_UNLOCK state when this
-** routine is called, it is a no-op (returns SQLITE_OK).
+** This routine is never called in PAGER_ERROR state. If it is called
+** in PAGER_NONE or PAGER_SHARED state and the lock held is less
+** exclusive than a RESERVED lock, it is a no-op.
 **
 ** Otherwise, any active savepoints are released.
 **
@@ -35009,13 +36467,9 @@
 **     DELETE and the pager is in exclusive mode, the method described under
 **     journalMode==PERSIST is used instead.
 **
-** After the journal is finalized, if running in non-exclusive mode, the
-** pager moves to PAGER_SHARED state (and downgrades the lock on the
-** database file accordingly).
-**
-** If the pager is running in exclusive mode and is in PAGER_SYNCED state,
-** it moves to PAGER_EXCLUSIVE. No locks are downgraded when running in
-** exclusive mode.
+** After the journal is finalized, the pager moves to PAGER_READER state.
+** If running in non-exclusive rollback mode, the lock on the file is 
+** downgraded to a SHARED_LOCK.
 **
 ** SQLITE_OK is returned if no error occurs. If an error occurs during
 ** any of the IO operations to finalize the journal file or unlock the
@@ -35030,11 +36484,26 @@
   int rc = SQLITE_OK;      /* Error code from journal finalization operation */
   int rc2 = SQLITE_OK;     /* Error code from db file unlock operation */
 
-  if( pPager->state<PAGER_RESERVED ){
+  /* Do nothing if the pager does not have an open write transaction
+  ** or at least a RESERVED lock. This function may be called when there
+  ** is no write-transaction active but a RESERVED or greater lock is
+  ** held under two circumstances:
+  **
+  **   1. After a successful hot-journal rollback, it is called with
+  **      eState==PAGER_NONE and eLock==EXCLUSIVE_LOCK.
+  **
+  **   2. If a connection with locking_mode=exclusive holding an EXCLUSIVE 
+  **      lock switches back to locking_mode=normal and then executes a
+  **      read-transaction, this function is called with eState==PAGER_READER 
+  **      and eLock==EXCLUSIVE_LOCK when the read-transaction is closed.
+  */
+  assert( assert_pager_state(pPager) );
+  assert( pPager->eState!=PAGER_ERROR );
+  if( pPager->eState<PAGER_WRITER_LOCKED && pPager->eLock<RESERVED_LOCK ){
     return SQLITE_OK;
   }
-  releaseAllSavepoints(pPager);
 
+  releaseAllSavepoints(pPager);
   assert( isOpen(pPager->jfd) || pPager->pInJournal==0 );
   if( isOpen(pPager->jfd) ){
     assert( !pagerUseWal(pPager) );
@@ -35050,14 +36519,11 @@
         rc = sqlite3OsTruncate(pPager->jfd, 0);
       }
       pPager->journalOff = 0;
-      pPager->journalStarted = 0;
     }else if( pPager->journalMode==PAGER_JOURNALMODE_PERSIST
       || (pPager->exclusiveMode && pPager->journalMode!=PAGER_JOURNALMODE_WAL)
     ){
       rc = zeroJournalHdr(pPager, hasMaster);
-      pager_error(pPager, rc);
       pPager->journalOff = 0;
-      pPager->journalStarted = 0;
     }else{
       /* This branch may be executed with Pager.journalMode==MEMORY if
       ** a hot-journal was just rolled back. In this case the journal
@@ -35073,50 +36539,78 @@
         rc = sqlite3OsDelete(pPager->pVfs, pPager->zJournal, 0);
       }
     }
+  }
 
 #ifdef SQLITE_CHECK_PAGES
-    sqlite3PcacheIterateDirty(pPager->pPCache, pager_set_pagehash);
-#endif
+  sqlite3PcacheIterateDirty(pPager->pPCache, pager_set_pagehash);
+  if( pPager->dbSize==0 && sqlite3PcacheRefCount(pPager->pPCache)>0 ){
+    PgHdr *p = pager_lookup(pPager, 1);
+    if( p ){
+      p->pageHash = 0;
+      sqlite3PagerUnref(p);
+    }
   }
+#endif
+
   sqlite3BitvecDestroy(pPager->pInJournal);
   pPager->pInJournal = 0;
   pPager->nRec = 0;
   sqlite3PcacheCleanAll(pPager->pPCache);
+  sqlite3PcacheTruncate(pPager->pPCache, pPager->dbSize);
 
   if( pagerUseWal(pPager) ){
+    /* Drop the WAL write-lock, if any. Also, if the connection was in 
+    ** locking_mode=exclusive mode but is no longer, drop the EXCLUSIVE 
+    ** lock held on the database file.
+    */
     rc2 = sqlite3WalEndWriteTransaction(pPager->pWal);
     assert( rc2==SQLITE_OK );
-    pPager->state = PAGER_SHARED;
-
-    /* If the connection was in locking_mode=exclusive mode but is no longer,
-    ** drop the EXCLUSIVE lock held on the database file.
-    */
-    if( !pPager->exclusiveMode && sqlite3WalExclusiveMode(pPager->pWal, 0) ){
-      rc2 = osUnlock(pPager->fd, SHARED_LOCK);
-    }
-  }else if( !pPager->exclusiveMode ){
-    rc2 = osUnlock(pPager->fd, SHARED_LOCK);
-    pPager->state = PAGER_SHARED;
+  }
+  if( !pPager->exclusiveMode 
+   && (!pagerUseWal(pPager) || sqlite3WalExclusiveMode(pPager->pWal, 0))
+  ){
+    rc2 = pagerUnlockDb(pPager, SHARED_LOCK);
     pPager->changeCountDone = 0;
-  }else if( pPager->state==PAGER_SYNCED ){
-    pPager->state = PAGER_EXCLUSIVE;
   }
+  pPager->eState = PAGER_READER;
   pPager->setMaster = 0;
-  pPager->needSync = 0;
-  pPager->dbModified = 0;
-
-  /* TODO: Is this optimal? Why is the db size invalidated here 
-  ** when the database file is not unlocked? */
-  pPager->dbOrigSize = 0;
-  sqlite3PcacheTruncate(pPager->pPCache, pPager->dbSize);
-  if( !MEMDB ){
-    pPager->dbSizeValid = 0;
-  }
 
   return (rc==SQLITE_OK?rc2:rc);
 }
 
 /*
+** Execute a rollback if a transaction is active and unlock the 
+** database file. 
+**
+** If the pager has already entered the ERROR state, do not attempt 
+** the rollback at this time. Instead, pager_unlock() is called. The
+** call to pager_unlock() will discard all in-memory pages, unlock
+** the database file and move the pager back to OPEN state. If this 
+** means that there is a hot-journal left in the file-system, the next 
+** connection to obtain a shared lock on the pager (which may be this one) 
+** will roll it back.
+**
+** If the pager has not already entered the ERROR state, but an IO or
+** malloc error occurs during a rollback, then this will itself cause 
+** the pager to enter the ERROR state. Which will be cleared by the
+** call to pager_unlock(), as described above.
+*/
+static void pagerUnlockAndRollback(Pager *pPager){
+  if( pPager->eState!=PAGER_ERROR && pPager->eState!=PAGER_OPEN ){
+    assert( assert_pager_state(pPager) );
+    if( pPager->eState>=PAGER_WRITER_LOCKED ){
+      sqlite3BeginBenignMalloc();
+      sqlite3PagerRollback(pPager);
+      sqlite3EndBenignMalloc();
+    }else if( !pPager->exclusiveMode ){
+      assert( pPager->eState==PAGER_READER );
+      pager_end_transaction(pPager, 0);
+    }
+  }
+  pager_unlock(pPager);
+}
+
+/*
 ** Parameter aData must point to a buffer of pPager->pageSize bytes
 ** of data. Compute and return a checksum based ont the contents of the 
 ** page of data and the current value of pPager->cksumInit.
@@ -35166,9 +36660,8 @@
 ** The page begins at offset *pOffset into the file. The *pOffset
 ** value is increased to the start of the next page in the journal.
 **
-** The isMainJrnl flag is true if this is the main rollback journal and
-** false for the statement journal.  The main rollback journal uses
-** checksums - the statement journal does not.
+** The main rollback journal uses checksums - the statement journal does 
+** not.
 **
 ** If the page number of the page record read from the (sub-)journal file
 ** is greater than the current value of Pager.dbSize, then playback is
@@ -35222,6 +36715,17 @@
   assert( aData );         /* Temp storage must have already been allocated */
   assert( pagerUseWal(pPager)==0 || (!isMainJrnl && isSavepnt) );
 
+  /* Either the state is greater than PAGER_WRITER_CACHEMOD (a transaction 
+  ** or savepoint rollback done at the request of the caller) or this is
+  ** a hot-journal rollback. If it is a hot-journal rollback, the pager
+  ** is in state OPEN and holds an EXCLUSIVE lock. Hot-journal rollback
+  ** only reads from the main journal, not the sub-journal.
+  */
+  assert( pPager->eState>=PAGER_WRITER_CACHEMOD
+       || (pPager->eState==PAGER_OPEN && pPager->eLock==EXCLUSIVE_LOCK)
+  );
+  assert( pPager->eState>=PAGER_WRITER_CACHEMOD || isMainJrnl );
+
   /* Read the page number and page data from the journal or sub-journal
   ** file. Return an error code to the caller if an IO error occurs.
   */
@@ -35258,7 +36762,6 @@
   if( pDone && (rc = sqlite3BitvecSet(pDone, pgno))!=SQLITE_OK ){
     return rc;
   }
-  assert( pPager->state==PAGER_RESERVED || pPager->state>=PAGER_EXCLUSIVE );
 
   /* When playing back page 1, restore the nReserve setting
   */
@@ -35267,7 +36770,7 @@
     pagerReportSize(pPager);
   }
 
-  /* If the pager is in RESERVED state, then there must be a copy of this
+  /* If the pager is in CACHEMOD state, then there must be a copy of this
   ** page in the pager cache. In this case just update the pager cache,
   ** not the database file. The page is left marked dirty in this case.
   **
@@ -35278,8 +36781,11 @@
   ** either. So the condition described in the above paragraph is not
   ** assert()able.
   **
-  ** If in EXCLUSIVE state, then we update the pager cache if it exists
-  ** and the main file. The page is then marked not dirty.
+  ** If in WRITER_DBMOD, WRITER_FINISHED or OPEN state, then we update the
+  ** pager cache if it exists and the main file. The page is then marked 
+  ** not dirty. Since this code is only executed in PAGER_OPEN state for
+  ** a hot-journal rollback, it is guaranteed that the page-cache is empty
+  ** if the pager is in OPEN state.
   **
   ** Ticket #1171:  The statement journal might contain page content that is
   ** different from the page content at the start of the transaction.
@@ -35305,6 +36811,7 @@
     pPg = pager_lookup(pPager, pgno);
   }
   assert( pPg || !MEMDB );
+  assert( pPager->eState!=PAGER_OPEN || pPg==0 );
   PAGERTRACE(("PLAYBACK %d page %d hash(%08x) %s\n",
            PAGERID(pPager), pgno, pager_datahash(pPager->pageSize, (u8*)aData),
            (isMainJrnl?"main-journal":"sub-journal")
@@ -35314,8 +36821,8 @@
   }else{
     isSynced = (pPg==0 || 0==(pPg->flags & PGHDR_NEED_SYNC));
   }
-  if( (pPager->state>=PAGER_EXCLUSIVE)
-   && isOpen(pPager->fd)
+  if( isOpen(pPager->fd)
+   && (pPager->eState>=PAGER_WRITER_DBMOD || pPager->eState==PAGER_OPEN)
    && isSynced
   ){
     i64 ofst = (pgno-1)*(i64)pPager->pageSize;
@@ -35391,9 +36898,8 @@
       assert( !pagerUseWal(pPager) );
       sqlite3PcacheMakeClean(pPg);
     }
-#ifdef SQLITE_CHECK_PAGES
-    pPg->pageHash = pager_pagehash(pPg);
-#endif
+    pager_set_pagehash(pPg);
+
     /* If this was page 1, then restore the value of Pager.dbFileVers.
     ** Do this before any decoding. */
     if( pgno==1 ){
@@ -35545,10 +37051,10 @@
 ** file in the file-system. This only happens when committing a transaction,
 ** or rolling back a transaction (including rolling back a hot-journal).
 **
-** If the main database file is not open, or an exclusive lock is not
-** held, this function is a no-op. Otherwise, the size of the file is
-** changed to nPage pages (nPage*pPager->pageSize bytes). If the file
-** on disk is currently larger than nPage pages, then use the VFS
+** If the main database file is not open, or the pager is not in either
+** DBMOD or OPEN state, this function is a no-op. Otherwise, the size 
+** of the file is changed to nPage pages (nPage*pPager->pageSize bytes). 
+** If the file on disk is currently larger than nPage pages, then use the VFS
 ** xTruncate() method to truncate it.
 **
 ** Or, it might might be the case that the file on disk is smaller than 
@@ -35562,8 +37068,14 @@
 */
 static int pager_truncate(Pager *pPager, Pgno nPage){
   int rc = SQLITE_OK;
-  if( pPager->state>=PAGER_EXCLUSIVE && isOpen(pPager->fd) ){
+  assert( pPager->eState!=PAGER_ERROR );
+  assert( pPager->eState!=PAGER_READER );
+  
+  if( isOpen(pPager->fd) 
+   && (pPager->eState>=PAGER_WRITER_DBMOD || pPager->eState==PAGER_OPEN) 
+  ){
     i64 currentSize, newSize;
+    assert( pPager->eLock==EXCLUSIVE_LOCK );
     /* TODO: Is it safe to use Pager.dbFileSize here? */
     rc = sqlite3OsFileSize(pPager->fd, &currentSize);
     newSize = pPager->pageSize*(i64)nPage;
@@ -35687,7 +37199,7 @@
   */
   assert( isOpen(pPager->jfd) );
   rc = sqlite3OsFileSize(pPager->jfd, &szJ);
-  if( rc!=SQLITE_OK || szJ==0 ){
+  if( rc!=SQLITE_OK ){
     goto end_playback;
   }
 
@@ -35721,7 +37233,7 @@
   while( 1 ){
     /* Read the next journal header from the journal file.  If there are
     ** not enough bytes left in the journal file for a complete header, or
-    ** it is corrupted, then a process must of failed while writing it.
+    ** it is corrupted, then a process must have failed while writing it.
     ** This indicates nothing more needs to be rolled back.
     */
     rc = readJournalHdr(pPager, isHot, szJ, &nRec, &mxPg);
@@ -35835,10 +37347,9 @@
     rc = readMasterJournal(pPager->jfd, zMaster, pPager->pVfs->mxPathname+1);
     testcase( rc!=SQLITE_OK );
   }
-  if( rc==SQLITE_OK && pPager->noSync==0 && pPager->state>=PAGER_EXCLUSIVE ){
-    rc = sqlite3OsSync(pPager->fd, pPager->sync_flags);
-  }
-  if( rc==SQLITE_OK && pPager->noSync==0 && pPager->state>=PAGER_EXCLUSIVE ){
+  if( rc==SQLITE_OK && !pPager->noSync 
+   && (pPager->eState>=PAGER_WRITER_DBMOD || pPager->eState==PAGER_OPEN)
+  ){
     rc = sqlite3OsSync(pPager->fd, pPager->sync_flags);
   }
   if( rc==SQLITE_OK ){
@@ -35880,7 +37391,7 @@
   int isInWal = 0;             /* True if page is in log file */
   int pgsz = pPager->pageSize; /* Number of bytes to read */
 
-  assert( pPager->state>=PAGER_SHARED && !MEMDB );
+  assert( pPager->eState>=PAGER_READER && !MEMDB );
   assert( isOpen(pPager->fd) );
 
   if( NEVER(!isOpen(pPager->fd)) ){
@@ -36027,6 +37538,14 @@
       sqlite3BackupUpdate(pPager->pBackup, p->pgno, (u8 *)p->pData);
     }
   }
+
+#ifdef SQLITE_CHECK_PAGES
+  {
+    PgHdr *p;
+    for(p=pList; p; p=p->pDirty) pager_set_pagehash(p);
+  }
+#endif
+
   return rc;
 }
 
@@ -36043,6 +37562,7 @@
   int changed = 0;                /* True if cache must be reset */
 
   assert( pagerUseWal(pPager) );
+  assert( pPager->eState==PAGER_OPEN || pPager->eState==PAGER_READER );
 
   /* sqlite3WalEndReadTransaction() was not called for the previous
   ** transaction in locking_mode=EXCLUSIVE.  So call it now.  If we
@@ -36052,20 +37572,71 @@
   sqlite3WalEndReadTransaction(pPager->pWal);
 
   rc = sqlite3WalBeginReadTransaction(pPager->pWal, &changed);
-  if( rc==SQLITE_OK ){
-    int dummy;
-    if( changed ){
-      pager_reset(pPager);
-      assert( pPager->errCode || pPager->dbSizeValid==0 );
-    }
-    rc = sqlite3PagerPagecount(pPager, &dummy);
+  if( rc!=SQLITE_OK || changed ){
+    pager_reset(pPager);
   }
-  pPager->state = PAGER_SHARED;
 
   return rc;
 }
+#endif
 
 /*
+** This function is called as part of the transition from PAGER_OPEN
+** to PAGER_READER state to determine the size of the database file
+** in pages (assuming the page size currently stored in Pager.pageSize).
+**
+** If no error occurs, SQLITE_OK is returned and the size of the database
+** in pages is stored in *pnPage. Otherwise, an error code (perhaps
+** SQLITE_IOERR_FSTAT) is returned and *pnPage is left unmodified.
+*/
+static int pagerPagecount(Pager *pPager, Pgno *pnPage){
+  Pgno nPage;                     /* Value to return via *pnPage */
+
+  /* Query the WAL sub-system for the database size. The WalDbsize()
+  ** function returns zero if the WAL is not open (i.e. Pager.pWal==0), or
+  ** if the database size is not available. The database size is not
+  ** available from the WAL sub-system if the log file is empty or
+  ** contains no valid committed transactions.
+  */
+  assert( pPager->eState==PAGER_OPEN );
+  assert( pPager->eLock>=SHARED_LOCK || pPager->noReadlock );
+  nPage = sqlite3WalDbsize(pPager->pWal);
+
+  /* If the database size was not available from the WAL sub-system,
+  ** determine it based on the size of the database file. If the size
+  ** of the database file is not an integer multiple of the page-size,
+  ** round down to the nearest page. Except, any file larger than 0
+  ** bytes in size is considered to contain at least one page.
+  */
+  if( nPage==0 ){
+    i64 n = 0;                    /* Size of db file in bytes */
+    assert( isOpen(pPager->fd) || pPager->tempFile );
+    if( isOpen(pPager->fd) ){
+      int rc = sqlite3OsFileSize(pPager->fd, &n);
+      if( rc!=SQLITE_OK ){
+        return rc;
+      }
+    }
+    nPage = (Pgno)(n / pPager->pageSize);
+    if( nPage==0 && n>0 ){
+      nPage = 1;
+    }
+  }
+
+  /* If the current number of pages in the file is greater than the
+  ** configured maximum pager number, increase the allowed limit so
+  ** that the file can be read.
+  */
+  if( nPage>pPager->mxPgno ){
+    pPager->mxPgno = (Pgno)nPage;
+  }
+
+  *pnPage = nPage;
+  return SQLITE_OK;
+}
+
+#ifndef SQLITE_OMIT_WAL
+/*
 ** Check if the *-wal file that corresponds to the database opened by pPager
 ** exists if the database is not empy, or verify that the *-wal file does
 ** not exist (by deleting it) if the database file is empty.
@@ -36077,8 +37648,6 @@
 **
 ** Return SQLITE_OK or an error code.
 **
-** If the WAL file is opened, also open a snapshot (read transaction).
-**
 ** The caller must hold a SHARED lock on the database file to call this
 ** function. Because an EXCLUSIVE lock on the db file is required to delete 
 ** a WAL on a none-empty database, this ensures there is no race condition 
@@ -36087,11 +37656,14 @@
 */
 static int pagerOpenWalIfPresent(Pager *pPager){
   int rc = SQLITE_OK;
+  assert( pPager->eState==PAGER_OPEN );
+  assert( pPager->eLock>=SHARED_LOCK || pPager->noReadlock );
+
   if( !pPager->tempFile ){
     int isWal;                    /* True if WAL file exists */
-    int nPage;                    /* Size of the database file */
-    assert( pPager->state>=SHARED_LOCK );
-    rc = sqlite3PagerPagecount(pPager, &nPage);
+    Pgno nPage;                   /* Size of the database file */
+
+    rc = pagerPagecount(pPager, &nPage);
     if( rc ) return rc;
     if( nPage==0 ){
       rc = sqlite3OsDelete(pPager->pVfs, pPager->zWal, 0);
@@ -36103,11 +37675,8 @@
     }
     if( rc==SQLITE_OK ){
       if( isWal ){
-        pager_reset(pPager);
+        testcase( sqlite3PcachePagecount(pPager->pPCache)==0 );
         rc = sqlite3PagerOpenWal(pPager, 0);
-        if( rc==SQLITE_OK ){
-          rc = pagerBeginReadTransaction(pPager);
-        }
       }else if( pPager->journalMode==PAGER_JOURNALMODE_WAL ){
         pPager->journalMode = PAGER_JOURNALMODE_DELETE;
       }
@@ -36159,7 +37728,8 @@
   int rc = SQLITE_OK;      /* Return code */
   Bitvec *pDone = 0;       /* Bitvec to ensure pages played back only once */
 
-  assert( pPager->state>=PAGER_SHARED );
+  assert( pPager->eState!=PAGER_ERROR );
+  assert( pPager->eState>=PAGER_WRITER_LOCKED );
 
   /* Allocate a bitvec to use to store the set of pages rolled back */
   if( pSavepoint ){
@@ -36173,6 +37743,7 @@
   ** being reverted was opened.
   */
   pPager->dbSize = pSavepoint ? pSavepoint->nOrig : pPager->dbOrigSize;
+  pPager->changeCountDone = pPager->tempFile;
 
   if( !pSavepoint && pagerUseWal(pPager) ){
     return pagerRollbackWal(pPager);
@@ -36297,7 +37868,6 @@
   pPager->noSync =  (level==1 || pPager->tempFile) ?1:0;
   pPager->fullSync = (level==3 && !pPager->tempFile) ?1:0;
   pPager->sync_flags = (bFullFsync?SQLITE_SYNC_FULL:SQLITE_SYNC_NORMAL);
-  if( pPager->noSync ) pPager->needSync = 0;
 }
 #endif
 
@@ -36379,7 +37949,7 @@
 **
 ** If the pager is in the error state when this function is called, it
 ** is a no-op. The value returned is the error state error code (i.e. 
-** one of SQLITE_IOERR, SQLITE_CORRUPT or SQLITE_FULL).
+** one of SQLITE_IOERR, an SQLITE_IOERR_xxx sub-code or SQLITE_FULL).
 **
 ** Otherwise, if all of the following are true:
 **
@@ -36403,28 +37973,48 @@
 ** function was called, or because the memory allocation attempt failed, 
 ** then *pPageSize is set to the old, retained page size before returning.
 */
-SQLITE_PRIVATE int sqlite3PagerSetPagesize(Pager *pPager, u16 *pPageSize, int nReserve){
-  int rc = pPager->errCode;
+SQLITE_PRIVATE int sqlite3PagerSetPagesize(Pager *pPager, u32 *pPageSize, int nReserve){
+  int rc = SQLITE_OK;
 
-  if( rc==SQLITE_OK ){
-    u16 pageSize = *pPageSize;
-    assert( pageSize==0 || (pageSize>=512 && pageSize<=SQLITE_MAX_PAGE_SIZE) );
-    if( (pPager->memDb==0 || pPager->dbSize==0)
-     && sqlite3PcacheRefCount(pPager->pPCache)==0 
-     && pageSize && pageSize!=pPager->pageSize 
-    ){
-      char *pNew = (char *)sqlite3PageMalloc(pageSize);
-      if( !pNew ){
-        rc = SQLITE_NOMEM;
-      }else{
-        pager_reset(pPager);
-        pPager->pageSize = pageSize;
-        sqlite3PageFree(pPager->pTmpSpace);
-        pPager->pTmpSpace = pNew;
-        sqlite3PcacheSetPageSize(pPager->pPCache, pageSize);
-      }
+  /* It is not possible to do a full assert_pager_state() here, as this
+  ** function may be called from within PagerOpen(), before the state
+  ** of the Pager object is internally consistent.
+  **
+  ** At one point this function returned an error if the pager was in 
+  ** PAGER_ERROR state. But since PAGER_ERROR state guarantees that
+  ** there is at least one outstanding page reference, this function
+  ** is a no-op for that case anyhow.
+  */
+
+  u32 pageSize = *pPageSize;
+  assert( pageSize==0 || (pageSize>=512 && pageSize<=SQLITE_MAX_PAGE_SIZE) );
+  if( (pPager->memDb==0 || pPager->dbSize==0)
+   && sqlite3PcacheRefCount(pPager->pPCache)==0 
+   && pageSize && pageSize!=(u32)pPager->pageSize 
+  ){
+    char *pNew = NULL;             /* New temp space */
+    i64 nByte = 0;
+
+    if( pPager->eState>PAGER_OPEN && isOpen(pPager->fd) ){
+      rc = sqlite3OsFileSize(pPager->fd, &nByte);
     }
-    *pPageSize = (u16)pPager->pageSize;
+    if( rc==SQLITE_OK ){
+      pNew = (char *)sqlite3PageMalloc(pageSize);
+      if( !pNew ) rc = SQLITE_NOMEM;
+    }
+
+    if( rc==SQLITE_OK ){
+      pager_reset(pPager);
+      pPager->dbSize = (Pgno)(nByte/pageSize);
+      pPager->pageSize = pageSize;
+      sqlite3PageFree(pPager->pTmpSpace);
+      pPager->pTmpSpace = pNew;
+      sqlite3PcacheSetPageSize(pPager->pPCache, pageSize);
+    }
+  }
+
+  *pPageSize = pPager->pageSize;
+  if( rc==SQLITE_OK ){
     if( nReserve<0 ) nReserve = pPager->nReserve;
     assert( nReserve>=0 && nReserve<1000 );
     pPager->nReserve = (i16)nReserve;
@@ -36453,13 +38043,11 @@
 ** Regardless of mxPage, return the current maximum page count.
 */
 SQLITE_PRIVATE int sqlite3PagerMaxPageCount(Pager *pPager, int mxPage){
-  int nPage;
   if( mxPage>0 ){
     pPager->mxPgno = mxPage;
   }
-  if( pPager->state!=PAGER_UNLOCK ){
-    sqlite3PagerPagecount(pPager, &nPage);
-    assert( (int)pPager->mxPgno>=nPage );
+  if( pPager->eState!=PAGER_OPEN && pPager->mxPgno<pPager->dbSize ){
+    pPager->mxPgno = pPager->dbSize;
   }
   return pPager->mxPgno;
 }
@@ -36524,66 +38112,16 @@
 }
 
 /*
-** Return the total number of pages in the database file associated 
-** with pPager. Normally, this is calculated as (<db file size>/<page-size>).
+** This function may only be called when a read-transaction is open on
+** the pager. It returns the total number of pages in the database.
+**
 ** However, if the file is between 1 and <page-size> bytes in size, then 
 ** this is considered a 1 page file.
-**
-** If the pager is in error state when this function is called, then the
-** error state error code is returned and *pnPage left unchanged. Or,
-** if the file system has to be queried for the size of the file and
-** the query attempt returns an IO error, the IO error code is returned
-** and *pnPage is left unchanged.
-**
-** Otherwise, if everything is successful, then SQLITE_OK is returned
-** and *pnPage is set to the number of pages in the database.
 */
-SQLITE_PRIVATE int sqlite3PagerPagecount(Pager *pPager, int *pnPage){
-  Pgno nPage = 0;           /* Value to return via *pnPage */
-
-  /* Determine the number of pages in the file. Store this in nPage. */
-  if( pPager->dbSizeValid ){
-    nPage = pPager->dbSize;
-  }else{
-    int rc;                 /* Error returned by OsFileSize() */
-    i64 n = 0;              /* File size in bytes returned by OsFileSize() */
-
-    if( pagerUseWal(pPager) && pPager->state!=PAGER_UNLOCK ){
-      sqlite3WalDbsize(pPager->pWal, &nPage);
-    }
-
-    if( nPage==0 ){
-      assert( isOpen(pPager->fd) || pPager->tempFile );
-      if( isOpen(pPager->fd) ){
-        if( SQLITE_OK!=(rc = sqlite3OsFileSize(pPager->fd, &n)) ){
-          pager_error(pPager, rc);
-          return rc;
-        }
-      }
-      if( n>0 && n<pPager->pageSize ){
-        nPage = 1;
-      }else{
-        nPage = (Pgno)(n / pPager->pageSize);
-      }
-    }
-    if( pPager->state!=PAGER_UNLOCK ){
-      pPager->dbSize = nPage;
-      pPager->dbFileSize = nPage;
-      pPager->dbSizeValid = 1;
-    }
-  }
-
-  /* If the current number of pages in the file is greater than the 
-  ** configured maximum pager number, increase the allowed limit so
-  ** that the file can be read.
-  */
-  if( nPage>pPager->mxPgno ){
-    pPager->mxPgno = (Pgno)nPage;
-  }
-
-  /* Set the output variable and return SQLITE_OK */
-  *pnPage = nPage;
-  return SQLITE_OK;
+SQLITE_PRIVATE void sqlite3PagerPagecount(Pager *pPager, int *pnPage){
+  assert( pPager->eState>=PAGER_READER );
+  assert( pPager->eState!=PAGER_WRITER_FINISHED );
+  *pnPage = (int)pPager->dbSize;
 }
 
 
@@ -36604,38 +38142,19 @@
 static int pager_wait_on_lock(Pager *pPager, int locktype){
   int rc;                              /* Return code */
 
-  /* The OS lock values must be the same as the Pager lock values */
-  assert( PAGER_SHARED==SHARED_LOCK );
-  assert( PAGER_RESERVED==RESERVED_LOCK );
-  assert( PAGER_EXCLUSIVE==EXCLUSIVE_LOCK );
-
-  /* If the file is currently unlocked then the size must be unknown. It
-  ** must not have been modified at this point.
-  */
-  assert( pPager->state>=PAGER_SHARED || pPager->dbSizeValid==0 );
-  assert( pPager->state>=PAGER_SHARED || pPager->dbModified==0 );
-
   /* Check that this is either a no-op (because the requested lock is 
   ** already held, or one of the transistions that the busy-handler
   ** may be invoked during, according to the comment above
   ** sqlite3PagerSetBusyhandler().
   */
-  assert( (pPager->state>=locktype)
-       || (pPager->state==PAGER_UNLOCK && locktype==PAGER_SHARED)
-       || (pPager->state==PAGER_RESERVED && locktype==PAGER_EXCLUSIVE)
+  assert( (pPager->eLock>=locktype)
+       || (pPager->eLock==NO_LOCK && locktype==SHARED_LOCK)
+       || (pPager->eLock==RESERVED_LOCK && locktype==EXCLUSIVE_LOCK)
   );
 
-  if( pPager->state>=locktype ){
-    rc = SQLITE_OK;
-  }else{
-    do {
-      rc = sqlite3OsLock(pPager->fd, locktype);
-    }while( rc==SQLITE_BUSY && pPager->xBusyHandler(pPager->pBusyHandlerArg) );
-    if( rc==SQLITE_OK ){
-      pPager->state = (u8)locktype;
-      IOTRACE(("LOCK %p %d\n", pPager, locktype))
-    }
-  }
+  do {
+    rc = pagerLockDb(pPager, locktype);
+  }while( rc==SQLITE_BUSY && pPager->xBusyHandler(pPager->pBusyHandlerArg) );
   return rc;
 }
 
@@ -36680,9 +38199,8 @@
 ** truncation will be done when the current transaction is committed.
 */
 SQLITE_PRIVATE void sqlite3PagerTruncateImage(Pager *pPager, Pgno nPage){
-  assert( pPager->dbSizeValid );
   assert( pPager->dbSize>=nPage );
-  assert( pPager->state>=PAGER_RESERVED );
+  assert( pPager->eState>=PAGER_WRITER_CACHEMOD );
   pPager->dbSize = nPage;
   assertTruncateConstraint(pPager);
 }
@@ -36732,7 +38250,7 @@
 
   disable_simulated_io_errors();
   sqlite3BeginBenignMalloc();
-  pPager->errCode = 0;
+  /* pPager->errCode = 0; */
   pPager->exclusiveMode = 0;
 #ifndef SQLITE_OMIT_WAL
   sqlite3WalClose(pPager->pWal,
@@ -36745,14 +38263,19 @@
   if( MEMDB ){
     pager_unlock(pPager);
   }else{
-    /* Set Pager.journalHdr to -1 for the benefit of the pager_playback() 
-    ** call which may be made from within pagerUnlockAndRollback(). If it
-    ** is not -1, then the unsynced portion of an open journal file may
-    ** be played back into the database. If a power failure occurs while
-    ** this is happening, the database may become corrupt.
+    /* If it is open, sync the journal file before calling UnlockAndRollback.
+    ** If this is not done, then an unsynced portion of the open journal 
+    ** file may be played back into the database. If a power failure occurs 
+    ** while this is happening, the database could become corrupt.
+    **
+    ** If an error occurs while trying to sync the journal, shift the pager
+    ** into the ERROR state. This causes UnlockAndRollback to unlock the
+    ** database and close the journal file without attempting to roll it
+    ** back or finalize it. The next database user will have to do hot-journal
+    ** rollback before accessing the database file.
     */
     if( isOpen(pPager->jfd) ){
-      pPager->errCode = pagerSyncHotJournal(pPager);
+      pager_error(pPager, pagerSyncHotJournal(pPager));
     }
     pagerUnlockAndRollback(pPager);
   }
@@ -36797,9 +38320,9 @@
 ** been written to the journal have actually reached the surface of the
 ** disk and can be restored in the event of a hot-journal rollback.
 **
-** If the Pager.needSync flag is not set, then this function is a
-** no-op. Otherwise, the actions required depend on the journal-mode
-** and the device characteristics of the the file-system, as follows:
+** If the Pager.noSync flag is set, then this function is a no-op.
+** Otherwise, the actions required depend on the journal-mode and the 
+** device characteristics of the the file-system, as follows:
 **
 **   * If the journal file is an in-memory journal file, no action need
 **     be taken.
@@ -36823,18 +38346,25 @@
 **     if( NOT SEQUENTIAL ) xSync(<journal file>);
 **   }
 **
-** The Pager.needSync flag is never be set for temporary files, or any
-** file operating in no-sync mode (Pager.noSync set to non-zero).
-**
 ** If successful, this routine clears the PGHDR_NEED_SYNC flag of every 
 ** page currently held in memory before returning SQLITE_OK. If an IO
 ** error is encountered, then the IO error code is returned to the caller.
 */
-static int syncJournal(Pager *pPager){
-  if( pPager->needSync ){
+static int syncJournal(Pager *pPager, int newHdr){
+  int rc;                         /* Return code */
+
+  assert( pPager->eState==PAGER_WRITER_CACHEMOD
+       || pPager->eState==PAGER_WRITER_DBMOD
+  );
+  assert( assert_pager_state(pPager) );
+  assert( !pagerUseWal(pPager) );
+
+  rc = sqlite3PagerExclusiveLock(pPager);
+  if( rc!=SQLITE_OK ) return rc;
+
+  if( !pPager->noSync ){
     assert( !pPager->tempFile );
-    if( pPager->journalMode!=PAGER_JOURNALMODE_MEMORY ){
-      int rc;                              /* Return code */
+    if( isOpen(pPager->jfd) && pPager->journalMode!=PAGER_JOURNALMODE_MEMORY ){
       const int iDc = sqlite3OsDeviceCharacteristics(pPager->fd);
       assert( isOpen(pPager->jfd) );
 
@@ -36909,17 +38439,25 @@
         );
         if( rc!=SQLITE_OK ) return rc;
       }
-    }
 
-    /* The journal file was just successfully synced. Set Pager.needSync 
-    ** to zero and clear the PGHDR_NEED_SYNC flag on all pagess.
-    */
-    pPager->needSync = 0;
-    pPager->journalStarted = 1;
-    pPager->journalHdr = pPager->journalOff;
-    sqlite3PcacheClearSyncFlags(pPager->pPCache);
+      pPager->journalHdr = pPager->journalOff;
+      if( newHdr && 0==(iDc&SQLITE_IOCAP_SAFE_APPEND) ){
+        pPager->nRec = 0;
+        rc = writeJournalHdr(pPager);
+        if( rc!=SQLITE_OK ) return rc;
+      }
+    }else{
+      pPager->journalHdr = pPager->journalOff;
+    }
   }
 
+  /* Unless the pager is in noSync mode, the journal file was just 
+  ** successfully synced. Either way, clear the PGHDR_NEED_SYNC flag on 
+  ** all pages.
+  */
+  sqlite3PcacheClearSyncFlags(pPager->pPCache);
+  pPager->eState = PAGER_WRITER_DBMOD;
+  assert( assert_pager_state(pPager) );
   return SQLITE_OK;
 }
 
@@ -36956,27 +38494,12 @@
 ** be obtained, SQLITE_BUSY is returned.
 */
 static int pager_write_pagelist(Pager *pPager, PgHdr *pList){
-  int rc;                              /* Return code */
+  int rc = SQLITE_OK;                  /* Return code */
 
-  /* At this point there may be either a RESERVED or EXCLUSIVE lock on the
-  ** database file. If there is already an EXCLUSIVE lock, the following
-  ** call is a no-op.
-  **
-  ** Moving the lock from RESERVED to EXCLUSIVE actually involves going
-  ** through an intermediate state PENDING.   A PENDING lock prevents new
-  ** readers from attaching to the database but is unsufficient for us to
-  ** write.  The idea of a PENDING lock is to prevent new readers from
-  ** coming in while we wait for existing readers to clear.
-  **
-  ** While the pager is in the RESERVED state, the original database file
-  ** is unchanged and we can rollback without having to playback the
-  ** journal into the original database file.  Once we transition to
-  ** EXCLUSIVE, it means the database file has been changed and any rollback
-  ** will require a journal playback.
-  */
+  /* This function is only called for rollback pagers in WRITER_DBMOD state. */
   assert( !pagerUseWal(pPager) );
-  assert( pPager->state>=PAGER_RESERVED );
-  rc = pager_wait_on_lock(pPager, EXCLUSIVE_LOCK);
+  assert( pPager->eState==PAGER_WRITER_DBMOD );
+  assert( pPager->eLock==EXCLUSIVE_LOCK );
 
   /* If the file is a temp-file has not yet been opened, open it now. It
   ** is not possible for rc to be other than SQLITE_OK if this branch
@@ -36990,9 +38513,11 @@
   /* Before the first write, give the VFS a hint of what the final
   ** file size will be.
   */
-  if( pPager->dbSize > (pPager->dbOrigSize+1) && isOpen(pPager->fd) ){
+  assert( rc!=SQLITE_OK || isOpen(pPager->fd) );
+  if( rc==SQLITE_OK && pPager->dbSize>pPager->dbHintSize ){
     sqlite3_int64 szFile = pPager->pageSize * (sqlite3_int64)pPager->dbSize;
     sqlite3OsFileControl(pPager->fd, SQLITE_FCNTL_SIZE_HINT, &szFile);
+    pPager->dbHintSize = pPager->dbSize;
   }
 
   while( rc==SQLITE_OK && pList ){
@@ -37010,6 +38535,8 @@
       i64 offset = (pgno-1)*(i64)pPager->pageSize;   /* Offset to write */
       char *pData;                                   /* Data to write */    
 
+      assert( (pList->flags&PGHDR_NEED_SYNC)==0 );
+
       /* Encode the database */
       CODEC2(pPager, pList->pData, pgno, 6, return SQLITE_NOMEM, pData);
 
@@ -37038,9 +38565,7 @@
     }else{
       PAGERTRACE(("NOSTORE %d page %d\n", PAGERID(pPager), pgno));
     }
-#ifdef SQLITE_CHECK_PAGES
-    pList->pageHash = pager_pagehash(pList);
-#endif
+    pager_set_pagehash(pList);
     pList = pList->pDirty;
   }
 
@@ -37152,9 +38677,14 @@
   ** The doNotSpill flag inhibits all cache spilling regardless of whether
   ** or not a sync is required.  This is set during a rollback.
   **
-  ** Spilling is also inhibited when in an error state.
+  ** Spilling is also prohibited when in an error state since that could
+  ** lead to database corruption.   In the current implementaton it 
+  ** is impossible for sqlite3PCacheFetch() to be called with createFlag==1
+  ** while in the error state, hence it is impossible for this routine to
+  ** be called in the error state.  Nevertheless, we include a NEVER()
+  ** test for the error state as a safeguard against future changes.
   */
-  if( pPager->errCode ) return SQLITE_OK;
+  if( NEVER(pPager->errCode) ) return SQLITE_OK;
   if( pPager->doNotSpill ) return SQLITE_OK;
   if( pPager->doNotSyncSpill && (pPg->flags & PGHDR_NEED_SYNC)!=0 ){
     return SQLITE_OK;
@@ -37172,16 +38702,10 @@
   }else{
   
     /* Sync the journal file if required. */
-    if( pPg->flags&PGHDR_NEED_SYNC ){
-      assert( !pPager->noSync );
-      rc = syncJournal(pPager);
-      if( rc==SQLITE_OK && 
-        !(pPager->journalMode==PAGER_JOURNALMODE_MEMORY) &&
-        !(sqlite3OsDeviceCharacteristics(pPager->fd)&SQLITE_IOCAP_SAFE_APPEND)
-      ){
-        pPager->nRec = 0;
-        rc = writeJournalHdr(pPager);
-      }
+    if( pPg->flags&PGHDR_NEED_SYNC 
+     || pPager->eState==PAGER_WRITER_CACHEMOD
+    ){
+      rc = syncJournal(pPager, 1);
     }
   
     /* If the page number of this page is larger than the current size of
@@ -37219,6 +38743,7 @@
   
     /* Write the contents of the page out to the database file. */
     if( rc==SQLITE_OK ){
+      assert( (pPg->flags&PGHDR_NEED_SYNC)==0 );
       rc = pager_write_pagelist(pPager, pPg);
     }
   }
@@ -37229,7 +38754,7 @@
     sqlite3PcacheMakeClean(pPg);
   }
 
-  return pager_error(pPager, rc);
+  return pager_error(pPager, rc); 
 }
 
 
@@ -37284,7 +38809,7 @@
   int useJournal = (flags & PAGER_OMIT_JOURNAL)==0; /* False to omit journal */
   int noReadlock = (flags & PAGER_NO_READLOCK)!=0;  /* True to omit read-lock */
   int pcacheSize = sqlite3PcacheSize();       /* Bytes to allocate for PCache */
-  u16 szPageDflt = SQLITE_DEFAULT_PAGE_SIZE;  /* Default page size */
+  u32 szPageDflt = SQLITE_DEFAULT_PAGE_SIZE;  /* Default page size */
 
   /* Figure out how much space is required for each journal file-handle
   ** (there are two of them, the main journal and the sub-journal). This
@@ -37303,6 +38828,13 @@
   /* Set the output variable to NULL in case an error occurs. */
   *ppPager = 0;
 
+#ifndef SQLITE_OMIT_MEMORYDB
+  if( flags & PAGER_MEMORY ){
+    memDb = 1;
+    zFilename = 0;
+  }
+#endif
+
   /* Compute and store the full pathname in an allocated buffer pointed
   ** to by zPathname, length nPathname. Or, if this is a temporary file,
   ** leave both nPathname and zPathname set to 0.
@@ -37313,17 +38845,8 @@
     if( zPathname==0 ){
       return SQLITE_NOMEM;
     }
-#ifndef SQLITE_OMIT_MEMORYDB
-    if( strcmp(zFilename,":memory:")==0 ){
-      memDb = 1;
-      zPathname[0] = 0;
-    }else
-#endif
-    {
-      zPathname[0] = 0; /* Make sure initialized even if FullPathname() fails */
-      rc = sqlite3OsFullPathname(pVfs, zFilename, nPathname, zPathname);
-    }
-
+    zPathname[0] = 0; /* Make sure initialized even if FullPathname() fails */
+    rc = sqlite3OsFullPathname(pVfs, zFilename, nPathname, zPathname);
     nPathname = sqlite3Strlen30(zPathname);
     if( rc==SQLITE_OK && nPathname+8>pVfs->mxPathname ){
       /* This branch is taken when the journal path required by
@@ -37378,19 +38901,15 @@
 
   /* Fill in the Pager.zFilename and Pager.zJournal buffers, if required. */
   if( zPathname ){
+    assert( nPathname>0 );
     pPager->zJournal =   (char*)(pPtr += nPathname + 1);
     memcpy(pPager->zFilename, zPathname, nPathname);
     memcpy(pPager->zJournal, zPathname, nPathname);
     memcpy(&pPager->zJournal[nPathname], "-journal", 8);
-    if( pPager->zFilename[0]==0 ){
-      pPager->zJournal[0] = 0;
-    }
 #ifndef SQLITE_OMIT_WAL
-    else{
-      pPager->zWal = &pPager->zJournal[nPathname+8+1];
-      memcpy(pPager->zWal, zPathname, nPathname);
-      memcpy(&pPager->zWal[nPathname], "-wal", 4);
-    }
+    pPager->zWal = &pPager->zJournal[nPathname+8+1];
+    memcpy(pPager->zWal, zPathname, nPathname);
+    memcpy(&pPager->zWal[nPathname], "-wal", 4);
 #endif
     sqlite3_free(zPathname);
   }
@@ -37399,9 +38918,10 @@
 
   /* Open the pager file.
   */
-  if( zFilename && zFilename[0] && !memDb ){
+  if( zFilename && zFilename[0] ){
     int fout = 0;                    /* VFS flags returned by xOpen() */
     rc = sqlite3OsOpen(pVfs, pPager->zFilename, pPager->fd, vfsFlags, &fout);
+    assert( !memDb );
     readOnly = (fout&SQLITE_OPEN_READONLY);
 
     /* If the file was successfully opened for read/write access,
@@ -37419,7 +38939,7 @@
         if( pPager->sectorSize>SQLITE_MAX_DEFAULT_PAGE_SIZE ){
           szPageDflt = SQLITE_MAX_DEFAULT_PAGE_SIZE;
         }else{
-          szPageDflt = (u16)pPager->sectorSize;
+          szPageDflt = (u32)pPager->sectorSize;
         }
       }
 #ifdef SQLITE_ENABLE_ATOMIC_WRITE
@@ -37447,7 +38967,8 @@
     ** disk and uses an in-memory rollback journal.
     */ 
     tempFile = 1;
-    pPager->state = PAGER_EXCLUSIVE;
+    pPager->eState = PAGER_READER;
+    pPager->eLock = EXCLUSIVE_LOCK;
     readOnly = (vfsFlags&SQLITE_OPEN_READONLY);
   }
 
@@ -37484,13 +39005,14 @@
   /* pPager->stmtOpen = 0; */
   /* pPager->stmtInUse = 0; */
   /* pPager->nRef = 0; */
-  pPager->dbSizeValid = (u8)memDb;
   /* pPager->stmtSize = 0; */
   /* pPager->stmtJSize = 0; */
   /* pPager->nPage = 0; */
   pPager->mxPgno = SQLITE_MAX_PAGE_COUNT;
   /* pPager->state = PAGER_UNLOCK; */
+#if 0
   assert( pPager->state == (tempFile ? PAGER_EXCLUSIVE : PAGER_UNLOCK) );
+#endif
   /* pPager->errMask = 0; */
   pPager->tempFile = (u8)tempFile;
   assert( tempFile==PAGER_LOCKINGMODE_NORMAL 
@@ -37500,7 +39022,6 @@
   pPager->changeCountDone = pPager->tempFile;
   pPager->memDb = (u8)memDb;
   pPager->readOnly = (u8)readOnly;
-  /* pPager->needSync = 0; */
   assert( useJournal || pPager->tempFile );
   pPager->noSync = pPager->tempFile;
   pPager->fullSync = pPager->noSync ?0:1;
@@ -37565,10 +39086,10 @@
   int exists = 1;               /* True if a journal file is present */
   int jrnlOpen = !!isOpen(pPager->jfd);
 
-  assert( pPager!=0 );
   assert( pPager->useJournal );
   assert( isOpen(pPager->fd) );
-  assert( pPager->state <= PAGER_SHARED );
+  assert( pPager->eState==PAGER_OPEN );
+
   assert( jrnlOpen==0 || ( sqlite3OsDeviceCharacteristics(pPager->jfd) &
     SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN
   ));
@@ -37578,7 +39099,7 @@
     rc = sqlite3OsAccess(pVfs, pPager->zJournal, SQLITE_ACCESS_EXISTS, &exists);
   }
   if( rc==SQLITE_OK && exists ){
-    int locked;                 /* True if some process holds a RESERVED lock */
+    int locked = 0;             /* True if some process holds a RESERVED lock */
 
     /* Race condition here:  Another process might have been holding the
     ** the RESERVED lock and have a journal open at the sqlite3OsAccess() 
@@ -37590,7 +39111,7 @@
     */
     rc = sqlite3OsCheckReservedLock(pPager->fd, &locked);
     if( rc==SQLITE_OK && !locked ){
-      int nPage;
+      Pgno nPage;                 /* Number of pages in database file */
 
       /* Check the size of the database file. If it consists of 0 pages,
       ** then delete the journal file. See the header comment above for 
@@ -37598,13 +39119,13 @@
       ** a RESERVED lock to avoid race conditions and to avoid violating
       ** [H33020].
       */
-      rc = sqlite3PagerPagecount(pPager, &nPage);
+      rc = pagerPagecount(pPager, &nPage);
       if( rc==SQLITE_OK ){
         if( nPage==0 ){
           sqlite3BeginBenignMalloc();
-          if( sqlite3OsLock(pPager->fd, RESERVED_LOCK)==SQLITE_OK ){
+          if( pagerLockDb(pPager, RESERVED_LOCK)==SQLITE_OK ){
             sqlite3OsDelete(pVfs, pPager->zJournal, 0);
-            sqlite3OsUnlock(pPager->fd, SHARED_LOCK);
+            pagerUnlockDb(pPager, SHARED_LOCK);
           }
           sqlite3EndBenignMalloc();
         }else{
@@ -37657,7 +39178,7 @@
 **
 ** The following operations are also performed by this function.
 **
-**   1) If the pager is currently in PAGER_UNLOCK state (no lock held
+**   1) If the pager is currently in PAGER_OPEN state (no lock held
 **      on the database file), then an attempt is made to obtain a
 **      SHARED lock on the database file. Immediately after obtaining
 **      the SHARED lock, the file-system is checked for a hot-journal,
@@ -37672,66 +39193,47 @@
 **      the contents of the page cache and rolling back any open journal
 **      file.
 **
-** If the operation described by (2) above is not attempted, and if the
-** pager is in an error state other than SQLITE_FULL when this is called,
-** the error state error code is returned. It is permitted to read the
-** database when in SQLITE_FULL error state.
-**
-** Otherwise, if everything is successful, SQLITE_OK is returned. If an
-** IO error occurs while locking the database, checking for a hot-journal
-** file or rolling back a journal file, the IO error code is returned.
+** If everything is successful, SQLITE_OK is returned. If an IO error 
+** occurs while locking the database, checking for a hot-journal file or 
+** rolling back a journal file, the IO error code is returned.
 */
 SQLITE_PRIVATE int sqlite3PagerSharedLock(Pager *pPager){
   int rc = SQLITE_OK;                /* Return code */
-  int isErrorReset = 0;              /* True if recovering from error state */
 
   /* This routine is only called from b-tree and only when there are no
-  ** outstanding pages */
+  ** outstanding pages. This implies that the pager state should either
+  ** be OPEN or READER. READER is only possible if the pager is or was in 
+  ** exclusive access mode.
+  */
   assert( sqlite3PcacheRefCount(pPager->pPCache)==0 );
+  assert( assert_pager_state(pPager) );
+  assert( pPager->eState==PAGER_OPEN || pPager->eState==PAGER_READER );
   if( NEVER(MEMDB && pPager->errCode) ){ return pPager->errCode; }
 
-  /* If this database is in an error-state, now is a chance to clear
-  ** the error. Discard the contents of the pager-cache and rollback
-  ** any hot journal in the file-system.
-  */
-  if( pPager->errCode ){
-    if( isOpen(pPager->jfd) || pPager->zJournal ){
-      isErrorReset = 1;
-    }
-    pPager->errCode = SQLITE_OK;
-    pager_reset(pPager);
-  }
+  if( !pagerUseWal(pPager) && pPager->eState==PAGER_OPEN ){
+    int bHotJournal = 1;          /* True if there exists a hot journal-file */
 
-  if( pagerUseWal(pPager) ){
-    rc = pagerBeginReadTransaction(pPager);
-  }else if( pPager->state==PAGER_UNLOCK || isErrorReset ){
-    sqlite3_vfs * const pVfs = pPager->pVfs;
-    int isHotJournal = 0;
     assert( !MEMDB );
-    assert( sqlite3PcacheRefCount(pPager->pPCache)==0 );
-    if( pPager->noReadlock ){
-      assert( pPager->readOnly );
-      pPager->state = PAGER_SHARED;
-    }else{
+    assert( pPager->noReadlock==0 || pPager->readOnly );
+
+    if( pPager->noReadlock==0 ){
       rc = pager_wait_on_lock(pPager, SHARED_LOCK);
       if( rc!=SQLITE_OK ){
-        assert( pPager->state==PAGER_UNLOCK );
-        return pager_error(pPager, rc);
+        assert( pPager->eLock==NO_LOCK || pPager->eLock==UNKNOWN_LOCK );
+        goto failed;
       }
     }
-    assert( pPager->state>=SHARED_LOCK );
 
     /* If a journal file exists, and there is no RESERVED lock on the
     ** database file, then it either needs to be played back or deleted.
     */
-    if( !isErrorReset ){
-      assert( pPager->state <= PAGER_SHARED );
-      rc = hasHotJournal(pPager, &isHotJournal);
-      if( rc!=SQLITE_OK ){
-        goto failed;
-      }
+    if( pPager->eLock<=SHARED_LOCK ){
+      rc = hasHotJournal(pPager, &bHotJournal);
     }
-    if( isErrorReset || isHotJournal ){
+    if( rc!=SQLITE_OK ){
+      goto failed;
+    }
+    if( bHotJournal ){
       /* Get an EXCLUSIVE lock on the database file. At this point it is
       ** important that a RESERVED lock is not obtained on the way to the
       ** EXCLUSIVE lock. If it were, another process might open the
@@ -37743,58 +39245,45 @@
       ** other process attempting to access the database file will get to 
       ** this point in the code and fail to obtain its own EXCLUSIVE lock 
       ** on the database file.
+      **
+      ** Unless the pager is in locking_mode=exclusive mode, the lock is
+      ** downgraded to SHARED_LOCK before this function returns.
       */
-      if( pPager->state<EXCLUSIVE_LOCK ){
-        rc = sqlite3OsLock(pPager->fd, EXCLUSIVE_LOCK);
-        if( rc!=SQLITE_OK ){
-          rc = pager_error(pPager, rc);
-          goto failed;
-        }
-        pPager->state = PAGER_EXCLUSIVE;
-      }
- 
-      /* Open the journal for read/write access. This is because in 
-      ** exclusive-access mode the file descriptor will be kept open and
-      ** possibly used for a transaction later on. On some systems, the
-      ** OsTruncate() call used in exclusive-access mode also requires
-      ** a read/write file handle.
-      */
-      if( !isOpen(pPager->jfd) ){
-        int res;
-        rc = sqlite3OsAccess(pVfs,pPager->zJournal,SQLITE_ACCESS_EXISTS,&res);
-        if( rc==SQLITE_OK ){
-          if( res ){
-            int fout = 0;
-            int f = SQLITE_OPEN_READWRITE|SQLITE_OPEN_MAIN_JOURNAL;
-            assert( !pPager->tempFile );
-            rc = sqlite3OsOpen(pVfs, pPager->zJournal, pPager->jfd, f, &fout);
-            assert( rc!=SQLITE_OK || isOpen(pPager->jfd) );
-            if( rc==SQLITE_OK && fout&SQLITE_OPEN_READONLY ){
-              rc = SQLITE_CANTOPEN_BKPT;
-              sqlite3OsClose(pPager->jfd);
-            }
-          }else{
-            /* If the journal does not exist, it usually means that some 
-            ** other connection managed to get in and roll it back before 
-            ** this connection obtained the exclusive lock above. Or, it 
-            ** may mean that the pager was in the error-state when this
-            ** function was called and the journal file does not exist.  */
-            rc = pager_end_transaction(pPager, 0);
-          }
-        }
-      }
+      rc = pagerLockDb(pPager, EXCLUSIVE_LOCK);
       if( rc!=SQLITE_OK ){
         goto failed;
       }
-
-      /* Reset the journal status fields to indicates that we have no
-      ** rollback journal at this time. */
-      pPager->journalStarted = 0;
-      pPager->journalOff = 0;
-      pPager->setMaster = 0;
-      pPager->journalHdr = 0;
  
-      /* Make sure the journal file has been synced to disk. */
+      /* If it is not already open and the file exists on disk, open the 
+      ** journal for read/write access. Write access is required because 
+      ** in exclusive-access mode the file descriptor will be kept open 
+      ** and possibly used for a transaction later on. Also, write-access 
+      ** is usually required to finalize the journal in journal_mode=persist 
+      ** mode (and also for journal_mode=truncate on some systems).
+      **
+      ** If the journal does not exist, it usually means that some 
+      ** other connection managed to get in and roll it back before 
+      ** this connection obtained the exclusive lock above. Or, it 
+      ** may mean that the pager was in the error-state when this
+      ** function was called and the journal file does not exist.
+      */
+      if( !isOpen(pPager->jfd) ){
+        sqlite3_vfs * const pVfs = pPager->pVfs;
+        int bExists;              /* True if journal file exists */
+        rc = sqlite3OsAccess(
+            pVfs, pPager->zJournal, SQLITE_ACCESS_EXISTS, &bExists);
+        if( rc==SQLITE_OK && bExists ){
+          int fout = 0;
+          int f = SQLITE_OPEN_READWRITE|SQLITE_OPEN_MAIN_JOURNAL;
+          assert( !pPager->tempFile );
+          rc = sqlite3OsOpen(pVfs, pPager->zJournal, pPager->jfd, f, &fout);
+          assert( rc!=SQLITE_OK || isOpen(pPager->jfd) );
+          if( rc==SQLITE_OK && fout&SQLITE_OPEN_READONLY ){
+            rc = SQLITE_CANTOPEN_BKPT;
+            sqlite3OsClose(pPager->jfd);
+          }
+        }
+      }
  
       /* Playback and delete the journal.  Drop the database write
       ** lock and reacquire the read lock. Purge the cache before
@@ -37805,21 +39294,46 @@
       ** the journal before playing it back.
       */
       if( isOpen(pPager->jfd) ){
+        assert( rc==SQLITE_OK );
         rc = pagerSyncHotJournal(pPager);
         if( rc==SQLITE_OK ){
           rc = pager_playback(pPager, 1);
+          pPager->eState = PAGER_OPEN;
         }
-        if( rc!=SQLITE_OK ){
-          rc = pager_error(pPager, rc);
-          goto failed;
-        }
+      }else if( !pPager->exclusiveMode ){
+        pagerUnlockDb(pPager, SHARED_LOCK);
       }
-      assert( (pPager->state==PAGER_SHARED)
-           || (pPager->exclusiveMode && pPager->state>PAGER_SHARED)
+
+      if( rc!=SQLITE_OK ){
+        /* This branch is taken if an error occurs while trying to open
+        ** or roll back a hot-journal while holding an EXCLUSIVE lock. The
+        ** pager_unlock() routine will be called before returning to unlock
+        ** the file. If the unlock attempt fails, then Pager.eLock must be
+        ** set to UNKNOWN_LOCK (see the comment above the #define for 
+        ** UNKNOWN_LOCK above for an explanation). 
+        **
+        ** In order to get pager_unlock() to do this, set Pager.eState to
+        ** PAGER_ERROR now. This is not actually counted as a transition
+        ** to ERROR state in the state diagram at the top of this file,
+        ** since we know that the same call to pager_unlock() will very
+        ** shortly transition the pager object to the OPEN state. Calling
+        ** assert_pager_state() would fail now, as it should not be possible
+        ** to be in ERROR state when there are zero outstanding page 
+        ** references.
+        */
+        pager_error(pPager, rc);
+        goto failed;
+      }
+
+      assert( pPager->eState==PAGER_OPEN );
+      assert( (pPager->eLock==SHARED_LOCK)
+           || (pPager->exclusiveMode && pPager->eLock>SHARED_LOCK)
       );
     }
 
-    if( pPager->pBackup || sqlite3PcachePagecount(pPager->pPCache)>0 ){
+    if( !pPager->tempFile 
+     && (pPager->pBackup || sqlite3PcachePagecount(pPager->pPCache)>0) 
+    ){
       /* The shared-lock has just been acquired on the database file
       ** and there are already pages in the cache (from a previous
       ** read or write transaction).  Check to see if the database
@@ -37836,14 +39350,11 @@
       ** detected.  The chance of an undetected change is so small that
       ** it can be neglected.
       */
-      int nPage = 0;
+      Pgno nPage = 0;
       char dbFileVers[sizeof(pPager->dbFileVers)];
-      sqlite3PagerPagecount(pPager, &nPage);
 
-      if( pPager->errCode ){
-        rc = pPager->errCode;
-        goto failed;
-      }
+      rc = pagerPagecount(pPager, &nPage);
+      if( rc ) goto failed;
 
       if( nPage>0 ){
         IOTRACE(("CKVERS %p %d\n", pPager, sizeof(dbFileVers)));
@@ -37859,18 +39370,32 @@
         pager_reset(pPager);
       }
     }
-    assert( pPager->exclusiveMode || pPager->state==PAGER_SHARED );
 
     /* If there is a WAL file in the file-system, open this database in WAL
     ** mode. Otherwise, the following function call is a no-op.
     */
     rc = pagerOpenWalIfPresent(pPager);
+#ifndef SQLITE_OMIT_WAL
+    assert( pPager->pWal==0 || rc==SQLITE_OK );
+#endif
+  }
+
+  if( pagerUseWal(pPager) ){
+    assert( rc==SQLITE_OK );
+    rc = pagerBeginReadTransaction(pPager);
+  }
+
+  if( pPager->eState==PAGER_OPEN && rc==SQLITE_OK ){
+    rc = pagerPagecount(pPager, &pPager->dbSize);
   }
 
  failed:
   if( rc!=SQLITE_OK ){
-    /* pager_unlock() is a no-op for exclusive mode and in-memory databases. */
+    assert( !MEMDB );
     pager_unlock(pPager);
+    assert( pPager->eState==PAGER_OPEN );
+  }else{
+    pPager->eState = PAGER_READER;
   }
   return rc;
 }
@@ -37884,9 +39409,7 @@
 ** nothing to rollback, so this routine is a no-op.
 */ 
 static void pagerUnlockIfUnused(Pager *pPager){
-  if( (sqlite3PcacheRefCount(pPager->pPCache)==0)
-   && (!pPager->exclusiveMode || pPager->journalOff>0) 
-  ){
+  if( (sqlite3PcacheRefCount(pPager->pPCache)==0) ){
     pagerUnlockAndRollback(pPager);
   }
 }
@@ -37950,8 +39473,8 @@
   int rc;
   PgHdr *pPg;
 
+  assert( pPager->eState>=PAGER_READER );
   assert( assert_pager_state(pPager) );
-  assert( pPager->state>PAGER_UNLOCK );
 
   if( pgno==0 ){
     return SQLITE_CORRUPT_BKPT;
@@ -37959,7 +39482,7 @@
 
   /* If the pager is in the error state, return an error immediately. 
   ** Otherwise, request the page from the PCache layer. */
-  if( pPager->errCode!=SQLITE_OK && pPager->errCode!=SQLITE_FULL ){
+  if( pPager->errCode!=SQLITE_OK ){
     rc = pPager->errCode;
   }else{
     rc = sqlite3PcacheFetch(pPager->pPCache, pgno, 1, ppPage);
@@ -37985,7 +39508,6 @@
   }else{
     /* The pager cache has created a new page. Its content needs to 
     ** be initialized.  */
-    int nMax;
 
     PAGER_INCR(pPager->nMiss);
     pPg = *ppPage;
@@ -37998,12 +39520,7 @@
       goto pager_acquire_err;
     }
 
-    rc = sqlite3PagerPagecount(pPager, &nMax);
-    if( rc!=SQLITE_OK ){
-      goto pager_acquire_err;
-    }
-
-    if( MEMDB || nMax<(int)pgno || noContent || !isOpen(pPager->fd) ){
+    if( MEMDB || pPager->dbSize<pgno || noContent || !isOpen(pPager->fd) ){
       if( pgno>pPager->mxPgno ){
         rc = SQLITE_FULL;
         goto pager_acquire_err;
@@ -38033,9 +39550,7 @@
         goto pager_acquire_err;
       }
     }
-#ifdef SQLITE_CHECK_PAGES
-    pPg->pageHash = pager_pagehash(pPg);
-#endif
+    pager_set_pagehash(pPg);
   }
 
   return SQLITE_OK;
@@ -38054,9 +39569,7 @@
 /*
 ** Acquire a page if it is already in the in-memory cache.  Do
 ** not read the page from disk.  Return a pointer to the page,
-** or 0 if the page is not in cache. Also, return 0 if the 
-** pager is in PAGER_UNLOCK state when this function is called,
-** or if the pager is in an error state other than SQLITE_FULL.
+** or 0 if the page is not in cache. 
 **
 ** See also sqlite3PagerGet().  The difference between this routine
 ** and sqlite3PagerGet() is that _get() will go to the disk and read
@@ -38069,7 +39582,7 @@
   assert( pPager!=0 );
   assert( pgno!=0 );
   assert( pPager->pPCache!=0 );
-  assert( pPager->state > PAGER_UNLOCK );
+  assert( pPager->eState>=PAGER_READER && pPager->eState!=PAGER_ERROR );
   sqlite3PcacheFetch(pPager->pPCache, pgno, 0, &pPg);
   return pPg;
 }
@@ -38114,12 +39627,10 @@
 */
 static int pager_open_journal(Pager *pPager){
   int rc = SQLITE_OK;                        /* Return code */
-  int nPage;                                 /* Size of database file */
   sqlite3_vfs * const pVfs = pPager->pVfs;   /* Local cache of vfs pointer */
 
-  assert( pPager->state>=PAGER_RESERVED );
-  assert( pPager->useJournal );
-  assert( pPager->journalMode!=PAGER_JOURNALMODE_OFF );
+  assert( pPager->eState==PAGER_WRITER_LOCKED );
+  assert( assert_pager_state(pPager) );
   assert( pPager->pInJournal==0 );
   
   /* If already in the error state, this function is a no-op.  But on
@@ -38127,56 +39638,56 @@
   ** an error state. */
   if( NEVER(pPager->errCode) ) return pPager->errCode;
 
-  testcase( pPager->dbSizeValid==0 );
-  rc = sqlite3PagerPagecount(pPager, &nPage);
-  if( rc ) return rc;
-  pPager->pInJournal = sqlite3BitvecCreate(nPage);
-  if( pPager->pInJournal==0 ){
-    return SQLITE_NOMEM;
-  }
-
-  /* Open the journal file if it is not already open. */
-  if( !isOpen(pPager->jfd) ){
-    if( pPager->journalMode==PAGER_JOURNALMODE_MEMORY ){
-      sqlite3MemJournalOpen(pPager->jfd);
-    }else{
-      const int flags =                   /* VFS flags to open journal file */
-        SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE|
-        (pPager->tempFile ? 
-          (SQLITE_OPEN_DELETEONCLOSE|SQLITE_OPEN_TEMP_JOURNAL):
-          (SQLITE_OPEN_MAIN_JOURNAL)
-        );
-#ifdef SQLITE_ENABLE_ATOMIC_WRITE
-      rc = sqlite3JournalOpen(
-          pVfs, pPager->zJournal, pPager->jfd, flags, jrnlBufferSize(pPager)
-      );
-#else
-      rc = sqlite3OsOpen(pVfs, pPager->zJournal, pPager->jfd, flags, 0);
-#endif
+  if( !pagerUseWal(pPager) && pPager->journalMode!=PAGER_JOURNALMODE_OFF ){
+    pPager->pInJournal = sqlite3BitvecCreate(pPager->dbSize);
+    if( pPager->pInJournal==0 ){
+      return SQLITE_NOMEM;
     }
-    assert( rc!=SQLITE_OK || isOpen(pPager->jfd) );
-  }
-
-
-  /* Write the first journal header to the journal file and open 
-  ** the sub-journal if necessary.
-  */
-  if( rc==SQLITE_OK ){
-    /* TODO: Check if all of these are really required. */
-    pPager->dbOrigSize = pPager->dbSize;
-    pPager->journalStarted = 0;
-    pPager->needSync = 0;
-    pPager->nRec = 0;
-    pPager->journalOff = 0;
-    pPager->setMaster = 0;
-    pPager->journalHdr = 0;
-    rc = writeJournalHdr(pPager);
+  
+    /* Open the journal file if it is not already open. */
+    if( !isOpen(pPager->jfd) ){
+      if( pPager->journalMode==PAGER_JOURNALMODE_MEMORY ){
+        sqlite3MemJournalOpen(pPager->jfd);
+      }else{
+        const int flags =                   /* VFS flags to open journal file */
+          SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE|
+          (pPager->tempFile ? 
+            (SQLITE_OPEN_DELETEONCLOSE|SQLITE_OPEN_TEMP_JOURNAL):
+            (SQLITE_OPEN_MAIN_JOURNAL)
+          );
+  #ifdef SQLITE_ENABLE_ATOMIC_WRITE
+        rc = sqlite3JournalOpen(
+            pVfs, pPager->zJournal, pPager->jfd, flags, jrnlBufferSize(pPager)
+        );
+  #else
+        rc = sqlite3OsOpen(pVfs, pPager->zJournal, pPager->jfd, flags, 0);
+  #endif
+      }
+      assert( rc!=SQLITE_OK || isOpen(pPager->jfd) );
+    }
+  
+  
+    /* Write the first journal header to the journal file and open 
+    ** the sub-journal if necessary.
+    */
+    if( rc==SQLITE_OK ){
+      /* TODO: Check if all of these are really required. */
+      pPager->nRec = 0;
+      pPager->journalOff = 0;
+      pPager->setMaster = 0;
+      pPager->journalHdr = 0;
+      rc = writeJournalHdr(pPager);
+    }
   }
 
   if( rc!=SQLITE_OK ){
     sqlite3BitvecDestroy(pPager->pInJournal);
     pPager->pInJournal = 0;
+  }else{
+    assert( pPager->eState==PAGER_WRITER_LOCKED );
+    pPager->eState = PAGER_WRITER_CACHEMOD;
   }
+
   return rc;
 }
 
@@ -38189,14 +39700,6 @@
 ** an EXCLUSIVE lock. If such a lock is already held, no locking 
 ** functions need be called.
 **
-** If this is not a temporary or in-memory file and, the journal file is 
-** opened if it has not been already. For a temporary file, the opening 
-** of the journal file is deferred until there is an actual need to 
-** write to the journal. TODO: Why handle temporary files differently?
-**
-** If the journal file is opened (or if it is already open), then a
-** journal-header is written to the start of it.
-**
 ** If the subjInMemory argument is non-zero, then any sub-journal opened
 ** within this transaction will be opened as an in-memory file. This
 ** has no effect if the sub-journal is already opened (as it may be when
@@ -38207,20 +39710,20 @@
 */
 SQLITE_PRIVATE int sqlite3PagerBegin(Pager *pPager, int exFlag, int subjInMemory){
   int rc = SQLITE_OK;
-  assert( pPager->state!=PAGER_UNLOCK );
+
+  if( pPager->errCode ) return pPager->errCode;
+  assert( pPager->eState>=PAGER_READER && pPager->eState<PAGER_ERROR );
   pPager->subjInMemory = (u8)subjInMemory;
 
-  if( pPager->state==PAGER_SHARED ){
+  if( ALWAYS(pPager->eState==PAGER_READER) ){
     assert( pPager->pInJournal==0 );
-    assert( !MEMDB && !pPager->tempFile );
 
     if( pagerUseWal(pPager) ){
       /* If the pager is configured to use locking_mode=exclusive, and an
       ** exclusive lock on the database is not already held, obtain it now.
       */
       if( pPager->exclusiveMode && sqlite3WalExclusiveMode(pPager->pWal, -1) ){
-        rc = sqlite3OsLock(pPager->fd, EXCLUSIVE_LOCK);
-        pPager->state = PAGER_SHARED;
+        rc = pagerLockDb(pPager, EXCLUSIVE_LOCK);
         if( rc!=SQLITE_OK ){
           return rc;
         }
@@ -38231,52 +39734,40 @@
       ** PAGER_RESERVED state. Otherwise, return an error code to the caller.
       ** The busy-handler is not invoked if another connection already
       ** holds the write-lock. If possible, the upper layer will call it.
-      **
-      ** WAL mode sets Pager.state to PAGER_RESERVED when it has an open
-      ** transaction, but never to PAGER_EXCLUSIVE. This is because in 
-      ** PAGER_EXCLUSIVE state the code to roll back savepoint transactions
-      ** may copy data from the sub-journal into the database file as well
-      ** as into the page cache. Which would be incorrect in WAL mode.
       */
       rc = sqlite3WalBeginWriteTransaction(pPager->pWal);
-      if( rc==SQLITE_OK ){
-        pPager->dbOrigSize = pPager->dbSize;
-        pPager->state = PAGER_RESERVED;
-        pPager->journalOff = 0;
-      }
-
-      assert( rc!=SQLITE_OK || pPager->state==PAGER_RESERVED );
-      assert( rc==SQLITE_OK || pPager->state==PAGER_SHARED );
     }else{
       /* Obtain a RESERVED lock on the database file. If the exFlag parameter
       ** is true, then immediately upgrade this to an EXCLUSIVE lock. The
       ** busy-handler callback can be used when upgrading to the EXCLUSIVE
       ** lock, but not when obtaining the RESERVED lock.
       */
-      rc = sqlite3OsLock(pPager->fd, RESERVED_LOCK);
-      if( rc==SQLITE_OK ){
-        pPager->state = PAGER_RESERVED;
-        if( exFlag ){
-          rc = pager_wait_on_lock(pPager, EXCLUSIVE_LOCK);
-        }
+      rc = pagerLockDb(pPager, RESERVED_LOCK);
+      if( rc==SQLITE_OK && exFlag ){
+        rc = pager_wait_on_lock(pPager, EXCLUSIVE_LOCK);
       }
     }
 
-    /* No need to open the journal file at this time.  It will be
-    ** opened before it is written to.  If we defer opening the journal,
-    ** we might save the work of creating a file if the transaction
-    ** ends up being a no-op.
-    */
-
-    if( rc!=SQLITE_OK ){
-      assert( !pPager->dbModified );
-      /* Ignore any IO error that occurs within pager_end_transaction(). The
-      ** purpose of this call is to reset the internal state of the pager
-      ** sub-system. It doesn't matter if the journal-file is not properly
-      ** finalized at this point (since it is not a valid journal file anyway).
+    if( rc==SQLITE_OK ){
+      /* Change to WRITER_LOCKED state.
+      **
+      ** WAL mode sets Pager.eState to PAGER_WRITER_LOCKED or CACHEMOD
+      ** when it has an open transaction, but never to DBMOD or FINISHED.
+      ** This is because in those states the code to roll back savepoint 
+      ** transactions may copy data from the sub-journal into the database 
+      ** file as well as into the page cache. Which would be incorrect in 
+      ** WAL mode.
       */
-      pager_end_transaction(pPager, 0);
+      pPager->eState = PAGER_WRITER_LOCKED;
+      pPager->dbHintSize = pPager->dbSize;
+      pPager->dbFileSize = pPager->dbSize;
+      pPager->dbOrigSize = pPager->dbSize;
+      pPager->journalOff = 0;
     }
+
+    assert( rc==SQLITE_OK || pPager->eState==PAGER_READER );
+    assert( rc!=SQLITE_OK || pPager->eState==PAGER_WRITER_LOCKED );
+    assert( assert_pager_state(pPager) );
   }
 
   PAGERTRACE(("TRANSACTION %d\n", PAGERID(pPager)));
@@ -38295,22 +39786,24 @@
   Pager *pPager = pPg->pPager;
   int rc = SQLITE_OK;
 
-  /* This routine is not called unless a transaction has already been
-  ** started.
+  /* This routine is not called unless a write-transaction has already 
+  ** been started. The journal file may or may not be open at this point.
+  ** It is never called in the ERROR state.
   */
-  assert( pPager->state>=PAGER_RESERVED );
+  assert( pPager->eState==PAGER_WRITER_LOCKED
+       || pPager->eState==PAGER_WRITER_CACHEMOD
+       || pPager->eState==PAGER_WRITER_DBMOD
+  );
+  assert( assert_pager_state(pPager) );
 
   /* If an error has been previously detected, report the same error
-  ** again.
-  */
+  ** again. This should not happen, but the check provides robustness. */
   if( NEVER(pPager->errCode) )  return pPager->errCode;
 
   /* Higher-level routines never call this function if database is not
   ** writable.  But check anyway, just for robustness. */
   if( NEVER(pPager->readOnly) ) return SQLITE_PERM;
 
-  assert( !pPager->setMaster );
-
   CHECK_PAGE(pPg);
 
   /* Mark the page as dirty.  If the page has already been written
@@ -38319,56 +39812,60 @@
   sqlite3PcacheMakeDirty(pPg);
   if( pageInJournal(pPg) && !subjRequiresPage(pPg) ){
     assert( !pagerUseWal(pPager) );
-    pPager->dbModified = 1;
+    assert( pPager->eState>=PAGER_WRITER_CACHEMOD );
   }else{
 
     /* If we get this far, it means that the page needs to be
-    ** written to the transaction journal or the ckeckpoint journal
+    ** written to the transaction journal or the checkpoint journal
     ** or both.
     **
-    ** Higher level routines should have already started a transaction,
-    ** which means they have acquired the necessary locks but the rollback
-    ** journal might not yet be open.
+    ** Higher level routines have already obtained the necessary locks
+    ** to begin the write-transaction, but the rollback journal might not 
+    ** yet be open. Open it now if this is the case.
     */
-    assert( pPager->state>=RESERVED_LOCK );
-    if( pPager->pInJournal==0
-     && pPager->journalMode!=PAGER_JOURNALMODE_OFF 
-     && !pagerUseWal(pPager)
-    ){
-      assert( pPager->useJournal );
+    if( pPager->eState==PAGER_WRITER_LOCKED ){
       rc = pager_open_journal(pPager);
       if( rc!=SQLITE_OK ) return rc;
     }
-    pPager->dbModified = 1;
+    assert( pPager->eState>=PAGER_WRITER_CACHEMOD );
+    assert( assert_pager_state(pPager) );
   
     /* The transaction journal now exists and we have a RESERVED or an
     ** EXCLUSIVE lock on the main database file.  Write the current page to
     ** the transaction journal if it is not there already.
     */
-    if( !pageInJournal(pPg) && isOpen(pPager->jfd) ){
-      assert( !pagerUseWal(pPager) );
-      if( pPg->pgno<=pPager->dbOrigSize ){
+    if( !pageInJournal(pPg) && !pagerUseWal(pPager) ){
+      assert( pagerUseWal(pPager)==0 );
+      if( pPg->pgno<=pPager->dbOrigSize && isOpen(pPager->jfd) ){
         u32 cksum;
         char *pData2;
+        i64 iOff = pPager->journalOff;
 
         /* We should never write to the journal file the page that
         ** contains the database locks.  The following assert verifies
         ** that we do not. */
         assert( pPg->pgno!=PAGER_MJ_PGNO(pPager) );
 
-        assert( pPager->journalHdr <= pPager->journalOff );
+        assert( pPager->journalHdr<=pPager->journalOff );
         CODEC2(pPager, pData, pPg->pgno, 7, return SQLITE_NOMEM, pData2);
         cksum = pager_cksum(pPager, (u8*)pData2);
-        rc = write32bits(pPager->jfd, pPager->journalOff, pPg->pgno);
-        if( rc==SQLITE_OK ){
-          rc = sqlite3OsWrite(pPager->jfd, pData2, pPager->pageSize,
-                              pPager->journalOff + 4);
-          pPager->journalOff += pPager->pageSize+4;
-        }
-        if( rc==SQLITE_OK ){
-          rc = write32bits(pPager->jfd, pPager->journalOff, cksum);
-          pPager->journalOff += 4;
-        }
+
+        /* Even if an IO or diskfull error occurs while journalling the
+        ** page in the block above, set the need-sync flag for the page.
+        ** Otherwise, when the transaction is rolled back, the logic in
+        ** playback_one_page() will think that the page needs to be restored
+        ** in the database file. And if an IO error occurs while doing so,
+        ** then corruption may follow.
+        */
+        pPg->flags |= PGHDR_NEED_SYNC;
+
+        rc = write32bits(pPager->jfd, iOff, pPg->pgno);
+        if( rc!=SQLITE_OK ) return rc;
+        rc = sqlite3OsWrite(pPager->jfd, pData2, pPager->pageSize, iOff+4);
+        if( rc!=SQLITE_OK ) return rc;
+        rc = write32bits(pPager->jfd, iOff+pPager->pageSize+4, cksum);
+        if( rc!=SQLITE_OK ) return rc;
+
         IOTRACE(("JOUT %p %d %lld %d\n", pPager, pPg->pgno, 
                  pPager->journalOff, pPager->pageSize));
         PAGER_INCR(sqlite3_pager_writej_count);
@@ -38376,25 +39873,7 @@
              PAGERID(pPager), pPg->pgno, 
              ((pPg->flags&PGHDR_NEED_SYNC)?1:0), pager_pagehash(pPg)));
 
-        /* Even if an IO or diskfull error occurred while journalling the
-        ** page in the block above, set the need-sync flag for the page.
-        ** Otherwise, when the transaction is rolled back, the logic in
-        ** playback_one_page() will think that the page needs to be restored
-        ** in the database file. And if an IO error occurs while doing so,
-        ** then corruption may follow.
-        */
-        if( !pPager->noSync ){
-          pPg->flags |= PGHDR_NEED_SYNC;
-          pPager->needSync = 1;
-        }
-
-        /* An error has occurred writing to the journal file. The 
-        ** transaction will be rolled back by the layer above.
-        */
-        if( rc!=SQLITE_OK ){
-          return rc;
-        }
-
+        pPager->journalOff += 8 + pPager->pageSize;
         pPager->nRec++;
         assert( pPager->pInJournal!=0 );
         rc = sqlite3BitvecSet(pPager->pInJournal, pPg->pgno);
@@ -38406,9 +39885,8 @@
           return rc;
         }
       }else{
-        if( !pPager->journalStarted && !pPager->noSync ){
+        if( pPager->eState!=PAGER_WRITER_DBMOD ){
           pPg->flags |= PGHDR_NEED_SYNC;
-          pPager->needSync = 1;
         }
         PAGERTRACE(("APPEND %d page %d needSync=%d\n",
                 PAGERID(pPager), pPg->pgno,
@@ -38428,7 +39906,6 @@
 
   /* Update the database size and return.
   */
-  assert( pPager->state>=PAGER_SHARED );
   if( pPager->dbSize<pPg->pgno ){
     pPager->dbSize = pPg->pgno;
   }
@@ -38456,6 +39933,10 @@
   Pager *pPager = pPg->pPager;
   Pgno nPagePerSector = (pPager->sectorSize/pPager->pageSize);
 
+  assert( pPager->eState>=PAGER_WRITER_LOCKED );
+  assert( pPager->eState!=PAGER_ERROR );
+  assert( assert_pager_state(pPager) );
+
   if( nPagePerSector>1 ){
     Pgno nPageCount;          /* Total number of pages in database file */
     Pgno pg1;                 /* First page of the sector pPg is located on. */
@@ -38477,19 +39958,17 @@
     */
     pg1 = ((pPg->pgno-1) & ~(nPagePerSector-1)) + 1;
 
-    rc = sqlite3PagerPagecount(pPager, (int *)&nPageCount);
-    if( rc==SQLITE_OK ){
-      if( pPg->pgno>nPageCount ){
-        nPage = (pPg->pgno - pg1)+1;
-      }else if( (pg1+nPagePerSector-1)>nPageCount ){
-        nPage = nPageCount+1-pg1;
-      }else{
-        nPage = nPagePerSector;
-      }
-      assert(nPage>0);
-      assert(pg1<=pPg->pgno);
-      assert((pg1+nPage)>pPg->pgno);
+    nPageCount = pPager->dbSize;
+    if( pPg->pgno>nPageCount ){
+      nPage = (pPg->pgno - pg1)+1;
+    }else if( (pg1+nPagePerSector-1)>nPageCount ){
+      nPage = nPageCount+1-pg1;
+    }else{
+      nPage = nPagePerSector;
     }
+    assert(nPage>0);
+    assert(pg1<=pPg->pgno);
+    assert((pg1+nPage)>pPg->pgno);
 
     for(ii=0; ii<nPage && rc==SQLITE_OK; ii++){
       Pgno pg = pg1+ii;
@@ -38501,7 +39980,6 @@
             rc = pager_write(pPage);
             if( pPage->flags&PGHDR_NEED_SYNC ){
               needSync = 1;
-              assert(pPager->needSync);
             }
             sqlite3PagerUnref(pPage);
           }
@@ -38521,7 +39999,7 @@
     ** before any of them can be written out to the database file.
     */
     if( rc==SQLITE_OK && needSync ){
-      assert( !MEMDB && pPager->noSync==0 );
+      assert( !MEMDB );
       for(ii=0; ii<nPage; ii++){
         PgHdr *pPage = pager_lookup(pPager, pg1+ii);
         if( pPage ){
@@ -38529,7 +40007,6 @@
           sqlite3PagerUnref(pPage);
         }
       }
-      assert(pPager->needSync);
     }
 
     assert( pPager->doNotSyncSpill==1 );
@@ -38571,9 +40048,7 @@
     PAGERTRACE(("DONT_WRITE page %d of %d\n", pPg->pgno, PAGERID(pPager)));
     IOTRACE(("CLEAN %p %d\n", pPager, pPg->pgno))
     pPg->flags |= PGHDR_DONT_WRITE;
-#ifdef SQLITE_CHECK_PAGES
-    pPg->pageHash = pager_pagehash(pPg);
-#endif
+    pager_set_pagehash(pPg);
   }
 }
 
@@ -38596,6 +40071,11 @@
 static int pager_incr_changecounter(Pager *pPager, int isDirectMode){
   int rc = SQLITE_OK;
 
+  assert( pPager->eState==PAGER_WRITER_CACHEMOD
+       || pPager->eState==PAGER_WRITER_DBMOD
+  );
+  assert( assert_pager_state(pPager) );
+
   /* Declare and initialize constant integer 'isDirect'. If the
   ** atomic-write optimization is enabled in this build, then isDirect
   ** is initialized to the value passed as the isDirectMode parameter
@@ -38614,7 +40094,6 @@
 # define DIRECT_MODE isDirectMode
 #endif
 
-  assert( pPager->state>=PAGER_RESERVED );
   if( !pPager->changeCountDone && pPager->dbSize>0 ){
     PgHdr *pPgHdr;                /* Reference to page 1 */
     u32 change_counter;           /* Initial value of change-counter field */
@@ -38687,6 +40166,30 @@
 }
 
 /*
+** This function may only be called while a write-transaction is active in
+** rollback. If the connection is in WAL mode, this call is a no-op. 
+** Otherwise, if the connection does not already have an EXCLUSIVE lock on 
+** the database file, an attempt is made to obtain one.
+**
+** If the EXCLUSIVE lock is already held or the attempt to obtain it is
+** successful, or the connection is in WAL mode, SQLITE_OK is returned.
+** Otherwise, either SQLITE_BUSY or an SQLITE_IOERR_XXX error code is 
+** returned.
+*/
+SQLITE_PRIVATE int sqlite3PagerExclusiveLock(Pager *pPager){
+  int rc = SQLITE_OK;
+  assert( pPager->eState==PAGER_WRITER_CACHEMOD 
+       || pPager->eState==PAGER_WRITER_DBMOD 
+       || pPager->eState==PAGER_WRITER_LOCKED 
+  );
+  assert( assert_pager_state(pPager) );
+  if( 0==pagerUseWal(pPager) ){
+    rc = pager_wait_on_lock(pPager, EXCLUSIVE_LOCK);
+  }
+  return rc;
+}
+
+/*
 ** Sync the database file for the pager pPager. zMaster points to the name
 ** of a master journal file that should be written into the individual
 ** journal file. zMaster may be NULL, which is interpreted as no master
@@ -38719,22 +40222,29 @@
 ){
   int rc = SQLITE_OK;             /* Return code */
 
-  /* The dbOrigSize is never set if journal_mode=OFF */
-  assert( pPager->journalMode!=PAGER_JOURNALMODE_OFF || pPager->dbOrigSize==0 );
+  assert( pPager->eState==PAGER_WRITER_LOCKED
+       || pPager->eState==PAGER_WRITER_CACHEMOD
+       || pPager->eState==PAGER_WRITER_DBMOD
+       || pPager->eState==PAGER_ERROR
+  );
+  assert( assert_pager_state(pPager) );
 
   /* If a prior error occurred, report that error again. */
-  if( pPager->errCode ) return pPager->errCode;
+  if( NEVER(pPager->errCode) ) return pPager->errCode;
 
   PAGERTRACE(("DATABASE SYNC: File=%s zMaster=%s nSize=%d\n", 
       pPager->zFilename, zMaster, pPager->dbSize));
 
-  if( MEMDB && pPager->dbModified ){
+  /* If no database changes have been made, return early. */
+  if( pPager->eState<PAGER_WRITER_CACHEMOD ) return SQLITE_OK;
+
+  if( MEMDB ){
     /* If this is an in-memory db, or no pages have been written to, or this
     ** function has already been called, it is mostly a no-op.  However, any
     ** backup in progress needs to be restarted.
     */
     sqlite3BackupRestart(pPager->pBackup);
-  }else if( pPager->state!=PAGER_SYNCED && pPager->dbModified ){
+  }else{
     if( pagerUseWal(pPager) ){
       PgHdr *pList = sqlite3PcacheDirtyList(pPager->pPCache);
       if( pList ){
@@ -38777,7 +40287,7 @@
       );
       if( !zMaster && isOpen(pPager->jfd) 
        && pPager->journalOff==jrnlBufferSize(pPager) 
-       && pPager->dbSize>=pPager->dbFileSize
+       && pPager->dbSize>=pPager->dbOrigSize
        && (0==(pPg = sqlite3PcacheDirtyList(pPager->pPCache)) || 0==pPg->pDirty)
       ){
         /* Update the db file change counter via the direct-write method. The 
@@ -38807,13 +40317,10 @@
       ** that it took at the start of the transaction. Otherwise, the
       ** calls to sqlite3PagerGet() return zeroed pages instead of 
       ** reading data from the database file.
-      **
-      ** When journal_mode==OFF the dbOrigSize is always zero, so this
-      ** block never runs if journal_mode=OFF.
       */
   #ifndef SQLITE_OMIT_AUTOVACUUM
       if( pPager->dbSize<pPager->dbOrigSize 
-       && ALWAYS(pPager->journalMode!=PAGER_JOURNALMODE_OFF)
+       && pPager->journalMode!=PAGER_JOURNALMODE_OFF
       ){
         Pgno i;                                   /* Iterator variable */
         const Pgno iSkip = PAGER_MJ_PGNO(pPager); /* Pending lock page */
@@ -38840,14 +40347,20 @@
       rc = writeMasterJournal(pPager, zMaster);
       if( rc!=SQLITE_OK ) goto commit_phase_one_exit;
   
-      /* Sync the journal file. If the atomic-update optimization is being
-      ** used, this call will not create the journal file or perform any
-      ** real IO.
+      /* Sync the journal file and write all dirty pages to the database.
+      ** If the atomic-update optimization is being used, this sync will not 
+      ** create the journal file or perform any real IO.
+      **
+      ** Because the change-counter page was just modified, unless the
+      ** atomic-update optimization is used it is almost certain that the
+      ** journal requires a sync here. However, in locking_mode=exclusive
+      ** on a system under memory pressure it is just possible that this is 
+      ** not the case. In this case it is likely enough that the redundant
+      ** xSync() call will be changed to a no-op by the OS anyhow. 
       */
-      rc = syncJournal(pPager);
+      rc = syncJournal(pPager, 0);
       if( rc!=SQLITE_OK ) goto commit_phase_one_exit;
   
-      /* Write all dirty pages to the database file. */
       rc = pager_write_pagelist(pPager,sqlite3PcacheDirtyList(pPager->pPCache));
       if( rc!=SQLITE_OK ){
         assert( rc!=SQLITE_IOERR_BLOCKED );
@@ -38860,7 +40373,7 @@
       */
       if( pPager->dbSize!=pPager->dbFileSize ){
         Pgno nNew = pPager->dbSize - (pPager->dbSize==PAGER_MJ_PGNO(pPager));
-        assert( pPager->state>=PAGER_EXCLUSIVE );
+        assert( pPager->eState==PAGER_WRITER_DBMOD );
         rc = pager_truncate(pPager, nNew);
         if( rc!=SQLITE_OK ) goto commit_phase_one_exit;
       }
@@ -38871,11 +40384,12 @@
       }
       IOTRACE(("DBSYNC %p\n", pPager))
     }
-
-    pPager->state = PAGER_SYNCED;
   }
 
 commit_phase_one_exit:
+  if( rc==SQLITE_OK && !pagerUseWal(pPager) ){
+    pPager->eState = PAGER_WRITER_FINISHED;
+  }
   return rc;
 }
 
@@ -38903,12 +40417,11 @@
   ** called, just return the same error code without doing anything. */
   if( NEVER(pPager->errCode) ) return pPager->errCode;
 
-  /* This function should not be called if the pager is not in at least
-  ** PAGER_RESERVED state. **FIXME**: Make it so that this test always
-  ** fails - make it so that we never reach this point if we do not hold
-  ** all necessary locks.
-  */
-  if( NEVER(pPager->state<PAGER_RESERVED) ) return SQLITE_ERROR;
+  assert( pPager->eState==PAGER_WRITER_LOCKED
+       || pPager->eState==PAGER_WRITER_FINISHED
+       || (pagerUseWal(pPager) && pPager->eState==PAGER_WRITER_CACHEMOD)
+  );
+  assert( assert_pager_state(pPager) );
 
   /* An optimization. If the database was not actually modified during
   ** this transaction, the pager is running in exclusive-mode and is
@@ -38921,102 +40434,76 @@
   ** header. Since the pager is in exclusive mode, there is no need
   ** to drop any locks either.
   */
-  if( pPager->dbModified==0 && pPager->exclusiveMode 
+  if( pPager->eState==PAGER_WRITER_LOCKED 
+   && pPager->exclusiveMode 
    && pPager->journalMode==PAGER_JOURNALMODE_PERSIST
   ){
     assert( pPager->journalOff==JOURNAL_HDR_SZ(pPager) || !pPager->journalOff );
+    pPager->eState = PAGER_READER;
     return SQLITE_OK;
   }
 
   PAGERTRACE(("COMMIT %d\n", PAGERID(pPager)));
-  assert( pPager->state==PAGER_SYNCED || MEMDB || !pPager->dbModified );
   rc = pager_end_transaction(pPager, pPager->setMaster);
   return pager_error(pPager, rc);
 }
 
 /*
-** Rollback all changes. The database falls back to PAGER_SHARED mode.
+** If a write transaction is open, then all changes made within the 
+** transaction are reverted and the current write-transaction is closed.
+** The pager falls back to PAGER_READER state if successful, or PAGER_ERROR
+** state if an error occurs.
 **
-** This function performs two tasks:
+** If the pager is already in PAGER_ERROR state when this function is called,
+** it returns Pager.errCode immediately. No work is performed in this case.
+**
+** Otherwise, in rollback mode, this function performs two functions:
 **
 **   1) It rolls back the journal file, restoring all database file and 
 **      in-memory cache pages to the state they were in when the transaction
 **      was opened, and
+**
 **   2) It finalizes the journal file, so that it is not used for hot
 **      rollback at any point in the future.
 **
-** subject to the following qualifications:
+** Finalization of the journal file (task 2) is only performed if the 
+** rollback is successful.
 **
-** * If the journal file is not yet open when this function is called,
-**   then only (2) is performed. In this case there is no journal file
-**   to roll back.
-**
-** * If in an error state other than SQLITE_FULL, then task (1) is 
-**   performed. If successful, task (2). Regardless of the outcome
-**   of either, the error state error code is returned to the caller
-**   (i.e. either SQLITE_IOERR or SQLITE_CORRUPT).
-**
-** * If the pager is in PAGER_RESERVED state, then attempt (1). Whether
-**   or not (1) is successful, also attempt (2). If successful, return
-**   SQLITE_OK. Otherwise, enter the error state and return the first 
-**   error code encountered. 
-**
-**   In this case there is no chance that the database was written to. 
-**   So is safe to finalize the journal file even if the playback 
-**   (operation 1) failed. However the pager must enter the error state
-**   as the contents of the in-memory cache are now suspect.
-**
-** * Finally, if in PAGER_EXCLUSIVE state, then attempt (1). Only
-**   attempt (2) if (1) is successful. Return SQLITE_OK if successful,
-**   otherwise enter the error state and return the error code from the 
-**   failing operation.
-**
-**   In this case the database file may have been written to. So if the
-**   playback operation did not succeed it would not be safe to finalize
-**   the journal file. It needs to be left in the file-system so that
-**   some other process can use it to restore the database state (by
-**   hot-journal rollback).
+** In WAL mode, all cache-entries containing data modified within the
+** current transaction are either expelled from the cache or reverted to
+** their pre-transaction state by re-reading data from the database or
+** WAL files. The WAL transaction is then closed.
 */
 SQLITE_PRIVATE int sqlite3PagerRollback(Pager *pPager){
   int rc = SQLITE_OK;                  /* Return code */
   PAGERTRACE(("ROLLBACK %d\n", PAGERID(pPager)));
+
+  /* PagerRollback() is a no-op if called in READER or OPEN state. If
+  ** the pager is already in the ERROR state, the rollback is not 
+  ** attempted here. Instead, the error code is returned to the caller.
+  */
+  assert( assert_pager_state(pPager) );
+  if( pPager->eState==PAGER_ERROR ) return pPager->errCode;
+  if( pPager->eState<=PAGER_READER ) return SQLITE_OK;
+
   if( pagerUseWal(pPager) ){
     int rc2;
-
     rc = sqlite3PagerSavepoint(pPager, SAVEPOINT_ROLLBACK, -1);
     rc2 = pager_end_transaction(pPager, pPager->setMaster);
     if( rc==SQLITE_OK ) rc = rc2;
-    rc = pager_error(pPager, rc);
-  }else if( !pPager->dbModified || !isOpen(pPager->jfd) ){
-    rc = pager_end_transaction(pPager, pPager->setMaster);
-  }else if( pPager->errCode && pPager->errCode!=SQLITE_FULL ){
-    if( pPager->state>=PAGER_EXCLUSIVE ){
-      pager_playback(pPager, 0);
-    }
-    rc = pPager->errCode;
+  }else if( !isOpen(pPager->jfd) || pPager->eState==PAGER_WRITER_LOCKED ){
+    rc = pager_end_transaction(pPager, 0);
   }else{
-    if( pPager->state==PAGER_RESERVED ){
-      int rc2;
-      rc = pager_playback(pPager, 0);
-      rc2 = pager_end_transaction(pPager, pPager->setMaster);
-      if( rc==SQLITE_OK ){
-        rc = rc2;
-      }
-    }else{
-      rc = pager_playback(pPager, 0);
-    }
-
-    if( !MEMDB ){
-      pPager->dbSizeValid = 0;
-    }
-
-    /* If an error occurs during a ROLLBACK, we can no longer trust the pager
-    ** cache. So call pager_error() on the way out to make any error 
-    ** persistent.
-    */
-    rc = pager_error(pPager, rc);
+    rc = pager_playback(pPager, 0);
   }
-  return rc;
+
+  assert( pPager->eState==PAGER_READER || rc!=SQLITE_OK );
+  assert( rc==SQLITE_OK || rc==SQLITE_FULL || (rc&0xFF)==SQLITE_IOERR );
+
+  /* If an error occurs during a ROLLBACK, we can no longer trust the pager
+  ** cache. So call pager_error() on the way out to make any error persistent.
+  */
+  return pager_error(pPager, rc);
 }
 
 /*
@@ -39039,9 +40526,11 @@
 ** used by the pager and its associated cache.
 */
 SQLITE_PRIVATE int sqlite3PagerMemUsed(Pager *pPager){
-  int perPageSize = pPager->pageSize + pPager->nExtra + 20;
+  int perPageSize = pPager->pageSize + pPager->nExtra + sizeof(PgHdr)
+                                     + 5*sizeof(void*);
   return perPageSize*sqlite3PcachePagecount(pPager->pPCache)
-           + sqlite3MallocSize(pPager);
+           + sqlite3MallocSize(pPager)
+           + pPager->pageSize;
 }
 
 /*
@@ -39060,8 +40549,8 @@
   a[0] = sqlite3PcacheRefCount(pPager->pPCache);
   a[1] = sqlite3PcachePagecount(pPager->pPCache);
   a[2] = sqlite3PcacheGetCachesize(pPager->pPCache);
-  a[3] = pPager->dbSizeValid ? (int) pPager->dbSize : -1;
-  a[4] = pPager->state;
+  a[3] = pPager->eState==PAGER_OPEN ? -1 : (int) pPager->dbSize;
+  a[4] = pPager->eState;
   a[5] = pPager->errCode;
   a[6] = pPager->nHit;
   a[7] = pPager->nMiss;
@@ -39093,13 +40582,12 @@
   int rc = SQLITE_OK;                       /* Return code */
   int nCurrent = pPager->nSavepoint;        /* Current number of savepoints */
 
+  assert( pPager->eState>=PAGER_WRITER_LOCKED );
+  assert( assert_pager_state(pPager) );
+
   if( nSavepoint>nCurrent && pPager->useJournal ){
     int ii;                                 /* Iterator variable */
     PagerSavepoint *aNew;                   /* New Pager.aSavepoint array */
-    int nPage;                              /* Size of database file */
-
-    rc = sqlite3PagerPagecount(pPager, &nPage);
-    if( rc ) return rc;
 
     /* Grow the Pager.aSavepoint array using realloc(). Return SQLITE_NOMEM
     ** if the allocation fails. Otherwise, zero the new portion in case a 
@@ -39116,14 +40604,14 @@
 
     /* Populate the PagerSavepoint structures just allocated. */
     for(ii=nCurrent; ii<nSavepoint; ii++){
-      aNew[ii].nOrig = nPage;
+      aNew[ii].nOrig = pPager->dbSize;
       if( isOpen(pPager->jfd) && pPager->journalOff>0 ){
         aNew[ii].iOffset = pPager->journalOff;
       }else{
         aNew[ii].iOffset = JOURNAL_HDR_SZ(pPager);
       }
       aNew[ii].iSubRec = pPager->nSubRec;
-      aNew[ii].pInSavepoint = sqlite3BitvecCreate(nPage);
+      aNew[ii].pInSavepoint = sqlite3BitvecCreate(pPager->dbSize);
       if( !aNew[ii].pInSavepoint ){
         return SQLITE_NOMEM;
       }
@@ -39170,12 +40658,12 @@
 ** savepoint. If no errors occur, SQLITE_OK is returned.
 */ 
 SQLITE_PRIVATE int sqlite3PagerSavepoint(Pager *pPager, int op, int iSavepoint){
-  int rc = SQLITE_OK;
+  int rc = pPager->errCode;       /* Return code */
 
   assert( op==SAVEPOINT_RELEASE || op==SAVEPOINT_ROLLBACK );
   assert( iSavepoint>=0 || op==SAVEPOINT_ROLLBACK );
 
-  if( iSavepoint<pPager->nSavepoint ){
+  if( rc==SQLITE_OK && iSavepoint<pPager->nSavepoint ){
     int ii;            /* Iterator variable */
     int nNew;          /* Number of remaining savepoints after this op. */
 
@@ -39211,8 +40699,8 @@
       rc = pagerPlaybackSavepoint(pPager, pSavepoint);
       assert(rc!=SQLITE_DONE);
     }
-  
   }
+
   return rc;
 }
 
@@ -39310,6 +40798,10 @@
   Pgno origPgno;               /* The original page number */
 
   assert( pPg->nRef>0 );
+  assert( pPager->eState==PAGER_WRITER_CACHEMOD
+       || pPager->eState==PAGER_WRITER_DBMOD
+  );
+  assert( assert_pager_state(pPager) );
 
   /* In order to be able to rollback, an in-memory database must journal
   ** the page we are moving from.
@@ -39359,11 +40851,10 @@
     needSyncPgno = pPg->pgno;
     assert( pageInJournal(pPg) || pPg->pgno>pPager->dbOrigSize );
     assert( pPg->flags&PGHDR_DIRTY );
-    assert( pPager->needSync );
   }
 
   /* If the cache contains a page with page-number pgno, remove it
-  ** from its hash chain. Also, if the PgHdr.needSync was set for 
+  ** from its hash chain. Also, if the PGHDR_NEED_SYNC flag was set for 
   ** page pgno before the 'move' operation, it needs to be retained 
   ** for the page moved there.
   */
@@ -39375,7 +40866,6 @@
     if( MEMDB ){
       /* Do not discard pages from an in-memory database since we might
       ** need to rollback later.  Just move the page out of the way. */
-      assert( pPager->dbSizeValid );
       sqlite3PcacheMove(pPgOld, pPager->dbSize+1);
     }else{
       sqlite3PcacheDrop(pPgOld);
@@ -39385,14 +40875,23 @@
   origPgno = pPg->pgno;
   sqlite3PcacheMove(pPg, pgno);
   sqlite3PcacheMakeDirty(pPg);
-  pPager->dbModified = 1;
+
+  /* For an in-memory database, make sure the original page continues
+  ** to exist, in case the transaction needs to roll back.  Use pPgOld
+  ** as the original page since it has already been allocated.
+  */
+  if( MEMDB ){
+    assert( pPgOld );
+    sqlite3PcacheMove(pPgOld, origPgno);
+    sqlite3PagerUnref(pPgOld);
+  }
 
   if( needSyncPgno ){
     /* If needSyncPgno is non-zero, then the journal file needs to be 
     ** sync()ed before any data is written to database file page needSyncPgno.
     ** Currently, no such page exists in the page-cache and the 
     ** "is journaled" bitvec flag has been set. This needs to be remedied by
-    ** loading the page into the pager-cache and setting the PgHdr.needSync 
+    ** loading the page into the pager-cache and setting the PGHDR_NEED_SYNC
     ** flag.
     **
     ** If the attempt to load the page into the page-cache fails, (due
@@ -39401,12 +40900,8 @@
     ** this transaction, it may be written to the database file before
     ** it is synced into the journal file. This way, it may end up in
     ** the journal file twice, but that is not a problem.
-    **
-    ** The sqlite3PagerGet() call may cause the journal to sync. So make
-    ** sure the Pager.needSync flag is set too.
     */
     PgHdr *pPgHdr;
-    assert( pPager->needSync );
     rc = sqlite3PagerGet(pPager, needSyncPgno, &pPgHdr);
     if( rc!=SQLITE_OK ){
       if( needSyncPgno<=pPager->dbOrigSize ){
@@ -39415,23 +40910,11 @@
       }
       return rc;
     }
-    pPager->needSync = 1;
-    assert( pPager->noSync==0 && !MEMDB );
     pPgHdr->flags |= PGHDR_NEED_SYNC;
     sqlite3PcacheMakeDirty(pPgHdr);
     sqlite3PagerUnref(pPgHdr);
   }
 
-  /*
-  ** For an in-memory database, make sure the original page continues
-  ** to exist, in case the transaction needs to roll back.  Use pPgOld
-  ** as the original page since it has already been allocated.
-  */
-  if( MEMDB ){
-    sqlite3PcacheMove(pPgOld, origPgno);
-    sqlite3PagerUnref(pPgOld);
-  }
-
   return SQLITE_OK;
 }
 #endif
@@ -39497,6 +40980,13 @@
 SQLITE_PRIVATE int sqlite3PagerSetJournalMode(Pager *pPager, int eMode){
   u8 eOld = pPager->journalMode;    /* Prior journalmode */
 
+#ifdef SQLITE_DEBUG
+  /* The print_pager_state() routine is intended to be used by the debugger
+  ** only.  We invoke it once here to suppress a compiler warning. */
+  print_pager_state(pPager);
+#endif
+
+
   /* The eMode parameter is always valid */
   assert(      eMode==PAGER_JOURNALMODE_DELETE
             || eMode==PAGER_JOURNALMODE_TRUNCATE
@@ -39505,12 +40995,11 @@
             || eMode==PAGER_JOURNALMODE_WAL 
             || eMode==PAGER_JOURNALMODE_MEMORY );
 
-  /* Do not allow the journalmode of a TEMP database to be changed to WAL
+  /* This routine is only called from the OP_JournalMode opcode, and
+  ** the logic there will never allow a temporary file to be changed
+  ** to WAL mode.
   */
-  if( pPager->tempFile && eMode==PAGER_JOURNALMODE_WAL ){
-    assert( eOld!=PAGER_JOURNALMODE_WAL );
-    eMode = eOld;
-  }
+  assert( pPager->tempFile==0 || eMode!=PAGER_JOURNALMODE_WAL );
 
   /* Do allow the journalmode of an in-memory database to be set to
   ** anything other than MEMORY or OFF
@@ -39523,20 +41012,13 @@
   }
 
   if( eMode!=eOld ){
-    /* When changing between rollback modes, close the journal file prior
-    ** to the change.  But when changing from a rollback mode to WAL, keep
-    ** the journal open since there is a rollback-style transaction in play
-    ** used to convert the version numbers in the btree header.
-    */
-    if( isOpen(pPager->jfd) && eMode!=PAGER_JOURNALMODE_WAL ){
-      sqlite3OsClose(pPager->jfd);
-    }
 
     /* Change the journal mode. */
+    assert( pPager->eState!=PAGER_ERROR );
     pPager->journalMode = (u8)eMode;
 
     /* When transistioning from TRUNCATE or PERSIST to any other journal
-    ** mode except WAL (and we are not in locking_mode=EXCLUSIVE) then 
+    ** mode except WAL, unless the pager is in locking_mode=exclusive mode,
     ** delete the journal file.
     */
     assert( (PAGER_JOURNALMODE_TRUNCATE & 5)==1 );
@@ -39557,24 +41039,30 @@
       ** database file. This ensures that the journal file is not deleted
       ** while it is in use by some other client.
       */
-      int rc = SQLITE_OK;
-      int state = pPager->state;
-      if( state<PAGER_SHARED ){
-        rc = sqlite3PagerSharedLock(pPager);
-      }
-      if( pPager->state==PAGER_SHARED ){
-        assert( rc==SQLITE_OK );
-        rc = sqlite3OsLock(pPager->fd, RESERVED_LOCK);
-      }
-      if( rc==SQLITE_OK ){
+      sqlite3OsClose(pPager->jfd);
+      if( pPager->eLock>=RESERVED_LOCK ){
         sqlite3OsDelete(pPager->pVfs, pPager->zJournal, 0);
+      }else{
+        int rc = SQLITE_OK;
+        int state = pPager->eState;
+        assert( state==PAGER_OPEN || state==PAGER_READER );
+        if( state==PAGER_OPEN ){
+          rc = sqlite3PagerSharedLock(pPager);
+        }
+        if( pPager->eState==PAGER_READER ){
+          assert( rc==SQLITE_OK );
+          rc = pagerLockDb(pPager, RESERVED_LOCK);
+        }
+        if( rc==SQLITE_OK ){
+          sqlite3OsDelete(pPager->pVfs, pPager->zJournal, 0);
+        }
+        if( rc==SQLITE_OK && state==PAGER_READER ){
+          pagerUnlockDb(pPager, SHARED_LOCK);
+        }else if( state==PAGER_OPEN ){
+          pager_unlock(pPager);
+        }
+        assert( state==pPager->eState );
       }
-      if( rc==SQLITE_OK && state==PAGER_SHARED ){
-        sqlite3OsUnlock(pPager->fd, SHARED_LOCK);
-      }else if( state==PAGER_UNLOCK ){
-        pager_unlock(pPager);
-      }
-      assert( state==pPager->state );
     }
   }
 
@@ -39595,7 +41083,8 @@
 ** is unmodified.
 */
 SQLITE_PRIVATE int sqlite3PagerOkToChangeJournalMode(Pager *pPager){
-  if( pPager->dbModified ) return 0;
+  assert( assert_pager_state(pPager) );
+  if( pPager->eState>=PAGER_WRITER_CACHEMOD ) return 0;
   if( NEVER(isOpen(pPager->jfd) && pPager->journalOff>0) ) return 0;
   return 1;
 }
@@ -39649,7 +41138,7 @@
 */
 SQLITE_PRIVATE int sqlite3PagerWalSupported(Pager *pPager){
   const sqlite3_io_methods *pMethods = pPager->fd->pMethods;
-  return pMethods->iVersion>=2 && pMethods->xShmOpen!=0;
+  return pMethods->iVersion>=2 && pMethods->xShmMap!=0;
 }
 
 /*
@@ -39660,25 +41149,31 @@
 ** file (not a temp file or an in-memory database), and the WAL file
 ** is not already open, make an attempt to open it now. If successful,
 ** return SQLITE_OK. If an error occurs or the VFS used by the pager does 
-** not support the xShmXXX() methods, return an error code. *pisOpen is
+** not support the xShmXXX() methods, return an error code. *pbOpen is
 ** not modified in either case.
 **
 ** If the pager is open on a temp-file (or in-memory database), or if
-** the WAL file is already open, set *pisOpen to 1 and return SQLITE_OK
+** the WAL file is already open, set *pbOpen to 1 and return SQLITE_OK
 ** without doing anything.
 */
 SQLITE_PRIVATE int sqlite3PagerOpenWal(
   Pager *pPager,                  /* Pager object */
-  int *pisOpen                    /* OUT: Set to true if call is a no-op */
+  int *pbOpen                     /* OUT: Set to true if call is a no-op */
 ){
   int rc = SQLITE_OK;             /* Return code */
 
-  assert( pPager->state>=PAGER_SHARED );
-  assert( (pisOpen==0 && !pPager->tempFile && !pPager->pWal) || *pisOpen==0 );
+  assert( assert_pager_state(pPager) );
+  assert( pPager->eState==PAGER_OPEN   || pbOpen );
+  assert( pPager->eState==PAGER_READER || !pbOpen );
+  assert( pbOpen==0 || *pbOpen==0 );
+  assert( pbOpen!=0 || (!pPager->tempFile && !pPager->pWal) );
 
   if( !pPager->tempFile && !pPager->pWal ){
     if( !sqlite3PagerWalSupported(pPager) ) return SQLITE_CANTOPEN;
 
+    /* Close any rollback journal previously open */
+    sqlite3OsClose(pPager->jfd);
+
     /* Open the connection to the log file. If this operation fails, 
     ** (e.g. due to malloc() failure), unlock the database file and 
     ** return an error code.
@@ -39686,9 +41181,10 @@
     rc = sqlite3WalOpen(pPager->pVfs, pPager->fd, pPager->zWal, &pPager->pWal);
     if( rc==SQLITE_OK ){
       pPager->journalMode = PAGER_JOURNALMODE_WAL;
+      pPager->eState = PAGER_OPEN;
     }
   }else{
-    *pisOpen = 1;
+    *pbOpen = 1;
   }
 
   return rc;
@@ -39714,7 +41210,7 @@
   */
   if( !pPager->pWal ){
     int logexists = 0;
-    rc = sqlite3OsLock(pPager->fd, SQLITE_LOCK_SHARED);
+    rc = pagerLockDb(pPager, SHARED_LOCK);
     if( rc==SQLITE_OK ){
       rc = sqlite3OsAccess(
           pPager->pVfs, pPager->zWal, SQLITE_ACCESS_EXISTS, &logexists
@@ -39730,7 +41226,7 @@
   ** the database file, the log and log-summary files will be deleted.
   */
   if( rc==SQLITE_OK && pPager->pWal ){
-    rc = sqlite3OsLock(pPager->fd, SQLITE_LOCK_EXCLUSIVE);
+    rc = pagerLockDb(pPager, EXCLUSIVE_LOCK);
     if( rc==SQLITE_OK ){
       rc = sqlite3WalClose(pPager->pWal,
                            (pPager->noSync ? 0 : pPager->sync_flags), 
@@ -39740,7 +41236,7 @@
     }else{
       /* If we cannot get an EXCLUSIVE lock, downgrade the PENDING lock
       ** that we did get back to SHARED. */
-      sqlite3OsUnlock(pPager->fd, SQLITE_LOCK_SHARED);
+      pagerUnlockDb(pPager, SQLITE_LOCK_SHARED);
     }
   }
   return rc;
@@ -40060,6 +41556,10 @@
 **
 ** The actual header in the wal-index consists of two copies of this
 ** object.
+**
+** The szPage value can be any power of 2 between 512 and 32768, inclusive.
+** Or it can be 1 to represent a 65536-byte page.  The latter case was
+** added in 3.7.1 when support for 64K pages was added.  
 */
 struct WalIndexHdr {
   u32 iVersion;                   /* Wal-index version */
@@ -40067,7 +41567,7 @@
   u32 iChange;                    /* Counter incremented each transaction */
   u8 isInit;                      /* 1 when initialized */
   u8 bigEndCksum;                 /* True if checksums in WAL are big-endian */
-  u16 szPage;                     /* Database page size in bytes */
+  u16 szPage;                     /* Database page size in bytes. 1==64K */
   u32 mxFrame;                    /* Index of last valid frame in the WAL */
   u32 nPage;                      /* Size of database in pages */
   u32 aFrameCksum[2];             /* Checksum of last frame in log */
@@ -40178,12 +41678,12 @@
   u32 iCallback;             /* Value to pass to log callback (or 0) */
   int nWiData;               /* Size of array apWiData */
   volatile u32 **apWiData;   /* Pointer to wal-index content in memory */
-  u16 szPage;                /* Database page size */
+  u32 szPage;                /* Database page size */
   i16 readLock;              /* Which read lock is being held.  -1 for none */
   u8 exclusiveMode;          /* Non-zero if connection is in exclusive mode */
-  u8 isWIndexOpen;           /* True if ShmOpen() called on pDbFd */
   u8 writeLock;              /* True if in a write transaction */
   u8 ckptLock;               /* True if holding a checkpoint lock */
+  u8 readOnly;               /* True if the WAL file is open read-only */
   WalIndexHdr hdr;           /* Wal-index header for current transaction */
   const char *zWalName;      /* Name of WAL file */
   u32 nCkpt;                 /* Checkpoint sequence counter in the wal-header */
@@ -40263,14 +41763,15 @@
 
   /* Enlarge the pWal->apWiData[] array if required */
   if( pWal->nWiData<=iPage ){
-    int nByte = sizeof(u32 *)*(iPage+1);
+    int nByte = sizeof(u32*)*(iPage+1);
     volatile u32 **apNew;
     apNew = (volatile u32 **)sqlite3_realloc((void *)pWal->apWiData, nByte);
     if( !apNew ){
       *ppPage = 0;
       return SQLITE_NOMEM;
     }
-    memset((void *)&apNew[pWal->nWiData], 0, sizeof(u32 *)*(iPage+1-pWal->nWiData));
+    memset((void*)&apNew[pWal->nWiData], 0,
+           sizeof(u32*)*(iPage+1-pWal->nWiData));
     pWal->apWiData = apNew;
     pWal->nWiData = iPage+1;
   }
@@ -40446,9 +41947,10 @@
     return 0;
   }
 
-  /* A frame is only valid if a checksum of the first 16 bytes
-  ** of the frame-header, and the frame-data matches
-  ** the checksum in the last 8 bytes of the frame-header.
+  /* A frame is only valid if a checksum of the WAL header,
+  ** all prior frams, the first 16 bytes of this frame-header, 
+  ** and the frame-data matches the checksum in the last 8 
+  ** bytes of this frame-header.
   */
   nativeCksum = (pWal->hdr.bigEndCksum==SQLITE_BIGENDIAN);
   walChecksumBytes(nativeCksum, aFrame, 8, aCksum, aCksum);
@@ -40708,7 +42210,7 @@
   if( rc==SQLITE_OK ){
     int iKey;                     /* Hash table key */
     int idx;                      /* Value to write to hash-table slot */
-    TESTONLY( int nCollide = 0;   /* Number of hash collisions */ )
+    int nCollide;                 /* Number of hash collisions */
 
     idx = iFrame - iZero;
     assert( idx <= HASHTABLE_NSLOT/2 + 1 );
@@ -40733,8 +42235,9 @@
     }
 
     /* Write the aPgno[] array entry and the hash-table slot. */
+    nCollide = idx;
     for(iKey=walHash(iPage); aHash[iKey]; iKey=walNextHash(iKey)){
-      assert( nCollide++ < idx );
+      if( (nCollide--)==0 ) return SQLITE_CORRUPT_BKPT;
     }
     aPgno[idx] = iPage;
     aHash[iKey] = (ht_slot)idx;
@@ -40846,7 +42349,7 @@
       goto finished;
     }
     pWal->hdr.bigEndCksum = (u8)(magic&0x00000001);
-    pWal->szPage = (u16)szPage;
+    pWal->szPage = szPage;
     pWal->nCkpt = sqlite3Get4byte(&aBuf[12]);
     memcpy(&pWal->hdr.aSalt, &aBuf[16], 8);
 
@@ -40896,7 +42399,9 @@
       if( nTruncate ){
         pWal->hdr.mxFrame = iFrame;
         pWal->hdr.nPage = nTruncate;
-        pWal->hdr.szPage = (u16)szPage;
+        pWal->hdr.szPage = (u16)((szPage&0xff00) | (szPage>>16));
+        testcase( szPage<=32768 );
+        testcase( szPage>=65536 );
         aFrameCksum[0] = pWal->hdr.aFrameCksum[0];
         aFrameCksum[1] = pWal->hdr.aFrameCksum[1];
       }
@@ -40921,6 +42426,17 @@
     pInfo->nBackfill = 0;
     pInfo->aReadMark[0] = 0;
     for(i=1; i<WAL_NREADER; i++) pInfo->aReadMark[i] = READMARK_NOT_USED;
+
+    /* If more than one frame was recovered from the log file, report an
+    ** event via sqlite3_log(). This is to help with identifying performance
+    ** problems caused by applications routinely shutting down without
+    ** checkpointing the log file.
+    */
+    if( pWal->hdr.nPage ){
+      sqlite3_log(SQLITE_OK, "Recovered %d frames from WAL file %s",
+          pWal->hdr.nPage, pWal->zWalName
+      );
+    }
   }
 
 recovery_error:
@@ -40933,10 +42449,7 @@
 ** Close an open wal-index.
 */
 static void walIndexClose(Wal *pWal, int isDelete){
-  if( pWal->isWIndexOpen ){
-    sqlite3OsShmClose(pWal->pDbFd, isDelete);
-    pWal->isWIndexOpen = 0;
-  }
+  sqlite3OsShmUnmap(pWal->pDbFd, isDelete);
 }
 
 /* 
@@ -40990,15 +42503,13 @@
   pRet->pWalFd = (sqlite3_file *)&pRet[1];
   pRet->pDbFd = pDbFd;
   pRet->readLock = -1;
-  sqlite3_randomness(8, &pRet->hdr.aSalt);
   pRet->zWalName = zWalName;
-  rc = sqlite3OsShmOpen(pDbFd);
 
   /* Open file handle on the write-ahead log file. */
-  if( rc==SQLITE_OK ){
-    pRet->isWIndexOpen = 1;
-    flags = (SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE|SQLITE_OPEN_MAIN_JOURNAL);
-    rc = sqlite3OsOpen(pVfs, zWalName, pRet->pWalFd, flags, &flags);
+  flags = (SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE|SQLITE_OPEN_WAL);
+  rc = sqlite3OsOpen(pVfs, zWalName, pRet->pWalFd, flags, &flags);
+  if( rc==SQLITE_OK && flags&SQLITE_OPEN_READONLY ){
+    pRet->readOnly = 1;
   }
 
   if( rc!=SQLITE_OK ){
@@ -41221,7 +42732,11 @@
       ht_slot *aIndex;            /* Sorted index for this segment */
 
       aPgno++;
-      nEntry = (int)(((i+1)==nSegment)?(int)(iLast-iZero):(u32 *)aHash-(u32 *)aPgno);
+      if( (i+1)==nSegment ){
+        nEntry = (int)(iLast - iZero);
+      }else{
+        nEntry = (int)((u32*)aHash - (u32*)aPgno);
+      }
       aIndex = &((ht_slot *)&p->aSegment[p->nSegment])[iZero];
       iZero++;
   
@@ -41282,14 +42797,18 @@
   u8 *zBuf                        /* Temporary buffer to use */
 ){
   int rc;                         /* Return code */
-  int szPage = pWal->hdr.szPage;  /* Database page-size */
+  int szPage;                     /* Database page-size */
   WalIterator *pIter = 0;         /* Wal iterator context */
   u32 iDbpage = 0;                /* Next database page to write */
   u32 iFrame = 0;                 /* Wal frame containing data for iDbpage */
   u32 mxSafeFrame;                /* Max frame that can be backfilled */
+  u32 mxPage;                     /* Max database page to write */
   int i;                          /* Loop counter */
   volatile WalCkptInfo *pInfo;    /* The checkpoint status information */
 
+  szPage = (pWal->hdr.szPage&0xfe00) + ((pWal->hdr.szPage&0x0001)<<16);
+  testcase( szPage<=32768 );
+  testcase( szPage>=65536 );
   if( pWal->hdr.mxFrame==0 ) return SQLITE_OK;
 
   /* Allocate the iterator */
@@ -41300,7 +42819,7 @@
   assert( pIter );
 
   /*** TODO:  Move this test out to the caller.  Make it an assert() here ***/
-  if( pWal->hdr.szPage!=nBuf ){
+  if( szPage!=nBuf ){
     rc = SQLITE_CORRUPT_BKPT;
     goto walcheckpoint_out;
   }
@@ -41311,6 +42830,7 @@
   ** cannot be backfilled from the WAL.
   */
   mxSafeFrame = pWal->hdr.mxFrame;
+  mxPage = pWal->hdr.nPage;
   pInfo = walCkptInfo(pWal);
   for(i=1; i<WAL_NREADER; i++){
     u32 y = pInfo->aReadMark[i];
@@ -41331,6 +42851,7 @@
   if( pInfo->nBackfill<mxSafeFrame
    && (rc = walLockExclusive(pWal, WAL_READ_LOCK(0), 1))==SQLITE_OK
   ){
+    i64 nSize;                    /* Current size of database file */
     u32 nBackfill = pInfo->nBackfill;
 
     /* Sync the WAL to disk */
@@ -41338,11 +42859,22 @@
       rc = sqlite3OsSync(pWal->pWalFd, sync_flags);
     }
 
+    /* If the database file may grow as a result of this checkpoint, hint
+    ** about the eventual size of the db file to the VFS layer. 
+    */
+    if( rc==SQLITE_OK ){
+      i64 nReq = ((i64)mxPage * szPage);
+      rc = sqlite3OsFileSize(pWal->pDbFd, &nSize);
+      if( rc==SQLITE_OK && nSize<nReq ){
+        sqlite3OsFileControl(pWal->pDbFd, SQLITE_FCNTL_SIZE_HINT, &nReq);
+      }
+    }
+
     /* Iterate through the contents of the WAL, copying data to the db file. */
     while( rc==SQLITE_OK && 0==walIteratorNext(pIter, &iDbpage, &iFrame) ){
       i64 iOffset;
       assert( walFramePgno(pWal, iFrame)==iDbpage );
-      if( iFrame<=nBackfill || iFrame>mxSafeFrame ) continue;
+      if( iFrame<=nBackfill || iFrame>mxSafeFrame || iDbpage>mxPage ) continue;
       iOffset = walFrameOffset(iFrame, szPage) + WAL_FRAME_HDRSIZE;
       /* testcase( IS_BIG_INT(iOffset) ); // requires a 4GiB WAL file */
       rc = sqlite3OsRead(pWal->pWalFd, zBuf, szPage, iOffset);
@@ -41449,7 +42981,7 @@
   /* The first page of the wal-index must be mapped at this point. */
   assert( pWal->nWiData>0 && pWal->apWiData[0] );
 
-  /* Read the header. This might happen currently with a write to the
+  /* Read the header. This might happen concurrently with a write to the
   ** same area of shared memory on a different CPU in a SMP,
   ** meaning it is possible that an inconsistent snapshot is read
   ** from the file. If this happens, return non-zero.
@@ -41478,7 +43010,9 @@
   if( memcmp(&pWal->hdr, &h1, sizeof(WalIndexHdr)) ){
     *pChanged = 1;
     memcpy(&pWal->hdr, &h1, sizeof(WalIndexHdr));
-    pWal->szPage = pWal->hdr.szPage;
+    pWal->szPage = (pWal->hdr.szPage&0xfe00) + ((pWal->hdr.szPage&0x0001)<<16);
+    testcase( pWal->szPage<=32768 );
+    testcase( pWal->szPage>=65536 );
   }
 
   /* The header was successfully read. Return zero. */
@@ -41633,8 +43167,16 @@
       ** WAL_RETRY this routine will be called again and will probably be
       ** right on the second iteration.
       */
-      rc = walLockShared(pWal, WAL_RECOVER_LOCK);
-      if( rc==SQLITE_OK ){
+      if( pWal->apWiData[0]==0 ){
+        /* This branch is taken when the xShmMap() method returns SQLITE_BUSY.
+        ** We assume this is a transient condition, so return WAL_RETRY. The
+        ** xShmMap() implementation used by the default unix and win32 VFS 
+        ** modules may return SQLITE_BUSY due to a race condition in the 
+        ** code that determines whether or not the shared-memory region 
+        ** must be zeroed before the requested page is returned.
+        */
+        rc = WAL_RETRY;
+      }else if( SQLITE_OK==(rc = walLockShared(pWal, WAL_RECOVER_LOCK)) ){
         walUnlockShared(pWal, WAL_RECOVER_LOCK);
         rc = WAL_RETRY;
       }else if( rc==SQLITE_BUSY ){
@@ -41789,6 +43331,7 @@
 ** read-lock.
 */
 SQLITE_PRIVATE void sqlite3WalEndReadTransaction(Wal *pWal){
+  sqlite3WalEndWriteTransaction(pWal);
   if( pWal->readLock>=0 ){
     walUnlockShared(pWal, WAL_READ_LOCK(pWal->readLock));
     pWal->readLock = -1;
@@ -41858,18 +43401,23 @@
     volatile u32 *aPgno;          /* Pointer to array of page numbers */
     u32 iZero;                    /* Frame number corresponding to aPgno[0] */
     int iKey;                     /* Hash slot index */
-    int rc;
+    int nCollide;                 /* Number of hash collisions remaining */
+    int rc;                       /* Error code */
 
     rc = walHashGet(pWal, iHash, &aHash, &aPgno, &iZero);
     if( rc!=SQLITE_OK ){
       return rc;
     }
+    nCollide = HASHTABLE_NSLOT;
     for(iKey=walHash(pgno); aHash[iKey]; iKey=walNextHash(iKey)){
       u32 iFrame = aHash[iKey] + iZero;
       if( iFrame<=iLast && aPgno[aHash[iKey]]==pgno ){
         assert( iFrame>iRead );
         iRead = iFrame;
       }
+      if( (nCollide--)==0 ){
+        return SQLITE_CORRUPT_BKPT;
+      }
     }
   }
 
@@ -41894,7 +43442,13 @@
   ** required page. Read and return data from the log file.
   */
   if( iRead ){
-    i64 iOffset = walFrameOffset(iRead, pWal->hdr.szPage) + WAL_FRAME_HDRSIZE;
+    int sz;
+    i64 iOffset;
+    sz = pWal->hdr.szPage;
+    sz = (pWal->hdr.szPage&0xfe00) + ((pWal->hdr.szPage&0x0001)<<16);
+    testcase( sz<=32768 );
+    testcase( sz>=65536 );
+    iOffset = walFrameOffset(iRead, sz) + WAL_FRAME_HDRSIZE;
     *pInWal = 1;
     /* testcase( IS_BIG_INT(iOffset) ); // requires a 4GiB WAL */
     return sqlite3OsRead(pWal->pWalFd, pOut, nOut, iOffset);
@@ -41906,11 +43460,13 @@
 
 
 /* 
-** Set *pPgno to the size of the database file (or zero, if unknown).
+** Return the size of the database in pages (or zero, if unknown).
 */
-SQLITE_PRIVATE void sqlite3WalDbsize(Wal *pWal, Pgno *pPgno){
-  assert( pWal->readLock>=0 || pWal->lockError );
-  *pPgno = pWal->hdr.nPage;
+SQLITE_PRIVATE Pgno sqlite3WalDbsize(Wal *pWal){
+  if( pWal && ALWAYS(pWal->readLock>=0) ){
+    return pWal->hdr.nPage;
+  }
+  return 0;
 }
 
 
@@ -41934,6 +43490,10 @@
   ** transaction. */
   assert( pWal->readLock>=0 );
 
+  if( pWal->readOnly ){
+    return SQLITE_READONLY;
+  }
+
   /* Only one writer allowed at a time.  Get the write lock.  Return
   ** SQLITE_BUSY if unable.
   */
@@ -41961,8 +43521,10 @@
 ** routine merely releases the lock.
 */
 SQLITE_PRIVATE int sqlite3WalEndWriteTransaction(Wal *pWal){
-  walUnlockExclusive(pWal, WAL_WRITE_LOCK, 1);
-  pWal->writeLock = 0;
+  if( pWal->writeLock ){
+    walUnlockExclusive(pWal, WAL_WRITE_LOCK, 1);
+    pWal->writeLock = 0;
+  }
   return SQLITE_OK;
 }
 
@@ -41980,7 +43542,7 @@
 */
 SQLITE_PRIVATE int sqlite3WalUndo(Wal *pWal, int (*xUndo)(void *, Pgno), void *pUndoCtx){
   int rc = SQLITE_OK;
-  if( pWal->writeLock ){
+  if( ALWAYS(pWal->writeLock) ){
     Pgno iMax = pWal->hdr.mxFrame;
     Pgno iFrame;
   
@@ -42163,12 +43725,13 @@
     sqlite3Put4byte(&aWalHdr[4], WAL_MAX_VERSION);
     sqlite3Put4byte(&aWalHdr[8], szPage);
     sqlite3Put4byte(&aWalHdr[12], pWal->nCkpt);
+    sqlite3_randomness(8, pWal->hdr.aSalt);
     memcpy(&aWalHdr[16], pWal->hdr.aSalt, 8);
     walChecksumBytes(1, aWalHdr, WAL_HDRSIZE-2*4, 0, aCksum);
     sqlite3Put4byte(&aWalHdr[24], aCksum[0]);
     sqlite3Put4byte(&aWalHdr[28], aCksum[1]);
     
-    pWal->szPage = (u16)szPage;
+    pWal->szPage = szPage;
     pWal->hdr.bigEndCksum = SQLITE_BIGENDIAN;
     pWal->hdr.aFrameCksum[0] = aCksum[0];
     pWal->hdr.aFrameCksum[1] = aCksum[1];
@@ -42179,7 +43742,7 @@
       return rc;
     }
   }
-  assert( pWal->szPage==szPage );
+  assert( (int)pWal->szPage==szPage );
 
   /* Write the log file. */
   for(p=pList; p; p=p->pDirty){
@@ -42263,7 +43826,9 @@
 
   if( rc==SQLITE_OK ){
     /* Update the private copy of the header. */
-    pWal->hdr.szPage = (u16)szPage;
+    pWal->hdr.szPage = (u16)((szPage&0xff00) | (szPage>>16));
+    testcase( szPage<=32768 );
+    testcase( szPage>=65536 );
     pWal->hdr.mxFrame = iFrame;
     if( isCommit ){
       pWal->hdr.iChange++;
@@ -42475,7 +44040,7 @@
 **
 ** The file is divided into pages.  The first page is called page 1,
 ** the second is page 2, and so forth.  A page number of zero indicates
-** "no such page".  The page size can be any power of 2 between 512 and 32768.
+** "no such page".  The page size can be any power of 2 between 512 and 65536.
 ** Each page can be either a btree page, a freelist page, an overflow
 ** page, or a pointer-map page.
 **
@@ -42837,18 +44402,19 @@
   u8 pageSizeFixed;     /* True if the page size can no longer be changed */
   u8 secureDelete;      /* True if secure_delete is enabled */
   u8 initiallyEmpty;    /* Database is empty at start of transaction */
+  u8 openFlags;         /* Flags to sqlite3BtreeOpen() */
 #ifndef SQLITE_OMIT_AUTOVACUUM
   u8 autoVacuum;        /* True if auto-vacuum is enabled */
   u8 incrVacuum;        /* True if incr-vacuum is enabled */
 #endif
-  u16 pageSize;         /* Total number of bytes on a page */
-  u16 usableSize;       /* Number of usable bytes on each page */
   u16 maxLocal;         /* Maximum local payload in non-LEAFDATA tables */
   u16 minLocal;         /* Minimum local payload in non-LEAFDATA tables */
   u16 maxLeaf;          /* Maximum local payload in a LEAFDATA table */
   u16 minLeaf;          /* Minimum local payload in a LEAFDATA table */
   u8 inTransaction;     /* Transaction state */
   u8 doNotUseWAL;       /* If true, do not open write-ahead-log file */
+  u32 pageSize;         /* Total number of bytes on a page */
+  u32 usableSize;       /* Number of usable bytes on each page */
   int nTransaction;     /* Number of open transactions (read + write) */
   u32 nPage;            /* Number of pages in the database */
   void *pSchema;        /* Pointer to space allocated by sqlite3BtreeSchema() */
@@ -43447,7 +45013,16 @@
 # define TRACE(X)
 #endif
 
-
+/*
+** Extract a 2-byte big-endian integer from an array of unsigned bytes.
+** But if the value is zero, make it 65536.
+**
+** This routine is used to extract the "offset to cell content area" value
+** from the header of a btree page.  If the page size is 65536 and the page
+** is empty, the offset should be 65536, but the 2-byte value stores zero.
+** This routine makes the necessary adjustment to 65536.
+*/
+#define get2byteNotZero(X)  (((((int)get2byte(X))-1)&0xffff)+1)
 
 #ifndef SQLITE_OMIT_SHARED_CACHE
 /*
@@ -44136,11 +45711,16 @@
 ** Given a page number of a regular database page, return the page
 ** number for the pointer-map page that contains the entry for the
 ** input page number.
+**
+** Return 0 (not a valid page) for pgno==1 since there is
+** no pointer map associated with page 1.  The integrity_check logic
+** requires that ptrmapPageno(*,1)!=1.
 */
 static Pgno ptrmapPageno(BtShared *pBt, Pgno pgno){
   int nPagesPerMapPage;
   Pgno iPtrMap, ret;
   assert( sqlite3_mutex_held(pBt->mutex) );
+  if( pgno<2 ) return 0;
   nPagesPerMapPage = (pBt->usableSize/5)+1;
   iPtrMap = (pgno-2)/nPagesPerMapPage;
   ret = (iPtrMap*nPagesPerMapPage) + 2; 
@@ -44569,7 +46149,7 @@
   nFrag = data[hdr+7];
   assert( pPage->cellOffset == hdr + 12 - 4*pPage->leaf );
   gap = pPage->cellOffset + 2*pPage->nCell;
-  top = get2byte(&data[hdr+5]);
+  top = get2byteNotZero(&data[hdr+5]);
   if( gap>top ) return SQLITE_CORRUPT_BKPT;
   testcase( gap+2==top );
   testcase( gap+1==top );
@@ -44579,7 +46159,7 @@
     /* Always defragment highly fragmented pages */
     rc = defragmentPage(pPage);
     if( rc ) return rc;
-    top = get2byte(&data[hdr+5]);
+    top = get2byteNotZero(&data[hdr+5]);
   }else if( gap+2<=top ){
     /* Search the freelist looking for a free slot big enough to satisfy 
     ** the request. The allocation is made from the first free slot in 
@@ -44621,7 +46201,7 @@
   if( gap+2+nByte>top ){
     rc = defragmentPage(pPage);
     if( rc ) return rc;
-    top = get2byte(&data[hdr+5]);
+    top = get2byteNotZero(&data[hdr+5]);
     assert( gap+nByte<=top );
   }
 
@@ -44787,10 +46367,10 @@
     u8 hdr;            /* Offset to beginning of page header */
     u8 *data;          /* Equal to pPage->aData */
     BtShared *pBt;        /* The main btree structure */
-    u16 usableSize;    /* Amount of usable space on each page */
+    int usableSize;    /* Amount of usable space on each page */
     u16 cellOffset;    /* Offset from start of page to first cell pointer */
-    u16 nFree;         /* Number of unused bytes on the page */
-    u16 top;           /* First byte of the cell content area */
+    int nFree;         /* Number of unused bytes on the page */
+    int top;           /* First byte of the cell content area */
     int iCellFirst;    /* First allowable cell or freeblock offset */
     int iCellLast;     /* Last possible cell or freeblock offset */
 
@@ -44799,12 +46379,12 @@
     hdr = pPage->hdrOffset;
     data = pPage->aData;
     if( decodeFlags(pPage, data[hdr]) ) return SQLITE_CORRUPT_BKPT;
-    assert( pBt->pageSize>=512 && pBt->pageSize<=32768 );
-    pPage->maskPage = pBt->pageSize - 1;
+    assert( pBt->pageSize>=512 && pBt->pageSize<=65536 );
+    pPage->maskPage = (u16)(pBt->pageSize - 1);
     pPage->nOverflow = 0;
     usableSize = pBt->usableSize;
     pPage->cellOffset = cellOffset = hdr + 12 - 4*pPage->leaf;
-    top = get2byte(&data[hdr+5]);
+    top = get2byteNotZero(&data[hdr+5]);
     pPage->nCell = get2byte(&data[hdr+3]);
     if( pPage->nCell>MX_CELL(pBt) ){
       /* To many cells for a single page.  The page must be corrupt */
@@ -44903,13 +46483,13 @@
   memset(&data[hdr+1], 0, 4);
   data[hdr+7] = 0;
   put2byte(&data[hdr+5], pBt->usableSize);
-  pPage->nFree = pBt->usableSize - first;
+  pPage->nFree = (u16)(pBt->usableSize - first);
   decodeFlags(pPage, flags);
   pPage->hdrOffset = hdr;
   pPage->cellOffset = first;
   pPage->nOverflow = 0;
-  assert( pBt->pageSize>=512 && pBt->pageSize<=32768 );
-  pPage->maskPage = pBt->pageSize - 1;
+  assert( pBt->pageSize>=512 && pBt->pageSize<=65536 );
+  pPage->maskPage = (u16)(pBt->pageSize - 1);
   pPage->nCell = 0;
   pPage->isInit = 1;
 }
@@ -45073,11 +46653,20 @@
 ** Open a database file.
 ** 
 ** zFilename is the name of the database file.  If zFilename is NULL
-** a new database with a random name is created.  This randomly named
-** database file will be deleted when sqlite3BtreeClose() is called.
+** then an ephemeral database is created.  The ephemeral database might
+** be exclusively in memory, or it might use a disk-based memory cache.
+** Either way, the ephemeral database will be automatically deleted 
+** when sqlite3BtreeClose() is called.
+**
 ** If zFilename is ":memory:" then an in-memory database is created
 ** that is automatically destroyed when it is closed.
 **
+** The "flags" parameter is a bitmask that might contain bits
+** BTREE_OMIT_JOURNAL and/or BTREE_NO_READLOCK.  The BTREE_NO_READLOCK
+** bit is also set if the SQLITE_NoReadlock flags is set in db->flags.
+** These flags are passed through into sqlite3PagerOpen() and must
+** be the same values as PAGER_OMIT_JOURNAL and PAGER_NO_READLOCK.
+**
 ** If the database is already opened in the same database connection
 ** and we are in shared cache mode, then the open will fail with an
 ** SQLITE_CONSTRAINT error.  We cannot allow two or more BtShared
@@ -45099,6 +46688,9 @@
   u8 nReserve;                   /* Byte of unused space on each page */
   unsigned char zDbHeader[100];  /* Database header content */
 
+  /* True if opening an ephemeral, temporary database */
+  const int isTempDb = zFilename==0 || zFilename[0]==0;
+
   /* Set the variable isMemdb to true for an in-memory database, or 
   ** false for a file-based database. This symbol is only required if
   ** either of the shared-data or autovacuum features are compiled 
@@ -45108,13 +46700,30 @@
   #ifdef SQLITE_OMIT_MEMORYDB
     const int isMemdb = 0;
   #else
-    const int isMemdb = zFilename && !strcmp(zFilename, ":memory:");
+    const int isMemdb = (zFilename && strcmp(zFilename, ":memory:")==0)
+                         || (isTempDb && sqlite3TempInMemory(db));
   #endif
 #endif
 
   assert( db!=0 );
   assert( sqlite3_mutex_held(db->mutex) );
+  assert( (flags&0xff)==flags );   /* flags fit in 8 bits */
 
+  /* Only a BTREE_SINGLE database can be BTREE_UNORDERED */
+  assert( (flags & BTREE_UNORDERED)==0 || (flags & BTREE_SINGLE)!=0 );
+
+  /* A BTREE_SINGLE database is always a temporary and/or ephemeral */
+  assert( (flags & BTREE_SINGLE)==0 || isTempDb );
+
+  if( db->flags & SQLITE_NoReadlock ){
+    flags |= BTREE_NO_READLOCK;
+  }
+  if( isMemdb ){
+    flags |= BTREE_MEMORY;
+  }
+  if( (vfsFlags & SQLITE_OPEN_MAIN_DB)!=0 && (isMemdb || isTempDb) ){
+    vfsFlags = (vfsFlags & ~SQLITE_OPEN_MAIN_DB) | SQLITE_OPEN_TEMP_DB;
+  }
   pVfs = db->pVfs;
   p = sqlite3MallocZero(sizeof(Btree));
   if( !p ){
@@ -45132,7 +46741,7 @@
   ** If this Btree is a candidate for shared cache, try to find an
   ** existing BtShared object that we can share with
   */
-  if( isMemdb==0 && zFilename && zFilename[0] ){
+  if( isMemdb==0 && isTempDb==0 ){
     if( vfsFlags & SQLITE_OPEN_SHAREDCACHE ){
       int nFullPathname = pVfs->mxPathname+1;
       char *zFullPathname = sqlite3Malloc(nFullPathname);
@@ -45207,6 +46816,7 @@
     if( rc!=SQLITE_OK ){
       goto btree_open_out;
     }
+    pBt->openFlags = (u8)flags;
     pBt->db = db;
     sqlite3PagerSetBusyhandler(pBt->pPager, btreeInvokeBusyHandler, pBt);
     p->pBt = pBt;
@@ -45217,7 +46827,7 @@
 #ifdef SQLITE_SECURE_DELETE
     pBt->secureDelete = 1;
 #endif
-    pBt->pageSize = get2byte(&zDbHeader[16]);
+    pBt->pageSize = (zDbHeader[16]<<8) | (zDbHeader[17]<<16);
     if( pBt->pageSize<512 || pBt->pageSize>SQLITE_MAX_PAGE_SIZE
          || ((pBt->pageSize-1)&pBt->pageSize)!=0 ){
       pBt->pageSize = 0;
@@ -45311,6 +46921,14 @@
     sqlite3_free(pBt);
     sqlite3_free(p);
     *ppBtree = 0;
+  }else{
+    /* If the B-Tree was successfully opened, set the pager-cache size to the
+    ** default value. Except, when opening on an existing shared pager-cache,
+    ** do not change the pager-cache size.
+    */
+    if( sqlite3BtreeSchema(p, 0, 0)==0 ){
+      sqlite3PagerSetCachesize(p->pBt->pPager, SQLITE_DEFAULT_CACHE_SIZE);
+    }
   }
   if( mutexOpen ){
     assert( sqlite3_mutex_held(mutexOpen) );
@@ -45419,7 +47037,7 @@
     if( pBt->xFreeSchema && pBt->pSchema ){
       pBt->xFreeSchema(pBt->pSchema);
     }
-    sqlite3_free(pBt->pSchema);
+    sqlite3DbFree(0, pBt->pSchema);
     freeTempSpace(pBt);
     sqlite3_free(pBt);
   }
@@ -45531,7 +47149,7 @@
         ((pageSize-1)&pageSize)==0 ){
     assert( (pageSize & 7)==0 );
     assert( !pBt->pPage1 && !pBt->pCursor );
-    pBt->pageSize = (u16)pageSize;
+    pBt->pageSize = (u32)pageSize;
     freeTempSpace(pBt);
   }
   rc = sqlite3PagerSetPagesize(pBt->pPager, &pBt->pageSize, nReserve);
@@ -45666,15 +47284,13 @@
   ** a valid database file. 
   */
   nPage = nPageHeader = get4byte(28+(u8*)pPage1->aData);
-  if( (rc = sqlite3PagerPagecount(pBt->pPager, &nPageFile))!=SQLITE_OK ){;
-    goto page1_init_failed;
-  }
+  sqlite3PagerPagecount(pBt->pPager, &nPageFile);
   if( nPage==0 || memcmp(24+(u8*)pPage1->aData, 92+(u8*)pPage1->aData,4)!=0 ){
     nPage = nPageFile;
   }
   if( nPage>0 ){
-    int pageSize;
-    int usableSize;
+    u32 pageSize;
+    u32 usableSize;
     u8 *page1 = pPage1->aData;
     rc = SQLITE_NOTADB;
     if( memcmp(page1, zMagicHeader, 16)!=0 ){
@@ -45725,15 +47341,16 @@
     if( memcmp(&page1[21], "\100\040\040",3)!=0 ){
       goto page1_init_failed;
     }
-    pageSize = get2byte(&page1[16]);
-    if( ((pageSize-1)&pageSize)!=0 || pageSize<512 ||
-        (SQLITE_MAX_PAGE_SIZE<32768 && pageSize>SQLITE_MAX_PAGE_SIZE)
+    pageSize = (page1[16]<<8) | (page1[17]<<16);
+    if( ((pageSize-1)&pageSize)!=0
+     || pageSize>SQLITE_MAX_PAGE_SIZE 
+     || pageSize<=256 
     ){
       goto page1_init_failed;
     }
     assert( (pageSize & 7)==0 );
     usableSize = pageSize - page1[20];
-    if( pageSize!=pBt->pageSize ){
+    if( (u32)pageSize!=pBt->pageSize ){
       /* After reading the first page of the database assuming a page size
       ** of BtShared.pageSize, we have discovered that the page-size is
       ** actually pageSize. Unlock the database, leave pBt->pPage1 at
@@ -45741,8 +47358,8 @@
       ** again with the correct page-size.
       */
       releasePage(pPage1);
-      pBt->usableSize = (u16)usableSize;
-      pBt->pageSize = (u16)pageSize;
+      pBt->usableSize = usableSize;
+      pBt->pageSize = pageSize;
       freeTempSpace(pBt);
       rc = sqlite3PagerSetPagesize(pBt->pPager, &pBt->pageSize,
                                    pageSize-usableSize);
@@ -45755,8 +47372,8 @@
     if( usableSize<480 ){
       goto page1_init_failed;
     }
-    pBt->pageSize = (u16)pageSize;
-    pBt->usableSize = (u16)usableSize;
+    pBt->pageSize = pageSize;
+    pBt->usableSize = usableSize;
 #ifndef SQLITE_OMIT_AUTOVACUUM
     pBt->autoVacuum = (get4byte(&page1[36 + 4*4])?1:0);
     pBt->incrVacuum = (get4byte(&page1[36 + 7*4])?1:0);
@@ -45772,14 +47389,14 @@
   **     9-byte nKey value
   **     4-byte nData value
   **     4-byte overflow page pointer
-  ** So a cell consists of a 2-byte poiner, a header which is as much as
+  ** So a cell consists of a 2-byte pointer, a header which is as much as
   ** 17 bytes long, 0 to N bytes of payload, and an optional 4 byte overflow
   ** page pointer.
   */
-  pBt->maxLocal = (pBt->usableSize-12)*64/255 - 23;
-  pBt->minLocal = (pBt->usableSize-12)*32/255 - 23;
-  pBt->maxLeaf = pBt->usableSize - 35;
-  pBt->minLeaf = (pBt->usableSize-12)*32/255 - 23;
+  pBt->maxLocal = (u16)((pBt->usableSize-12)*64/255 - 23);
+  pBt->minLocal = (u16)((pBt->usableSize-12)*32/255 - 23);
+  pBt->maxLeaf = (u16)(pBt->usableSize - 35);
+  pBt->minLeaf = (u16)((pBt->usableSize-12)*32/255 - 23);
   assert( pBt->maxLeaf + 23 <= MX_CELL_SIZE(pBt) );
   pBt->pPage1 = pPage1;
   pBt->nPage = nPage;
@@ -45832,7 +47449,8 @@
   if( rc ) return rc;
   memcpy(data, zMagicHeader, sizeof(zMagicHeader));
   assert( sizeof(zMagicHeader)==16 );
-  put2byte(&data[16], pBt->pageSize);
+  data[16] = (u8)((pBt->pageSize>>8)&0xff);
+  data[17] = (u8)((pBt->pageSize>>16)&0xff);
   data[18] = 1;
   data[19] = 1;
   assert( pBt->usableSize<=pBt->pageSize && pBt->usableSize+255>=pBt->pageSize);
@@ -45984,13 +47602,27 @@
     if( p->inTrans>pBt->inTransaction ){
       pBt->inTransaction = p->inTrans;
     }
-#ifndef SQLITE_OMIT_SHARED_CACHE
     if( wrflag ){
+      MemPage *pPage1 = pBt->pPage1;
+#ifndef SQLITE_OMIT_SHARED_CACHE
       assert( !pBt->pWriter );
       pBt->pWriter = p;
       pBt->isExclusive = (u8)(wrflag>1);
-    }
 #endif
+
+      /* If the db-size header field is incorrect (as it may be if an old
+      ** client has been writing the database file), update it now. Doing
+      ** this sooner rather than later means the database size can safely 
+      ** re-read the database size from page 1 if a savepoint or transaction
+      ** rollback occurs within the transaction.
+      */
+      if( pBt->nPage!=get4byte(&pPage1->aData[28]) ){
+        rc = sqlite3PagerWrite(pPage1->pDbPage);
+        if( rc==SQLITE_OK ){
+          put4byte(&pPage1->aData[28], pBt->nPage);
+        }
+      }
+    }
   }
 
 
@@ -46729,9 +48361,11 @@
       if( iSavepoint<0 && pBt->initiallyEmpty ) pBt->nPage = 0;
       rc = newDatabase(pBt);
       pBt->nPage = get4byte(28 + pBt->pPage1->aData);
-      if( pBt->nPage==0 ){
-        sqlite3PagerPagecount(pBt->pPager, (int*)&pBt->nPage);
-      }
+
+      /* The database size was written into the offset 28 of the header
+      ** when the transaction started, so we know that the value at offset
+      ** 28 is nonzero. */
+      assert( pBt->nPage>0 );
     }
     sqlite3BtreeLeave(p);
   }
@@ -47827,9 +49461,9 @@
         pCur->validNKey = 1;
         pCur->info.nKey = nCellKey;
       }else{
-        /* The maximum supported page-size is 32768 bytes. This means that
+        /* The maximum supported page-size is 65536 bytes. This means that
         ** the maximum number of record bytes stored on an index B-Tree
-        ** page is at most 8198 bytes, which may be stored as a 2-byte
+        ** page is less than 16384 bytes and may be stored as a 2-byte
         ** varint. This information is used to attempt to avoid parsing 
         ** the entire cell by checking for the cases where the record is 
         ** stored entirely within the b-tree page by inspecting the first 
@@ -48192,6 +49826,10 @@
           if( !pPrevTrunk ){
             memcpy(&pPage1->aData[32], &pTrunk->aData[0], 4);
           }else{
+            rc = sqlite3PagerWrite(pPrevTrunk->pDbPage);
+            if( rc!=SQLITE_OK ){
+              goto end_allocate_page;
+            }
             memcpy(&pPrevTrunk->aData[0], &pTrunk->aData[0], 4);
           }
         }else{
@@ -48498,7 +50136,7 @@
   Pgno ovflPgno;
   int rc;
   int nOvfl;
-  u16 ovflPageSize;
+  u32 ovflPageSize;
 
   assert( sqlite3_mutex_held(pPage->pBt->mutex) );
   btreeParseCellPtr(pPage, pCell, &info);
@@ -48723,7 +50361,7 @@
 */
 static void dropCell(MemPage *pPage, int idx, int sz, int *pRC){
   int i;          /* Loop counter */
-  int pc;         /* Offset to cell content of cell being deleted */
+  u32 pc;         /* Offset to cell content of cell being deleted */
   u8 *data;       /* pPage->aData */
   u8 *ptr;        /* Used to move bytes around within data[] */
   int rc;         /* The return code */
@@ -48741,7 +50379,7 @@
   hdr = pPage->hdrOffset;
   testcase( pc==get2byte(&data[hdr+5]) );
   testcase( pc+sz==pPage->pBt->usableSize );
-  if( pc < get2byte(&data[hdr+5]) || pc+sz > pPage->pBt->usableSize ){
+  if( pc < (u32)get2byte(&data[hdr+5]) || pc+sz > pPage->pBt->usableSize ){
     *pRC = SQLITE_CORRUPT_BKPT;
     return;
   }
@@ -48798,7 +50436,7 @@
   if( *pRC ) return;
 
   assert( i>=0 && i<=pPage->nCell+pPage->nOverflow );
-  assert( pPage->nCell<=MX_CELL(pPage->pBt) && MX_CELL(pPage->pBt)<=5460 );
+  assert( pPage->nCell<=MX_CELL(pPage->pBt) && MX_CELL(pPage->pBt)<=10921 );
   assert( pPage->nOverflow<=ArraySize(pPage->aOvfl) );
   assert( sqlite3_mutex_held(pPage->pBt->mutex) );
   /* The cell should normally be sized correctly.  However, when moving a
@@ -48878,12 +50516,12 @@
 
   assert( pPage->nOverflow==0 );
   assert( sqlite3_mutex_held(pPage->pBt->mutex) );
-  assert( nCell>=0 && nCell<=MX_CELL(pPage->pBt) && MX_CELL(pPage->pBt)<=5460 );
+  assert( nCell>=0 && nCell<=MX_CELL(pPage->pBt) && MX_CELL(pPage->pBt)<=10921);
   assert( sqlite3PagerIswriteable(pPage->pDbPage) );
 
   /* Check that the page has just been zeroed by zeroPage() */
   assert( pPage->nCell==0 );
-  assert( get2byte(&data[hdr+5])==nUsable );
+  assert( get2byteNotZero(&data[hdr+5])==nUsable );
 
   pCellptr = &data[pPage->cellOffset + nCell*2];
   cellbody = nUsable;
@@ -48949,6 +50587,7 @@
   assert( sqlite3PagerIswriteable(pParent->pDbPage) );
   assert( pPage->nOverflow==1 );
 
+  /* This error condition is now caught prior to reaching this function */
   if( pPage->nCell<=0 ) return SQLITE_CORRUPT_BKPT;
 
   /* Allocate a new page. This page will become the right-sibling of 
@@ -49278,7 +50917,7 @@
       ** is allocated.  */
       if( pBt->secureDelete ){
         int iOff = SQLITE_PTR_TO_INT(apDiv[i]) - SQLITE_PTR_TO_INT(pParent->aData);
-        if( (iOff+szNew[i])>pBt->usableSize ){
+        if( (iOff+szNew[i])>(int)pBt->usableSize ){
           rc = SQLITE_CORRUPT_BKPT;
           memset(apOld, 0, (i+1)*sizeof(MemPage*));
           goto balance_cleanup;
@@ -49357,7 +50996,7 @@
       szCell[nCell] = sz;
       pTemp = &aSpace1[iSpace1];
       iSpace1 += sz;
-      assert( sz<=pBt->pageSize/4 );
+      assert( sz<=pBt->maxLocal+23 );
       assert( iSpace1<=pBt->pageSize );
       memcpy(pTemp, apDiv[i], sz);
       apCell[nCell] = pTemp+leafCorrection;
@@ -49603,7 +51242,7 @@
         }
       }
       iOvflSpace += sz;
-      assert( sz<=pBt->pageSize/4 );
+      assert( sz<=pBt->maxLocal+23 );
       assert( iOvflSpace<=pBt->pageSize );
       insertCell(pParent, nxDiv, pCell, sz, pTemp, pNew->pgno, &rc);
       if( rc!=SQLITE_OK ) goto balance_cleanup;
@@ -50240,11 +51879,12 @@
 **     BTREE_INTKEY|BTREE_LEAFDATA     Used for SQL tables with rowid keys
 **     BTREE_ZERODATA                  Used for SQL indices
 */
-static int btreeCreateTable(Btree *p, int *piTable, int flags){
+static int btreeCreateTable(Btree *p, int *piTable, int createTabFlags){
   BtShared *pBt = p->pBt;
   MemPage *pRoot;
   Pgno pgnoRoot;
   int rc;
+  int ptfFlags;          /* Page-type flage for the root page of new table */
 
   assert( sqlite3BtreeHoldsMutex(p) );
   assert( pBt->inTransaction==TRANS_WRITE );
@@ -50363,8 +52003,14 @@
   }
 #endif
   assert( sqlite3PagerIswriteable(pRoot->pDbPage) );
-  zeroPage(pRoot, flags | PTF_LEAF);
+  if( createTabFlags & BTREE_INTKEY ){
+    ptfFlags = PTF_INTKEY | PTF_LEAFDATA | PTF_LEAF;
+  }else{
+    ptfFlags = PTF_ZERODATA | PTF_LEAF;
+  }
+  zeroPage(pRoot, ptfFlags);
   sqlite3PagerUnref(pRoot->pDbPage);
+  assert( (pBt->openFlags & BTREE_SINGLE)==0 || pgnoRoot==2 );
   *piTable = (int)pgnoRoot;
   return SQLITE_OK;
 }
@@ -50847,7 +52493,7 @@
         checkPtrmap(pCheck, iPage, PTRMAP_FREEPAGE, 0, zContext);
       }
 #endif
-      if( n>pCheck->pBt->usableSize/4-2 ){
+      if( n>(int)pCheck->pBt->usableSize/4-2 ){
         checkAppendMsg(pCheck, zContext,
            "freelist leaf count too big on page %d", iPage);
         N--;
@@ -51058,7 +52704,7 @@
   if( hit==0 ){
     pCheck->mallocFailed = 1;
   }else{
-    u16 contentOffset = get2byte(&data[hdr+5]);
+    int contentOffset = get2byteNotZero(&data[hdr+5]);
     assert( contentOffset<=usableSize );  /* Enforced by btreeInitPage() */
     memset(hit+contentOffset, 0, usableSize-contentOffset);
     memset(hit, 1, contentOffset);
@@ -51066,12 +52712,12 @@
     cellStart = hdr + 12 - 4*pPage->leaf;
     for(i=0; i<nCell; i++){
       int pc = get2byte(&data[cellStart+i*2]);
-      u16 size = 1024;
+      u32 size = 65536;
       int j;
       if( pc<=usableSize-4 ){
         size = cellSizePtr(pPage, &data[pc]);
       }
-      if( (pc+size-1)>=usableSize ){
+      if( (int)(pc+size-1)>=usableSize ){
         checkAppendMsg(pCheck, 0, 
             "Corruption detected in cell %d on page %d",i,iPage);
       }else{
@@ -51164,6 +52810,7 @@
     sCheck.anRef[i] = 1;
   }
   sqlite3StrAccumInit(&sCheck.errMsg, zErr, sizeof(zErr), 20000);
+  sCheck.errMsg.useMalloc = 2;
 
   /* Check the integrity of the freelist
   */
@@ -51262,6 +52909,29 @@
   return (p && (p->inTrans==TRANS_WRITE));
 }
 
+#ifndef SQLITE_OMIT_WAL
+/*
+** Run a checkpoint on the Btree passed as the first argument.
+**
+** Return SQLITE_LOCKED if this or any other connection has an open 
+** transaction on the shared-cache the argument Btree is connected to.
+*/
+SQLITE_PRIVATE int sqlite3BtreeCheckpoint(Btree *p){
+  int rc = SQLITE_OK;
+  if( p ){
+    BtShared *pBt = p->pBt;
+    sqlite3BtreeEnter(p);
+    if( pBt->inTransaction!=TRANS_NONE ){
+      rc = SQLITE_LOCKED;
+    }else{
+      rc = sqlite3PagerCheckpoint(pBt->pPager);
+    }
+    sqlite3BtreeLeave(p);
+  }
+  return rc;
+}
+#endif
+
 /*
 ** Return non-zero if a read (or write) transaction is active.
 */
@@ -51301,7 +52971,7 @@
   BtShared *pBt = p->pBt;
   sqlite3BtreeEnter(p);
   if( !pBt->pSchema && nBytes ){
-    pBt->pSchema = sqlite3MallocZero(nBytes);
+    pBt->pSchema = sqlite3DbMallocZero(0, nBytes);
     pBt->xFreeSchema = xFree;
   }
   sqlite3BtreeLeave(p);
@@ -51600,7 +53270,10 @@
     );
     p = 0;
   }else {
-    /* Allocate space for a new sqlite3_backup object */
+    /* Allocate space for a new sqlite3_backup object...
+    ** EVIDENCE-OF: R-64852-21591 The sqlite3_backup object is created by a
+    ** call to sqlite3_backup_init() and is destroyed by a call to
+    ** sqlite3_backup_finish(). */
     p = (sqlite3_backup *)sqlite3_malloc(sizeof(sqlite3_backup));
     if( !p ){
       sqlite3Error(pDestDb, SQLITE_NOMEM, 0);
@@ -51671,6 +53344,15 @@
     rc = SQLITE_READONLY;
   }
 
+#ifdef SQLITE_HAS_CODEC
+  /* Backup is not possible if the page size of the destination is changing
+  ** a a codec is in use.
+  */
+  if( nSrcPgsz!=nDestPgsz && sqlite3PagerGetCodec(pDestPager)!=0 ){
+    rc = SQLITE_READONLY;
+  }
+#endif
+
   /* This loop runs once for each destination page spanned by the source 
   ** page. For each iteration, variable iOff is set to the byte offset
   ** of the destination page.
@@ -51974,6 +53656,9 @@
   }
   sqlite3BtreeLeave(p->pSrc);
   if( p->pDestDb ){
+    /* EVIDENCE-OF: R-64852-21591 The sqlite3_backup object is created by a
+    ** call to sqlite3_backup_init() and is destroyed by a call to
+    ** sqlite3_backup_finish(). */
     sqlite3_free(p);
   }
   sqlite3_mutex_leave(mutex);
@@ -52225,6 +53910,9 @@
     pMem->z[pMem->n] = 0;
     pMem->z[pMem->n+1] = 0;
     pMem->flags |= MEM_Term;
+#ifdef SQLITE_DEBUG
+    pMem->pScopyFrom = 0;
+#endif
   }
 
   return SQLITE_OK;
@@ -52345,7 +54033,7 @@
     ctx.s.db = pMem->db;
     ctx.pMem = pMem;
     ctx.pFunc = pFunc;
-    pFunc->xFinalize(&ctx);
+    pFunc->xFinalize(&ctx); /* IMP: R-24505-23230 */
     assert( 0==(pMem->flags&MEM_Dyn) && !pMem->xDel );
     sqlite3DbFree(pMem->db, pMem->zMalloc);
     memcpy(pMem, &ctx.s, sizeof(ctx.s));
@@ -52686,6 +54374,28 @@
   return 0; 
 }
 
+#ifdef SQLITE_DEBUG
+/*
+** This routine prepares a memory cell for modication by breaking
+** its link to a shallow copy and by marking any current shallow
+** copies of this cell as invalid.
+**
+** This is used for testing and debugging only - to make sure shallow
+** copies are not misused.
+*/
+SQLITE_PRIVATE void sqlite3VdbeMemPrepareToChange(Vdbe *pVdbe, Mem *pMem){
+  int i;
+  Mem *pX;
+  for(i=1, pX=&pVdbe->aMem[1]; i<=pVdbe->nMem; i++, pX++){
+    if( pX->pScopyFrom==pMem ){
+      pX->flags |= MEM_Invalid;
+      pX->pScopyFrom = 0;
+    }
+  }
+  pMem->pScopyFrom = 0;
+}
+#endif /* SQLITE_DEBUG */
+
 /*
 ** Size of struct Mem not including the Mem.zMalloc member.
 */
@@ -53054,7 +54764,7 @@
         return 0;
       }
     }
-    sqlite3VdbeMemNulTerminate(pVal);
+    sqlite3VdbeMemNulTerminate(pVal); /* IMP: R-59893-45467 */
   }else{
     assert( (pVal->flags&MEM_Blob)==0 );
     sqlite3VdbeMemStringify(pVal, enc);
@@ -53109,7 +54819,7 @@
   }
   op = pExpr->op;
 
-  /* op can only be TK_REGISTER is we have compiled with SQLITE_ENABLE_STAT2.
+  /* op can only be TK_REGISTER if we have compiled with SQLITE_ENABLE_STAT2.
   ** The ifdef here is to enable us to achieve 100% branch test coverage even
   ** when SQLITE_ENABLE_STAT2 is omitted.
   */
@@ -53787,15 +55497,17 @@
   }
 }
 
+static void vdbeFreeOpArray(sqlite3 *, Op *, int);
+
 /*
 ** Delete a P4 value if necessary.
 */
 static void freeP4(sqlite3 *db, int p4type, void *p4){
   if( p4 ){
+    assert( db );
     switch( p4type ){
       case P4_REAL:
       case P4_INT64:
-      case P4_MPRINTF:
       case P4_DYNAMIC:
       case P4_KEYINFO:
       case P4_INTARRAY:
@@ -53803,10 +55515,14 @@
         sqlite3DbFree(db, p4);
         break;
       }
+      case P4_MPRINTF: {
+        if( db->pnBytesFreed==0 ) sqlite3_free(p4);
+        break;
+      }
       case P4_VDBEFUNC: {
         VdbeFunc *pVdbeFunc = (VdbeFunc *)p4;
         freeEphemeralFunction(db, pVdbeFunc->pFunc);
-        sqlite3VdbeDeleteAuxData(pVdbeFunc, 0);
+        if( db->pnBytesFreed==0 ) sqlite3VdbeDeleteAuxData(pVdbeFunc, 0);
         sqlite3DbFree(db, pVdbeFunc);
         break;
       }
@@ -53815,15 +55531,17 @@
         break;
       }
       case P4_MEM: {
-        sqlite3ValueFree((sqlite3_value*)p4);
+        if( db->pnBytesFreed==0 ){
+          sqlite3ValueFree((sqlite3_value*)p4);
+        }else{
+          Mem *p = (Mem*)p4;
+          sqlite3DbFree(db, p->zMalloc);
+          sqlite3DbFree(db, p);
+        }
         break;
       }
       case P4_VTAB : {
-        sqlite3VtabUnlock((VTable *)p4);
-        break;
-      }
-      case P4_SUBPROGRAM : {
-        sqlite3VdbeProgramDelete(db, (SubProgram *)p4, 1);
+        if( db->pnBytesFreed==0 ) sqlite3VtabUnlock((VTable *)p4);
         break;
       }
     }
@@ -53849,35 +55567,15 @@
 }
 
 /*
-** Decrement the ref-count on the SubProgram structure passed as the
-** second argument. If the ref-count reaches zero, free the structure.
-**
-** The array of VDBE opcodes stored as SubProgram.aOp is freed if
-** either the ref-count reaches zero or parameter freeop is non-zero.
-**
-** Since the array of opcodes pointed to by SubProgram.aOp may directly
-** or indirectly contain a reference to the SubProgram structure itself.
-** By passing a non-zero freeop parameter, the caller may ensure that all
-** SubProgram structures and their aOp arrays are freed, even when there
-** are such circular references.
+** Link the SubProgram object passed as the second argument into the linked
+** list at Vdbe.pSubProgram. This list is used to delete all sub-program
+** objects when the VM is no longer required.
 */
-SQLITE_PRIVATE void sqlite3VdbeProgramDelete(sqlite3 *db, SubProgram *p, int freeop){
-  if( p ){
-    assert( p->nRef>0 );
-    if( freeop || p->nRef==1 ){
-      Op *aOp = p->aOp;
-      p->aOp = 0;
-      vdbeFreeOpArray(db, aOp, p->nOp);
-      p->nOp = 0;
-    }
-    p->nRef--;
-    if( p->nRef==0 ){
-      sqlite3DbFree(db, p);
-    }
-  }
+SQLITE_PRIVATE void sqlite3VdbeLinkSubProgram(Vdbe *pVdbe, SubProgram *p){
+  p->pNext = pVdbe->pProgram;
+  pVdbe->pProgram = p;
 }
 
-
 /*
 ** Change N opcodes starting at addr to No-ops.
 */
@@ -53953,7 +55651,7 @@
 
     nField = ((KeyInfo*)zP4)->nField;
     nByte = sizeof(*pKeyInfo) + (nField-1)*sizeof(pKeyInfo->aColl[0]) + nField;
-    pKeyInfo = sqlite3Malloc( nByte );
+    pKeyInfo = sqlite3DbMallocRaw(0, nByte);
     pOp->p4.pKeyInfo = pKeyInfo;
     if( pKeyInfo ){
       u8 *aSortOrder;
@@ -54217,6 +55915,12 @@
     Mem *pEnd;
     sqlite3 *db = p->db;
     u8 malloc_failed = db->mallocFailed;
+    if( db->pnBytesFreed ){
+      for(pEnd=&p[N]; p<pEnd; p++){
+        sqlite3DbFree(db, p->zMalloc);
+      }
+      return;
+    }
     for(pEnd=&p[N]; p<pEnd; p++){
       assert( (&p[1])==pEnd || p[0].db==p[1].db );
 
@@ -54866,9 +56570,6 @@
   ** to the transaction.
   */
   rc = sqlite3VtabSync(db, &p->zErrMsg);
-  if( rc!=SQLITE_OK ){
-    return rc;
-  }
 
   /* This loop determines (a) if the commit hook should be invoked and
   ** (b) how many database files have open write transactions, not 
@@ -54876,13 +56577,17 @@
   ** one database file has an open write transaction, a master journal
   ** file is required for an atomic commit.
   */ 
-  for(i=0; i<db->nDb; i++){ 
+  for(i=0; rc==SQLITE_OK && i<db->nDb; i++){ 
     Btree *pBt = db->aDb[i].pBt;
     if( sqlite3BtreeIsInTrans(pBt) ){
       needXcommit = 1;
       if( i!=1 ) nTrans++;
+      rc = sqlite3PagerExclusiveLock(sqlite3BtreePager(pBt));
     }
   }
+  if( rc!=SQLITE_OK ){
+    return rc;
+  }
 
   /* If there are any write-transactions at all, invoke the commit hook */
   if( needXcommit && db->xCommitCallback ){
@@ -54974,9 +56679,10 @@
       Btree *pBt = db->aDb[i].pBt;
       if( sqlite3BtreeIsInTrans(pBt) ){
         char const *zFile = sqlite3BtreeGetJournalname(pBt);
-        if( zFile==0 || zFile[0]==0 ){
+        if( zFile==0 ){
           continue;  /* Ignore TEMP and :memory: databases */
         }
+        assert( zFile[0]!=0 );
         if( !needSync && !sqlite3BtreeSyncDisabled(pBt) ){
           needSync = 1;
         }
@@ -55021,6 +56727,7 @@
       }
     }
     sqlite3OsCloseFree(pMaster);
+    assert( rc!=SQLITE_BUSY );
     if( rc!=SQLITE_OK ){
       sqlite3DbFree(db, zMaster);
       return rc;
@@ -55279,8 +56986,17 @@
     isSpecialError = mrc==SQLITE_NOMEM || mrc==SQLITE_IOERR
                      || mrc==SQLITE_INTERRUPT || mrc==SQLITE_FULL;
     if( isSpecialError ){
-      /* If the query was read-only, we need do no rollback at all. Otherwise,
-      ** proceed with the special handling.
+      /* If the query was read-only and the error code is SQLITE_INTERRUPT, 
+      ** no rollback is necessary. Otherwise, at least a savepoint 
+      ** transaction must be rolled back to restore the database to a 
+      ** consistent state.
+      **
+      ** Even if the statement is read-only, it is important to perform
+      ** a statement or transaction rollback operation. If the error 
+      ** occured while writing to the journal, sub-journal or database
+      ** file as part of an effort to free up cache space (see function
+      ** pagerStress() in pager.c), the rollback is required to restore 
+      ** the pager to a consistent state.
       */
       if( !p->readOnly || mrc!=SQLITE_INTERRUPT ){
         if( (mrc==SQLITE_NOMEM || mrc==SQLITE_FULL) && p->usesStmtJournal ){
@@ -55550,6 +57266,30 @@
 }
 
 /*
+** Free all memory associated with the Vdbe passed as the second argument.
+** The difference between this function and sqlite3VdbeDelete() is that
+** VdbeDelete() also unlinks the Vdbe from the list of VMs associated with
+** the database connection.
+*/
+SQLITE_PRIVATE void sqlite3VdbeDeleteObject(sqlite3 *db, Vdbe *p){
+  SubProgram *pSub, *pNext;
+  assert( p->db==0 || p->db==db );
+  releaseMemArray(p->aVar, p->nVar);
+  releaseMemArray(p->aColName, p->nResColumn*COLNAME_N);
+  for(pSub=p->pProgram; pSub; pSub=pNext){
+    pNext = pSub->pNext;
+    vdbeFreeOpArray(db, pSub->aOp, pSub->nOp);
+    sqlite3DbFree(db, pSub);
+  }
+  vdbeFreeOpArray(db, p->aOp, p->nOp);
+  sqlite3DbFree(db, p->aLabel);
+  sqlite3DbFree(db, p->aColName);
+  sqlite3DbFree(db, p->zSql);
+  sqlite3DbFree(db, p->pFree);
+  sqlite3DbFree(db, p);
+}
+
+/*
 ** Delete an entire VDBE.
 */
 SQLITE_PRIVATE void sqlite3VdbeDelete(Vdbe *p){
@@ -55566,16 +57306,9 @@
   if( p->pNext ){
     p->pNext->pPrev = p->pPrev;
   }
-  releaseMemArray(p->aVar, p->nVar);
-  releaseMemArray(p->aColName, p->nResColumn*COLNAME_N);
-  vdbeFreeOpArray(db, p->aOp, p->nOp);
-  sqlite3DbFree(db, p->aLabel);
-  sqlite3DbFree(db, p->aColName);
-  sqlite3DbFree(db, p->zSql);
   p->magic = VDBE_MAGIC_DEAD;
-  sqlite3DbFree(db, p->pFree);
   p->db = 0;
-  sqlite3DbFree(db, p);
+  sqlite3VdbeDeleteObject(db, p);
 }
 
 /*
@@ -55601,11 +57334,8 @@
     rc = sqlite3BtreeMovetoUnpacked(p->pCursor, 0, p->movetoTarget, 0, &res);
     if( rc ) return rc;
     p->lastRowid = p->movetoTarget;
-    p->rowidIsValid = ALWAYS(res==0) ?1:0;
-    if( NEVER(res<0) ){
-      rc = sqlite3BtreeNext(p->pCursor, &res);
-      if( rc ) return rc;
-    }
+    if( res!=0 ) return SQLITE_CORRUPT_BKPT;
+    p->rowidIsValid = 1;
 #ifdef SQLITE_TEST
     sqlite3_search_count++;
 #endif
@@ -56492,7 +58222,7 @@
     sqlite3VdbeMemExpandBlob(p);
     p->flags &= ~MEM_Str;
     p->flags |= MEM_Blob;
-    return p->z;
+    return p->n ? p->z : 0;
   }else{
     return sqlite3_value_text(pVal);
   }
@@ -56749,7 +58479,7 @@
   if( rc!=SQLITE_ROW && db->xProfile && !db->init.busy && p->zSql ){
     sqlite3_int64 iNow;
     sqlite3OsCurrentTimeInt64(db->pVfs, &iNow);
-    db->xProfile(db->pProfileArg, p->zSql, iNow - p->startTime);
+    db->xProfile(db->pProfileArg, p->zSql, (iNow - p->startTime)*1000000);
   }
 #endif
 
@@ -56846,6 +58576,12 @@
 /*
 ** Extract the user data from a sqlite3_context structure and return a
 ** pointer to it.
+**
+** IMPLEMENTATION-OF: R-46798-50301 The sqlite3_context_db_handle() interface
+** returns a copy of the pointer to the database connection (the 1st
+** parameter) of the sqlite3_create_function() and
+** sqlite3_create_function16() routines that originally registered the
+** application defined function.
 */
 SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context *p){
   assert( p && p->pFunc );
@@ -57055,8 +58791,7 @@
 **     sqlite3_column_real()
 **     sqlite3_column_bytes()
 **     sqlite3_column_bytes16()
-**
-** But not for sqlite3_column_blob(), which never calls malloc().
+**     sqiite3_column_blob()
 */
 static void columnMallocFailure(sqlite3_stmt *pStmt)
 {
@@ -57324,6 +59059,12 @@
 
   /* If the bit corresponding to this variable in Vdbe.expmask is set, then 
   ** binding a new value to this variable invalidates the current query plan.
+  **
+  ** IMPLEMENTATION-OF: R-48440-37595 If the specific value bound to host
+  ** parameter in the WHERE clause might influence the choice of query plan
+  ** for a statement, then the statement will be automatically recompiled,
+  ** as if there had been a schema change, on the first sqlite3_step() call
+  ** following any change to the bindings of that parameter.
   */
   if( p->isPrepareV2 &&
      ((i<32 && p->expmask & ((u32)1 << i)) || p->expmask==0xffffffff)
@@ -57822,6 +59563,17 @@
 */
 
 /*
+** Invoke this macro on memory cells just prior to changing the
+** value of the cell.  This macro verifies that shallow copies are
+** not misused.
+*/
+#ifdef SQLITE_DEBUG
+# define memAboutToChange(P,M) sqlite3VdbeMemPrepareToChange(P,M)
+#else
+# define memAboutToChange(P,M)
+#endif
+
+/*
 ** The following global variable is incremented every time a cursor
 ** moves, either by the OP_SeekXX, OP_Next, or OP_Prev opcodes.  The test
 ** procedures use this information to make sure that indices are
@@ -58366,6 +60118,20 @@
 #endif
 
 /*
+** Transfer error message text from an sqlite3_vtab.zErrMsg (text stored
+** in memory obtained from sqlite3_malloc) into a Vdbe.zErrMsg (text stored
+** in memory obtained from sqlite3DbMalloc).
+*/
+static void importVtabErrMsg(Vdbe *p, sqlite3_vtab *pVtab){
+  sqlite3 *db = p->db;
+  sqlite3DbFree(db, p->zErrMsg);
+  p->zErrMsg = sqlite3DbStrDup(db, pVtab->zErrMsg);
+  sqlite3_free(pVtab->zErrMsg);
+  pVtab->zErrMsg = 0;
+}
+
+
+/*
 ** Execute as much of a VDBE program as we can then return.
 **
 ** sqlite3VdbeMakeReady() must be called before this routine in order to
@@ -58916,6 +60682,7 @@
       assert( pOp->p2>0 );
       assert( pOp->p2<=p->nMem );
       pOut = &aMem[pOp->p2];
+      memAboutToChange(p, pOut);
       sqlite3VdbeMemReleaseExternal(pOut);
       pOut->flags = MEM_Int;
     }
@@ -58925,25 +60692,30 @@
     if( (pOp->opflags & OPFLG_IN1)!=0 ){
       assert( pOp->p1>0 );
       assert( pOp->p1<=p->nMem );
+      assert( memIsValid(&aMem[pOp->p1]) );
       REGISTER_TRACE(pOp->p1, &aMem[pOp->p1]);
     }
     if( (pOp->opflags & OPFLG_IN2)!=0 ){
       assert( pOp->p2>0 );
       assert( pOp->p2<=p->nMem );
+      assert( memIsValid(&aMem[pOp->p2]) );
       REGISTER_TRACE(pOp->p2, &aMem[pOp->p2]);
     }
     if( (pOp->opflags & OPFLG_IN3)!=0 ){
       assert( pOp->p3>0 );
       assert( pOp->p3<=p->nMem );
+      assert( memIsValid(&aMem[pOp->p3]) );
       REGISTER_TRACE(pOp->p3, &aMem[pOp->p3]);
     }
     if( (pOp->opflags & OPFLG_OUT2)!=0 ){
       assert( pOp->p2>0 );
       assert( pOp->p2<=p->nMem );
+      memAboutToChange(p, &aMem[pOp->p2]);
     }
     if( (pOp->opflags & OPFLG_OUT3)!=0 ){
       assert( pOp->p3>0 );
       assert( pOp->p3<=p->nMem );
+      memAboutToChange(p, &aMem[pOp->p3]);
     }
 #endif
   
@@ -59005,6 +60777,7 @@
 case OP_Gosub: {            /* jump, in1 */
   pIn1 = &aMem[pOp->p1];
   assert( (pIn1->flags & MEM_Dyn)==0 );
+  memAboutToChange(p, pIn1);
   pIn1->flags = MEM_Int;
   pIn1->u.i = pc;
   REGISTER_TRACE(pOp->p1, pIn1);
@@ -59212,11 +60985,7 @@
 /* Opcode: Blob P1 P2 * P4
 **
 ** P4 points to a blob of data P1 bytes long.  Store this
-** blob in register P2. This instruction is not coded directly
-** by the compiler. Instead, the compiler layer specifies
-** an OP_HexBlob opcode, with the hex string representation of
-** the blob as P4. This opcode is transformed to an OP_Blob
-** the first time it is executed.
+** blob in register P2.
 */
 case OP_Blob: {                /* out2-prerelease */
   assert( pOp->p1 <= SQLITE_MAX_LENGTH );
@@ -59274,6 +61043,8 @@
   while( u.ac.n-- ){
     assert( pOut<=&aMem[p->nMem] );
     assert( pIn1<=&aMem[p->nMem] );
+    assert( memIsValid(pIn1) );
+    memAboutToChange(p, pOut);
     u.ac.zMalloc = pOut->zMalloc;
     pOut->zMalloc = 0;
     sqlite3VdbeMemMove(pOut, pIn1);
@@ -59319,6 +61090,9 @@
   pOut = &aMem[pOp->p2];
   assert( pOut!=pIn1 );
   sqlite3VdbeMemShallowCopy(pOut, pIn1, MEM_Ephem);
+#ifdef SQLITE_DEBUG
+  if( pOut->pScopyFrom==0 ) pOut->pScopyFrom = pIn1;
+#endif
   REGISTER_TRACE(pOp->p2, pOut);
   break;
 }
@@ -59379,6 +61153,10 @@
   */
   u.ad.pMem = p->pResultSet = &aMem[pOp->p1];
   for(u.ad.i=0; u.ad.i<pOp->p2; u.ad.i++){
+    assert( memIsValid(&u.ad.pMem[u.ad.i]) );
+    Deephemeralize(&u.ad.pMem[u.ad.i]);
+    assert( (u.ad.pMem[u.ad.i].flags & MEM_Ephem)==0
+            || (u.ad.pMem[u.ad.i].flags & (MEM_Str|MEM_Blob))==0 );
     sqlite3VdbeMemNulTerminate(&u.ad.pMem[u.ad.i]);
     sqlite3VdbeMemStoreType(&u.ad.pMem[u.ad.i]);
     REGISTER_TRACE(pOp->p1+u.ad.i, &u.ad.pMem[u.ad.i]);
@@ -59610,12 +61388,17 @@
   u.ag.n = pOp->p5;
   u.ag.apVal = p->apArg;
   assert( u.ag.apVal || u.ag.n==0 );
+  assert( pOp->p3>0 && pOp->p3<=p->nMem );
+  pOut = &aMem[pOp->p3];
+  memAboutToChange(p, pOut);
 
   assert( u.ag.n==0 || (pOp->p2>0 && pOp->p2+u.ag.n<=p->nMem+1) );
   assert( pOp->p3<pOp->p2 || pOp->p3>=pOp->p2+u.ag.n );
   u.ag.pArg = &aMem[pOp->p2];
   for(u.ag.i=0; u.ag.i<u.ag.n; u.ag.i++, u.ag.pArg++){
+    assert( memIsValid(u.ag.pArg) );
     u.ag.apVal[u.ag.i] = u.ag.pArg;
+    Deephemeralize(u.ag.pArg);
     sqlite3VdbeMemStoreType(u.ag.pArg);
     REGISTER_TRACE(pOp->p2+u.ag.i, u.ag.pArg);
   }
@@ -59629,8 +61412,6 @@
     u.ag.ctx.pFunc = u.ag.ctx.pVdbeFunc->pFunc;
   }
 
-  assert( pOp->p3>0 && pOp->p3<=p->nMem );
-  pOut = &aMem[pOp->p3];
   u.ag.ctx.s.flags = MEM_Null;
   u.ag.ctx.s.db = db;
   u.ag.ctx.s.xDel = 0;
@@ -59650,7 +61431,7 @@
     assert( pOp[-1].opcode==OP_CollSeq );
     u.ag.ctx.pColl = pOp[-1].p4.pColl;
   }
-  (*u.ag.ctx.pFunc->xFunc)(&u.ag.ctx, u.ag.n, u.ag.apVal);
+  (*u.ag.ctx.pFunc->xFunc)(&u.ag.ctx, u.ag.n, u.ag.apVal); /* IMP: R-24505-23230 */
   if( db->mallocFailed ){
     /* Even though a malloc() has failed, the implementation of the
     ** user function may have called an sqlite3_result_XXX() function
@@ -59702,7 +61483,7 @@
 /* Opcode: ShiftLeft P1 P2 P3 * *
 **
 ** Shift the integer value in register P2 to the left by the
-** number of bits specified by the integer in regiser P1.
+** number of bits specified by the integer in register P1.
 ** Store the result in register P3.
 ** If either input is NULL, the result is NULL.
 */
@@ -59752,6 +61533,7 @@
 */
 case OP_AddImm: {            /* in1 */
   pIn1 = &aMem[pOp->p1];
+  memAboutToChange(p, pIn1);
   sqlite3VdbeMemIntegerify(pIn1);
   pIn1->u.i += pOp->p2;
   break;
@@ -59766,6 +61548,7 @@
 */
 case OP_MustBeInt: {            /* jump, in1 */
   pIn1 = &aMem[pOp->p1];
+  memAboutToChange(p, pIn1);
   applyAffinity(pIn1, SQLITE_AFF_NUMERIC, encoding);
   if( (pIn1->flags & MEM_Int)==0 ){
     if( pOp->p2==0 ){
@@ -59792,6 +61575,7 @@
 */
 case OP_RealAffinity: {                  /* in1 */
   pIn1 = &aMem[pOp->p1];
+  memAboutToChange(p, pIn1);
   if( pIn1->flags & MEM_Int ){
     sqlite3VdbeMemRealify(pIn1);
   }
@@ -59811,6 +61595,7 @@
 */
 case OP_ToText: {                  /* same as TK_TO_TEXT, in1 */
   pIn1 = &aMem[pOp->p1];
+  memAboutToChange(p, pIn1);
   if( pIn1->flags & MEM_Null ) break;
   assert( MEM_Str==(MEM_Blob>>3) );
   pIn1->flags |= (pIn1->flags&MEM_Blob)>>3;
@@ -59833,6 +61618,7 @@
 */
 case OP_ToBlob: {                  /* same as TK_TO_BLOB, in1 */
   pIn1 = &aMem[pOp->p1];
+  memAboutToChange(p, pIn1);
   if( pIn1->flags & MEM_Null ) break;
   if( (pIn1->flags & MEM_Blob)==0 ){
     applyAffinity(pIn1, SQLITE_AFF_TEXT, encoding);
@@ -59857,6 +61643,7 @@
 */
 case OP_ToNumeric: {                  /* same as TK_TO_NUMERIC, in1 */
   pIn1 = &aMem[pOp->p1];
+  memAboutToChange(p, pIn1);
   if( (pIn1->flags & (MEM_Null|MEM_Int|MEM_Real))==0 ){
     sqlite3VdbeMemNumerify(pIn1);
   }
@@ -59866,7 +61653,7 @@
 
 /* Opcode: ToInt P1 * * * *
 **
-** Force the value in register P1 be an integer.  If
+** Force the value in register P1 to be an integer.  If
 ** The value is currently a real number, drop its fractional part.
 ** If the value is text or blob, try to convert it to an integer using the
 ** equivalent of atoi() and store 0 if no such conversion is possible.
@@ -59875,6 +61662,7 @@
 */
 case OP_ToInt: {                  /* same as TK_TO_INT, in1 */
   pIn1 = &aMem[pOp->p1];
+  memAboutToChange(p, pIn1);
   if( (pIn1->flags & MEM_Null)==0 ){
     sqlite3VdbeMemIntegerify(pIn1);
   }
@@ -59893,6 +61681,7 @@
 */
 case OP_ToReal: {                  /* same as TK_TO_REAL, in1 */
   pIn1 = &aMem[pOp->p1];
+  memAboutToChange(p, pIn1);
   if( (pIn1->flags & MEM_Null)==0 ){
     sqlite3VdbeMemRealify(pIn1);
   }
@@ -59907,7 +61696,7 @@
 **
 ** If the SQLITE_JUMPIFNULL bit of P5 is set and either reg(P1) or
 ** reg(P3) is NULL then take the jump.  If the SQLITE_JUMPIFNULL 
-** bit is clear then fall thru if either operand is NULL.
+** bit is clear then fall through if either operand is NULL.
 **
 ** The SQLITE_AFF_MASK portion of P5 must be an affinity character -
 ** SQLITE_AFF_TEXT, SQLITE_AFF_INTEGER, and so forth. An attempt is made 
@@ -59987,6 +61776,8 @@
 
   pIn1 = &aMem[pOp->p1];
   pIn3 = &aMem[pOp->p3];
+  memAboutToChange(p, pIn1);
+  memAboutToChange(p, pIn3);
   u.ai.flags1 = pIn1->flags;
   u.ai.flags3 = pIn3->flags;
   if( (pIn1->flags | pIn3->flags)&MEM_Null ){
@@ -60037,6 +61828,7 @@
 
   if( pOp->p5 & SQLITE_STOREP2 ){
     pOut = &aMem[pOp->p2];
+    memAboutToChange(p, pOut);
     MemSetTypeFlag(pOut, MEM_Int);
     pOut->u.i = u.ai.res;
     REGISTER_TRACE(pOp->p2, pOut);
@@ -60068,8 +61860,8 @@
 
 /* Opcode: Compare P1 P2 P3 P4 *
 **
-** Compare to vectors of registers in reg(P1)..reg(P1+P3-1) (all this
-** one "A") and in reg(P2)..reg(P2+P3-1) ("B").  Save the result of
+** Compare two vectors of registers in reg(P1)..reg(P1+P3-1) (call this
+** vector "A") and in reg(P2)..reg(P2+P3-1) ("B").  Save the result of
 ** the comparison for use by the next OP_Jump instruct.
 **
 ** P4 is a KeyInfo structure that defines collating sequences and sort
@@ -60111,6 +61903,8 @@
 #endif /* SQLITE_DEBUG */
   for(u.aj.i=0; u.aj.i<u.aj.n; u.aj.i++){
     u.aj.idx = aPermute ? aPermute[u.aj.i] : u.aj.i;
+    assert( memIsValid(&aMem[u.aj.p1+u.aj.idx]) );
+    assert( memIsValid(&aMem[u.aj.p2+u.aj.idx]) );
     REGISTER_TRACE(u.aj.p1+u.aj.idx, &aMem[u.aj.p1+u.aj.idx]);
     REGISTER_TRACE(u.aj.p2+u.aj.idx, &aMem[u.aj.p2+u.aj.idx]);
     assert( u.aj.i<u.aj.pKeyInfo->nField );
@@ -60342,6 +62136,7 @@
   assert( u.am.p1<p->nCursor );
   assert( pOp->p3>0 && pOp->p3<=p->nMem );
   u.am.pDest = &aMem[pOp->p3];
+  memAboutToChange(p, u.am.pDest);
   MemSetTypeFlag(u.am.pDest, MEM_Null);
   u.am.zRec = 0;
 
@@ -60389,6 +62184,7 @@
   }else if( u.am.pC->pseudoTableReg>0 ){
     u.am.pReg = &aMem[u.am.pC->pseudoTableReg];
     assert( u.am.pReg->flags & MEM_Blob );
+    assert( memIsValid(u.am.pReg) );
     u.am.payloadSize = u.am.pReg->n;
     u.am.zRec = u.am.pReg->z;
     u.am.pC->cacheStatus = (pOp->p5&OPFLAG_CLEARCACHE) ? CACHE_STALE : p->cacheCtr;
@@ -60613,6 +62409,8 @@
   pIn1 = &aMem[pOp->p1];
   while( (u.an.cAff = *(u.an.zAffinity++))!=0 ){
     assert( pIn1 <= &p->aMem[p->nMem] );
+    assert( memIsValid(pIn1) );
+    memAboutToChange(p, pIn1);
     ExpandBlob(pIn1);
     applyAffinity(pIn1, u.an.cAff, encoding);
     pIn1++;
@@ -60622,12 +62420,9 @@
 
 /* Opcode: MakeRecord P1 P2 P3 P4 *
 **
-** Convert P2 registers beginning with P1 into a single entry
-** suitable for use as a data record in a database table or as a key
-** in an index.  The details of the format are irrelevant as long as
-** the OP_Column opcode can decode the record later.
-** Refer to source code comments for the details of the record
-** format.
+** Convert P2 registers beginning with P1 into the [record format]
+** use as a data record in a database table or as a key
+** in an index.  The OP_Column opcode can decode the record later.
 **
 ** P4 may be a string that is P2 characters long.  The nth character of the
 ** string indicates the column affinity that should be used for the nth
@@ -60684,11 +62479,18 @@
   u.ao.pLast = &u.ao.pData0[u.ao.nField-1];
   u.ao.file_format = p->minWriteFileFormat;
 
+  /* Identify the output register */
+  assert( pOp->p3<pOp->p1 || pOp->p3>=pOp->p1+pOp->p2 );
+  pOut = &aMem[pOp->p3];
+  memAboutToChange(p, pOut);
+
   /* Loop through the elements that will make up the record to figure
   ** out how much space is required for the new record.
   */
   for(u.ao.pRec=u.ao.pData0; u.ao.pRec<=u.ao.pLast; u.ao.pRec++){
+    assert( memIsValid(u.ao.pRec) );
     if( u.ao.zAffinity ){
+      memAboutToChange(p, u.ao.pRec);
       applyAffinity(u.ao.pRec, u.ao.zAffinity[u.ao.pRec-u.ao.pData0], encoding);
     }
     if( u.ao.pRec->flags&MEM_Zero && u.ao.pRec->n>0 ){
@@ -60722,8 +62524,6 @@
   ** be one of the input registers (because the following call to
   ** sqlite3VdbeMemGrow() could clobber the value before it is used).
   */
-  assert( pOp->p3<pOp->p1 || pOp->p3>=pOp->p1+pOp->p2 );
-  pOut = &aMem[pOp->p3];
   if( sqlite3VdbeMemGrow(pOut, (int)u.ao.nByte, 0) ){
     goto no_mem;
   }
@@ -60896,6 +62696,7 @@
         if( u.aq.p1==SAVEPOINT_ROLLBACK && (db->flags&SQLITE_InternChanges)!=0 ){
           sqlite3ExpirePreparedStatements(db);
           sqlite3ResetInternalSchema(db, 0);
+          db->flags = (db->flags | SQLITE_InternChanges);
         }
       }
 
@@ -61286,6 +63087,8 @@
     assert( u.aw.p2>0 );
     assert( u.aw.p2<=p->nMem );
     pIn2 = &aMem[u.aw.p2];
+    assert( memIsValid(pIn2) );
+    assert( (pIn2->flags & MEM_Int)!=0 );
     sqlite3VdbeMemIntegerify(pIn2);
     u.aw.p2 = (int)pIn2->u.i;
     /* The u.aw.p2 value always comes from a prior OP_CreateTable opcode and
@@ -61308,6 +63111,7 @@
   u.aw.pCur = allocateCursor(p, pOp->p1, u.aw.nField, u.aw.iDb, 1);
   if( u.aw.pCur==0 ) goto no_mem;
   u.aw.pCur->nullRow = 1;
+  u.aw.pCur->isOrdered = 1;
   rc = sqlite3BtreeCursor(u.aw.pX, u.aw.p2, u.aw.wrFlag, u.aw.pKeyInfo, u.aw.pCur->pCursor);
   u.aw.pCur->pKeyInfo = u.aw.pKeyInfo;
 
@@ -61360,7 +63164,7 @@
 #if 0  /* local variables moved into u.ax */
   VdbeCursor *pCx;
 #endif /* local variables moved into u.ax */
-  static const int openFlags =
+  static const int vfsFlags =
       SQLITE_OPEN_READWRITE |
       SQLITE_OPEN_CREATE |
       SQLITE_OPEN_EXCLUSIVE |
@@ -61371,21 +63175,21 @@
   u.ax.pCx = allocateCursor(p, pOp->p1, pOp->p2, -1, 1);
   if( u.ax.pCx==0 ) goto no_mem;
   u.ax.pCx->nullRow = 1;
-  rc = sqlite3BtreeFactory(db, 0, 1, SQLITE_DEFAULT_TEMP_CACHE_SIZE, openFlags,
-                           &u.ax.pCx->pBt);
+  rc = sqlite3BtreeOpen(0, db, &u.ax.pCx->pBt,
+                        BTREE_OMIT_JOURNAL | BTREE_SINGLE | pOp->p5, vfsFlags);
   if( rc==SQLITE_OK ){
     rc = sqlite3BtreeBeginTrans(u.ax.pCx->pBt, 1);
   }
   if( rc==SQLITE_OK ){
     /* If a transient index is required, create it by calling
-    ** sqlite3BtreeCreateTable() with the BTREE_ZERODATA flag before
+    ** sqlite3BtreeCreateTable() with the BTREE_BLOBKEY flag before
     ** opening it. If a transient table is required, just use the
-    ** automatically created table with root-page 1 (an INTKEY table).
+    ** automatically created table with root-page 1 (an BLOB_INTKEY table).
     */
     if( pOp->p4.pKeyInfo ){
       int pgno;
       assert( pOp->p4type==P4_KEYINFO );
-      rc = sqlite3BtreeCreateTable(u.ax.pCx->pBt, &pgno, BTREE_ZERODATA);
+      rc = sqlite3BtreeCreateTable(u.ax.pCx->pBt, &pgno, BTREE_BLOBKEY);
       if( rc==SQLITE_OK ){
         assert( pgno==MASTER_ROOT+1 );
         rc = sqlite3BtreeCursor(u.ax.pCx->pBt, pgno, 1,
@@ -61399,6 +63203,7 @@
       u.ax.pCx->isTable = 1;
     }
   }
+  u.ax.pCx->isOrdered = (pOp->p5!=BTREE_UNORDERED);
   u.ax.pCx->isIndex = !u.ax.pCx->isTable;
   break;
 }
@@ -61518,6 +63323,7 @@
   assert( OP_SeekLe == OP_SeekLt+1 );
   assert( OP_SeekGe == OP_SeekLt+2 );
   assert( OP_SeekGt == OP_SeekLt+3 );
+  assert( u.az.pC->isOrdered );
   if( u.az.pC->pCursor!=0 ){
     u.az.oc = pOp->opcode;
     u.az.pC->nullRow = 0;
@@ -61600,6 +63406,9 @@
       assert( u.az.oc!=OP_SeekLt || u.az.r.flags==0 );
 
       u.az.r.aMem = &aMem[pOp->p3];
+#ifdef SQLITE_DEBUG
+      { int i; for(i=0; i<u.az.r.nField; i++) assert( memIsValid(&u.az.r.aMem[i]) ); }
+#endif
       ExpandBlob(u.az.r.aMem);
       rc = sqlite3BtreeMovetoUnpacked(u.az.pC->pCursor, &u.az.r, 0, 0, &u.az.res);
       if( rc!=SQLITE_OK ){
@@ -61728,11 +63537,14 @@
       u.bb.r.pKeyInfo = u.bb.pC->pKeyInfo;
       u.bb.r.nField = (u16)pOp->p4.i;
       u.bb.r.aMem = pIn3;
+#ifdef SQLITE_DEBUG
+      { int i; for(i=0; i<u.bb.r.nField; i++) assert( memIsValid(&u.bb.r.aMem[i]) ); }
+#endif
       u.bb.r.flags = UNPACKED_PREFIX_MATCH;
       u.bb.pIdxKey = &u.bb.r;
     }else{
       assert( pIn3->flags & MEM_Blob );
-      ExpandBlob(pIn3);
+      assert( (pIn3->flags & MEM_Zero)==0 );  /* zeroblobs already expanded */
       u.bb.pIdxKey = sqlite3VdbeRecordUnpack(u.bb.pC->pKeyInfo, pIn3->n, pIn3->z,
                                         u.bb.aTempRec, sizeof(u.bb.aTempRec));
       if( u.bb.pIdxKey==0 ){
@@ -61827,6 +63639,9 @@
     u.bc.r.nField = u.bc.nField + 1;
     u.bc.r.flags = UNPACKED_PREFIX_SEARCH;
     u.bc.r.aMem = u.bc.aMx;
+#ifdef SQLITE_DEBUG
+    { int i; for(i=0; i<u.bc.r.nField; i++) assert( memIsValid(&u.bc.r.aMem[i]) ); }
+#endif
 
     /* Extract the value of u.bc.R from register P3. */
     sqlite3VdbeMemIntegerify(pIn3);
@@ -61849,7 +63664,7 @@
 **
 ** Use the content of register P3 as a integer key.  If a record 
 ** with that key does not exist in table of P1, then jump to P2. 
-** If the record does exist, then fall thru.  The cursor is left 
+** If the record does exist, then fall through.  The cursor is left 
 ** pointing to the record if it exists.
 **
 ** The difference between this operation and NotFound is that this
@@ -62007,7 +63822,9 @@
           /* Assert that P3 is a valid memory cell. */
           assert( pOp->p3<=p->nMem );
           u.be.pMem = &aMem[pOp->p3];
+          memAboutToChange(p, u.be.pMem);
         }
+        assert( memIsValid(u.be.pMem) );
 
         REGISTER_TRACE(pOp->p3, u.be.pMem);
         sqlite3VdbeMemIntegerify(u.be.pMem);
@@ -62026,29 +63843,36 @@
       sqlite3BtreeSetCachedRowid(u.be.pC->pCursor, u.be.v<MAX_ROWID ? u.be.v+1 : 0);
     }
     if( u.be.pC->useRandomRowid ){
-      /* IMPLEMENTATION-OF: R-48598-02938 If the largest ROWID is equal to the
+      /* IMPLEMENTATION-OF: R-07677-41881 If the largest ROWID is equal to the
       ** largest possible integer (9223372036854775807) then the database
-      ** engine starts picking candidate ROWIDs at random until it finds one
-      ** that is not previously used.
-      */
+      ** engine starts picking positive candidate ROWIDs at random until
+      ** it finds one that is not previously used. */
       assert( pOp->p3==0 );  /* We cannot be in random rowid mode if this is
                              ** an AUTOINCREMENT table. */
+      /* on the first attempt, simply do one more than previous */
       u.be.v = db->lastRowid;
+      u.be.v &= (MAX_ROWID>>1); /* ensure doesn't go negative */
+      u.be.v++; /* ensure non-zero */
       u.be.cnt = 0;
-      do{
-        if( u.be.cnt==0 && (u.be.v&0xffffff)==u.be.v ){
-          u.be.v++;
+      while(   ((rc = sqlite3BtreeMovetoUnpacked(u.be.pC->pCursor, 0, (u64)u.be.v,
+                                                 0, &u.be.res))==SQLITE_OK)
+            && (u.be.res==0)
+            && (++u.be.cnt<100)){
+        /* collision - try another random rowid */
+        sqlite3_randomness(sizeof(u.be.v), &u.be.v);
+        if( u.be.cnt<5 ){
+          /* try "small" random rowids for the initial attempts */
+          u.be.v &= 0xffffff;
         }else{
-          sqlite3_randomness(sizeof(u.be.v), &u.be.v);
-          if( u.be.cnt<5 ) u.be.v &= 0xffffff;
+          u.be.v &= (MAX_ROWID>>1); /* ensure doesn't go negative */
         }
-        rc = sqlite3BtreeMovetoUnpacked(u.be.pC->pCursor, 0, (u64)u.be.v, 0, &u.be.res);
-        u.be.cnt++;
-      }while( u.be.cnt<100 && rc==SQLITE_OK && u.be.res==0 );
+        u.be.v++; /* ensure non-zero */
+      }
       if( rc==SQLITE_OK && u.be.res==0 ){
         rc = SQLITE_FULL;   /* IMP: R-38219-53002 */
         goto abort_due_to_error;
       }
+      assert( u.be.v>0 );  /* EV: R-40812-03570 */
     }
     u.be.pC->rowidIsValid = 0;
     u.be.pC->deferredMoveto = 0;
@@ -62118,6 +63942,7 @@
 
   u.bf.pData = &aMem[pOp->p2];
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
+  assert( memIsValid(u.bf.pData) );
   u.bf.pC = p->apCsr[pOp->p1];
   assert( u.bf.pC!=0 );
   assert( u.bf.pC->pCursor!=0 );
@@ -62128,6 +63953,7 @@
   if( pOp->opcode==OP_Insert ){
     u.bf.pKey = &aMem[pOp->p3];
     assert( u.bf.pKey->flags & MEM_Int );
+    assert( memIsValid(u.bf.pKey) );
     REGISTER_TRACE(pOp->p3, u.bf.pKey);
     u.bf.iKey = u.bf.pKey->u.i;
   }else{
@@ -62279,6 +64105,7 @@
 #endif /* local variables moved into u.bh */
 
   pOut = &aMem[pOp->p2];
+  memAboutToChange(p, pOut);
 
   /* Note that RowKey and RowData are really exactly the same instruction */
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
@@ -62363,9 +64190,7 @@
     u.bi.pModule = u.bi.pVtab->pModule;
     assert( u.bi.pModule->xRowid );
     rc = u.bi.pModule->xRowid(u.bi.pC->pVtabCursor, &u.bi.v);
-    sqlite3DbFree(db, p->zErrMsg);
-    p->zErrMsg = u.bi.pVtab->zErrMsg;
-    u.bi.pVtab->zErrMsg = 0;
+    importVtabErrMsg(p, u.bi.pVtab);
 #endif /* SQLITE_OMIT_VIRTUALTABLE */
   }else{
     assert( u.bi.pC->pCursor!=0 );
@@ -62623,6 +64448,9 @@
     u.bo.r.nField = (u16)pOp->p3;
     u.bo.r.flags = 0;
     u.bo.r.aMem = &aMem[pOp->p2];
+#ifdef SQLITE_DEBUG
+    { int i; for(i=0; i<u.bo.r.nField; i++) assert( memIsValid(&u.bo.r.aMem[i]) ); }
+#endif
     rc = sqlite3BtreeMovetoUnpacked(u.bo.pCrsr, &u.bo.r, 0, 0, &u.bo.res);
     if( rc==SQLITE_OK && u.bo.res==0 ){
       rc = sqlite3BtreeDelete(u.bo.pCrsr);
@@ -62684,7 +64512,7 @@
 ** that if the key from register P3 is a prefix of the key in the cursor,
 ** the result is false whereas it would be true with IdxGT.
 */
-/* Opcode: IdxLT P1 P2 P3 * P5
+/* Opcode: IdxLT P1 P2 P3 P4 P5
 **
 ** The P4 register values beginning with P3 form an unpacked index 
 ** key that omits the ROWID.  Compare this key value against the index 
@@ -62707,6 +64535,7 @@
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
   u.bq.pC = p->apCsr[pOp->p1];
   assert( u.bq.pC!=0 );
+  assert( u.bq.pC->isOrdered );
   if( ALWAYS(u.bq.pC->pCursor!=0) ){
     assert( u.bq.pC->deferredMoveto==0 );
     assert( pOp->p5==0 || pOp->p5==1 );
@@ -62719,6 +64548,9 @@
       u.bq.r.flags = UNPACKED_IGNORE_ROWID;
     }
     u.bq.r.aMem = &aMem[pOp->p3];
+#ifdef SQLITE_DEBUG
+    { int i; for(i=0; i<u.bq.r.nField; i++) assert( memIsValid(&u.bq.r.aMem[i]) ); }
+#endif
     rc = sqlite3VdbeIdxKeyCompare(u.bq.pC, &u.bq.r, &u.bq.res);
     if( pOp->opcode==OP_IdxLT ){
       u.bq.res = -u.bq.res;
@@ -62822,6 +64654,8 @@
   if( pOp->p3 ){
     p->nChange += u.bs.nChange;
     if( pOp->p3>0 ){
+      assert( memIsValid(&aMem[pOp->p3]) );
+      memAboutToChange(p, &aMem[pOp->p3]);
       aMem[pOp->p3].u.i += u.bs.nChange;
     }
   }
@@ -62865,9 +64699,9 @@
   assert( u.bt.pDb->pBt!=0 );
   if( pOp->opcode==OP_CreateTable ){
     /* u.bt.flags = BTREE_INTKEY; */
-    u.bt.flags = BTREE_LEAFDATA|BTREE_INTKEY;
+    u.bt.flags = BTREE_INTKEY;
   }else{
-    u.bt.flags = BTREE_ZERODATA;
+    u.bt.flags = BTREE_BLOBKEY;
   }
   rc = sqlite3BtreeCreateTable(u.bt.pDb->pBt, &u.bt.pgno, u.bt.flags);
   pOut->u.i = u.bt.pgno;
@@ -63196,6 +65030,7 @@
 
   u.by.pProgram = pOp->p4.pProgram;
   u.by.pRt = &aMem[pOp->p3];
+  assert( memIsValid(u.by.pRt) );
   assert( u.by.pProgram->nOp>0 );
 
   /* If the p5 flag is clear, then recursive invocation of triggers is
@@ -63369,6 +65204,7 @@
   }else{
     u.ca.pIn1 = &aMem[pOp->p1];
   }
+  assert( memIsValid(u.ca.pIn1) );
   sqlite3VdbeMemIntegerify(u.ca.pIn1);
   pIn2 = &aMem[pOp->p2];
   sqlite3VdbeMemIntegerify(pIn2);
@@ -63455,7 +65291,9 @@
   u.cb.apVal = p->apArg;
   assert( u.cb.apVal || u.cb.n==0 );
   for(u.cb.i=0; u.cb.i<u.cb.n; u.cb.i++, u.cb.pRec++){
+    assert( memIsValid(u.cb.pRec) );
     u.cb.apVal[u.cb.i] = u.cb.pRec;
+    memAboutToChange(p, u.cb.pRec);
     sqlite3VdbeMemStoreType(u.cb.pRec);
   }
   u.cb.ctx.pFunc = pOp->p4.pFunc;
@@ -63475,7 +65313,7 @@
     assert( pOp[-1].opcode==OP_CollSeq );
     u.cb.ctx.pColl = pOp[-1].p4.pColl;
   }
-  (u.cb.ctx.pFunc->xStep)(&u.cb.ctx, u.cb.n, u.cb.apVal);
+  (u.cb.ctx.pFunc->xStep)(&u.cb.ctx, u.cb.n, u.cb.apVal); /* IMP: R-24505-23230 */
   if( u.cb.ctx.isError ){
     sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3_value_text(&u.cb.ctx.s));
     rc = u.cb.ctx.isError;
@@ -63538,11 +65376,6 @@
 ** If changing into or out of WAL mode the procedure is more complicated.
 **
 ** Write a string containing the final journal-mode to register P2.
-**
-** If an attempt to change in to or out of WAL mode fails because another
-** connection also has the same database open, then an SQLITE_BUSY error
-** is raised if P5==0, or of P5!=0 the journal mode changed is skipped
-** without signaling the error.
 */
 case OP_JournalMode: {    /* out2-prerelease */
 #if 0  /* local variables moved into u.cd */
@@ -63593,11 +65426,11 @@
   u.cd.zFilename = sqlite3PagerFilename(u.cd.pPager);
 
   /* Do not allow a transition to journal_mode=WAL for a database
-  ** in temporary storage or if the VFS does not support xShmOpen.
+  ** in temporary storage or if the VFS does not support shared memory
   */
   if( u.cd.eNew==PAGER_JOURNALMODE_WAL
    && (u.cd.zFilename[0]==0                         /* Temp file */
-       || !sqlite3PagerWalSupported(u.cd.pPager))   /* No xShmOpen support */
+       || !sqlite3PagerWalSupported(u.cd.pPager))   /* No shared-memory support */
   ){
     u.cd.eNew = u.cd.eOld;
   }
@@ -63642,7 +65475,6 @@
 #endif /* ifndef SQLITE_OMIT_WAL */
 
   if( rc ){
-    if( rc==SQLITE_BUSY && pOp->p5!=0 ) rc = SQLITE_OK;
     u.cd.eNew = u.cd.eOld;
   }
   u.cd.eNew = sqlite3PagerSetJournalMode(u.cd.pPager, u.cd.eNew);
@@ -63760,11 +65592,7 @@
 #endif /* local variables moved into u.cf */
   u.cf.pVTab = pOp->p4.pVtab;
   rc = sqlite3VtabBegin(db, u.cf.pVTab);
-  if( u.cf.pVTab ){
-    sqlite3DbFree(db, p->zErrMsg);
-    p->zErrMsg = u.cf.pVTab->pVtab->zErrMsg;
-    u.cf.pVTab->pVtab->zErrMsg = 0;
-  }
+  if( u.cf.pVTab ) importVtabErrMsg(p, u.cf.pVTab->pVtab);
   break;
 }
 #endif /* SQLITE_OMIT_VIRTUALTABLE */
@@ -63816,9 +65644,7 @@
   u.cg.pModule = (sqlite3_module *)u.cg.pVtab->pModule;
   assert(u.cg.pVtab && u.cg.pModule);
   rc = u.cg.pModule->xOpen(u.cg.pVtab, &u.cg.pVtabCursor);
-  sqlite3DbFree(db, p->zErrMsg);
-  p->zErrMsg = u.cg.pVtab->zErrMsg;
-  u.cg.pVtab->zErrMsg = 0;
+  importVtabErrMsg(p, u.cg.pVtab);
   if( SQLITE_OK==rc ){
     /* Initialize sqlite3_vtab_cursor base class */
     u.cg.pVtabCursor->pVtab = u.cg.pVtab;
@@ -63874,6 +65700,7 @@
   u.ch.pQuery = &aMem[pOp->p3];
   u.ch.pArgc = &u.ch.pQuery[1];
   u.ch.pCur = p->apCsr[pOp->p1];
+  assert( memIsValid(u.ch.pQuery) );
   REGISTER_TRACE(pOp->p3, u.ch.pQuery);
   assert( u.ch.pCur->pVtabCursor );
   u.ch.pVtabCursor = u.ch.pCur->pVtabCursor;
@@ -63897,9 +65724,7 @@
     p->inVtabMethod = 1;
     rc = u.ch.pModule->xFilter(u.ch.pVtabCursor, u.ch.iQuery, pOp->p4.z, u.ch.nArg, u.ch.apArg);
     p->inVtabMethod = 0;
-    sqlite3DbFree(db, p->zErrMsg);
-    p->zErrMsg = u.ch.pVtab->zErrMsg;
-    u.ch.pVtab->zErrMsg = 0;
+    importVtabErrMsg(p, u.ch.pVtab);
     if( rc==SQLITE_OK ){
       u.ch.res = u.ch.pModule->xEof(u.ch.pVtabCursor);
     }
@@ -63933,6 +65758,7 @@
   assert( pCur->pVtabCursor );
   assert( pOp->p3>0 && pOp->p3<=p->nMem );
   u.ci.pDest = &aMem[pOp->p3];
+  memAboutToChange(p, u.ci.pDest);
   if( pCur->nullRow ){
     sqlite3VdbeMemSetNull(u.ci.pDest);
     break;
@@ -63951,9 +65777,7 @@
   MemSetTypeFlag(&u.ci.sContext.s, MEM_Null);
 
   rc = u.ci.pModule->xColumn(pCur->pVtabCursor, &u.ci.sContext, pOp->p2);
-  sqlite3DbFree(db, p->zErrMsg);
-  p->zErrMsg = u.ci.pVtab->zErrMsg;
-  u.ci.pVtab->zErrMsg = 0;
+  importVtabErrMsg(p, u.ci.pVtab);
   if( u.ci.sContext.isError ){
     rc = u.ci.sContext.isError;
   }
@@ -64008,9 +65832,7 @@
   p->inVtabMethod = 1;
   rc = u.cj.pModule->xNext(u.cj.pCur->pVtabCursor);
   p->inVtabMethod = 0;
-  sqlite3DbFree(db, p->zErrMsg);
-  p->zErrMsg = u.cj.pVtab->zErrMsg;
-  u.cj.pVtab->zErrMsg = 0;
+  importVtabErrMsg(p, u.cj.pVtab);
   if( rc==SQLITE_OK ){
     u.cj.res = u.cj.pModule->xEof(u.cj.pCur->pVtabCursor);
   }
@@ -64039,12 +65861,12 @@
   u.ck.pVtab = pOp->p4.pVtab->pVtab;
   u.ck.pName = &aMem[pOp->p1];
   assert( u.ck.pVtab->pModule->xRename );
+  assert( memIsValid(u.ck.pName) );
   REGISTER_TRACE(pOp->p1, u.ck.pName);
   assert( u.ck.pName->flags & MEM_Str );
   rc = u.ck.pVtab->pModule->xRename(u.ck.pVtab, u.ck.pName->z);
-  sqlite3DbFree(db, p->zErrMsg);
-  p->zErrMsg = u.ck.pVtab->zErrMsg;
-  u.ck.pVtab->zErrMsg = 0;
+  importVtabErrMsg(p, u.ck.pVtab);
+  p->expired = 0;
 
   break;
 }
@@ -64093,14 +65915,14 @@
     u.cl.apArg = p->apArg;
     u.cl.pX = &aMem[pOp->p3];
     for(u.cl.i=0; u.cl.i<u.cl.nArg; u.cl.i++){
+      assert( memIsValid(u.cl.pX) );
+      memAboutToChange(p, u.cl.pX);
       sqlite3VdbeMemStoreType(u.cl.pX);
       u.cl.apArg[u.cl.i] = u.cl.pX;
       u.cl.pX++;
     }
     rc = u.cl.pModule->xUpdate(u.cl.pVtab, u.cl.nArg, u.cl.apArg, &u.cl.rowid);
-    sqlite3DbFree(db, p->zErrMsg);
-    p->zErrMsg = u.cl.pVtab->zErrMsg;
-    u.cl.pVtab->zErrMsg = 0;
+    importVtabErrMsg(p, u.cl.pVtab);
     if( rc==SQLITE_OK && pOp->p1 ){
       assert( u.cl.nArg>1 && u.cl.apArg[0] && (u.cl.apArg[0]->flags&MEM_Null) );
       db->lastRowid = u.cl.rowid;
@@ -64840,11 +66662,10 @@
   0,             /* xFileControl */
   0,             /* xSectorSize */
   0,             /* xDeviceCharacteristics */
-  0,             /* xShmOpen */
-  0,             /* xShmLock */
   0,             /* xShmMap */
+  0,             /* xShmLock */
   0,             /* xShmBarrier */
-  0              /* xShmClose */
+  0              /* xShmUnmap */
 };
 
 /* 
@@ -65125,11 +66946,10 @@
   0,                /* xFileControl */
   0,                /* xSectorSize */
   0,                /* xDeviceCharacteristics */
-  0,                /* xShmOpen */
-  0,                /* xShmLock */
   0,                /* xShmMap */
+  0,                /* xShmLock */
   0,                /* xShmBarrier */
-  0                 /* xShmClose */
+  0                 /* xShmUnlock */
 };
 
 /* 
@@ -65151,8 +66971,7 @@
 }
 
 /* 
-** Return the number of bytes required to store a MemJournal that uses vfs
-** pVfs to create the underlying on-disk files.
+** Return the number of bytes required to store a MemJournal file descriptor.
 */
 SQLITE_PRIVATE int sqlite3MemJournalSize(void){
   return sizeof(MemJournal);
@@ -66557,24 +68376,31 @@
 }
 
 /*
+** Set the explicit collating sequence for an expression to the
+** collating sequence supplied in the second argument.
+*/
+SQLITE_PRIVATE Expr *sqlite3ExprSetColl(Expr *pExpr, CollSeq *pColl){
+  if( pExpr && pColl ){
+    pExpr->pColl = pColl;
+    pExpr->flags |= EP_ExpCollate;
+  }
+  return pExpr;
+}
+
+/*
 ** Set the collating sequence for expression pExpr to be the collating
 ** sequence named by pToken.   Return a pointer to the revised expression.
 ** The collating sequence is marked as "explicit" using the EP_ExpCollate
 ** flag.  An explicit collating sequence will override implicit
 ** collating sequences.
 */
-SQLITE_PRIVATE Expr *sqlite3ExprSetColl(Parse *pParse, Expr *pExpr, Token *pCollName){
+SQLITE_PRIVATE Expr *sqlite3ExprSetCollByToken(Parse *pParse, Expr *pExpr, Token *pCollName){
   char *zColl = 0;            /* Dequoted name of collation sequence */
   CollSeq *pColl;
   sqlite3 *db = pParse->db;
   zColl = sqlite3NameFromToken(db, pCollName);
-  if( pExpr && zColl ){
-    pColl = sqlite3LocateCollSeq(pParse, zColl);
-    if( pColl ){
-      pExpr->pColl = pColl;
-      pExpr->flags |= EP_ExpCollate;
-    }
-  }
+  pColl = sqlite3LocateCollSeq(pParse, zColl);
+  sqlite3ExprSetColl(pExpr, pColl);
   sqlite3DbFree(db, zColl);
   return pExpr;
 }
@@ -67048,18 +68874,19 @@
   }else if( z[0]=='?' ){
     /* Wildcard of the form "?nnn".  Convert "nnn" to an integer and
     ** use it as the variable number */
-    int i = atoi((char*)&z[1]);
+    i64 i;
+    int bOk = sqlite3Atoi64(&z[1], &i);
     pExpr->iColumn = (ynVar)i;
     testcase( i==0 );
     testcase( i==1 );
     testcase( i==db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER]-1 );
     testcase( i==db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] );
-    if( i<1 || i>db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] ){
+    if( bOk==0 || i<1 || i>db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] ){
       sqlite3ErrorMsg(pParse, "variable number must be between ?1 and ?%d",
           db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER]);
     }
     if( i>pParse->nVar ){
-      pParse->nVar = i;
+      pParse->nVar = (int)i;
     }
   }else{
     /* Wildcards like ":aaa", "$aaa" or "@aaa".  Reuse the same variable
@@ -68006,14 +69833,20 @@
     /* Could not found an existing table or index to use as the RHS b-tree.
     ** We will have to generate an ephemeral table to do the job.
     */
+    double savedNQueryLoop = pParse->nQueryLoop;
     int rMayHaveNull = 0;
     eType = IN_INDEX_EPH;
     if( prNotFound ){
       *prNotFound = rMayHaveNull = ++pParse->nMem;
-    }else if( pX->pLeft->iColumn<0 && !ExprHasAnyProperty(pX, EP_xIsSelect) ){
-      eType = IN_INDEX_ROWID;
+    }else{
+      testcase( pParse->nQueryLoop>(double)1 );
+      pParse->nQueryLoop = (double)1;
+      if( pX->pLeft->iColumn<0 && !ExprHasAnyProperty(pX, EP_xIsSelect) ){
+        eType = IN_INDEX_ROWID;
+      }
     }
     sqlite3CodeSubselect(pParse, pX, rMayHaveNull, eType==IN_INDEX_ROWID);
+    pParse->nQueryLoop = savedNQueryLoop;
   }else{
     pX->iTable = iTab;
   }
@@ -68022,8 +69855,8 @@
 #endif
 
 /*
-** Generate code for scalar subqueries used as an expression
-** and IN operators.  Examples:
+** Generate code for scalar subqueries used as a subquery expression, EXISTS,
+** or IN operators.  Examples:
 **
 **     (SELECT a FROM b)          -- subquery
 **     EXISTS (SELECT a FROM b)   -- EXISTS subquery
@@ -68086,10 +69919,10 @@
 
   switch( pExpr->op ){
     case TK_IN: {
-      char affinity;
-      KeyInfo keyInfo;
-      int addr;        /* Address of OP_OpenEphemeral instruction */
-      Expr *pLeft = pExpr->pLeft;
+      char affinity;              /* Affinity of the LHS of the IN */
+      KeyInfo keyInfo;            /* Keyinfo for the generated table */
+      int addr;                   /* Address of OP_OpenEphemeral instruction */
+      Expr *pLeft = pExpr->pLeft; /* the LHS of the IN operator */
 
       if( rMayHaveNull ){
         sqlite3VdbeAddOp2(v, OP_Null, 0, rMayHaveNull);
@@ -68112,6 +69945,7 @@
       */
       pExpr->iTable = pParse->nTab++;
       addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pExpr->iTable, !isRowid);
+      if( rMayHaveNull==0 ) sqlite3VdbeChangeP5(v, BTREE_UNORDERED);
       memset(&keyInfo, 0, sizeof(keyInfo));
       keyInfo.nField = 1;
 
@@ -68136,7 +69970,7 @@
           keyInfo.aColl[0] = sqlite3BinaryCompareCollSeq(pParse, pExpr->pLeft,
               pEList->a[0].pExpr);
         }
-      }else if( pExpr->x.pList!=0 ){
+      }else if( ALWAYS(pExpr->x.pList!=0) ){
         /* Case 2:     expr IN (exprlist)
         **
         ** For each expression, build an index key from the evaluation and
@@ -68206,7 +70040,6 @@
       ** an integer 0 (not exists) or 1 (exists) into a memory cell
       ** and record that memory cell in iColumn.
       */
-      static const Token one = { "1", 1 };  /* Token for literal value 1 */
       Select *pSel;                         /* SELECT statement to encode */
       SelectDest dest;                      /* How to deal with SELECt result */
 
@@ -68227,7 +70060,8 @@
         VdbeComment((v, "Init EXISTS result"));
       }
       sqlite3ExprDelete(pParse->db, pSel->pLimit);
-      pSel->pLimit = sqlite3PExpr(pParse, TK_INTEGER, 0, 0, &one);
+      pSel->pLimit = sqlite3PExpr(pParse, TK_INTEGER, 0, 0,
+                                  &sqlite3IntTokens[1]);
       if( sqlite3Select(pParse, pSel, &dest) ){
         return 0;
       }
@@ -68295,8 +70129,20 @@
   sqlite3ExprCachePush(pParse);
   r1 = sqlite3GetTempReg(pParse);
   sqlite3ExprCode(pParse, pExpr->pLeft, r1);
-  sqlite3VdbeAddOp2(v, OP_IsNull, r1, destIfNull);
 
+  /* If the LHS is NULL, then the result is either false or NULL depending
+  ** on whether the RHS is empty or not, respectively.
+  */
+  if( destIfNull==destIfFalse ){
+    /* Shortcut for the common case where the false and NULL outcomes are
+    ** the same. */
+    sqlite3VdbeAddOp2(v, OP_IsNull, r1, destIfNull);
+  }else{
+    int addr1 = sqlite3VdbeAddOp1(v, OP_NotNull, r1);
+    sqlite3VdbeAddOp2(v, OP_Rewind, pExpr->iTable, destIfFalse);
+    sqlite3VdbeAddOp2(v, OP_Goto, 0, destIfNull);
+    sqlite3VdbeJumpHere(v, addr1);
+  }
 
   if( eType==IN_INDEX_ROWID ){
     /* In this case, the RHS is the ROWID of table b-tree
@@ -68709,73 +70555,6 @@
 #endif /* SQLITE_DEBUG || SQLITE_COVERAGE_TEST */
 
 /*
-** If the last instruction coded is an ephemeral copy of any of
-** the registers in the nReg registers beginning with iReg, then
-** convert the last instruction from OP_SCopy to OP_Copy.
-*/
-SQLITE_PRIVATE void sqlite3ExprHardCopy(Parse *pParse, int iReg, int nReg){
-  VdbeOp *pOp;
-  Vdbe *v;
-
-  assert( pParse->db->mallocFailed==0 );
-  v = pParse->pVdbe;
-  assert( v!=0 );
-  pOp = sqlite3VdbeGetOp(v, -1);
-  assert( pOp!=0 );
-  if( pOp->opcode==OP_SCopy && pOp->p1>=iReg && pOp->p1<iReg+nReg ){
-    pOp->opcode = OP_Copy;
-  }
-}
-
-/*
-** Generate code to store the value of the iAlias-th alias in register
-** target.  The first time this is called, pExpr is evaluated to compute
-** the value of the alias.  The value is stored in an auxiliary register
-** and the number of that register is returned.  On subsequent calls,
-** the register number is returned without generating any code.
-**
-** Note that in order for this to work, code must be generated in the
-** same order that it is executed.
-**
-** Aliases are numbered starting with 1.  So iAlias is in the range
-** of 1 to pParse->nAlias inclusive.  
-**
-** pParse->aAlias[iAlias-1] records the register number where the value
-** of the iAlias-th alias is stored.  If zero, that means that the
-** alias has not yet been computed.
-*/
-static int codeAlias(Parse *pParse, int iAlias, Expr *pExpr, int target){
-#if 0
-  sqlite3 *db = pParse->db;
-  int iReg;
-  if( pParse->nAliasAlloc<pParse->nAlias ){
-    pParse->aAlias = sqlite3DbReallocOrFree(db, pParse->aAlias,
-                                 sizeof(pParse->aAlias[0])*pParse->nAlias );
-    testcase( db->mallocFailed && pParse->nAliasAlloc>0 );
-    if( db->mallocFailed ) return 0;
-    memset(&pParse->aAlias[pParse->nAliasAlloc], 0,
-           (pParse->nAlias-pParse->nAliasAlloc)*sizeof(pParse->aAlias[0]));
-    pParse->nAliasAlloc = pParse->nAlias;
-  }
-  assert( iAlias>0 && iAlias<=pParse->nAlias );
-  iReg = pParse->aAlias[iAlias-1];
-  if( iReg==0 ){
-    if( pParse->iCacheLevel>0 ){
-      iReg = sqlite3ExprCodeTarget(pParse, pExpr, target);
-    }else{
-      iReg = ++pParse->nMem;
-      sqlite3ExprCode(pParse, pExpr, iReg);
-      pParse->aAlias[iAlias-1] = iReg;
-    }
-  }
-  return iReg;
-#else
-  UNUSED_PARAMETER(iAlias);
-  return sqlite3ExprCodeTarget(pParse, pExpr, target);
-#endif
-}
-
-/*
 ** Generate code into the current Vdbe to evaluate the given
 ** expression.  Attempt to store the results in register "target".
 ** Return the register where results are stored.
@@ -68883,7 +70662,7 @@
       break;
     }
     case TK_AS: {
-      inReg = codeAlias(pParse, pExpr->iTable, pExpr->pLeft, target);
+      inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
       break;
     }
 #ifndef SQLITE_OMIT_CAST
@@ -69315,6 +71094,11 @@
         opCompare.op = TK_EQ;
         opCompare.pLeft = &cacheX;
         pTest = &opCompare;
+        /* Ticket b351d95f9cd5ef17e9d9dbae18f5ca8611190001:
+        ** The value in regFree1 might get SCopy-ed into the file result.
+        ** So make sure that the regFree1 register is not reused for other
+        ** purposes and possibly overwritten.  */
+        regFree1 = 0;
       }
       for(i=0; i<nExpr; i=i+2){
         sqlite3ExprCachePush(pParse);
@@ -69408,10 +71192,14 @@
   int inReg;
 
   assert( target>0 && target<=pParse->nMem );
-  inReg = sqlite3ExprCodeTarget(pParse, pExpr, target);
-  assert( pParse->pVdbe || pParse->db->mallocFailed );
-  if( inReg!=target && pParse->pVdbe ){
-    sqlite3VdbeAddOp2(pParse->pVdbe, OP_SCopy, inReg, target);
+  if( pExpr && pExpr->op==TK_REGISTER ){
+    sqlite3VdbeAddOp2(pParse->pVdbe, OP_Copy, pExpr->iTable, target);
+  }else{
+    inReg = sqlite3ExprCodeTarget(pParse, pExpr, target);
+    assert( pParse->pVdbe || pParse->db->mallocFailed );
+    if( inReg!=target && pParse->pVdbe ){
+      sqlite3VdbeAddOp2(pParse->pVdbe, OP_SCopy, inReg, target);
+    }
   }
   return target;
 }
@@ -69584,19 +71372,14 @@
   int i, n;
   assert( pList!=0 );
   assert( target>0 );
+  assert( pParse->pVdbe!=0 );  /* Never gets this far otherwise */
   n = pList->nExpr;
   for(pItem=pList->a, i=0; i<n; i++, pItem++){
-    if( pItem->iAlias ){
-      int iReg = codeAlias(pParse, pItem->iAlias, pItem->pExpr, target+i);
-      Vdbe *v = sqlite3GetVdbe(pParse);
-      if( iReg!=target+i ){
-        sqlite3VdbeAddOp2(v, OP_SCopy, iReg, target+i);
-      }
-    }else{
-      sqlite3ExprCode(pParse, pItem->pExpr, target+i);
-    }
-    if( doHardCopy && !pParse->db->mallocFailed ){
-      sqlite3ExprHardCopy(pParse, target, n);
+    Expr *pExpr = pItem->pExpr;
+    int inReg = sqlite3ExprCodeTarget(pParse, pExpr, target+i);
+    if( inReg!=target+i ){
+      sqlite3VdbeAddOp2(pParse->pVdbe, doHardCopy ? OP_Copy : OP_SCopy,
+                        inReg, target+i);
     }
   }
   return n;
@@ -71034,7 +72817,6 @@
   if( !pNew ) goto exit_begin_add_column;
   pParse->pNewTable = pNew;
   pNew->nRef = 1;
-  pNew->dbMem = pTab->dbMem;
   pNew->nCol = pTab->nCol;
   assert( pNew->nCol>0 );
   nAlloc = (((pNew->nCol-1)/8)*8)+8;
@@ -71187,6 +72969,7 @@
   int topOfLoop;               /* The top of the loop */
   int endOfLoop;               /* The end of the loop */
   int addr;                    /* The address of an instruction */
+  int jZeroRows = 0;           /* Jump from here if number of rows is zero */
   int iDb;                     /* Index of database containing pTab */
   int regTabname = iMem++;     /* Register containing table name */
   int regIdxname = iMem++;     /* Register containing index name */
@@ -71205,8 +72988,15 @@
 #endif
 
   v = sqlite3GetVdbe(pParse);
-  if( v==0 || NEVER(pTab==0) || pTab->pIndex==0 ){
-    /* Do no analysis for tables that have no indices */
+  if( v==0 || NEVER(pTab==0) ){
+    return;
+  }
+  if( pTab->pSelect ){
+    /* Do not gather statistics on views */
+    return;
+  }
+  if( memcmp(pTab->zName, "sqlite_", 7)==0 ){
+    /* Do not gather statistics on system tables */
     return;
   }
   assert( sqlite3BtreeHoldsAllMutexes(db) );
@@ -71223,6 +73013,7 @@
   sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);
 
   iIdxCur = pParse->nTab++;
+  sqlite3VdbeAddOp4(v, OP_String8, 0, regTabname, 0, pTab->zName, 0);
   for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
     int nCol = pIdx->nColumn;
     KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx);
@@ -71237,10 +73028,7 @@
         (char *)pKey, P4_KEYINFO_HANDOFF);
     VdbeComment((v, "%s", pIdx->zName));
 
-    /* Populate the registers containing the table and index names. */
-    if( pTab->pIndex==pIdx ){
-      sqlite3VdbeAddOp4(v, OP_String8, 0, regTabname, 0, pTab->zName, 0);
-    }
+    /* Populate the register containing the index name. */
     sqlite3VdbeAddOp4(v, OP_String8, 0, regIdxname, 0, pIdx->zName, 0);
 
 #ifdef SQLITE_ENABLE_STAT2
@@ -71375,8 +73163,10 @@
     ** If K>0 then it is always the case the D>0 so division by zero
     ** is never possible.
     */
-    addr = sqlite3VdbeAddOp1(v, OP_IfNot, iMem);
     sqlite3VdbeAddOp2(v, OP_SCopy, iMem, regSampleno);
+    if( jZeroRows==0 ){
+      jZeroRows = sqlite3VdbeAddOp1(v, OP_IfNot, iMem);
+    }
     for(i=0; i<nCol; i++){
       sqlite3VdbeAddOp4(v, OP_String8, 0, regTemp, 0, " ", 0);
       sqlite3VdbeAddOp3(v, OP_Concat, regTemp, regSampleno, regSampleno);
@@ -71390,13 +73180,35 @@
     sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur, regRowid);
     sqlite3VdbeAddOp3(v, OP_Insert, iStatCur, regRec, regRowid);
     sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
+  }
+
+  /* If the table has no indices, create a single sqlite_stat1 entry
+  ** containing NULL as the index name and the row count as the content.
+  */
+  if( pTab->pIndex==0 ){
+    sqlite3VdbeAddOp3(v, OP_OpenRead, iIdxCur, pTab->tnum, iDb);
+    VdbeComment((v, "%s", pTab->zName));
+    sqlite3VdbeAddOp2(v, OP_Count, iIdxCur, regSampleno);
+    sqlite3VdbeAddOp1(v, OP_Close, iIdxCur);
+  }else{
+    assert( jZeroRows>0 );
+    addr = sqlite3VdbeAddOp0(v, OP_Goto);
+    sqlite3VdbeJumpHere(v, jZeroRows);
+  }
+  sqlite3VdbeAddOp2(v, OP_Null, 0, regIdxname);
+  sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 3, regRec, "aaa", 0);
+  sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur, regRowid);
+  sqlite3VdbeAddOp3(v, OP_Insert, iStatCur, regRec, regRowid);
+  sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
+  if( pParse->nMem<regRec ) pParse->nMem = regRec;
+  if( jZeroRows ){
     sqlite3VdbeJumpHere(v, addr);
   }
 }
 
 /*
 ** Generate code that will cause the most recent index analysis to
-** be laoded into internal hash tables where is can be used.
+** be loaded into internal hash tables where is can be used.
 */
 static void loadAnalysis(Parse *pParse, int iDb){
   Vdbe *v = sqlite3GetVdbe(pParse);
@@ -71526,33 +73338,46 @@
 ** This callback is invoked once for each index when reading the
 ** sqlite_stat1 table.  
 **
-**     argv[0] = name of the index
-**     argv[1] = results of analysis - on integer for each column
+**     argv[0] = name of the table
+**     argv[1] = name of the index (might be NULL)
+**     argv[2] = results of analysis - on integer for each column
+**
+** Entries for which argv[1]==NULL simply record the number of rows in
+** the table.
 */
 static int analysisLoader(void *pData, int argc, char **argv, char **NotUsed){
   analysisInfo *pInfo = (analysisInfo*)pData;
   Index *pIndex;
-  int i, c;
+  Table *pTable;
+  int i, c, n;
   unsigned int v;
   const char *z;
 
-  assert( argc==2 );
+  assert( argc==3 );
   UNUSED_PARAMETER2(NotUsed, argc);
 
-  if( argv==0 || argv[0]==0 || argv[1]==0 ){
+  if( argv==0 || argv[0]==0 || argv[2]==0 ){
     return 0;
   }
-  pIndex = sqlite3FindIndex(pInfo->db, argv[0], pInfo->zDatabase);
-  if( pIndex==0 ){
+  pTable = sqlite3FindTable(pInfo->db, argv[0], pInfo->zDatabase);
+  if( pTable==0 ){
     return 0;
   }
-  z = argv[1];
-  for(i=0; *z && i<=pIndex->nColumn; i++){
+  if( argv[1] ){
+    pIndex = sqlite3FindIndex(pInfo->db, argv[1], pInfo->zDatabase);
+  }else{
+    pIndex = 0;
+  }
+  n = pIndex ? pIndex->nColumn : 0;
+  z = argv[2];
+  for(i=0; *z && i<=n; i++){
     v = 0;
     while( (c=z[0])>='0' && c<='9' ){
       v = v*10 + c - '0';
       z++;
     }
+    if( i==0 ) pTable->nRowEst = v;
+    if( pIndex==0 ) break;
     pIndex->aiRowEst[i] = v;
     if( *z==' ' ) z++;
   }
@@ -71563,21 +73388,20 @@
 ** If the Index.aSample variable is not NULL, delete the aSample[] array
 ** and its contents.
 */
-SQLITE_PRIVATE void sqlite3DeleteIndexSamples(Index *pIdx){
+SQLITE_PRIVATE void sqlite3DeleteIndexSamples(sqlite3 *db, Index *pIdx){
 #ifdef SQLITE_ENABLE_STAT2
   if( pIdx->aSample ){
     int j;
-    sqlite3 *dbMem = pIdx->pTable->dbMem;
     for(j=0; j<SQLITE_INDEX_SAMPLES; j++){
       IndexSample *p = &pIdx->aSample[j];
       if( p->eType==SQLITE_TEXT || p->eType==SQLITE_BLOB ){
-        sqlite3DbFree(pIdx->pTable->dbMem, p->u.z);
+        sqlite3DbFree(db, p->u.z);
       }
     }
-    sqlite3DbFree(dbMem, pIdx->aSample);
-    pIdx->aSample = 0;
+    sqlite3DbFree(db, pIdx->aSample);
   }
 #else
+  UNUSED_PARAMETER(db);
   UNUSED_PARAMETER(pIdx);
 #endif
 }
@@ -71616,7 +73440,8 @@
   for(i=sqliteHashFirst(&db->aDb[iDb].pSchema->idxHash);i;i=sqliteHashNext(i)){
     Index *pIdx = sqliteHashData(i);
     sqlite3DefaultRowEst(pIdx);
-    sqlite3DeleteIndexSamples(pIdx);
+    sqlite3DeleteIndexSamples(db, pIdx);
+    pIdx->aSample = 0;
   }
 
   /* Check to make sure the sqlite_stat1 table exists */
@@ -71628,7 +73453,7 @@
 
   /* Load new statistics out of the sqlite_stat1 table */
   zSql = sqlite3MPrintf(db, 
-      "SELECT idx, stat FROM %Q.sqlite_stat1", sInfo.zDatabase);
+      "SELECT tbl, idx, stat FROM %Q.sqlite_stat1", sInfo.zDatabase);
   if( zSql==0 ){
     rc = SQLITE_NOMEM;
   }else{
@@ -71660,18 +73485,17 @@
         Index *pIdx = sqlite3FindIndex(db, zIndex, sInfo.zDatabase);
         if( pIdx ){
           int iSample = sqlite3_column_int(pStmt, 1);
-          sqlite3 *dbMem = pIdx->pTable->dbMem;
-          assert( dbMem==db || dbMem==0 );
           if( iSample<SQLITE_INDEX_SAMPLES && iSample>=0 ){
             int eType = sqlite3_column_type(pStmt, 2);
 
             if( pIdx->aSample==0 ){
               static const int sz = sizeof(IndexSample)*SQLITE_INDEX_SAMPLES;
-              pIdx->aSample = (IndexSample *)sqlite3DbMallocZero(dbMem, sz);
+              pIdx->aSample = (IndexSample *)sqlite3DbMallocRaw(0, sz);
               if( pIdx->aSample==0 ){
                 db->mallocFailed = 1;
                 break;
               }
+	      memset(pIdx->aSample, 0, sz);
             }
 
             assert( pIdx->aSample );
@@ -71694,10 +73518,8 @@
                 if( n < 1){
                   pSample->u.z = 0;
                 }else{
-                  pSample->u.z = sqlite3DbMallocRaw(dbMem, n);
-                  if( pSample->u.z ){
-                    memcpy(pSample->u.z, z, n);
-                  }else{
+                  pSample->u.z = sqlite3DbStrNDup(0, z, n);
+                  if( pSample->u.z==0 ){
                     db->mallocFailed = 1;
                     break;
                   }
@@ -71848,9 +73670,8 @@
   ** it to obtain the database schema. At this point the schema may
   ** or may not be initialised.
   */
-  rc = sqlite3BtreeFactory(db, zFile, 0, SQLITE_DEFAULT_CACHE_SIZE,
-                           db->openFlags | SQLITE_OPEN_MAIN_DB,
-                           &aNew->pBt);
+  rc = sqlite3BtreeOpen(zFile, db, &aNew->pBt, 0,
+                        db->openFlags | SQLITE_OPEN_MAIN_DB);
   db->nDb++;
   if( rc==SQLITE_CONSTRAINT ){
     rc = SQLITE_ERROR;
@@ -71867,8 +73688,6 @@
     }
     pPager = sqlite3BtreePager(aNew->pBt);
     sqlite3PagerLockingMode(pPager, db->dfltLockMode);
-    /* journal_mode set by the OP_JournalMode opcode that will following
-    ** the OP_Function opcode that invoked this function. */
     sqlite3BtreeSecureDelete(aNew->pBt,
                              sqlite3BtreeSecureDelete(db->aDb[0].pBt,-1) );
   }
@@ -72064,17 +73883,6 @@
     sqlite3VdbeChangeP5(v, (u8)(pFunc->nArg));
     sqlite3VdbeChangeP4(v, -1, (char *)pFunc, P4_FUNCDEF);
 
-    if( type==SQLITE_ATTACH ){
-      /* On an attach, also set the journal mode.  Note that
-      ** sqlite3VdbeUsesBtree() is not call here since the iDb index
-      ** will be out of range prior to the new database being attached.
-      ** The OP_JournalMode opcode will all sqlite3VdbeUsesBtree() for us.
-      */
-      sqlite3VdbeAddOp3(v, OP_JournalMode, db->nDb, regArgs+3, 
-                           db->dfltJournalMode);
-      sqlite3VdbeChangeP5(v, 1);
-    }
-
     /* Code an OP_Expire. For an ATTACH statement, set P1 to true (expire this
     ** statement only). For DETACH, set it to false (expire all existing
     ** statements).
@@ -72873,34 +74681,15 @@
 /*
 ** Reclaim the memory used by an index
 */
-static void freeIndex(Index *p){
-  sqlite3 *db = p->pTable->dbMem;
+static void freeIndex(sqlite3 *db, Index *p){
 #ifndef SQLITE_OMIT_ANALYZE
-  sqlite3DeleteIndexSamples(p);
+  sqlite3DeleteIndexSamples(db, p);
 #endif
   sqlite3DbFree(db, p->zColAff);
   sqlite3DbFree(db, p);
 }
 
 /*
-** Remove the given index from the index hash table, and free
-** its memory structures.
-**
-** The index is removed from the database hash tables but
-** it is not unlinked from the Table that it indexes.
-** Unlinking from the Table must be done by the calling function.
-*/
-static void sqlite3DeleteIndex(Index *p){
-  Index *pOld;
-  const char *zName = p->zName;
-
-  pOld = sqlite3HashInsert(&p->pSchema->idxHash, zName,
-                           sqlite3Strlen30(zName), 0);
-  assert( pOld==0 || pOld==p );
-  freeIndex(p);
-}
-
-/*
 ** For the index called zIdxName which is found in the database iDb,
 ** unlike that index from its Table then remove the index from
 ** the index hash table and free all memory structures associated
@@ -72926,7 +74715,7 @@
         p->pNext = pIndex->pNext;
       }
     }
-    freeIndex(pIndex);
+    freeIndex(db, pIndex);
   }
   db->flags |= SQLITE_InternChanges;
 }
@@ -72997,13 +74786,12 @@
 }
 
 /*
-** Clear the column names from a table or view.
+** Delete memory allocated for the column names of a table or view (the
+** Table.aCol[] array).
 */
-static void sqliteResetColumnNames(Table *pTable){
+static void sqliteDeleteColumnNames(sqlite3 *db, Table *pTable){
   int i;
   Column *pCol;
-  sqlite3 *db = pTable->dbMem;
-  testcase( db==0 );
   assert( pTable!=0 );
   if( (pCol = pTable->aCol)!=0 ){
     for(i=0; i<pTable->nCol; i++, pCol++){
@@ -73015,8 +74803,6 @@
     }
     sqlite3DbFree(db, pTable->aCol);
   }
-  pTable->aCol = 0;
-  pTable->nCol = 0;
 }
 
 /*
@@ -73028,42 +74814,44 @@
 ** memory structures of the indices and foreign keys associated with 
 ** the table.
 */
-SQLITE_PRIVATE void sqlite3DeleteTable(Table *pTable){
+SQLITE_PRIVATE void sqlite3DeleteTable(sqlite3 *db, Table *pTable){
   Index *pIndex, *pNext;
-  sqlite3 *db;
 
-  if( pTable==0 ) return;
-  db = pTable->dbMem;
-  testcase( db==0 );
+  assert( !pTable || pTable->nRef>0 );
 
   /* Do not delete the table until the reference count reaches zero. */
-  pTable->nRef--;
-  if( pTable->nRef>0 ){
-    return;
-  }
-  assert( pTable->nRef==0 );
+  if( !pTable ) return;
+  if( ((!db || db->pnBytesFreed==0) && (--pTable->nRef)>0) ) return;
 
-  /* Delete all indices associated with this table
-  */
+  /* Delete all indices associated with this table. */
   for(pIndex = pTable->pIndex; pIndex; pIndex=pNext){
     pNext = pIndex->pNext;
     assert( pIndex->pSchema==pTable->pSchema );
-    sqlite3DeleteIndex(pIndex);
+    if( !db || db->pnBytesFreed==0 ){
+      char *zName = pIndex->zName; 
+      TESTONLY ( Index *pOld = ) sqlite3HashInsert(
+	  &pIndex->pSchema->idxHash, zName, sqlite3Strlen30(zName), 0
+      );
+      assert( pOld==pIndex || pOld==0 );
+    }
+    freeIndex(db, pIndex);
   }
 
   /* Delete any foreign keys attached to this table. */
-  sqlite3FkDelete(pTable);
+  sqlite3FkDelete(db, pTable);
 
   /* Delete the Table structure itself.
   */
-  sqliteResetColumnNames(pTable);
+  sqliteDeleteColumnNames(db, pTable);
   sqlite3DbFree(db, pTable->zName);
   sqlite3DbFree(db, pTable->zColAff);
   sqlite3SelectDelete(db, pTable->pSelect);
 #ifndef SQLITE_OMIT_CHECK
   sqlite3ExprDelete(db, pTable->pCheck);
 #endif
-  sqlite3VtabClear(pTable);
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+  sqlite3VtabClear(db, pTable);
+#endif
   sqlite3DbFree(db, pTable);
 }
 
@@ -73082,7 +74870,7 @@
   pDb = &db->aDb[iDb];
   p = sqlite3HashInsert(&pDb->pSchema->tblHash, zTabName,
                         sqlite3Strlen30(zTabName),0);
-  sqlite3DeleteTable(p);
+  sqlite3DeleteTable(db, p);
   db->flags |= SQLITE_InternChanges;
 }
 
@@ -73350,7 +75138,7 @@
   pTable->iPKey = -1;
   pTable->pSchema = db->aDb[iDb].pSchema;
   pTable->nRef = 1;
-  pTable->dbMem = 0;
+  pTable->nRowEst = 1000000;
   assert( pParse->pNewTable==0 );
   pParse->pNewTable = pTable;
 
@@ -73902,7 +75690,7 @@
     zEnd = "\n)";
   }
   n += 35 + 6*p->nCol;
-  zStmt = sqlite3Malloc( n );
+  zStmt = sqlite3DbMallocRaw(0, n);
   if( zStmt==0 ){
     db->mallocFailed = 1;
     return 0;
@@ -74083,7 +75871,7 @@
         p->aCol = pSelTab->aCol;
         pSelTab->nCol = 0;
         pSelTab->aCol = 0;
-        sqlite3DeleteTable(pSelTab);
+        sqlite3DeleteTable(db, pSelTab);
       }
     }
 
@@ -74197,12 +75985,10 @@
   }
   sqlite3StartTable(pParse, pName1, pName2, isTemp, 1, 0, noErr);
   p = pParse->pNewTable;
-  if( p==0 ){
+  if( p==0 || pParse->nErr ){
     sqlite3SelectDelete(db, pSelect);
     return;
   }
-  assert( pParse->nErr==0 ); /* If sqlite3StartTable return non-NULL then
-                             ** there could not have been an error */
   sqlite3TwoPartName(pParse, pName1, pName2, &pName);
   iDb = sqlite3SchemaToIndex(db, p->pSchema);
   if( sqlite3FixInit(&sFix, pParse, iDb, "view", pName)
@@ -74327,7 +76113,7 @@
       pTable->aCol = pSelTab->aCol;
       pSelTab->nCol = 0;
       pSelTab->aCol = 0;
-      sqlite3DeleteTable(pSelTab);
+      sqlite3DeleteTable(db, pSelTab);
       pTable->pSchema->flags |= DB_UnresetViews;
     }else{
       pTable->nCol = 0;
@@ -74352,7 +76138,9 @@
   for(i=sqliteHashFirst(&db->aDb[idx].pSchema->tblHash); i;i=sqliteHashNext(i)){
     Table *pTab = sqliteHashData(i);
     if( pTab->pSelect ){
-      sqliteResetColumnNames(pTab);
+      sqliteDeleteColumnNames(db, pTab);
+      pTab->aCol = 0;
+      pTab->nCol = 0;
     }
   }
   DbClearProperty(db, idx, DB_UnresetViews);
@@ -75349,7 +77137,7 @@
   /* Clean up before exiting */
 exit_create_index:
   if( pIndex ){
-    sqlite3_free(pIndex->zColAff);
+    sqlite3DbFree(db, pIndex->zColAff);
     sqlite3DbFree(db, pIndex);
   }
   sqlite3ExprListDelete(db, pList);
@@ -75379,14 +77167,14 @@
 SQLITE_PRIVATE void sqlite3DefaultRowEst(Index *pIdx){
   unsigned *a = pIdx->aiRowEst;
   int i;
+  unsigned n;
   assert( a!=0 );
-  a[0] = 1000000;
-  for(i=pIdx->nColumn; i>=5; i--){
-    a[i] = 5;
-  }
-  while( i>=1 ){
-    a[i] = 11 - i;
-    i--;
+  a[0] = pIdx->pTable->nRowEst;
+  if( a[0]<10 ) a[0] = 10;
+  n = 10;
+  for(i=1; i<=pIdx->nColumn; i++){
+    a[i] = n;
+    if( n>5 ) n--;
   }
   if( pIdx->onError!=OE_None ){
     a[pIdx->nColumn] = 1;
@@ -75728,7 +77516,7 @@
     sqlite3DbFree(db, pItem->zName);
     sqlite3DbFree(db, pItem->zAlias);
     sqlite3DbFree(db, pItem->zIndex);
-    sqlite3DeleteTable(pItem->pTab);
+    sqlite3DeleteTable(db, pItem->pTab);
     sqlite3SelectDelete(db, pItem->pSelect);
     sqlite3ExprDelete(db, pItem->pOn);
     sqlite3IdListDelete(db, pItem->pUsing);
@@ -75938,7 +77726,7 @@
           SQLITE_OPEN_DELETEONCLOSE |
           SQLITE_OPEN_TEMP_DB;
 
-    rc = sqlite3BtreeFactory(db, 0, 0, SQLITE_DEFAULT_CACHE_SIZE, flags, &pBt);
+    rc = sqlite3BtreeOpen(0, db, &pBt, 0, flags);
     if( rc!=SQLITE_OK ){
       sqlite3ErrorMsg(pParse, "unable to open a temporary database "
         "file for storing temporary tables");
@@ -75951,7 +77739,6 @@
       db->mallocFailed = 1;
       return 1;
     }
-    sqlite3PagerSetJournalMode(sqlite3BtreePager(pBt), db->dfltJournalMode);
   }
   return 0;
 }
@@ -76596,7 +78383,7 @@
   ** priority to built-in functions.
   **
   ** Except, if createFlag is true, that means that we are trying to
-  ** install a new function.  Whatever FuncDef structure is returned will
+  ** install a new function.  Whatever FuncDef structure is returned it will
   ** have fields overwritten with new information appropriate for the
   ** new function.  But the FuncDefs for built-in functions are read-only.
   ** So we must not search for built-ins when creating a new function.
@@ -76660,8 +78447,7 @@
   sqlite3HashInit(&pSchema->tblHash);
   for(pElem=sqliteHashFirst(&temp1); pElem; pElem=sqliteHashNext(pElem)){
     Table *pTab = sqliteHashData(pElem);
-    assert( pTab->dbMem==0 );
-    sqlite3DeleteTable(pTab);
+    sqlite3DeleteTable(0, pTab);
   }
   sqlite3HashClear(&temp1);
   sqlite3HashClear(&pSchema->fkeyHash);
@@ -76678,7 +78464,7 @@
   if( pBt ){
     p = (Schema *)sqlite3BtreeSchema(pBt, sizeof(Schema), sqlite3SchemaFree);
   }else{
-    p = (Schema *)sqlite3MallocZero(sizeof(Schema));
+    p = (Schema *)sqlite3DbMallocZero(0, sizeof(Schema));
   }
   if( !p ){
     db->mallocFailed = 1;
@@ -76719,7 +78505,7 @@
   Table *pTab;
   assert( pItem && pSrc->nSrc==1 );
   pTab = sqlite3LocateTable(pParse, 0, pItem->zName, pItem->zDatabase);
-  sqlite3DeleteTable(pItem->pTab);
+  sqlite3DeleteTable(pParse->db, pItem->pTab);
   pItem->pTab = pTab;
   if( pTab ){
     pTab->nRef++;
@@ -78116,8 +79902,10 @@
   const char *zOptName;
   assert( argc==1 );
   UNUSED_PARAMETER(argc);
-  /* IMP: R-xxxx This function is an SQL wrapper around the
-  ** sqlite3_compileoption_used() C interface. */
+  /* IMP: R-39564-36305 The sqlite_compileoption_used() SQL
+  ** function is a wrapper around the sqlite3_compileoption_used() C/C++
+  ** function.
+  */
   if( (zOptName = (const char*)sqlite3_value_text(argv[0]))!=0 ){
     sqlite3_result_int(context, sqlite3_compileoption_used(zOptName));
   }
@@ -78138,8 +79926,9 @@
   int n;
   assert( argc==1 );
   UNUSED_PARAMETER(argc);
-  /* IMP: R-xxxx This function is an SQL wrapper around the
-  ** sqlite3_compileoption_get() C interface. */
+  /* IMP: R-04922-24076 The sqlite_compileoption_get() SQL function
+  ** is a wrapper around the sqlite3_compileoption_get() C/C++ function.
+  */
   n = sqlite3_value_int(argv[0]);
   sqlite3_result_text(context, sqlite3_compileoption_get(n), -1, SQLITE_STATIC);
 }
@@ -78338,14 +80127,14 @@
       testcase( nOut-2==db->aLimit[SQLITE_LIMIT_LENGTH] );
       if( nOut-1>db->aLimit[SQLITE_LIMIT_LENGTH] ){
         sqlite3_result_error_toobig(context);
-        sqlite3DbFree(db, zOut);
+        sqlite3_free(zOut);
         return;
       }
       zOld = zOut;
       zOut = sqlite3_realloc(zOut, (int)nOut);
       if( zOut==0 ){
         sqlite3_result_error_nomem(context);
-        sqlite3DbFree(db, zOld);
+        sqlite3_free(zOld);
         return;
       }
       memcpy(&zOut[j], zRep, nRep);
@@ -78706,7 +80495,7 @@
   if( pAccum ){
     sqlite3 *db = sqlite3_context_db_handle(context);
     int firstTerm = pAccum->useMalloc==0;
-    pAccum->useMalloc = 1;
+    pAccum->useMalloc = 2;
     pAccum->mxAlloc = db->aLimit[SQLITE_LIMIT_LENGTH];
     if( !firstTerm ){
       if( argc==2 ){
@@ -78775,10 +80564,10 @@
   }else{
     pInfo = (struct compareInfo*)&likeInfoNorm;
   }
-  sqlite3CreateFunc(db, "like", 2, SQLITE_ANY, pInfo, likeFunc, 0, 0);
-  sqlite3CreateFunc(db, "like", 3, SQLITE_ANY, pInfo, likeFunc, 0, 0);
+  sqlite3CreateFunc(db, "like", 2, SQLITE_ANY, pInfo, likeFunc, 0, 0, 0);
+  sqlite3CreateFunc(db, "like", 3, SQLITE_ANY, pInfo, likeFunc, 0, 0, 0);
   sqlite3CreateFunc(db, "glob", 2, SQLITE_ANY, 
-      (struct compareInfo*)&globInfo, likeFunc, 0,0);
+      (struct compareInfo*)&globInfo, likeFunc, 0, 0, 0);
   setLikeOptFlag(db, "glob", SQLITE_FUNC_LIKE | SQLITE_FUNC_CASE);
   setLikeOptFlag(db, "like", 
       caseSensitive ? (SQLITE_FUNC_LIKE | SQLITE_FUNC_CASE) : SQLITE_FUNC_LIKE);
@@ -79303,7 +81092,7 @@
       sqlite3VdbeAddOp3(v, OP_OpenRead, iCur, pIdx->tnum, iDb);
       sqlite3VdbeChangeP4(v, -1, (char*)pKey, P4_KEYINFO_HANDOFF);
       for(i=0; i<nCol; i++){
-        sqlite3VdbeAddOp2(v, OP_SCopy, aiCol[i]+1+regData, regTemp+i);
+        sqlite3VdbeAddOp2(v, OP_Copy, aiCol[i]+1+regData, regTemp+i);
       }
   
       /* If the parent table is the same as the child table, and we are about
@@ -79423,7 +81212,8 @@
       if( pIdx ){
         Column *pCol;
         iCol = pIdx->aiColumn[i];
-        pCol = &pIdx->pTable->aCol[iCol];
+        pCol = &pTab->aCol[iCol];
+        if( pTab->iPKey==iCol ) iCol = -1;
         pLeft->iTable = regData+iCol+1;
         pLeft->affinity = pCol->affinity;
         pLeft->pColl = sqlite3LocateCollSeq(pParse, pCol->zColl);
@@ -79984,11 +81774,7 @@
       pWhere = 0;
     }
 
-    /* In the current implementation, pTab->dbMem==0 for all tables except
-    ** for temporary tables used to describe subqueries.  And temporary
-    ** tables do not have foreign key constraints.  Hence, pTab->dbMem
-    ** should always be 0 there.
-    */
+    /* Disable lookaside memory allocation */
     enableLookaside = db->lookaside.bEnabled;
     db->lookaside.bEnabled = 0;
 
@@ -80078,37 +81864,39 @@
 ** table pTab. Remove the deleted foreign keys from the Schema.fkeyHash
 ** hash table.
 */
-SQLITE_PRIVATE void sqlite3FkDelete(Table *pTab){
+SQLITE_PRIVATE void sqlite3FkDelete(sqlite3 *db, Table *pTab){
   FKey *pFKey;                    /* Iterator variable */
   FKey *pNext;                    /* Copy of pFKey->pNextFrom */
 
   for(pFKey=pTab->pFKey; pFKey; pFKey=pNext){
 
     /* Remove the FK from the fkeyHash hash table. */
-    if( pFKey->pPrevTo ){
-      pFKey->pPrevTo->pNextTo = pFKey->pNextTo;
-    }else{
-      void *data = (void *)pFKey->pNextTo;
-      const char *z = (data ? pFKey->pNextTo->zTo : pFKey->zTo);
-      sqlite3HashInsert(&pTab->pSchema->fkeyHash, z, sqlite3Strlen30(z), data);
+    if( !db || db->pnBytesFreed==0 ){
+      if( pFKey->pPrevTo ){
+        pFKey->pPrevTo->pNextTo = pFKey->pNextTo;
+      }else{
+        void *p = (void *)pFKey->pNextTo;
+        const char *z = (p ? pFKey->pNextTo->zTo : pFKey->zTo);
+        sqlite3HashInsert(&pTab->pSchema->fkeyHash, z, sqlite3Strlen30(z), p);
+      }
+      if( pFKey->pNextTo ){
+        pFKey->pNextTo->pPrevTo = pFKey->pPrevTo;
+      }
     }
-    if( pFKey->pNextTo ){
-      pFKey->pNextTo->pPrevTo = pFKey->pPrevTo;
-    }
-
-    /* Delete any triggers created to implement actions for this FK. */
-#ifndef SQLITE_OMIT_TRIGGER
-    fkTriggerDelete(pTab->dbMem, pFKey->apTrigger[0]);
-    fkTriggerDelete(pTab->dbMem, pFKey->apTrigger[1]);
-#endif
 
     /* EV: R-30323-21917 Each foreign key constraint in SQLite is
     ** classified as either immediate or deferred.
     */
     assert( pFKey->isDeferred==0 || pFKey->isDeferred==1 );
 
+    /* Delete any triggers created to implement actions for this FK. */
+#ifndef SQLITE_OMIT_TRIGGER
+    fkTriggerDelete(db, pFKey->apTrigger[0]);
+    fkTriggerDelete(db, pFKey->apTrigger[1]);
+#endif
+
     pNext = pFKey->pNextFrom;
-    sqlite3DbFree(pTab->dbMem, pFKey);
+    sqlite3DbFree(db, pFKey);
   }
 }
 #endif /* ifndef SQLITE_OMIT_FOREIGN_KEY */
@@ -80183,7 +81971,7 @@
     int n;
     Table *pTab = pIdx->pTable;
     sqlite3 *db = sqlite3VdbeDb(v);
-    pIdx->zColAff = (char *)sqlite3Malloc(pIdx->nColumn+2);
+    pIdx->zColAff = (char *)sqlite3DbMallocRaw(0, pIdx->nColumn+2);
     if( !pIdx->zColAff ){
       db->mallocFailed = 1;
       return 0;
@@ -80225,7 +82013,7 @@
     int i;
     sqlite3 *db = sqlite3VdbeDb(v);
 
-    zColAff = (char *)sqlite3Malloc(pTab->nCol+1);
+    zColAff = (char *)sqlite3DbMallocRaw(0, pTab->nCol+1);
     if( !zColAff ){
       db->mallocFailed = 1;
       return;
@@ -81336,6 +83124,7 @@
     if( onError==OE_Ignore ){
       sqlite3VdbeAddOp2(v, OP_Goto, 0, ignoreDest);
     }else{
+      if( onError==OE_Replace ) onError = OE_Abort; /* IMP: R-15569-63625 */
       sqlite3HaltConstraint(pParse, onError, 0, 0);
     }
     sqlite3VdbeResolveLabel(v, allOk);
@@ -82850,13 +84639,11 @@
   handle = sqlite3OsDlOpen(pVfs, zFile);
   if( handle==0 ){
     if( pzErrMsg ){
-      zErrmsg = sqlite3StackAllocZero(db, nMsg);
+      *pzErrMsg = zErrmsg = sqlite3_malloc(nMsg);
       if( zErrmsg ){
         sqlite3_snprintf(nMsg, zErrmsg, 
             "unable to open shared library [%s]", zFile);
         sqlite3OsDlError(pVfs, nMsg-1, zErrmsg);
-        *pzErrMsg = sqlite3DbStrDup(0, zErrmsg);
-        sqlite3StackFree(db, zErrmsg);
       }
     }
     return SQLITE_ERROR;
@@ -82865,13 +84652,11 @@
                    sqlite3OsDlSym(pVfs, handle, zProc);
   if( xInit==0 ){
     if( pzErrMsg ){
-      zErrmsg = sqlite3StackAllocZero(db, nMsg);
+      *pzErrMsg = zErrmsg = sqlite3_malloc(nMsg);
       if( zErrmsg ){
         sqlite3_snprintf(nMsg, zErrmsg,
             "no entry point [%s] in shared library [%s]", zProc,zFile);
         sqlite3OsDlError(pVfs, nMsg-1, zErrmsg);
-        *pzErrMsg = sqlite3DbStrDup(0, zErrmsg);
-        sqlite3StackFree(db, zErrmsg);
       }
       sqlite3OsDlClose(pVfs, handle);
     }
@@ -83620,8 +85405,11 @@
   **                      (delete|persist|off|truncate|memory|wal|off)
   */
   if( sqlite3StrICmp(zLeft,"journal_mode")==0 ){
-    int eMode;                    /* One of the PAGER_JOURNALMODE_XXX symbols */
+    int eMode;        /* One of the PAGER_JOURNALMODE_XXX symbols */
+    int ii;           /* Loop counter */
 
+    /* Force the schema to be loaded on all databases.  This cases all
+    ** database files to be opened and the journal_modes set. */
     if( sqlite3ReadSchema(pParse) ){
       goto pragma_out;
     }
@@ -83630,6 +85418,8 @@
     sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "journal_mode", SQLITE_STATIC);
 
     if( zRight==0 ){
+      /* If there is no "=MODE" part of the pragma, do a query for the
+      ** current mode */
       eMode = PAGER_JOURNALMODE_QUERY;
     }else{
       const char *zMode;
@@ -83638,40 +85428,22 @@
         if( sqlite3StrNICmp(zRight, zMode, n)==0 ) break;
       }
       if( !zMode ){
+        /* If the "=MODE" part does not match any known journal mode,
+        ** then do a query */
         eMode = PAGER_JOURNALMODE_QUERY;
       }
     }
-    if( pId2->n==0 && eMode==PAGER_JOURNALMODE_QUERY ){
-      /* Simple "PRAGMA journal_mode;" statement. This is a query for
-      ** the current default journal mode (which may be different to
-      ** the journal-mode of the main database).
-      */
-      eMode = db->dfltJournalMode;
-      sqlite3VdbeAddOp2(v, OP_String8, 0, 1);
-      sqlite3VdbeChangeP4(v, -1, sqlite3JournalModename(eMode), P4_STATIC);
-    }else{
-      int ii;
-
-      if( pId2->n==0 ){
-        /* When there is no database name before the "journal_mode" keyword
-        ** in the PRAGMA, then the journal-mode will be set on
-        ** all attached databases, as well as the main db file.
-        **
-        ** Also, the sqlite3.dfltJournalMode variable is set so that
-        ** any subsequently attached databases also use the specified
-        ** journal mode.
-        */
-        db->dfltJournalMode = (u8)eMode;
-      }
-
-      for(ii=db->nDb-1; ii>=0; ii--){
-        if( db->aDb[ii].pBt && (ii==iDb || pId2->n==0) ){
-          sqlite3VdbeUsesBtree(v, ii);
-          sqlite3VdbeAddOp3(v, OP_JournalMode, ii, 1, eMode);
-        }
+    if( eMode==PAGER_JOURNALMODE_QUERY && pId2->n==0 ){
+      /* Convert "PRAGMA journal_mode" into "PRAGMA main.journal_mode" */
+      iDb = 0;
+      pId2->n = 1;
+    }
+    for(ii=db->nDb-1; ii>=0; ii--){
+      if( db->aDb[ii].pBt && (ii==iDb || pId2->n==0) ){
+        sqlite3VdbeUsesBtree(v, ii);
+        sqlite3VdbeAddOp3(v, OP_JournalMode, ii, 1, eMode);
       }
     }
-
     sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
   }else
 
@@ -83863,7 +85635,7 @@
       }
       sqlite3_free(sqlite3_temp_directory);
       if( zRight[0] ){
-        sqlite3_temp_directory = sqlite3DbStrDup(0, zRight);
+        sqlite3_temp_directory = sqlite3_mprintf("%s", zRight);
       }else{
         sqlite3_temp_directory = 0;
       }
@@ -85284,7 +87056,6 @@
   while( pParse->pTriggerPrg ){
     TriggerPrg *pT = pParse->pTriggerPrg;
     pParse->pTriggerPrg = pT->pNext;
-    sqlite3VdbeProgramDelete(db, pT->pProgram, 0);
     sqlite3DbFree(db, pT);
   }
 
@@ -85968,11 +87739,13 @@
   sqlite3ReleaseTempReg(pParse, r1);
 }
 
+#ifndef SQLITE_OMIT_SUBQUERY
 /*
 ** Generate an error message when a SELECT is used within a subexpression
 ** (example:  "a IN (SELECT * FROM table)") but it has more than 1 result
-** column.  We do this in a subroutine because the error occurs in multiple
-** places.
+** column.  We do this in a subroutine because the error used to occur
+** in multiple places.  (The error only occurs in one place now, but we
+** retain the subroutine to minimize code disruption.)
 */
 static int checkForMultiColumnSelectError(
   Parse *pParse,       /* Parse context. */
@@ -85988,6 +87761,7 @@
     return 0;
   }
 }
+#endif
 
 /*
 ** This routine generates the code for the inside of the inner loop
@@ -86067,10 +87841,6 @@
     }
   }
 
-  if( checkForMultiColumnSelectError(pParse, pDest, pEList->nExpr) ){
-    return;
-  }
-
   switch( eDest ){
     /* In this mode, write each query result to the key of the temporary
     ** table iParm.
@@ -86775,16 +88545,15 @@
     return 0;
   }
   /* The sqlite3ResultSetOfSelect() is only used n contexts where lookaside
-  ** is disabled, so we might as well hard-code pTab->dbMem to NULL. */
+  ** is disabled */
   assert( db->lookaside.bEnabled==0 );
-  pTab->dbMem = 0;
   pTab->nRef = 1;
   pTab->zName = 0;
   selectColumnsFromExprList(pParse, pSelect->pEList, &pTab->nCol, &pTab->aCol);
   selectAddColumnTypeAndCollation(pParse, pTab->nCol, pTab->aCol, pSelect);
   pTab->iPKey = -1;
   if( db->mallocFailed ){
-    sqlite3DeleteTable(pTab);
+    sqlite3DeleteTable(db, pTab);
     return 0;
   }
   return pTab;
@@ -86981,6 +88750,7 @@
   if( dest.eDest==SRT_EphemTab ){
     assert( p->pEList );
     sqlite3VdbeAddOp2(v, OP_OpenEphemeral, dest.iParm, p->pEList->nExpr);
+    sqlite3VdbeChangeP5(v, BTREE_UNORDERED);
     dest.eDest = SRT_Table;
   }
 
@@ -87276,7 +89046,7 @@
 ** regReturn is the number of the register holding the subroutine
 ** return address.
 **
-** If regPrev>0 then it is a the first register in a vector that
+** If regPrev>0 then it is the first register in a vector that
 ** records the previous output.  mem[regPrev] is a flag that is false
 ** if there has been no previous output.  If regPrev>0 then code is
 ** generated to suppress duplicates.  pKeyInfo is used for comparing
@@ -87973,12 +89743,13 @@
 **   (2)  The subquery is not an aggregate or the outer query is not a join.
 **
 **   (3)  The subquery is not the right operand of a left outer join
-**        (Originally ticket #306.  Strenghtened by ticket #3300)
+**        (Originally ticket #306.  Strengthened by ticket #3300)
 **
-**   (4)  The subquery is not DISTINCT or the outer query is not a join.
+**   (4)  The subquery is not DISTINCT.
 **
-**   (5)  The subquery is not DISTINCT or the outer query does not use
-**        aggregates.
+**  (**)  At one point restrictions (4) and (5) defined a subset of DISTINCT
+**        sub-queries that were excluded from this optimization. Restriction 
+**        (4) has since been expanded to exclude all DISTINCT subqueries.
 **
 **   (6)  The subquery does not use aggregates or the outer query is not
 **        DISTINCT.
@@ -87998,9 +89769,9 @@
 **  (**)  Not implemented.  Subsumed into restriction (3).  Was previously
 **        a separate restriction deriving from ticket #350.
 **
-**  (13)  The subquery and outer query do not both use LIMIT
+**  (13)  The subquery and outer query do not both use LIMIT.
 **
-**  (14)  The subquery does not use OFFSET
+**  (14)  The subquery does not use OFFSET.
 **
 **  (15)  The outer query is not part of a compound select or the
 **        subquery does not have a LIMIT clause.
@@ -88091,9 +89862,9 @@
     return 0;                                            /* Restriction (15) */
   }
   if( pSubSrc->nSrc==0 ) return 0;                       /* Restriction (7)  */
-  if( ((pSub->selFlags & SF_Distinct)!=0 || pSub->pLimit) 
-         && (pSrc->nSrc>1 || isAgg) ){          /* Restrictions (4)(5)(8)(9) */
-     return 0;       
+  if( pSub->selFlags & SF_Distinct ) return 0;           /* Restriction (5)  */
+  if( pSub->pLimit && (pSrc->nSrc>1 || isAgg) ){
+     return 0;         /* Restrictions (8)(9) */
   }
   if( (p->selFlags & SF_Distinct)!=0 && subqueryIsAgg ){
      return 0;         /* Restriction (6)  */
@@ -88573,7 +90344,6 @@
       sqlite3WalkSelect(pWalker, pSel);
       pFrom->pTab = pTab = sqlite3DbMallocZero(db, sizeof(Table));
       if( pTab==0 ) return WRC_Abort;
-      pTab->dbMem = db->lookaside.bEnabled ? db : 0;
       pTab->nRef = 1;
       pTab->zName = sqlite3MPrintf(db, "sqlite_subquery_%p_", (void*)pTab);
       while( pSel->pPrior ){ pSel = pSel->pPrior; }
@@ -88943,7 +90713,7 @@
     if( pList ){
       nArg = pList->nExpr;
       regAgg = sqlite3GetTempRange(pParse, nArg);
-      sqlite3ExprCodeExprList(pParse, pList, regAgg, 0);
+      sqlite3ExprCodeExprList(pParse, pList, regAgg, 1);
     }else{
       nArg = 0;
       regAgg = 0;
@@ -89103,6 +90873,15 @@
   v = sqlite3GetVdbe(pParse);
   if( v==0 ) goto select_end;
 
+  /* If writing to memory or generating a set
+  ** only a single column may be output.
+  */
+#ifndef SQLITE_OMIT_SUBQUERY
+  if( checkForMultiColumnSelectError(pParse, pDest, pEList->nExpr) ){
+    goto select_end;
+  }
+#endif
+
   /* Generate code for all sub-queries in the FROM clause
   */
 #if !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW)
@@ -89176,15 +90955,6 @@
   }
 #endif
 
-  /* If writing to memory or generating a set
-  ** only a single column may be output.
-  */
-#ifndef SQLITE_OMIT_SUBQUERY
-  if( checkForMultiColumnSelectError(pParse, pDest, pEList->nExpr) ){
-    goto select_end;
-  }
-#endif
-
   /* If possible, rewrite the query to use GROUP BY instead of DISTINCT.
   ** GROUP BY might use an index, DISTINCT never does.
   */
@@ -89247,6 +91017,7 @@
     pKeyInfo = keyInfoFromExprList(pParse, p->pEList);
     sqlite3VdbeAddOp4(v, OP_OpenEphemeral, distinct, 0, 0,
                         (char*)pKeyInfo, P4_KEYINFO_HANDOFF);
+    sqlite3VdbeChangeP5(v, BTREE_UNORDERED);
   }else{
     distinct = -1;
   }
@@ -90787,6 +92558,7 @@
   int iEndTrigger = 0;        /* Label to jump to if WHEN is false */
 
   assert( pTrigger->zName==0 || pTab==tableOfTrigger(pTrigger) );
+  assert( pTop->pVdbe );
 
   /* Allocate the TriggerPrg and SubProgram objects. To ensure that they
   ** are freed if an error occurs, link them into the Parse.pTriggerPrg 
@@ -90797,7 +92569,7 @@
   pTop->pTriggerPrg = pPrg;
   pPrg->pProgram = pProgram = sqlite3DbMallocZero(db, sizeof(SubProgram));
   if( !pProgram ) return 0;
-  pProgram->nRef = 1;
+  sqlite3VdbeLinkSubProgram(pTop->pVdbe, pProgram);
   pPrg->pTrigger = pTrigger;
   pPrg->orconf = orconf;
   pPrg->aColmask[0] = 0xffffffff;
@@ -90931,8 +92703,9 @@
   /* Code the OP_Program opcode in the parent VDBE. P4 of the OP_Program 
   ** is a pointer to the sub-vdbe containing the trigger program.  */
   if( pPrg ){
+    int bRecursive = (p->zName && 0==(pParse->db->flags&SQLITE_RecTriggers));
+
     sqlite3VdbeAddOp3(v, OP_Program, reg, ignoreJump, ++pParse->nMem);
-    pPrg->pProgram->nRef++;
     sqlite3VdbeChangeP4(v, -1, (const char *)pPrg->pProgram, P4_SUBPROGRAM);
     VdbeComment(
         (v, "Call: %s.%s", (p->zName?p->zName:"fkey"), onErrorText(orconf)));
@@ -90942,7 +92715,7 @@
     ** invocation is disallowed if (a) the sub-program is really a trigger,
     ** not a foreign key action, and (b) the flag to enable recursive triggers
     ** is clear.  */
-    sqlite3VdbeChangeP5(v, (u8)(p->zName && !(pParse->db->flags&SQLITE_RecTriggers)));
+    sqlite3VdbeChangeP5(v, (u8)bRecursive);
   }
 }
 
@@ -91091,7 +92864,7 @@
 **    May you find forgiveness for yourself and forgive others.
 **    May you share freely, never taking more than you give.
 **
-sqlite*************************************************************************
+*************************************************************************
 ** This file contains C code routines that are called by the parser
 ** to handle UPDATE statements.
 */
@@ -91720,6 +93493,7 @@
   assert( v );
   ephemTab = pParse->nTab++;
   sqlite3VdbeAddOp2(v, OP_OpenEphemeral, ephemTab, pTab->nCol+1+(pRowid!=0));
+  sqlite3VdbeChangeP5(v, BTREE_UNORDERED);
 
   /* fill the ephemeral table 
   */
@@ -91859,6 +93633,10 @@
     sqlite3SetString(pzErrMsg, db, "cannot VACUUM from within a transaction");
     return SQLITE_ERROR;
   }
+  if( db->activeVdbeCnt>1 ){
+    sqlite3SetString(pzErrMsg, db,"cannot VACUUM - SQL statements in progress");
+    return SQLITE_ERROR;
+  }
 
   /* Save the current value of the database flags so that it can be 
   ** restored before returning. Then set the writable-schema flag, and
@@ -92310,14 +94088,14 @@
 ** in the list are moved to the sqlite3.pDisconnect list of the associated 
 ** database connection.
 */
-SQLITE_PRIVATE void sqlite3VtabClear(Table *p){
-  vtabDisconnectAll(0, p);
+SQLITE_PRIVATE void sqlite3VtabClear(sqlite3 *db, Table *p){
+  if( !db || db->pnBytesFreed==0 ) vtabDisconnectAll(0, p);
   if( p->azModuleArg ){
     int i;
     for(i=0; i<p->nModuleArg; i++){
-      sqlite3DbFree(p->dbMem, p->azModuleArg[i]);
+      sqlite3DbFree(db, p->azModuleArg[i]);
     }
-    sqlite3DbFree(p->dbMem, p->azModuleArg);
+    sqlite3DbFree(db, p->azModuleArg);
   }
 }
 
@@ -92482,7 +94260,6 @@
       assert( pTab==pOld );  /* Malloc must have failed inside HashInsert() */
       return;
     }
-    pSchema->db = pParse->db;
     pParse->pNewTable = 0;
   }
 }
@@ -92556,7 +94333,7 @@
       *pzErr = sqlite3MPrintf(db, "vtable constructor failed: %s", zModuleName);
     }else {
       *pzErr = sqlite3MPrintf(db, "%s", zErr);
-      sqlite3DbFree(db, zErr);
+      sqlite3_free(zErr);
     }
     sqlite3DbFree(db, pVTable);
   }else if( ALWAYS(pVTable->pVtab) ){
@@ -92771,7 +94548,7 @@
     if( pParse->pVdbe ){
       sqlite3VdbeFinalize(pParse->pVdbe);
     }
-    sqlite3DeleteTable(pParse->pNewTable);
+    sqlite3DeleteTable(db, pParse->pNewTable);
     sqlite3StackFree(db, pParse);
   }
 
@@ -92858,8 +94635,8 @@
     if( pVtab && (x = pVtab->pModule->xSync)!=0 ){
       rc = x(pVtab);
       sqlite3DbFree(db, *pzErrmsg);
-      *pzErrmsg = pVtab->zErrMsg;
-      pVtab->zErrMsg = 0;
+      *pzErrmsg = sqlite3DbStrDup(db, pVtab->zErrMsg);
+      sqlite3_free(pVtab->zErrMsg);
     }
   }
   db->aVTrans = aVTrans;
@@ -93359,6 +95136,7 @@
 static int whereClauseInsert(WhereClause *pWC, Expr *p, u8 wtFlags){
   WhereTerm *pTerm;
   int idx;
+  testcase( wtFlags & TERM_VIRTUAL );  /* EV: R-00211-15100 */
   if( pWC->nTerm>=pWC->nSlot ){
     WhereTerm *pOld = pWC->a;
     sqlite3 *db = pWC->pParse->db;
@@ -93504,6 +95282,13 @@
 ** Return TRUE if the given operator is one of the operators that is
 ** allowed for an indexable WHERE clause term.  The allowed operators are
 ** "=", "<", ">", "<=", ">=", and "IN".
+**
+** IMPLEMENTATION-OF: R-59926-26393 To be usable by an index a term must be
+** of one of the following forms: column = expression column > expression
+** column >= expression column < expression column <= expression
+** expression = column expression > column expression >= column
+** expression < column expression <= column column IN
+** (expression-list) column IN (subquery) column IS NULL
 */
 static int allowedOp(int op){
   assert( TK_GT>TK_EQ && TK_GT<TK_GE );
@@ -93667,7 +95452,6 @@
   int c;                     /* One character in z[] */
   int cnt;                   /* Number of non-wildcard prefix characters */
   char wc[3];                /* Wildcard characters */
-  CollSeq *pColl;            /* Collating sequence for LHS */
   sqlite3 *db = pParse->db;  /* Database connection */
   sqlite3_value *pVal = 0;
   int op;                    /* Opcode of pRight */
@@ -93686,19 +95470,6 @@
     return 0;
   }
   assert( pLeft->iColumn!=(-1) ); /* Because IPK never has AFF_TEXT */
-  pColl = sqlite3ExprCollSeq(pParse, pLeft);
-  if( pColl==0 ) return 0;  /* Happens when LHS has an undefined collation */
-  if( (pColl->type!=SQLITE_COLL_BINARY || *pnoCase) &&
-      (pColl->type!=SQLITE_COLL_NOCASE || !*pnoCase) ){
-    /* IMP: R-09003-32046 For the GLOB operator, the column must use the
-    ** default BINARY collating sequence.
-    ** IMP: R-41408-28306 For the LIKE operator, if case_sensitive_like mode
-    ** is enabled then the column must use the default BINARY collating
-    ** sequence, or if case_sensitive_like mode is disabled then the column
-    ** must use the built-in NOCASE collating sequence.
-    */
-    return 0;
-  }
 
   pRight = pList->a[0].pExpr;
   op = pRight->op;
@@ -93707,11 +95478,12 @@
   }
   if( op==TK_VARIABLE ){
     Vdbe *pReprepare = pParse->pReprepare;
-    pVal = sqlite3VdbeGetValue(pReprepare, pRight->iColumn, SQLITE_AFF_NONE);
+    int iCol = pRight->iColumn;
+    pVal = sqlite3VdbeGetValue(pReprepare, iCol, SQLITE_AFF_NONE);
     if( pVal && sqlite3_value_type(pVal)==SQLITE_TEXT ){
       z = (char *)sqlite3_value_text(pVal);
     }
-    sqlite3VdbeSetVarmask(pParse->pVdbe, pRight->iColumn);
+    sqlite3VdbeSetVarmask(pParse->pVdbe, iCol); /* IMP: R-23257-02778 */
     assert( pRight->op==TK_VARIABLE || pRight->op==TK_REGISTER );
   }else if( op==TK_STRING ){
     z = pRight->u.zToken;
@@ -93721,15 +95493,15 @@
     while( (c=z[cnt])!=0 && c!=wc[0] && c!=wc[1] && c!=wc[2] ){
       cnt++;
     }
-    if( cnt!=0 && c!=0 && 255!=(u8)z[cnt-1] ){
+    if( cnt!=0 && 255!=(u8)z[cnt-1] ){
       Expr *pPrefix;
-      *pisComplete = z[cnt]==wc[0] && z[cnt+1]==0;
+      *pisComplete = c==wc[0] && z[cnt+1]==0;
       pPrefix = sqlite3Expr(db, TK_STRING, z);
       if( pPrefix ) pPrefix->u.zToken[cnt] = 0;
       *ppPrefix = pPrefix;
       if( op==TK_VARIABLE ){
         Vdbe *v = pParse->pVdbe;
-        sqlite3VdbeSetVarmask(v, pRight->iColumn);
+        sqlite3VdbeSetVarmask(v, pRight->iColumn); /* IMP: R-23257-02778 */
         if( *pisComplete && pRight->u.zToken[1] ){
           /* If the rhs of the LIKE expression is a variable, and the current
           ** value of the variable means there is no need to invoke the LIKE
@@ -94062,6 +95834,8 @@
     /* At this point, okToChngToIN is true if original pTerm satisfies
     ** case 1.  In that case, construct a new virtual term that is 
     ** pTerm converted into an IN operator.
+    **
+    ** EV: R-00211-15100
     */
     if( okToChngToIN ){
       Expr *pDup;            /* A transient duplicate expression */
@@ -94278,6 +96052,7 @@
     Expr *pNewExpr2;
     int idxNew1;
     int idxNew2;
+    CollSeq *pColl;    /* Collating sequence to use */
 
     pLeft = pExpr->x.pList->a[1].pExpr;
     pStr2 = sqlite3ExprDup(db, pStr1, 0);
@@ -94292,17 +96067,23 @@
         ** inequality.  To avoid this, make sure to also run the full
         ** LIKE on all candidate expressions by clearing the isComplete flag
         */
-        if( c=='A'-1 ) isComplete = 0;
+        if( c=='A'-1 ) isComplete = 0;   /* EV: R-64339-08207 */
+
 
         c = sqlite3UpperToLower[c];
       }
       *pC = c + 1;
     }
-    pNewExpr1 = sqlite3PExpr(pParse, TK_GE, sqlite3ExprDup(db,pLeft,0),pStr1,0);
+    pColl = sqlite3FindCollSeq(db, SQLITE_UTF8, noCase ? "NOCASE" : "BINARY",0);
+    pNewExpr1 = sqlite3PExpr(pParse, TK_GE, 
+                     sqlite3ExprSetColl(sqlite3ExprDup(db,pLeft,0), pColl),
+                     pStr1, 0);
     idxNew1 = whereClauseInsert(pWC, pNewExpr1, TERM_VIRTUAL|TERM_DYNAMIC);
     testcase( idxNew1==0 );
     exprAnalyze(pSrc, pWC, idxNew1);
-    pNewExpr2 = sqlite3PExpr(pParse, TK_LT, sqlite3ExprDup(db,pLeft,0),pStr2,0);
+    pNewExpr2 = sqlite3PExpr(pParse, TK_LT,
+                     sqlite3ExprSetColl(sqlite3ExprDup(db,pLeft,0), pColl),
+                     pStr2, 0);
     idxNew2 = whereClauseInsert(pWC, pNewExpr2, TERM_VIRTUAL|TERM_DYNAMIC);
     testcase( idxNew2==0 );
     exprAnalyze(pSrc, pWC, idxNew2);
@@ -94734,7 +96515,7 @@
 
   assert( pParse->nQueryLoop >= (double)1 );
   pTable = pSrc->pTab;
-  nTableRow = pTable->pIndex ? pTable->pIndex->aiRowEst[0] : 1000000;
+  nTableRow = pTable->nRowEst;
   logN = estLog(nTableRow);
   costTempIdx = 2*logN*(nTableRow/pParse->nQueryLoop + 1);
   if( costTempIdx>=pCost->rCost ){
@@ -95054,7 +96835,7 @@
       sqlite3ErrorMsg(pParse, "%s", pVtab->zErrMsg);
     }
   }
-  sqlite3DbFree(pParse->db, pVtab->zErrMsg);
+  sqlite3_free(pVtab->zErrMsg);
   pVtab->zErrMsg = 0;
 
   for(i=0; i<p->nConstraint; i++){
@@ -95344,7 +97125,7 @@
   assert( pExpr->op!=TK_VARIABLE );
   if( pExpr->op==TK_REGISTER && pExpr->op2==TK_VARIABLE ){
     int iVar = pExpr->iColumn;
-    sqlite3VdbeSetVarmask(pParse->pVdbe, iVar);
+    sqlite3VdbeSetVarmask(pParse->pVdbe, iVar); /* IMP: R-23257-02778 */
     *pp = sqlite3VdbeGetValue(pParse->pReprepare, iVar, aff);
     return SQLITE_OK;
   }
@@ -95541,23 +97322,14 @@
     sPk.nColumn = 1;
     sPk.aiColumn = &aiColumnPk;
     sPk.aiRowEst = aiRowEstPk;
-    aiRowEstPk[1] = 1;
     sPk.onError = OE_Replace;
     sPk.pTable = pSrc->pTab;
+    aiRowEstPk[0] = pSrc->pTab->nRowEst;
+    aiRowEstPk[1] = 1;
     pFirst = pSrc->pTab->pIndex;
     if( pSrc->notIndexed==0 ){
       sPk.pNext = pFirst;
     }
-    /* The aiRowEstPk[0] is an estimate of the total number of rows in the
-    ** table.  Get this information from the ANALYZE information if it is
-    ** available.  If not available, assume the table 1 million rows in size.
-    */
-    if( pFirst ){
-      assert( pFirst->aiRowEst!=0 ); /* Allocated together with pFirst */
-      aiRowEstPk[0] = pFirst->aiRowEst[0];
-    }else{
-      aiRowEstPk[0] = 1000000;
-    }
     pProbe = &sPk;
     wsFlagMask = ~(
         WHERE_COLUMN_IN|WHERE_COLUMN_EQ|WHERE_COLUMN_NULL|WHERE_COLUMN_RANGE
@@ -95654,7 +97426,7 @@
         if( ExprHasProperty(pExpr, EP_xIsSelect) ){
           nInMul *= 25;
           bInEst = 1;
-        }else if( pExpr->x.pList ){
+        }else if( ALWAYS(pExpr->x.pList) ){
           nInMul *= pExpr->x.pList->nExpr + 1;
         }
       }else if( pTerm->eOperator & WO_ISNULL ){
@@ -95919,6 +97691,9 @@
 ** in the ON clause.  The term is disabled in (3) because it is not part
 ** of a LEFT OUTER JOIN.  In (1), the term is not disabled.
 **
+** IMPLEMENTATION-OF: R-24597-58655 No tests are done for terms that are
+** completely satisfied by indices.
+**
 ** Disabling a term causes that term to not be tested in the inner loop
 ** of the join.  Disabling is an optimization.  When terms are satisfied
 ** by indices, we disable them to prevent redundant tests in the inner
@@ -96130,6 +97905,7 @@
     /* The following true for indices with redundant columns. 
     ** Ex: CREATE INDEX i1 ON t1(a,b,a); SELECT * FROM t1 WHERE a=0 AND b=0; */
     testcase( (pTerm->wtFlags & TERM_CODED)!=0 );
+    testcase( pTerm->wtFlags & TERM_VIRTUAL ); /* EV: R-30575-11662 */
     r1 = codeEqualityTerm(pParse, pTerm, pLevel, regBase+j);
     if( r1!=regBase+j ){
       if( nReg==1 ){
@@ -96273,6 +98049,7 @@
     assert( pTerm->pExpr!=0 );
     assert( pTerm->leftCursor==iCur );
     assert( omitTable==0 );
+    testcase( pTerm->wtFlags & TERM_VIRTUAL ); /* EV: R-30575-11662 */
     iRowidReg = codeEqualityTerm(pParse, pTerm, pLevel, iReleaseReg);
     addrNxt = pLevel->addrNxt;
     sqlite3VdbeAddOp2(v, OP_MustBeInt, iRowidReg, addrNxt);
@@ -96313,6 +98090,7 @@
       assert( TK_LT==TK_GT+2 );      /*  ... of the TK_xx values... */
       assert( TK_GE==TK_GT+3 );      /*  ... is correcct. */
 
+      testcase( pStart->wtFlags & TERM_VIRTUAL ); /* EV: R-30575-11662 */
       pX = pStart->pExpr;
       assert( pX!=0 );
       assert( pStart->leftCursor==iCur );
@@ -96330,6 +98108,7 @@
       pX = pEnd->pExpr;
       assert( pX!=0 );
       assert( pEnd->leftCursor==iCur );
+      testcase( pEnd->wtFlags & TERM_VIRTUAL ); /* EV: R-30575-11662 */
       memEndValue = ++pParse->nMem;
       sqlite3ExprCode(pParse, pX->pRight, memEndValue);
       if( pX->op==TK_LT || pX->op==TK_GT ){
@@ -96387,7 +98166,7 @@
     **         constraints but an index is selected anyway, in order
     **         to force the output order to conform to an ORDER BY.
     */  
-    int aStartOp[] = {
+    static const u8 aStartOp[] = {
       0,
       0,
       OP_Rewind,           /* 2: (!start_constraints && startEq &&  !bRev) */
@@ -96397,12 +98176,12 @@
       OP_SeekGe,           /* 6: (start_constraints  &&  startEq && !bRev) */
       OP_SeekLe            /* 7: (start_constraints  &&  startEq &&  bRev) */
     };
-    int aEndOp[] = {
+    static const u8 aEndOp[] = {
       OP_Noop,             /* 0: (!end_constraints) */
       OP_IdxGE,            /* 1: (end_constraints && !bRev) */
       OP_IdxLT             /* 2: (end_constraints && bRev) */
     };
-    int nEq = pLevel->plan.nEq;
+    int nEq = pLevel->plan.nEq;  /* Number of == or IN terms */
     int isMinQuery = 0;          /* If this is an optimized SELECT min(x).. */
     int regBase;                 /* Base register holding constraint values */
     int r1;                      /* Temp register */
@@ -96412,10 +98191,10 @@
     int endEq;                   /* True if range end uses ==, >= or <= */
     int start_constraints;       /* Start of range is constrained */
     int nConstraint;             /* Number of constraint terms */
-    Index *pIdx;         /* The index we will be using */
-    int iIdxCur;         /* The VDBE cursor for the index */
-    int nExtraReg = 0;   /* Number of extra registers needed */
-    int op;              /* Instruction opcode */
+    Index *pIdx;                 /* The index we will be using */
+    int iIdxCur;                 /* The VDBE cursor for the index */
+    int nExtraReg = 0;           /* Number of extra registers needed */
+    int op;                      /* Instruction opcode */
     char *zStartAff;             /* Affinity for start of range constraint */
     char *zEndAff;               /* Affinity for end of range constraint */
 
@@ -96497,6 +98276,7 @@
         }
       }  
       nConstraint++;
+      testcase( pRangeStart->wtFlags & TERM_VIRTUAL ); /* EV: R-30575-11662 */
     }else if( isMinQuery ){
       sqlite3VdbeAddOp2(v, OP_Null, 0, regBase+nEq);
       nConstraint++;
@@ -96536,6 +98316,7 @@
       }  
       codeApplyAffinity(pParse, regBase, nEq+1, zEndAff);
       nConstraint++;
+      testcase( pRangeEnd->wtFlags & TERM_VIRTUAL ); /* EV: R-30575-11662 */
     }
     sqlite3DbFree(pParse->db, zStartAff);
     sqlite3DbFree(pParse->db, zEndAff);
@@ -96742,11 +98523,15 @@
 
   /* Insert code to test every subexpression that can be completely
   ** computed using the current set of tables.
+  **
+  ** IMPLEMENTATION-OF: R-49525-50935 Terms that cannot be satisfied through
+  ** the use of indices become tests that are evaluated against each row of
+  ** the relevant input tables.
   */
   k = 0;
   for(pTerm=pWC->a, j=pWC->nTerm; j>0; j--, pTerm++){
     Expr *pE;
-    testcase( pTerm->wtFlags & TERM_VIRTUAL );
+    testcase( pTerm->wtFlags & TERM_VIRTUAL ); /* IMP: R-30575-11662 */
     testcase( pTerm->wtFlags & TERM_CODED );
     if( pTerm->wtFlags & (TERM_VIRTUAL|TERM_CODED) ) continue;
     if( (pTerm->prereqAll & notReady)!=0 ){
@@ -96774,7 +98559,7 @@
     VdbeComment((v, "record LEFT JOIN hit"));
     sqlite3ExprCacheClear(pParse);
     for(pTerm=pWC->a, j=0; j<pWC->nTerm; j++, pTerm++){
-      testcase( pTerm->wtFlags & TERM_VIRTUAL );
+      testcase( pTerm->wtFlags & TERM_VIRTUAL );  /* IMP: R-30575-11662 */
       testcase( pTerm->wtFlags & TERM_CODED );
       if( pTerm->wtFlags & (TERM_VIRTUAL|TERM_CODED) ) continue;
       if( (pTerm->prereqAll & notReady)!=0 ){
@@ -96992,7 +98777,7 @@
   initMaskSet(pMaskSet);
   whereClauseInit(pWC, pParse, pMaskSet);
   sqlite3ExprCodeConstants(pParse, pWhere);
-  whereSplit(pWC, pWhere, TK_AND);
+  whereSplit(pWC, pWhere, TK_AND);   /* IMP: R-15842-53296 */
     
   /* Special case: a WHERE clause that is constant.  Evaluate the
   ** expression and either jump over all of the code or fall thru.
@@ -97080,6 +98865,8 @@
     int bestJ = -1;             /* The value of j */
     Bitmask m;                  /* Bitmask value for j or bestJ */
     int isOptimal;              /* Iterator for optimal/non-optimal search */
+    int nUnconstrained;         /* Number tables without INDEXED BY */
+    Bitmask notIndexed;         /* Mask of tables that cannot use an index */
 
     memset(&bestPlan, 0, sizeof(bestPlan));
     bestPlan.rCost = SQLITE_BIG_DBL;
@@ -97116,13 +98903,15 @@
     **
     ** The best strategy is to iterate through table t1 first. However it
     ** is not possible to determine this with a simple greedy algorithm.
-    ** However, since the cost of a linear scan through table t2 is the same 
+    ** Since the cost of a linear scan through table t2 is the same 
     ** as the cost of a linear scan through table t1, a simple greedy 
     ** algorithm may choose to use t2 for the outer loop, which is a much
     ** costlier approach.
     */
+    nUnconstrained = 0;
+    notIndexed = 0;
     for(isOptimal=(iFrom<nTabList-1); isOptimal>=0; isOptimal--){
-      Bitmask mask;  /* Mask of tables not yet ready */
+      Bitmask mask;             /* Mask of tables not yet ready */
       for(j=iFrom, pTabItem=&pTabList->a[j]; j<nTabList; j++, pTabItem++){
         int doNotReorder;    /* True if this table should not be reordered */
         WhereCost sCost;     /* Cost information from best[Virtual]Index() */
@@ -97137,6 +98926,7 @@
         }
         mask = (isOptimal ? m : notReady);
         pOrderBy = ((i==0 && ppOrderBy )?*ppOrderBy:0);
+        if( pTabItem->pIndex==0 ) nUnconstrained++;
   
         assert( pTabItem->pTab );
 #ifndef SQLITE_OMIT_VIRTUALTABLE
@@ -97150,9 +98940,43 @@
         }
         assert( isOptimal || (sCost.used&notReady)==0 );
 
-        if( (sCost.used&notReady)==0
-         && (bestJ<0 || sCost.rCost<bestPlan.rCost
-             || (sCost.rCost<=bestPlan.rCost && sCost.nRow<bestPlan.nRow))
+        /* If an INDEXED BY clause is present, then the plan must use that
+        ** index if it uses any index at all */
+        assert( pTabItem->pIndex==0 
+                  || (sCost.plan.wsFlags & WHERE_NOT_FULLSCAN)==0
+                  || sCost.plan.u.pIdx==pTabItem->pIndex );
+
+        if( isOptimal && (sCost.plan.wsFlags & WHERE_NOT_FULLSCAN)==0 ){
+          notIndexed |= m;
+        }
+
+        /* Conditions under which this table becomes the best so far:
+        **
+        **   (1) The table must not depend on other tables that have not
+        **       yet run.
+        **
+        **   (2) A full-table-scan plan cannot supercede another plan unless
+        **       it is an "optimal" plan as defined above.
+        **
+        **   (3) All tables have an INDEXED BY clause or this table lacks an
+        **       INDEXED BY clause or this table uses the specific
+        **       index specified by its INDEXED BY clause.  This rule ensures
+        **       that a best-so-far is always selected even if an impossible
+        **       combination of INDEXED BY clauses are given.  The error
+        **       will be detected and relayed back to the application later.
+        **       The NEVER() comes about because rule (2) above prevents
+        **       An indexable full-table-scan from reaching rule (3).
+        **
+        **   (4) The plan cost must be lower than prior plans or else the
+        **       cost must be the same and the number of rows must be lower.
+        */
+        if( (sCost.used&notReady)==0                       /* (1) */
+            && (bestJ<0 || (notIndexed&m)!=0               /* (2) */
+                || (sCost.plan.wsFlags & WHERE_NOT_FULLSCAN)!=0)
+            && (nUnconstrained==0 || pTabItem->pIndex==0   /* (3) */
+                || NEVER((sCost.plan.wsFlags & WHERE_NOT_FULLSCAN)!=0))
+            && (bestJ<0 || sCost.rCost<bestPlan.rCost      /* (4) */
+                || (sCost.rCost<=bestPlan.rCost && sCost.nRow<bestPlan.nRow))
         ){
           WHERETRACE(("... best so far with cost=%g and nRow=%g\n",
                       sCost.rCost, sCost.nRow));
@@ -97698,26 +99522,26 @@
 **                       defined, then do no error processing.
 */
 #define YYCODETYPE unsigned char
-#define YYNOCODE 254
+#define YYNOCODE 253
 #define YYACTIONTYPE unsigned short int
 #define YYWILDCARD 67
 #define sqlite3ParserTOKENTYPE Token
 typedef union {
   int yyinit;
   sqlite3ParserTOKENTYPE yy0;
-  Select* yy3;
-  ExprList* yy14;
-  SrcList* yy65;
-  struct LikeOp yy96;
-  Expr* yy132;
-  u8 yy186;
-  int yy328;
-  ExprSpan yy346;
-  struct TrigEvent yy378;
-  IdList* yy408;
-  struct {int value; int mask;} yy429;
-  TriggerStep* yy473;
-  struct LimitVal yy476;
+  int yy4;
+  struct TrigEvent yy90;
+  ExprSpan yy118;
+  TriggerStep* yy203;
+  u8 yy210;
+  struct {int value; int mask;} yy215;
+  SrcList* yy259;
+  struct LimitVal yy292;
+  Expr* yy314;
+  ExprList* yy322;
+  struct LikeOp yy342;
+  IdList* yy384;
+  Select* yy387;
 } YYMINORTYPE;
 #ifndef YYSTACKDEPTH
 #define YYSTACKDEPTH 100
@@ -97726,8 +99550,8 @@
 #define sqlite3ParserARG_PDECL ,Parse *pParse
 #define sqlite3ParserARG_FETCH Parse *pParse = yypParser->pParse
 #define sqlite3ParserARG_STORE yypParser->pParse = pParse
-#define YYNSTATE 631
-#define YYNRULE 330
+#define YYNSTATE 630
+#define YYNRULE 329
 #define YYFALLBACK 1
 #define YY_NO_ACTION      (YYNSTATE+YYNRULE+2)
 #define YY_ACCEPT_ACTION  (YYNSTATE+YYNRULE+1)
@@ -97797,472 +99621,473 @@
 **                     shifting non-terminals after a reduce.
 **  yy_default[]       Default action for each state.
 */
-#define YY_ACTTAB_COUNT (1550)
+#define YY_ACTTAB_COUNT (1557)
 static const YYACTIONTYPE yy_action[] = {
- /*     0 */   313,   49,  556,   46,  147,  172,  628,  598,   55,   55,
- /*    10 */    55,   55,  302,   53,   53,   53,   53,   52,   52,   51,
- /*    20 */    51,   51,   50,  238,  603,   66,  624,  623,  604,  598,
- /*    30 */   591,  585,   48,   53,   53,   53,   53,   52,   52,   51,
- /*    40 */    51,   51,   50,  238,   51,   51,   51,   50,  238,   56,
- /*    50 */    57,   47,  583,  582,  584,  584,   54,   54,   55,   55,
- /*    60 */    55,   55,  609,   53,   53,   53,   53,   52,   52,   51,
- /*    70 */    51,   51,   50,  238,  313,  598,  672,  330,  411,  217,
+ /*     0 */   313,  960,  186,  419,    2,  172,  627,  597,   55,   55,
+ /*    10 */    55,   55,   48,   53,   53,   53,   53,   52,   52,   51,
+ /*    20 */    51,   51,   50,  238,  302,  283,  623,  622,  516,  515,
+ /*    30 */   590,  584,   55,   55,   55,   55,  282,   53,   53,   53,
+ /*    40 */    53,   52,   52,   51,   51,   51,   50,  238,    6,   56,
+ /*    50 */    57,   47,  582,  581,  583,  583,   54,   54,   55,   55,
+ /*    60 */    55,   55,  608,   53,   53,   53,   53,   52,   52,   51,
+ /*    70 */    51,   51,   50,  238,  313,  597,  409,  330,  579,  579,
  /*    80 */    32,   53,   53,   53,   53,   52,   52,   51,   51,   51,
- /*    90 */    50,  238,  330,  414,  621,  620,  166,  598,  673,  382,
- /*   100 */   379,  378,  602,   73,  591,  585,  307,  424,  166,   58,
- /*   110 */   377,  382,  379,  378,  516,  515,  624,  623,  254,  200,
- /*   120 */   199,  198,  377,   56,   57,   47,  583,  582,  584,  584,
- /*   130 */    54,   54,   55,   55,   55,   55,  581,   53,   53,   53,
- /*   140 */    53,   52,   52,   51,   51,   51,   50,  238,  313,  270,
- /*   150 */   226,  422,  283,  133,  177,  139,  284,  385,  279,  384,
- /*   160 */   169,  197,  251,  282,  253,  226,  411,  275,  440,  167,
- /*   170 */   139,  284,  385,  279,  384,  169,  571,  236,  591,  585,
- /*   180 */   240,  414,  275,  622,  621,  620,  674,  437,  441,  442,
- /*   190 */   602,   88,  352,  266,  439,  268,  438,   56,   57,   47,
- /*   200 */   583,  582,  584,  584,   54,   54,   55,   55,   55,   55,
+ /*    90 */    50,  238,  330,  217,  620,  619,  166,  411,  624,  382,
+ /*   100 */   379,  378,    7,  491,  590,  584,  200,  199,  198,   58,
+ /*   110 */   377,  300,  414,  621,  481,   66,  623,  622,  621,  580,
+ /*   120 */   254,  601,   94,   56,   57,   47,  582,  581,  583,  583,
+ /*   130 */    54,   54,   55,   55,   55,   55,  671,   53,   53,   53,
+ /*   140 */    53,   52,   52,   51,   51,   51,   50,  238,  313,  532,
+ /*   150 */   226,  506,  507,  133,  177,  139,  284,  385,  279,  384,
+ /*   160 */   169,  197,  342,  398,  251,  226,  253,  275,  388,  167,
+ /*   170 */   139,  284,  385,  279,  384,  169,  570,  236,  590,  584,
+ /*   180 */   672,  240,  275,  157,  620,  619,  554,  437,   51,   51,
+ /*   190 */    51,   50,  238,  343,  439,  553,  438,   56,   57,   47,
+ /*   200 */   582,  581,  583,  583,   54,   54,   55,   55,   55,   55,
  /*   210 */   465,   53,   53,   53,   53,   52,   52,   51,   51,   51,
- /*   220 */    50,  238,  313,  471,   52,   52,   51,   51,   51,   50,
- /*   230 */   238,  234,  166,  491,  567,  382,  379,  378,    1,  440,
- /*   240 */   252,  176,  624,  623,  608,   67,  377,  513,  622,  443,
- /*   250 */   237,  577,  591,  585,  622,  172,  466,  598,  554,  441,
- /*   260 */   340,  409,  526,  580,  580,  349,  596,  553,  194,  482,
- /*   270 */   175,   56,   57,   47,  583,  582,  584,  584,   54,   54,
- /*   280 */    55,   55,   55,   55,  562,   53,   53,   53,   53,   52,
- /*   290 */    52,   51,   51,   51,   50,  238,  313,  594,  594,  594,
- /*   300 */   561,  578,  469,   65,  259,  351,  258,  411,  624,  623,
- /*   310 */   621,  620,  332,  576,  575,  240,  560,  568,  520,  411,
- /*   320 */   341,  237,  414,  624,  623,  598,  591,  585,  542,  519,
- /*   330 */   171,  602,   95,   68,  414,  624,  623,  624,  623,   38,
- /*   340 */   877,  506,  507,  602,   88,   56,   57,   47,  583,  582,
- /*   350 */   584,  584,   54,   54,   55,   55,   55,   55,  532,   53,
+ /*   220 */    50,  238,  313,  390,   52,   52,   51,   51,   51,   50,
+ /*   230 */   238,  391,  166,  491,  566,  382,  379,  378,  409,  440,
+ /*   240 */   579,  579,  252,  440,  607,   66,  377,  513,  621,   49,
+ /*   250 */    46,  147,  590,  584,  621,   16,  466,  189,  621,  441,
+ /*   260 */   442,  673,  526,  441,  340,  577,  595,   64,  194,  482,
+ /*   270 */   434,   56,   57,   47,  582,  581,  583,  583,   54,   54,
+ /*   280 */    55,   55,   55,   55,   30,   53,   53,   53,   53,   52,
+ /*   290 */    52,   51,   51,   51,   50,  238,  313,  593,  593,  593,
+ /*   300 */   387,  578,  606,  493,  259,  351,  258,  411,    1,  623,
+ /*   310 */   622,  496,  623,  622,   65,  240,  623,  622,  597,  443,
+ /*   320 */   237,  239,  414,  341,  237,  602,  590,  584,   18,  603,
+ /*   330 */   166,  601,   87,  382,  379,  378,   67,  623,  622,   38,
+ /*   340 */   623,  622,  176,  270,  377,   56,   57,   47,  582,  581,
+ /*   350 */   583,  583,   54,   54,   55,   55,   55,   55,  175,   53,
  /*   360 */    53,   53,   53,   52,   52,   51,   51,   51,   50,  238,
- /*   370 */   313,  411,  579,  398,  531,  237,  621,  620,  388,  625,
- /*   380 */   500,  206,  167,  396,  233,  312,  414,  387,  569,  492,
- /*   390 */   216,  621,  620,  566,  622,  602,   74,  533,  210,  491,
- /*   400 */   591,  585,  548,  621,  620,  621,  620,  300,  598,  466,
- /*   410 */   481,   67,  603,   35,  622,  601,  604,  547,    6,   56,
- /*   420 */    57,   47,  583,  582,  584,  584,   54,   54,   55,   55,
- /*   430 */    55,   55,  601,   53,   53,   53,   53,   52,   52,   51,
- /*   440 */    51,   51,   50,  238,  313,  411,  184,  409,  528,  580,
- /*   450 */   580,  551,  962,  186,  419,    2,  353,  259,  351,  258,
- /*   460 */   414,  409,  411,  580,  580,   44,  411,  544,  240,  602,
- /*   470 */    94,  190,    7,   62,  591,  585,  598,  414,  350,  607,
- /*   480 */   493,  414,  409,  317,  580,  580,  602,   95,  496,  565,
- /*   490 */   602,   80,  203,   56,   57,   47,  583,  582,  584,  584,
- /*   500 */    54,   54,   55,   55,   55,   55,  535,   53,   53,   53,
- /*   510 */    53,   52,   52,   51,   51,   51,   50,  238,  313,  202,
- /*   520 */   564,  293,  511,   49,  562,   46,  147,  411,  394,  183,
- /*   530 */   563,  549,  505,  549,  174,  409,  322,  580,  580,   39,
- /*   540 */   561,   37,  414,  624,  623,  192,  473,  383,  591,  585,
- /*   550 */   474,  602,   80,  601,  504,  544,  560,  364,  402,  210,
- /*   560 */   421,  952,  361,  952,  365,  201,  144,   56,   57,   47,
- /*   570 */   583,  582,  584,  584,   54,   54,   55,   55,   55,   55,
- /*   580 */   559,   53,   53,   53,   53,   52,   52,   51,   51,   51,
- /*   590 */    50,  238,  313,  601,  232,  264,  272,  321,  374,  484,
- /*   600 */   510,  146,  342,  146,  328,  425,  485,  407,  576,  575,
- /*   610 */   622,  621,  620,   49,  168,   46,  147,  353,  546,  491,
- /*   620 */   204,  240,  591,  585,  421,  951,  549,  951,  549,  168,
- /*   630 */   429,   67,  390,  343,  622,  434,  307,  423,  338,  360,
- /*   640 */   391,   56,   57,   47,  583,  582,  584,  584,   54,   54,
- /*   650 */    55,   55,   55,   55,  601,   53,   53,   53,   53,   52,
- /*   660 */    52,   51,   51,   51,   50,  238,  313,   34,  318,  425,
- /*   670 */   237,   21,  359,  273,  411,  167,  411,  276,  411,  540,
- /*   680 */   411,  422,   13,  318,  619,  618,  617,  622,  275,  414,
- /*   690 */   336,  414,  622,  414,  622,  414,  591,  585,  602,   69,
- /*   700 */   602,   97,  602,  100,  602,   98,  631,  629,  334,  475,
- /*   710 */   475,  367,  319,  148,  327,   56,   57,   47,  583,  582,
- /*   720 */   584,  584,   54,   54,   55,   55,   55,   55,  411,   53,
+ /*   370 */   313,  396,  233,  411,  531,  565,  317,  620,  619,   44,
+ /*   380 */   620,  619,  240,  206,  620,  619,  597,  266,  414,  268,
+ /*   390 */   409,  597,  579,  579,  352,  184,  505,  601,   73,  533,
+ /*   400 */   590,  584,  466,  548,  190,  620,  619,  576,  620,  619,
+ /*   410 */   547,  383,  551,   35,  332,  575,  574,  600,  504,   56,
+ /*   420 */    57,   47,  582,  581,  583,  583,   54,   54,   55,   55,
+ /*   430 */    55,   55,  567,   53,   53,   53,   53,   52,   52,   51,
+ /*   440 */    51,   51,   50,  238,  313,  411,  561,  561,  528,  364,
+ /*   450 */   259,  351,  258,  183,  361,  549,  524,  374,  411,  597,
+ /*   460 */   414,  240,  560,  560,  409,  604,  579,  579,  328,  601,
+ /*   470 */    93,  623,  622,  414,  590,  584,  237,  564,  559,  559,
+ /*   480 */   520,  402,  601,   87,  409,  210,  579,  579,  168,  421,
+ /*   490 */   950,  519,  950,   56,   57,   47,  582,  581,  583,  583,
+ /*   500 */    54,   54,   55,   55,   55,   55,  192,   53,   53,   53,
+ /*   510 */    53,   52,   52,   51,   51,   51,   50,  238,  313,  600,
+ /*   520 */   293,  563,  511,  234,  357,  146,  475,  475,  367,  411,
+ /*   530 */   562,  411,  358,  542,  425,  171,  411,  215,  144,  620,
+ /*   540 */   619,  544,  318,  353,  414,  203,  414,  275,  590,  584,
+ /*   550 */   549,  414,  174,  601,   94,  601,   79,  558,  471,   61,
+ /*   560 */   601,   79,  421,  949,  350,  949,   34,   56,   57,   47,
+ /*   570 */   582,  581,  583,  583,   54,   54,   55,   55,   55,   55,
+ /*   580 */   535,   53,   53,   53,   53,   52,   52,   51,   51,   51,
+ /*   590 */    50,  238,  313,  307,  424,  394,  272,   49,   46,  147,
+ /*   600 */   349,  322,    4,  411,  491,  312,  321,  425,  568,  492,
+ /*   610 */   216,  264,  407,  575,  574,  429,   66,  549,  414,  621,
+ /*   620 */   540,  602,  590,  584,   13,  603,  621,  601,   72,   12,
+ /*   630 */   618,  617,  616,  202,  210,  621,  546,  469,  422,  319,
+ /*   640 */   148,   56,   57,   47,  582,  581,  583,  583,   54,   54,
+ /*   650 */    55,   55,   55,   55,  338,   53,   53,   53,   53,   52,
+ /*   660 */    52,   51,   51,   51,   50,  238,  313,  600,  600,  411,
+ /*   670 */    39,   21,   37,  170,  237,  875,  411,  572,  572,  201,
+ /*   680 */   144,  473,  538,  331,  414,  474,  143,  146,  630,  628,
+ /*   690 */   334,  414,  353,  601,   68,  168,  590,  584,  132,  365,
+ /*   700 */   601,   96,  307,  423,  530,  336,   49,   46,  147,  568,
+ /*   710 */   406,  216,  549,  360,  529,   56,   57,   47,  582,  581,
+ /*   720 */   583,  583,   54,   54,   55,   55,   55,   55,  411,   53,
  /*   730 */    53,   53,   53,   52,   52,   51,   51,   51,   50,  238,
- /*   740 */   313,  411,  331,  414,  411,   49,  276,   46,  147,  569,
- /*   750 */   406,  216,  602,  106,  573,  573,  414,  354,  524,  414,
- /*   760 */   411,  622,  411,  224,    4,  602,  104,  605,  602,  108,
- /*   770 */   591,  585,  622,   20,  375,  414,  167,  414,  215,  144,
- /*   780 */   470,  239,  167,  225,  602,  109,  602,  134,   18,   56,
- /*   790 */    57,   47,  583,  582,  584,  584,   54,   54,   55,   55,
+ /*   740 */   313,  411,  605,  414,  484,  510,  172,  422,  597,  318,
+ /*   750 */   496,  485,  601,   99,  411,  142,  414,  411,  231,  411,
+ /*   760 */   540,  411,  359,  629,    2,  601,   97,  426,  308,  414,
+ /*   770 */   590,  584,  414,   20,  414,  621,  414,  621,  601,  106,
+ /*   780 */   503,  601,  105,  601,  108,  601,  109,  204,   28,   56,
+ /*   790 */    57,   47,  582,  581,  583,  583,   54,   54,   55,   55,
  /*   800 */    55,   55,  411,   53,   53,   53,   53,   52,   52,   51,
- /*   810 */    51,   51,   50,  238,  313,  411,  276,  414,   12,  459,
- /*   820 */   276,  171,  411,   16,  223,  189,  602,  135,  354,  170,
- /*   830 */   414,  622,  630,    2,  411,  622,  540,  414,  143,  602,
- /*   840 */    61,  359,  132,  622,  591,  585,  602,  105,  458,  414,
- /*   850 */    23,  622,  446,  326,   23,  538,  622,  325,  602,  103,
- /*   860 */   427,  530,  309,   56,   57,   47,  583,  582,  584,  584,
+ /*   810 */    51,   51,   50,  238,  313,  411,  597,  414,  411,  276,
+ /*   820 */   214,  600,  411,  366,  213,  381,  601,  134,  274,  500,
+ /*   830 */   414,  167,  130,  414,  621,  411,  354,  414,  376,  601,
+ /*   840 */   135,  129,  601,  100,  590,  584,  601,  104,  522,  521,
+ /*   850 */   414,  621,  224,  273,  600,  167,  327,  282,  600,  601,
+ /*   860 */   103,  468,  521,   56,   57,   47,  582,  581,  583,  583,
  /*   870 */    54,   54,   55,   55,   55,   55,  411,   53,   53,   53,
  /*   880 */    53,   52,   52,   51,   51,   51,   50,  238,  313,  411,
- /*   890 */   264,  414,  411,  276,  359,  219,  157,  214,  357,  366,
- /*   900 */   602,   96,  522,  521,  414,  622,  358,  414,  622,  622,
- /*   910 */   411,  613,  612,  602,  102,  142,  602,   77,  591,  585,
- /*   920 */   529,  540,  231,  426,  308,  414,  622,  622,  468,  521,
- /*   930 */   324,  601,  257,  263,  602,   99,  622,   56,   45,   47,
- /*   940 */   583,  582,  584,  584,   54,   54,   55,   55,   55,   55,
+ /*   890 */    27,  414,  411,  375,  276,  167,  359,  544,   50,  238,
+ /*   900 */   601,   95,  128,  223,  414,  411,  165,  414,  411,  621,
+ /*   910 */   411,  621,  612,  601,  102,  372,  601,   76,  590,  584,
+ /*   920 */   414,  570,  236,  414,  470,  414,  167,  621,  188,  601,
+ /*   930 */    98,  225,  601,  138,  601,  137,  232,   56,   45,   47,
+ /*   940 */   582,  581,  583,  583,   54,   54,   55,   55,   55,   55,
  /*   950 */   411,   53,   53,   53,   53,   52,   52,   51,   51,   51,
- /*   960 */    50,  238,  313,  264,  264,  414,  411,  213,  209,  544,
- /*   970 */   544,  207,  611,   28,  602,  138,   50,  238,  622,  622,
- /*   980 */   381,  414,  503,  140,  323,  222,  274,  622,  590,  589,
- /*   990 */   602,  137,  591,  585,  629,  334,  606,   30,  622,  571,
- /*  1000 */   236,  601,  601,  130,  496,  601,  453,  451,  288,  286,
- /*  1010 */   587,  586,   57,   47,  583,  582,  584,  584,   54,   54,
+ /*   960 */    50,  238,  313,  276,  276,  414,  411,  276,  544,  459,
+ /*   970 */   359,  171,  209,  479,  601,  136,  628,  334,  621,  621,
+ /*   980 */   125,  414,  621,  368,  411,  621,  257,  540,  589,  588,
+ /*   990 */   601,   75,  590,  584,  458,  446,   23,   23,  124,  414,
+ /*  1000 */   326,  325,  621,  427,  324,  309,  600,  288,  601,   92,
+ /*  1010 */   586,  585,   57,   47,  582,  581,  583,  583,   54,   54,
  /*  1020 */    55,   55,   55,   55,  411,   53,   53,   53,   53,   52,
- /*  1030 */    52,   51,   51,   51,   50,  238,  313,  588,  411,  414,
- /*  1040 */   411,  264,  410,  129,  595,  400,   27,  376,  602,  136,
- /*  1050 */   128,  165,  479,  414,  282,  414,  622,  622,  411,  622,
- /*  1060 */   622,  411,  602,   76,  602,   93,  591,  585,  188,  372,
- /*  1070 */   368,  125,  476,  414,  261,  160,  414,  171,  124,  472,
- /*  1080 */   123,   15,  602,   92,  450,  602,   75,   47,  583,  582,
- /*  1090 */   584,  584,   54,   54,   55,   55,   55,   55,  464,   53,
+ /*  1030 */    52,   51,   51,   51,   50,  238,  313,  587,  411,  414,
+ /*  1040 */   411,  207,  611,  476,  171,  472,  160,  123,  601,   91,
+ /*  1050 */   323,  261,   15,  414,  464,  414,  411,  621,  411,  354,
+ /*  1060 */   222,  411,  601,   74,  601,   90,  590,  584,  159,  264,
+ /*  1070 */   158,  414,  461,  414,  621,  600,  414,  121,  120,   25,
+ /*  1080 */   601,   89,  601,  101,  621,  601,   88,   47,  582,  581,
+ /*  1090 */   583,  583,   54,   54,   55,   55,   55,   55,  544,   53,
  /*  1100 */    53,   53,   53,   52,   52,   51,   51,   51,   50,  238,
- /*  1110 */    43,  405,  264,    3,  558,  264,  545,  415,  623,  159,
- /*  1120 */   541,  158,  539,  278,   25,  461,  121,  622,  408,  622,
- /*  1130 */   622,  622,   24,   43,  405,  622,    3,  622,  622,  120,
- /*  1140 */   415,  623,   11,  456,  411,  156,  452,  403,  509,  277,
- /*  1150 */   118,  408,  489,  113,  205,  449,  271,  567,  221,  414,
- /*  1160 */   269,  267,  155,  622,  622,  111,  411,  622,  602,   95,
- /*  1170 */   403,  622,  411,  110,   10,  622,  622,   40,   41,  534,
- /*  1180 */   567,  414,   64,  264,   42,  413,  412,  414,  601,  596,
- /*  1190 */   602,   91,  445,  436,  150,  435,  602,   90,  622,  265,
- /*  1200 */    40,   41,  337,  242,  411,  191,  333,   42,  413,  412,
- /*  1210 */   398,  420,  596,  316,  622,  399,  260,  107,  230,  414,
- /*  1220 */   594,  594,  594,  593,  592,   14,  220,  411,  602,  101,
- /*  1230 */   240,  622,   43,  405,  362,    3,  149,  315,  626,  415,
- /*  1240 */   623,  127,  414,  594,  594,  594,  593,  592,   14,  622,
- /*  1250 */   408,  602,   89,  411,  181,   33,  405,  463,    3,  411,
- /*  1260 */   264,  462,  415,  623,  616,  615,  614,  355,  414,  403,
- /*  1270 */   417,  416,  622,  408,  414,  622,  622,  602,   87,  567,
- /*  1280 */   418,  627,  622,  602,   86,    8,  241,  180,  126,  255,
- /*  1290 */   600,  178,  403,  240,  208,  455,  395,  294,  444,   40,
- /*  1300 */    41,  297,  567,  248,  622,  296,   42,  413,  412,  247,
- /*  1310 */   622,  596,  244,  622,   30,   60,   31,  243,  430,  624,
- /*  1320 */   623,  292,   40,   41,  622,  295,  145,  622,  601,   42,
- /*  1330 */   413,  412,  622,  622,  596,  393,  622,  397,  599,   59,
- /*  1340 */   235,  622,  594,  594,  594,  593,  592,   14,  218,  291,
- /*  1350 */   622,   36,  344,  305,  304,  303,  179,  301,  411,  567,
- /*  1360 */   454,  557,  173,  185,  622,  594,  594,  594,  593,  592,
- /*  1370 */    14,  411,   29,  414,  151,  289,  246,  523,  411,  196,
- /*  1380 */   195,  335,  602,   85,  411,  245,  414,  526,  392,  543,
- /*  1390 */   411,  596,  287,  414,  285,  602,   72,  537,  153,  414,
- /*  1400 */   466,  411,  602,   71,  154,  414,  411,  152,  602,   84,
- /*  1410 */   386,  536,  329,  411,  602,   83,  414,  518,  280,  411,
- /*  1420 */   513,  414,  594,  594,  594,  602,   82,  517,  414,  311,
- /*  1430 */   602,   81,  411,  514,  414,  512,  131,  602,   70,  229,
- /*  1440 */   228,  227,  494,  602,   17,  411,  488,  414,  259,  346,
- /*  1450 */   249,  389,  487,  486,  314,  164,  602,   79,  310,  240,
- /*  1460 */   414,  373,  480,  163,  262,  371,  414,  162,  369,  602,
- /*  1470 */    78,  212,  478,   26,  477,  602,    9,  161,  467,  363,
- /*  1480 */   141,  122,  339,  187,  119,  457,  348,  347,  117,  116,
- /*  1490 */   115,  112,  114,  448,  182,   22,  320,  433,  432,  431,
- /*  1500 */    19,  428,  610,  597,  574,  193,  572,   63,  298,  404,
- /*  1510 */   555,  552,  290,  281,  510,  460,  498,  499,  495,  447,
- /*  1520 */   356,  497,  256,  380,  306,  570,    5,  250,  345,  238,
- /*  1530 */   299,  550,  527,  490,  508,  525,  502,  401,  501,  963,
- /*  1540 */   211,  963,  483,  963,  963,  963,  963,  963,  963,  370,
+ /*  1110 */    43,  405,  263,    3,  610,  264,  140,  415,  622,   24,
+ /*  1120 */   410,   11,  456,  594,  118,  155,  219,  452,  408,  621,
+ /*  1130 */   621,  621,  156,   43,  405,  621,    3,  286,  621,  113,
+ /*  1140 */   415,  622,  111,  445,  411,  400,  557,  403,  545,   10,
+ /*  1150 */   411,  408,  264,  110,  205,  436,  541,  566,  453,  414,
+ /*  1160 */   621,  621,   63,  621,  435,  414,  411,  621,  601,   94,
+ /*  1170 */   403,  621,  411,  337,  601,   86,  150,   40,   41,  534,
+ /*  1180 */   566,  414,  242,  264,   42,  413,  412,  414,  600,  595,
+ /*  1190 */   601,   85,  191,  333,  107,  451,  601,   84,  621,  539,
+ /*  1200 */    40,   41,  420,  230,  411,  149,  316,   42,  413,  412,
+ /*  1210 */   398,  127,  595,  315,  621,  399,  278,  625,  181,  414,
+ /*  1220 */   593,  593,  593,  592,  591,   14,  450,  411,  601,   71,
+ /*  1230 */   240,  621,   43,  405,  264,    3,  615,  180,  264,  415,
+ /*  1240 */   622,  614,  414,  593,  593,  593,  592,  591,   14,  621,
+ /*  1250 */   408,  601,   70,  621,  417,   33,  405,  613,    3,  411,
+ /*  1260 */   264,  411,  415,  622,  418,  626,  178,  509,    8,  403,
+ /*  1270 */   241,  416,  126,  408,  414,  621,  414,  449,  208,  566,
+ /*  1280 */   240,  221,  621,  601,   83,  601,   82,  599,  297,  277,
+ /*  1290 */   296,   30,  403,   31,  395,  264,  295,  397,  489,   40,
+ /*  1300 */    41,  411,  566,  220,  621,  294,   42,  413,  412,  271,
+ /*  1310 */   621,  595,  600,  621,   59,   60,  414,  269,  267,  623,
+ /*  1320 */   622,   36,   40,   41,  621,  601,   81,  598,  235,   42,
+ /*  1330 */   413,  412,  621,  621,  595,  265,  344,  411,  248,  556,
+ /*  1340 */   173,  185,  593,  593,  593,  592,  591,   14,  218,   29,
+ /*  1350 */   621,  543,  414,  305,  304,  303,  179,  301,  411,  566,
+ /*  1360 */   454,  601,   80,  289,  335,  593,  593,  593,  592,  591,
+ /*  1370 */    14,  411,  287,  414,  151,  392,  246,  260,  411,  196,
+ /*  1380 */   195,  523,  601,   69,  411,  245,  414,  526,  537,  285,
+ /*  1390 */   389,  595,  621,  414,  536,  601,   17,  362,  153,  414,
+ /*  1400 */   466,  463,  601,   78,  154,  414,  462,  152,  601,   77,
+ /*  1410 */   355,  255,  621,  455,  601,    9,  621,  386,  444,  517,
+ /*  1420 */   247,  621,  593,  593,  593,  621,  621,  244,  621,  243,
+ /*  1430 */   430,  518,  292,  621,  329,  621,  145,  393,  280,  513,
+ /*  1440 */   291,  131,  621,  514,  621,  621,  311,  621,  259,  346,
+ /*  1450 */   249,  621,  621,  229,  314,  621,  228,  512,  227,  240,
+ /*  1460 */   494,  488,  310,  164,  487,  486,  373,  480,  163,  262,
+ /*  1470 */   369,  371,  162,   26,  212,  478,  477,  161,  141,  363,
+ /*  1480 */   467,  122,  339,  187,  119,  348,  347,  117,  116,  115,
+ /*  1490 */   114,  112,  182,  457,  320,   22,  433,  432,  448,   19,
+ /*  1500 */   609,  431,  428,   62,  193,  596,  573,  298,  555,  552,
+ /*  1510 */   571,  404,  290,  380,  498,  510,  495,  306,  281,  499,
+ /*  1520 */   250,    5,  497,  460,  345,  447,  569,  550,  238,  299,
+ /*  1530 */   527,  525,  508,  961,  502,  501,  961,  401,  961,  211,
+ /*  1540 */   490,  356,  256,  961,  483,  961,  961,  961,  961,  961,
+ /*  1550 */   961,  961,  961,  961,  961,  961,  370,
 };
 static const YYCODETYPE yy_lookahead[] = {
- /*     0 */    19,  222,  223,  224,  225,   24,    1,   26,   77,   78,
- /*    10 */    79,   80,   15,   82,   83,   84,   85,   86,   87,   88,
- /*    20 */    89,   90,   91,   92,  113,   22,   26,   27,  117,   26,
- /*    30 */    49,   50,   81,   82,   83,   84,   85,   86,   87,   88,
- /*    40 */    89,   90,   91,   92,   88,   89,   90,   91,   92,   68,
+ /*     0 */    19,  142,  143,  144,  145,   24,    1,   26,   77,   78,
+ /*    10 */    79,   80,   81,   82,   83,   84,   85,   86,   87,   88,
+ /*    20 */    89,   90,   91,   92,   15,   98,   26,   27,    7,    8,
+ /*    30 */    49,   50,   77,   78,   79,   80,  109,   82,   83,   84,
+ /*    40 */    85,   86,   87,   88,   89,   90,   91,   92,   22,   68,
  /*    50 */    69,   70,   71,   72,   73,   74,   75,   76,   77,   78,
  /*    60 */    79,   80,   23,   82,   83,   84,   85,   86,   87,   88,
- /*    70 */    89,   90,   91,   92,   19,   94,  118,   19,  150,   22,
+ /*    70 */    89,   90,   91,   92,   19,   94,  112,   19,  114,  115,
  /*    80 */    25,   82,   83,   84,   85,   86,   87,   88,   89,   90,
- /*    90 */    91,   92,   19,  165,   94,   95,   96,   94,  118,   99,
- /*   100 */   100,  101,  174,  175,   49,   50,   22,   23,   96,   54,
- /*   110 */   110,   99,  100,  101,    7,    8,   26,   27,   16,  105,
- /*   120 */   106,  107,  110,   68,   69,   70,   71,   72,   73,   74,
- /*   130 */    75,   76,   77,   78,   79,   80,  113,   82,   83,   84,
- /*   140 */    85,   86,   87,   88,   89,   90,   91,   92,   19,   16,
- /*   150 */    92,   67,   98,   24,   96,   97,   98,   99,  100,  101,
- /*   160 */   102,   25,   60,  109,   62,   92,  150,  109,  150,   25,
+ /*    90 */    91,   92,   19,   22,   94,   95,   96,  150,  150,   99,
+ /*   100 */   100,  101,   76,  150,   49,   50,  105,  106,  107,   54,
+ /*   110 */   110,  158,  165,  165,  161,  162,   26,   27,  165,  113,
+ /*   120 */    16,  174,  175,   68,   69,   70,   71,   72,   73,   74,
+ /*   130 */    75,   76,   77,   78,   79,   80,  118,   82,   83,   84,
+ /*   140 */    85,   86,   87,   88,   89,   90,   91,   92,   19,   23,
+ /*   150 */    92,   97,   98,   24,   96,   97,   98,   99,  100,  101,
+ /*   160 */   102,   25,   97,  216,   60,   92,   62,  109,  221,   25,
  /*   170 */    97,   98,   99,  100,  101,  102,   86,   87,   49,   50,
- /*   180 */   116,  165,  109,  165,   94,   95,  118,   97,  170,  171,
- /*   190 */   174,  175,  128,   60,  104,   62,  106,   68,   69,   70,
+ /*   180 */   118,  116,  109,   25,   94,   95,   32,   97,   88,   89,
+ /*   190 */    90,   91,   92,  128,  104,   41,  106,   68,   69,   70,
  /*   200 */    71,   72,   73,   74,   75,   76,   77,   78,   79,   80,
  /*   210 */    11,   82,   83,   84,   85,   86,   87,   88,   89,   90,
- /*   220 */    91,   92,   19,   21,   86,   87,   88,   89,   90,   91,
- /*   230 */    92,  215,   96,  150,   66,   99,  100,  101,   22,  150,
- /*   240 */   138,  118,   26,   27,  161,  162,  110,  103,  165,  231,
- /*   250 */   232,   23,   49,   50,  165,   24,   57,   26,   32,  170,
- /*   260 */   171,  112,   94,  114,  115,   63,   98,   41,  185,  186,
- /*   270 */   118,   68,   69,   70,   71,   72,   73,   74,   75,   76,
- /*   280 */    77,   78,   79,   80,   12,   82,   83,   84,   85,   86,
+ /*   220 */    91,   92,   19,   19,   86,   87,   88,   89,   90,   91,
+ /*   230 */    92,   27,   96,  150,   66,   99,  100,  101,  112,  150,
+ /*   240 */   114,  115,  138,  150,  161,  162,  110,  103,  165,  222,
+ /*   250 */   223,  224,   49,   50,  165,   22,   57,   24,  165,  170,
+ /*   260 */   171,  118,   94,  170,  171,   23,   98,   25,  185,  186,
+ /*   270 */   243,   68,   69,   70,   71,   72,   73,   74,   75,   76,
+ /*   280 */    77,   78,   79,   80,  126,   82,   83,   84,   85,   86,
  /*   290 */    87,   88,   89,   90,   91,   92,   19,  129,  130,  131,
- /*   300 */    28,   23,  100,   25,  105,  106,  107,  150,   26,   27,
- /*   310 */    94,   95,  169,  170,  171,  116,   44,   23,   46,  150,
- /*   320 */   231,  232,  165,   26,   27,   94,   49,   50,   23,   57,
- /*   330 */    25,  174,  175,   22,  165,   26,   27,   26,   27,  136,
- /*   340 */   138,   97,   98,  174,  175,   68,   69,   70,   71,   72,
- /*   350 */    73,   74,   75,   76,   77,   78,   79,   80,   23,   82,
+ /*   300 */    88,   23,  172,  173,  105,  106,  107,  150,   22,   26,
+ /*   310 */    27,  181,   26,   27,   22,  116,   26,   27,   26,  230,
+ /*   320 */   231,  197,  165,  230,  231,  113,   49,   50,  204,  117,
+ /*   330 */    96,  174,  175,   99,  100,  101,   22,   26,   27,  136,
+ /*   340 */    26,   27,  118,   16,  110,   68,   69,   70,   71,   72,
+ /*   350 */    73,   74,   75,   76,   77,   78,   79,   80,  118,   82,
  /*   360 */    83,   84,   85,   86,   87,   88,   89,   90,   91,   92,
- /*   370 */    19,  150,   23,  216,   23,  232,   94,   95,  221,  150,
- /*   380 */    23,  160,   25,  214,  215,  163,  165,   88,  166,  167,
- /*   390 */   168,   94,   95,   23,  165,  174,  175,   88,  160,  150,
- /*   400 */    49,   50,  120,   94,   95,   94,   95,  158,   26,   57,
- /*   410 */   161,  162,  113,  136,  165,  194,  117,  120,   22,   68,
+ /*   370 */    19,  214,  215,  150,   23,   23,  155,   94,   95,   22,
+ /*   380 */    94,   95,  116,  160,   94,   95,   94,   60,  165,   62,
+ /*   390 */   112,   26,  114,  115,  128,   23,   36,  174,  175,   88,
+ /*   400 */    49,   50,   57,  120,   22,   94,   95,   23,   94,   95,
+ /*   410 */   120,   51,   25,  136,  169,  170,  171,  194,   58,   68,
  /*   420 */    69,   70,   71,   72,   73,   74,   75,   76,   77,   78,
- /*   430 */    79,   80,  194,   82,   83,   84,   85,   86,   87,   88,
- /*   440 */    89,   90,   91,   92,   19,  150,   23,  112,   23,  114,
- /*   450 */   115,   25,  142,  143,  144,  145,  218,  105,  106,  107,
- /*   460 */   165,  112,  150,  114,  115,   22,  150,  166,  116,  174,
- /*   470 */   175,   22,   76,  235,   49,   50,   94,  165,  240,  172,
- /*   480 */   173,  165,  112,  155,  114,  115,  174,  175,  181,   11,
- /*   490 */   174,  175,   22,   68,   69,   70,   71,   72,   73,   74,
- /*   500 */    75,   76,   77,   78,   79,   80,  205,   82,   83,   84,
- /*   510 */    85,   86,   87,   88,   89,   90,   91,   92,   19,  160,
- /*   520 */    23,  226,   23,  222,   12,  224,  225,  150,  216,   23,
- /*   530 */    23,   25,   36,   25,   25,  112,  220,  114,  115,  135,
- /*   540 */    28,  137,  165,   26,   27,  119,   30,   51,   49,   50,
- /*   550 */    34,  174,  175,  194,   58,  166,   44,  229,   46,  160,
- /*   560 */    22,   23,  234,   25,   48,  206,  207,   68,   69,   70,
+ /*   430 */    79,   80,   23,   82,   83,   84,   85,   86,   87,   88,
+ /*   440 */    89,   90,   91,   92,   19,  150,   12,   12,   23,  228,
+ /*   450 */   105,  106,  107,   23,  233,   25,  165,   19,  150,   94,
+ /*   460 */   165,  116,   28,   28,  112,  174,  114,  115,  108,  174,
+ /*   470 */   175,   26,   27,  165,   49,   50,  231,   11,   44,   44,
+ /*   480 */    46,   46,  174,  175,  112,  160,  114,  115,   50,   22,
+ /*   490 */    23,   57,   25,   68,   69,   70,   71,   72,   73,   74,
+ /*   500 */    75,   76,   77,   78,   79,   80,  119,   82,   83,   84,
+ /*   510 */    85,   86,   87,   88,   89,   90,   91,   92,   19,  194,
+ /*   520 */   225,   23,   23,  215,   19,   95,  105,  106,  107,  150,
+ /*   530 */    23,  150,   27,   23,   67,   25,  150,  206,  207,   94,
+ /*   540 */    95,  166,  104,  218,  165,   22,  165,  109,   49,   50,
+ /*   550 */   120,  165,   25,  174,  175,  174,  175,   23,   21,  234,
+ /*   560 */   174,  175,   22,   23,  239,   25,   25,   68,   69,   70,
  /*   570 */    71,   72,   73,   74,   75,   76,   77,   78,   79,   80,
- /*   580 */    23,   82,   83,   84,   85,   86,   87,   88,   89,   90,
- /*   590 */    91,   92,   19,  194,  205,  150,   23,  220,   19,  181,
- /*   600 */   182,   95,   97,   95,  108,   67,  188,  169,  170,  171,
- /*   610 */   165,   94,   95,  222,   50,  224,  225,  218,  120,  150,
- /*   620 */   160,  116,   49,   50,   22,   23,  120,   25,  120,   50,
- /*   630 */   161,  162,   19,  128,  165,  244,   22,   23,  193,  240,
- /*   640 */    27,   68,   69,   70,   71,   72,   73,   74,   75,   76,
- /*   650 */    77,   78,   79,   80,  194,   82,   83,   84,   85,   86,
- /*   660 */    87,   88,   89,   90,   91,   92,   19,   25,  104,   67,
- /*   670 */   232,   24,  150,   23,  150,   25,  150,  150,  150,  150,
- /*   680 */   150,   67,   25,  104,    7,    8,    9,  165,  109,  165,
- /*   690 */   245,  165,  165,  165,  165,  165,   49,   50,  174,  175,
- /*   700 */   174,  175,  174,  175,  174,  175,    0,    1,    2,  105,
- /*   710 */   106,  107,  248,  249,  187,   68,   69,   70,   71,   72,
+ /*   580 */   205,   82,   83,   84,   85,   86,   87,   88,   89,   90,
+ /*   590 */    91,   92,   19,   22,   23,  216,   23,  222,  223,  224,
+ /*   600 */    63,  220,   35,  150,  150,  163,  220,   67,  166,  167,
+ /*   610 */   168,  150,  169,  170,  171,  161,  162,   25,  165,  165,
+ /*   620 */   150,  113,   49,   50,   25,  117,  165,  174,  175,   35,
+ /*   630 */     7,    8,    9,  160,  160,  165,  120,  100,   67,  247,
+ /*   640 */   248,   68,   69,   70,   71,   72,   73,   74,   75,   76,
+ /*   650 */    77,   78,   79,   80,  193,   82,   83,   84,   85,   86,
+ /*   660 */    87,   88,   89,   90,   91,   92,   19,  194,  194,  150,
+ /*   670 */   135,   24,  137,   35,  231,  138,  150,  129,  130,  206,
+ /*   680 */   207,   30,   27,  213,  165,   34,  118,   95,    0,    1,
+ /*   690 */     2,  165,  218,  174,  175,   50,   49,   50,   22,   48,
+ /*   700 */   174,  175,   22,   23,   23,  244,  222,  223,  224,  166,
+ /*   710 */   167,  168,  120,  239,   23,   68,   69,   70,   71,   72,
  /*   720 */    73,   74,   75,   76,   77,   78,   79,   80,  150,   82,
  /*   730 */    83,   84,   85,   86,   87,   88,   89,   90,   91,   92,
- /*   740 */    19,  150,  213,  165,  150,  222,  150,  224,  225,  166,
- /*   750 */   167,  168,  174,  175,  129,  130,  165,  150,  165,  165,
- /*   760 */   150,  165,  150,  241,   35,  174,  175,  174,  174,  175,
- /*   770 */    49,   50,  165,   52,   23,  165,   25,  165,  206,  207,
- /*   780 */    23,  197,   25,  187,  174,  175,  174,  175,  204,   68,
+ /*   740 */    19,  150,  173,  165,  181,  182,   24,   67,   26,  104,
+ /*   750 */   181,  188,  174,  175,  150,   39,  165,  150,   52,  150,
+ /*   760 */   150,  150,  150,  144,  145,  174,  175,  249,  250,  165,
+ /*   770 */    49,   50,  165,   52,  165,  165,  165,  165,  174,  175,
+ /*   780 */    29,  174,  175,  174,  175,  174,  175,  160,   22,   68,
  /*   790 */    69,   70,   71,   72,   73,   74,   75,   76,   77,   78,
  /*   800 */    79,   80,  150,   82,   83,   84,   85,   86,   87,   88,
- /*   810 */    89,   90,   91,   92,   19,  150,  150,  165,   35,   23,
- /*   820 */   150,   25,  150,   22,  217,   24,  174,  175,  150,   35,
- /*   830 */   165,  165,  144,  145,  150,  165,  150,  165,  118,  174,
- /*   840 */   175,  150,   22,  165,   49,   50,  174,  175,   23,  165,
- /*   850 */    25,  165,   23,  187,   25,   27,  165,  187,  174,  175,
- /*   860 */    23,   23,   25,   68,   69,   70,   71,   72,   73,   74,
+ /*   810 */    89,   90,   91,   92,   19,  150,   94,  165,  150,  150,
+ /*   820 */   160,  194,  150,  213,  160,   52,  174,  175,   23,   23,
+ /*   830 */   165,   25,   22,  165,  165,  150,  150,  165,   52,  174,
+ /*   840 */   175,   22,  174,  175,   49,   50,  174,  175,  190,  191,
+ /*   850 */   165,  165,  240,   23,  194,   25,  187,  109,  194,  174,
+ /*   860 */   175,  190,  191,   68,   69,   70,   71,   72,   73,   74,
  /*   870 */    75,   76,   77,   78,   79,   80,  150,   82,   83,   84,
  /*   880 */    85,   86,   87,   88,   89,   90,   91,   92,   19,  150,
- /*   890 */   150,  165,  150,  150,  150,  217,   25,  160,   19,  213,
- /*   900 */   174,  175,  190,  191,  165,  165,   27,  165,  165,  165,
- /*   910 */   150,  150,  150,  174,  175,   39,  174,  175,   49,   50,
- /*   920 */    23,  150,   52,  250,  251,  165,  165,  165,  190,  191,
- /*   930 */   187,  194,  241,  193,  174,  175,  165,   68,   69,   70,
+ /*   890 */    22,  165,  150,   23,  150,   25,  150,  166,   91,   92,
+ /*   900 */   174,  175,   22,  217,  165,  150,  102,  165,  150,  165,
+ /*   910 */   150,  165,  150,  174,  175,   19,  174,  175,   49,   50,
+ /*   920 */   165,   86,   87,  165,   23,  165,   25,  165,   24,  174,
+ /*   930 */   175,  187,  174,  175,  174,  175,  205,   68,   69,   70,
  /*   940 */    71,   72,   73,   74,   75,   76,   77,   78,   79,   80,
  /*   950 */   150,   82,   83,   84,   85,   86,   87,   88,   89,   90,
- /*   960 */    91,   92,   19,  150,  150,  165,  150,  160,  160,  166,
- /*   970 */   166,  160,  150,   22,  174,  175,   91,   92,  165,  165,
- /*   980 */    52,  165,   29,  150,  213,  241,   23,  165,   49,   50,
- /*   990 */   174,  175,   49,   50,    1,    2,  173,  126,  165,   86,
- /*  1000 */    87,  194,  194,   22,  181,  194,  193,  193,  205,  205,
+ /*   960 */    91,   92,   19,  150,  150,  165,  150,  150,  166,   23,
+ /*   970 */   150,   25,  160,   20,  174,  175,    1,    2,  165,  165,
+ /*   980 */   104,  165,  165,   43,  150,  165,  240,  150,   49,   50,
+ /*   990 */   174,  175,   49,   50,   23,   23,   25,   25,   53,  165,
+ /*  1000 */   187,  187,  165,   23,  187,   25,  194,  205,  174,  175,
  /*  1010 */    71,   72,   69,   70,   71,   72,   73,   74,   75,   76,
  /*  1020 */    77,   78,   79,   80,  150,   82,   83,   84,   85,   86,
  /*  1030 */    87,   88,   89,   90,   91,   92,   19,   98,  150,  165,
- /*  1040 */   150,  150,  150,   22,  150,  150,   22,   52,  174,  175,
- /*  1050 */    22,  102,   20,  165,  109,  165,  165,  165,  150,  165,
- /*  1060 */   165,  150,  174,  175,  174,  175,   49,   50,   24,   19,
- /*  1070 */    43,  104,   59,  165,  138,  104,  165,   25,   53,   53,
- /*  1080 */    22,    5,  174,  175,  193,  174,  175,   70,   71,   72,
- /*  1090 */    73,   74,   75,   76,   77,   78,   79,   80,    1,   82,
+ /*  1040 */   150,  160,  150,   59,   25,   53,  104,   22,  174,  175,
+ /*  1050 */   213,  138,    5,  165,    1,  165,  150,  165,  150,  150,
+ /*  1060 */   240,  150,  174,  175,  174,  175,   49,   50,  118,  150,
+ /*  1070 */    35,  165,   27,  165,  165,  194,  165,  108,  127,   76,
+ /*  1080 */   174,  175,  174,  175,  165,  174,  175,   70,   71,   72,
+ /*  1090 */    73,   74,   75,   76,   77,   78,   79,   80,  166,   82,
  /*  1100 */    83,   84,   85,   86,   87,   88,   89,   90,   91,   92,
- /*  1110 */    19,   20,  150,   22,  150,  150,  150,   26,   27,  118,
- /*  1120 */   150,   35,  150,  150,   76,   27,  108,  165,   37,  165,
- /*  1130 */   165,  165,   76,   19,   20,  165,   22,  165,  165,  127,
- /*  1140 */    26,   27,   22,    1,  150,   16,   20,   56,  150,  150,
- /*  1150 */   119,   37,  150,  119,  160,  193,  150,   66,  193,  165,
- /*  1160 */   150,  150,  121,  165,  165,  108,  150,  165,  174,  175,
- /*  1170 */    56,  165,  150,  127,   22,  165,  165,   86,   87,   88,
- /*  1180 */    66,  165,   16,  150,   93,   94,   95,  165,  194,   98,
- /*  1190 */   174,  175,  128,   23,   15,   23,  174,  175,  165,  150,
- /*  1200 */    86,   87,   65,  140,  150,   22,    3,   93,   94,   95,
- /*  1210 */   216,    4,   98,  252,  165,  221,  150,  164,  180,  165,
+ /*  1110 */    19,   20,  193,   22,  150,  150,  150,   26,   27,   76,
+ /*  1120 */   150,   22,    1,  150,  119,  121,  217,   20,   37,  165,
+ /*  1130 */   165,  165,   16,   19,   20,  165,   22,  205,  165,  119,
+ /*  1140 */    26,   27,  108,  128,  150,  150,  150,   56,  150,   22,
+ /*  1150 */   150,   37,  150,  127,  160,   23,  150,   66,  193,  165,
+ /*  1160 */   165,  165,   16,  165,   23,  165,  150,  165,  174,  175,
+ /*  1170 */    56,  165,  150,   65,  174,  175,   15,   86,   87,   88,
+ /*  1180 */    66,  165,  140,  150,   93,   94,   95,  165,  194,   98,
+ /*  1190 */   174,  175,   22,    3,  164,  193,  174,  175,  165,  150,
+ /*  1200 */    86,   87,    4,  180,  150,  248,  251,   93,   94,   95,
+ /*  1210 */   216,  180,   98,  251,  165,  221,  150,  149,    6,  165,
  /*  1220 */   129,  130,  131,  132,  133,  134,  193,  150,  174,  175,
- /*  1230 */   116,  165,   19,   20,  150,   22,  249,  252,  149,   26,
- /*  1240 */    27,  180,  165,  129,  130,  131,  132,  133,  134,  165,
- /*  1250 */    37,  174,  175,  150,    6,   19,   20,  150,   22,  150,
- /*  1260 */   150,  150,   26,   27,  149,  149,   13,  150,  165,   56,
- /*  1270 */   149,  159,  165,   37,  165,  165,  165,  174,  175,   66,
- /*  1280 */   146,  147,  165,  174,  175,   25,  152,  151,  154,  150,
- /*  1290 */   194,  151,   56,  116,  160,  150,  123,  202,  150,   86,
- /*  1300 */    87,  199,   66,  193,  165,  200,   93,   94,   95,  150,
- /*  1310 */   165,   98,  150,  165,  126,   22,  124,  150,  150,   26,
- /*  1320 */    27,  150,   86,   87,  165,  201,  150,  165,  194,   93,
- /*  1330 */    94,   95,  165,  165,   98,  150,  165,  122,  203,  125,
- /*  1340 */   227,  165,  129,  130,  131,  132,  133,  134,    5,  150,
- /*  1350 */   165,  135,  218,   10,   11,   12,   13,   14,  150,   66,
- /*  1360 */    17,  157,  118,  157,  165,  129,  130,  131,  132,  133,
- /*  1370 */   134,  150,  104,  165,   31,  210,   33,  176,  150,   86,
- /*  1380 */    87,  247,  174,  175,  150,   42,  165,   94,  121,  211,
- /*  1390 */   150,   98,  210,  165,  210,  174,  175,  211,   55,  165,
+ /*  1230 */   116,  165,   19,   20,  150,   22,  149,  151,  150,   26,
+ /*  1240 */    27,  149,  165,  129,  130,  131,  132,  133,  134,  165,
+ /*  1250 */    37,  174,  175,  165,  149,   19,   20,   13,   22,  150,
+ /*  1260 */   150,  150,   26,   27,  146,  147,  151,  150,   25,   56,
+ /*  1270 */   152,  159,  154,   37,  165,  165,  165,  193,  160,   66,
+ /*  1280 */   116,  193,  165,  174,  175,  174,  175,  194,  199,  150,
+ /*  1290 */   200,  126,   56,  124,  123,  150,  201,  122,  150,   86,
+ /*  1300 */    87,  150,   66,  193,  165,  202,   93,   94,   95,  150,
+ /*  1310 */   165,   98,  194,  165,  125,   22,  165,  150,  150,   26,
+ /*  1320 */    27,  135,   86,   87,  165,  174,  175,  203,  226,   93,
+ /*  1330 */    94,   95,  165,  165,   98,  150,  218,  150,  193,  157,
+ /*  1340 */   118,  157,  129,  130,  131,  132,  133,  134,    5,  104,
+ /*  1350 */   165,  211,  165,   10,   11,   12,   13,   14,  150,   66,
+ /*  1360 */    17,  174,  175,  210,  246,  129,  130,  131,  132,  133,
+ /*  1370 */   134,  150,  210,  165,   31,  121,   33,  150,  150,   86,
+ /*  1380 */    87,  176,  174,  175,  150,   42,  165,   94,  211,  210,
+ /*  1390 */   150,   98,  165,  165,  211,  174,  175,  150,   55,  165,
  /*  1400 */    57,  150,  174,  175,   61,  165,  150,   64,  174,  175,
- /*  1410 */   104,  211,   47,  150,  174,  175,  165,  176,  176,  150,
- /*  1420 */   103,  165,  129,  130,  131,  174,  175,  184,  165,  179,
- /*  1430 */   174,  175,  150,  178,  165,  176,   22,  174,  175,  230,
- /*  1440 */    92,  230,  184,  174,  175,  150,  176,  165,  105,  106,
- /*  1450 */   107,  150,  176,  176,  111,  156,  174,  175,  179,  116,
- /*  1460 */   165,   18,  157,  156,  238,  157,  165,  156,   45,  174,
- /*  1470 */   175,  157,  157,  135,  239,  174,  175,  156,  189,  157,
- /*  1480 */    68,  189,  139,  219,   22,  199,  157,   18,  192,  192,
- /*  1490 */   192,  189,  192,  199,  219,  243,  157,   40,  157,  157,
- /*  1500 */   243,   38,  153,  166,  233,  196,  233,  246,  198,  228,
- /*  1510 */   177,  177,  209,  177,  182,  199,  166,  177,  166,  199,
- /*  1520 */   242,  177,  242,  178,  148,  166,  196,  209,  209,   92,
- /*  1530 */   195,  208,  174,  186,  183,  174,  183,  191,  183,  253,
- /*  1540 */   236,  253,  186,  253,  253,  253,  253,  253,  253,  237,
+ /*  1410 */   150,  150,  165,  150,  174,  175,  165,  104,  150,  184,
+ /*  1420 */   150,  165,  129,  130,  131,  165,  165,  150,  165,  150,
+ /*  1430 */   150,  176,  150,  165,   47,  165,  150,  150,  176,  103,
+ /*  1440 */   150,   22,  165,  178,  165,  165,  179,  165,  105,  106,
+ /*  1450 */   107,  165,  165,  229,  111,  165,   92,  176,  229,  116,
+ /*  1460 */   184,  176,  179,  156,  176,  176,   18,  157,  156,  237,
+ /*  1470 */    45,  157,  156,  135,  157,  157,  238,  156,   68,  157,
+ /*  1480 */   189,  189,  139,  219,   22,  157,   18,  192,  192,  192,
+ /*  1490 */   192,  189,  219,  199,  157,  242,   40,  157,  199,  242,
+ /*  1500 */   153,  157,   38,  245,  196,  166,  232,  198,  177,  177,
+ /*  1510 */   232,  227,  209,  178,  166,  182,  166,  148,  177,  177,
+ /*  1520 */   209,  196,  177,  199,  209,  199,  166,  208,   92,  195,
+ /*  1530 */   174,  174,  183,  252,  183,  183,  252,  191,  252,  235,
+ /*  1540 */   186,  241,  241,  252,  186,  252,  252,  252,  252,  252,
+ /*  1550 */   252,  252,  252,  252,  252,  252,  236,
 };
-#define YY_SHIFT_USE_DFLT (-90)
+#define YY_SHIFT_USE_DFLT (-74)
 #define YY_SHIFT_COUNT (418)
-#define YY_SHIFT_MIN   (-89)
-#define YY_SHIFT_MAX   (1469)
+#define YY_SHIFT_MIN   (-73)
+#define YY_SHIFT_MAX   (1468)
 static const short yy_shift_ofst[] = {
- /*     0 */   993, 1114, 1343, 1114, 1213, 1213,   90,   90,    0,  -19,
- /*    10 */  1213, 1213, 1213, 1213, 1213,  352,  517,  721, 1091, 1213,
+ /*     0 */   975, 1114, 1343, 1114, 1213, 1213,   90,   90,    0,  -19,
+ /*    10 */  1213, 1213, 1213, 1213, 1213,  345,  445,  721, 1091, 1213,
  /*    20 */  1213, 1213, 1213, 1213, 1213, 1213, 1213, 1213, 1213, 1213,
  /*    30 */  1213, 1213, 1213, 1213, 1213, 1213, 1213, 1213, 1213, 1213,
  /*    40 */  1213, 1213, 1213, 1213, 1213, 1213, 1213, 1236, 1213, 1213,
  /*    50 */  1213, 1213, 1213, 1213, 1213, 1213, 1213, 1213, 1213, 1213,
- /*    60 */  1213,  -49,  199,  517,  517,  913,  913,  382, 1177,   55,
- /*    70 */   647,  573,  499,  425,  351,  277,  203,  129,  795,  795,
+ /*    60 */  1213,  199,  445,  445,  835,  835,  365, 1164,   55,  647,
+ /*    70 */   573,  499,  425,  351,  277,  203,  129,  795,  795,  795,
  /*    80 */   795,  795,  795,  795,  795,  795,  795,  795,  795,  795,
- /*    90 */   795,  795,  795,  795,  795,  795,  869,  795,  943, 1017,
- /*   100 */  1017,  -69,  -69,  -69,  -69,   -1,   -1,   58,  138,  -44,
- /*   110 */   517,  517,  517,  517,  517,  517,  517,  517,  517,  517,
- /*   120 */   517,  517,  517,  517,  517,  517,  202,  579,  517,  517,
- /*   130 */   517,  517,  517,  382,  885, 1437,  -90,  -90,  -90, 1293,
- /*   140 */    73,  272,  272,  309,  311,  297,  282,  216,  602,  538,
- /*   150 */   517,  517,  517,  517,  517,  517,  517,  517,  517,  517,
- /*   160 */   517,  517,  517,  517,  517,  517,  517,  517,  517,  517,
- /*   170 */   517,  517,  517,  517,  517,  517,  517,  517,  517,  517,
- /*   180 */   517,  517,  505,  231,  231,  231,  706,   64, 1177, 1177,
- /*   190 */  1177,  -90,  -90,  -90,  136,  168,  168,   12,  496,  496,
- /*   200 */   496,  506,  423,  512,  370,  349,  335,  149,  149,  149,
- /*   210 */   149,  604,  516,  149,  149,  508,    3,  299,  677,  871,
- /*   220 */   613,  613,  879,  871,  879,  144,  382,  226,  382,  226,
- /*   230 */   564,  226,  613,  226,  226,  404,  625,  625,  382,  426,
- /*   240 */   -89,  801, 1463, 1244, 1244, 1457, 1457, 1244, 1462, 1412,
- /*   250 */  1188, 1469, 1469, 1469, 1469, 1244, 1188, 1462, 1412, 1412,
- /*   260 */  1244, 1443, 1338, 1423, 1244, 1244, 1443, 1244, 1443, 1244,
- /*   270 */  1443, 1414, 1306, 1306, 1306, 1365, 1348, 1348, 1414, 1306,
- /*   280 */  1317, 1306, 1365, 1306, 1306, 1267, 1268, 1267, 1268, 1267,
- /*   290 */  1268, 1244, 1244, 1216, 1214, 1215, 1192, 1173, 1188, 1177,
- /*   300 */  1260, 1253, 1253, 1248, 1248, 1248, 1248,  -90,  -90,  -90,
- /*   310 */   -90,  -90,  -90,  939,  102,  614,   84,  133,   14,  837,
- /*   320 */   396,  829,  825,  796,  757,  751,  650,  357,  244,  107,
- /*   330 */    54,  305,  278, 1207, 1203, 1183, 1063, 1179, 1137, 1166,
- /*   340 */  1172, 1170, 1064, 1152, 1046, 1057, 1034, 1126, 1041, 1129,
- /*   350 */  1142, 1031, 1120, 1012, 1056, 1048, 1018, 1098, 1086, 1001,
- /*   360 */  1097, 1076, 1058,  971,  936, 1026, 1052, 1025, 1013, 1027,
- /*   370 */   967, 1044, 1032, 1050,  945,  949, 1028,  995, 1024, 1021,
- /*   380 */   963,  981,  928,  953,  951,  870,  876,  897,  838,  720,
- /*   390 */   828,  794,  820,  498,  642,  783,  657,  729,  642,  557,
- /*   400 */   507,  509,  497,  470,  478,  449,  294,  228,  443,   23,
- /*   410 */   152,  123,   68,  -20,  -42,   57,   39,   -3,    5,
+ /*    90 */   795,  795,  795,  795,  795,  869,  795,  943, 1017, 1017,
+ /*   100 */   -69,  -45,  -45,  -45,  -45,  -45,   -1,   58,  138,  100,
+ /*   110 */   445,  445,  445,  445,  445,  445,  445,  445,  445,  445,
+ /*   120 */   445,  445,  445,  445,  445,  445,  537,  438,  445,  445,
+ /*   130 */   445,  445,  445,  365,  807, 1436,  -74,  -74,  -74, 1293,
+ /*   140 */    73,  434,  434,  311,  314,  290,  283,  286,  540,  467,
+ /*   150 */   445,  445,  445,  445,  445,  445,  445,  445,  445,  445,
+ /*   160 */   445,  445,  445,  445,  445,  445,  445,  445,  445,  445,
+ /*   170 */   445,  445,  445,  445,  445,  445,  445,  445,  445,  445,
+ /*   180 */   445,  445,   65,  722,  722,  722,  688,  266, 1164, 1164,
+ /*   190 */  1164,  -74,  -74,  -74,  136,  168,  168,  234,  360,  360,
+ /*   200 */   360,  430,  372,  435,  352,  278,  126,  -36,  -36,  -36,
+ /*   210 */   -36,  421,  651,  -36,  -36,  592,  292,  212,  623,  158,
+ /*   220 */   204,  204,  505,  158,  505,  144,  365,  154,  365,  154,
+ /*   230 */   645,  154,  204,  154,  154,  535,  548,  548,  365,  387,
+ /*   240 */   508,  233, 1464, 1222, 1222, 1456, 1456, 1222, 1462, 1410,
+ /*   250 */  1165, 1468, 1468, 1468, 1468, 1222, 1165, 1462, 1410, 1410,
+ /*   260 */  1222, 1448, 1338, 1425, 1222, 1222, 1448, 1222, 1448, 1222,
+ /*   270 */  1448, 1419, 1313, 1313, 1313, 1387, 1364, 1364, 1419, 1313,
+ /*   280 */  1336, 1313, 1387, 1313, 1313, 1254, 1245, 1254, 1245, 1254,
+ /*   290 */  1245, 1222, 1222, 1186, 1189, 1175, 1169, 1171, 1165, 1164,
+ /*   300 */  1243, 1244, 1244, 1212, 1212, 1212, 1212,  -74,  -74,  -74,
+ /*   310 */   -74,  -74,  -74,  939,  104,  680,  571,  327,    1,  980,
+ /*   320 */    26,  972,  971,  946,  901,  870,  830,  806,   54,   21,
+ /*   330 */   -73,  510,  242, 1198, 1190, 1170, 1042, 1161, 1108, 1146,
+ /*   340 */  1141, 1132, 1015, 1127, 1026, 1034, 1020, 1107, 1004, 1116,
+ /*   350 */  1121, 1005, 1099,  951, 1043, 1003,  969, 1045, 1035,  950,
+ /*   360 */  1053, 1047, 1025,  942,  913,  992, 1019,  945,  984,  940,
+ /*   370 */   876,  904,  953,  896,  748,  804,  880,  786,  868,  819,
+ /*   380 */   805,  810,  773,  751,  766,  706,  716,  691,  681,  568,
+ /*   390 */   655,  638,  676,  516,  541,  594,  599,  567,  541,  534,
+ /*   400 */   507,  527,  498,  523,  466,  382,  409,  384,  357,    6,
+ /*   410 */   240,  224,  143,   62,   18,   71,   39,    9,    5,
 };
-#define YY_REDUCE_USE_DFLT (-222)
+#define YY_REDUCE_USE_DFLT (-142)
 #define YY_REDUCE_COUNT (312)
-#define YY_REDUCE_MIN   (-221)
-#define YY_REDUCE_MAX   (1376)
+#define YY_REDUCE_MIN   (-141)
+#define YY_REDUCE_MAX   (1369)
 static const short yy_reduce_ofst[] = {
- /*     0 */   310,  994, 1134,  221,  169,  157,   89,   18,   83,  301,
- /*    10 */   377,  316,  312,   16,  295,  238,  249,  391, 1301, 1295,
- /*    20 */  1282, 1269, 1263, 1256, 1251, 1240, 1234, 1228, 1221, 1208,
- /*    30 */  1109, 1103, 1077, 1054, 1022, 1016,  911,  908,  890,  888,
- /*    40 */   874,  816,  800,  760,  742,  739,  726,  684,  672,  665,
- /*    50 */   652,  612,  610,  594,  591,  578,  530,  528,  526,  524,
- /*    60 */   -72, -221,  399,  469,  445,  438,  143,  222,  359,  523,
- /*    70 */   523,  523,  523,  523,  523,  523,  523,  523,  523,  523,
- /*    80 */   523,  523,  523,  523,  523,  523,  523,  523,  523,  523,
- /*    90 */   523,  523,  523,  523,  523,  523,  523,  523,  523,  523,
- /*   100 */   523,  523,  523,  523,  523,  523,  523,  307,  523,  523,
- /*   110 */  1110,  678, 1033,  965,  962,  891,  814,  813,  744,  771,
- /*   120 */   691,  607,  522,  743,  686,  740,  328,  418,  670,  666,
- /*   130 */   596,  527,  529,  583,  523,  523,  523,  523,  523,  593,
- /*   140 */   823,  738,  712,  892, 1199, 1185, 1176, 1171,  673,  673,
- /*   150 */  1168, 1167, 1162, 1159, 1148, 1145, 1139, 1117, 1111, 1107,
- /*   160 */  1084, 1066, 1049, 1011, 1010, 1006, 1002,  999,  998,  973,
- /*   170 */   972,  970,  966,  964,  895,  894,  892,  833,  822,  762,
- /*   180 */   761,  229,  811,  804,  803,  389,  688,  808,  807,  737,
- /*   190 */   460,  464,  572,  584, 1356, 1361, 1358, 1347, 1355, 1353,
- /*   200 */  1351, 1323, 1335, 1346, 1335, 1335, 1335, 1335, 1335, 1335,
- /*   210 */  1335, 1312, 1304, 1335, 1335, 1323, 1359, 1330, 1376, 1320,
- /*   220 */  1319, 1318, 1280, 1316, 1278, 1345, 1352, 1344, 1350, 1340,
- /*   230 */  1332, 1336, 1303, 1334, 1333, 1281, 1273, 1271, 1337, 1310,
- /*   240 */  1309, 1349, 1261, 1342, 1341, 1257, 1252, 1339, 1275, 1302,
- /*   250 */  1294, 1300, 1298, 1297, 1296, 1329, 1286, 1264, 1292, 1289,
- /*   260 */  1322, 1321, 1235, 1226, 1315, 1314, 1311, 1308, 1307, 1305,
- /*   270 */  1299, 1279, 1277, 1276, 1270, 1258, 1211, 1209, 1250, 1259,
- /*   280 */  1255, 1242, 1243, 1241, 1201, 1200, 1184, 1186, 1182, 1178,
- /*   290 */  1165, 1206, 1204, 1113, 1135, 1095, 1124, 1105, 1102, 1096,
- /*   300 */  1112, 1140, 1136, 1121, 1116, 1115, 1089,  985,  961,  987,
- /*   310 */  1061, 1038, 1053,
+ /*     0 */  -141,  994, 1118,  223,  157,  -53,   93,   89,   83,  375,
+ /*    10 */   386,  381,  379,  308,  295,  325,  -47,   27, 1240, 1234,
+ /*    20 */  1228, 1221, 1208, 1187, 1151, 1111, 1109, 1077, 1054, 1022,
+ /*    30 */  1016, 1000,  911,  908,  906,  890,  888,  874,  834,  816,
+ /*    40 */   800,  760,  758,  755,  742,  739,  726,  685,  672,  668,
+ /*    50 */   665,  652,  611,  609,  607,  604,  591,  578,  526,  519,
+ /*    60 */   453,  474,  454,  461,  443,  245,  442,  473,  484,  484,
+ /*    70 */   484,  484,  484,  484,  484,  484,  484,  484,  484,  484,
+ /*    80 */   484,  484,  484,  484,  484,  484,  484,  484,  484,  484,
+ /*    90 */   484,  484,  484,  484,  484,  484,  484,  484,  484,  484,
+ /*   100 */   484,  484,  484,  484,  484,  484,  484,  130,  484,  484,
+ /*   110 */  1145,  909, 1110, 1088, 1084, 1033, 1002,  965,  820,  837,
+ /*   120 */   746,  686,  612,  817,  610,  919,  221,  563,  814,  813,
+ /*   130 */   744,  669,  470,  543,  484,  484,  484,  484,  484,  291,
+ /*   140 */   569,  671,  658,  970, 1290, 1287, 1286, 1282,  518,  518,
+ /*   150 */  1280, 1279, 1277, 1270, 1268, 1263, 1261, 1260, 1256, 1251,
+ /*   160 */  1247, 1227, 1185, 1168, 1167, 1159, 1148, 1139, 1117, 1066,
+ /*   170 */  1049, 1006,  998,  996,  995,  973,  970,  966,  964,  892,
+ /*   180 */   762,  -52,  881,  932,  802,  731,  619,  812,  664,  660,
+ /*   190 */   627,  392,  331,  124, 1358, 1357, 1356, 1354, 1352, 1351,
+ /*   200 */  1349, 1319, 1334, 1346, 1334, 1334, 1334, 1334, 1334, 1334,
+ /*   210 */  1334, 1320, 1304, 1334, 1334, 1319, 1360, 1325, 1369, 1326,
+ /*   220 */  1315, 1311, 1301, 1324, 1300, 1335, 1350, 1345, 1348, 1342,
+ /*   230 */  1333, 1341, 1303, 1332, 1331, 1284, 1278, 1274, 1339, 1309,
+ /*   240 */  1308, 1347, 1258, 1344, 1340, 1257, 1253, 1337, 1273, 1302,
+ /*   250 */  1299, 1298, 1297, 1296, 1295, 1328, 1294, 1264, 1292, 1291,
+ /*   260 */  1322, 1321, 1238, 1232, 1318, 1317, 1316, 1314, 1312, 1310,
+ /*   270 */  1307, 1283, 1289, 1288, 1285, 1276, 1229, 1224, 1267, 1281,
+ /*   280 */  1265, 1262, 1235, 1255, 1205, 1183, 1179, 1177, 1162, 1140,
+ /*   290 */  1153, 1184, 1182, 1102, 1124, 1103, 1095, 1090, 1089, 1093,
+ /*   300 */  1112, 1115, 1086, 1105, 1092, 1087, 1068,  962,  955,  957,
+ /*   310 */  1031, 1023, 1030,
 };
 static const YYACTIONTYPE yy_default[] = {
- /*     0 */   636,  872,  961,  961,  961,  872,  901,  901,  961,  760,
- /*    10 */   961,  961,  961,  961,  870,  961,  961,  935,  961,  961,
- /*    20 */   961,  961,  961,  961,  961,  961,  961,  961,  961,  961,
- /*    30 */   961,  961,  961,  961,  961,  961,  961,  961,  961,  961,
- /*    40 */   961,  961,  961,  961,  961,  961,  961,  961,  961,  961,
- /*    50 */   961,  961,  961,  961,  961,  961,  961,  961,  961,  961,
- /*    60 */   961,  844,  961,  961,  961,  901,  901,  675,  764,  795,
- /*    70 */   961,  961,  961,  961,  961,  961,  961,  961,  934,  936,
- /*    80 */   810,  809,  803,  802,  914,  775,  800,  793,  786,  797,
- /*    90 */   873,  866,  867,  865,  869,  874,  961,  796,  832,  850,
- /*   100 */   831,  849,  856,  848,  834,  843,  833,  667,  835,  836,
- /*   110 */   961,  961,  961,  961,  961,  961,  961,  961,  961,  961,
- /*   120 */   961,  961,  961,  961,  961,  961,  662,  729,  961,  961,
- /*   130 */   961,  961,  961,  961,  837,  838,  853,  852,  851,  961,
- /*   140 */   961,  961,  961,  961,  961,  961,  961,  961,  961,  961,
- /*   150 */   961,  941,  939,  961,  885,  961,  961,  961,  961,  961,
- /*   160 */   961,  961,  961,  961,  961,  961,  961,  961,  961,  961,
- /*   170 */   961,  961,  961,  961,  961,  961,  961,  961,  961,  961,
- /*   180 */   961,  642,  961,  760,  760,  760,  636,  961,  961,  961,
- /*   190 */   961,  953,  764,  754,  720,  961,  961,  961,  961,  961,
- /*   200 */   961,  961,  961,  961,  961,  961,  961,  805,  743,  924,
- /*   210 */   926,  961,  907,  741,  664,  762,  677,  752,  644,  799,
- /*   220 */   777,  777,  919,  799,  919,  701,  961,  789,  961,  789,
- /*   230 */   698,  789,  777,  789,  789,  868,  961,  961,  961,  761,
- /*   240 */   752,  961,  946,  768,  768,  938,  938,  768,  811,  733,
- /*   250 */   799,  740,  740,  740,  740,  768,  799,  811,  733,  733,
- /*   260 */   768,  659,  913,  911,  768,  768,  659,  768,  659,  768,
- /*   270 */   659,  878,  731,  731,  731,  716,  882,  882,  878,  731,
- /*   280 */   701,  731,  716,  731,  731,  781,  776,  781,  776,  781,
- /*   290 */   776,  768,  768,  961,  794,  782,  792,  790,  799,  961,
- /*   300 */   719,  652,  652,  641,  641,  641,  641,  958,  958,  953,
- /*   310 */   703,  703,  685,  961,  961,  961,  961,  961,  961,  961,
- /*   320 */   887,  961,  961,  961,  961,  961,  961,  961,  961,  961,
- /*   330 */   961,  961,  961,  961,  637,  948,  961,  961,  945,  961,
- /*   340 */   961,  961,  961,  961,  961,  961,  961,  961,  961,  961,
- /*   350 */   961,  961,  961,  961,  961,  961,  961,  961,  961,  917,
- /*   360 */   961,  961,  961,  961,  961,  961,  910,  909,  961,  961,
- /*   370 */   961,  961,  961,  961,  961,  961,  961,  961,  961,  961,
- /*   380 */   961,  961,  961,  961,  961,  961,  961,  961,  961,  961,
- /*   390 */   961,  961,  961,  961,  791,  961,  783,  961,  871,  961,
- /*   400 */   961,  961,  961,  961,  961,  961,  961,  961,  961,  746,
- /*   410 */   820,  961,  819,  823,  818,  669,  961,  650,  961,  633,
- /*   420 */   638,  957,  960,  959,  956,  955,  954,  949,  947,  944,
- /*   430 */   943,  942,  940,  937,  933,  891,  889,  896,  895,  894,
- /*   440 */   893,  892,  890,  888,  886,  806,  804,  801,  798,  932,
- /*   450 */   884,  742,  739,  738,  658,  950,  916,  925,  923,  812,
- /*   460 */   922,  921,  920,  918,  915,  902,  808,  807,  734,  876,
- /*   470 */   875,  661,  906,  905,  904,  908,  912,  903,  770,  660,
- /*   480 */   657,  666,  723,  722,  730,  728,  727,  726,  725,  724,
- /*   490 */   721,  668,  676,  687,  715,  700,  699,  881,  883,  880,
- /*   500 */   879,  708,  707,  713,  712,  711,  710,  709,  706,  705,
- /*   510 */   704,  697,  696,  702,  695,  718,  717,  714,  694,  737,
- /*   520 */   736,  735,  732,  693,  692,  691,  823,  690,  689,  829,
- /*   530 */   828,  816,  860,  757,  756,  755,  767,  766,  779,  778,
- /*   540 */   814,  813,  780,  765,  759,  758,  774,  773,  772,  771,
- /*   550 */   763,  753,  785,  788,  787,  784,  845,  862,  769,  859,
- /*   560 */   931,  930,  929,  928,  927,  864,  863,  830,  827,  680,
- /*   570 */   681,  900,  898,  899,  897,  683,  682,  679,  678,  861,
- /*   580 */   748,  747,  857,  854,  846,  841,  858,  855,  847,  842,
- /*   590 */   840,  839,  825,  824,  822,  821,  817,  826,  671,  749,
- /*   600 */   745,  744,  815,  751,  750,  688,  686,  684,  665,  663,
- /*   610 */   656,  654,  653,  655,  651,  649,  648,  647,  646,  645,
- /*   620 */   674,  673,  672,  670,  669,  643,  640,  639,  635,  634,
- /*   630 */   632,
+ /*     0 */   635,  870,  959,  959,  959,  870,  899,  899,  959,  759,
+ /*    10 */   959,  959,  959,  959,  868,  959,  959,  933,  959,  959,
+ /*    20 */   959,  959,  959,  959,  959,  959,  959,  959,  959,  959,
+ /*    30 */   959,  959,  959,  959,  959,  959,  959,  959,  959,  959,
+ /*    40 */   959,  959,  959,  959,  959,  959,  959,  959,  959,  959,
+ /*    50 */   959,  959,  959,  959,  959,  959,  959,  959,  959,  959,
+ /*    60 */   959,  959,  959,  959,  899,  899,  674,  763,  794,  959,
+ /*    70 */   959,  959,  959,  959,  959,  959,  959,  932,  934,  809,
+ /*    80 */   808,  802,  801,  912,  774,  799,  792,  785,  796,  871,
+ /*    90 */   864,  865,  863,  867,  872,  959,  795,  831,  848,  830,
+ /*   100 */   842,  847,  854,  846,  843,  833,  832,  666,  834,  835,
+ /*   110 */   959,  959,  959,  959,  959,  959,  959,  959,  959,  959,
+ /*   120 */   959,  959,  959,  959,  959,  959,  661,  728,  959,  959,
+ /*   130 */   959,  959,  959,  959,  836,  837,  851,  850,  849,  959,
+ /*   140 */   959,  959,  959,  959,  959,  959,  959,  959,  959,  959,
+ /*   150 */   959,  939,  937,  959,  883,  959,  959,  959,  959,  959,
+ /*   160 */   959,  959,  959,  959,  959,  959,  959,  959,  959,  959,
+ /*   170 */   959,  959,  959,  959,  959,  959,  959,  959,  959,  959,
+ /*   180 */   959,  641,  959,  759,  759,  759,  635,  959,  959,  959,
+ /*   190 */   959,  951,  763,  753,  719,  959,  959,  959,  959,  959,
+ /*   200 */   959,  959,  959,  959,  959,  959,  959,  804,  742,  922,
+ /*   210 */   924,  959,  905,  740,  663,  761,  676,  751,  643,  798,
+ /*   220 */   776,  776,  917,  798,  917,  700,  959,  788,  959,  788,
+ /*   230 */   697,  788,  776,  788,  788,  866,  959,  959,  959,  760,
+ /*   240 */   751,  959,  944,  767,  767,  936,  936,  767,  810,  732,
+ /*   250 */   798,  739,  739,  739,  739,  767,  798,  810,  732,  732,
+ /*   260 */   767,  658,  911,  909,  767,  767,  658,  767,  658,  767,
+ /*   270 */   658,  876,  730,  730,  730,  715,  880,  880,  876,  730,
+ /*   280 */   700,  730,  715,  730,  730,  780,  775,  780,  775,  780,
+ /*   290 */   775,  767,  767,  959,  793,  781,  791,  789,  798,  959,
+ /*   300 */   718,  651,  651,  640,  640,  640,  640,  956,  956,  951,
+ /*   310 */   702,  702,  684,  959,  959,  959,  959,  959,  959,  959,
+ /*   320 */   885,  959,  959,  959,  959,  959,  959,  959,  959,  959,
+ /*   330 */   959,  959,  959,  959,  636,  946,  959,  959,  943,  959,
+ /*   340 */   959,  959,  959,  959,  959,  959,  959,  959,  959,  959,
+ /*   350 */   959,  959,  959,  959,  959,  959,  959,  959,  959,  915,
+ /*   360 */   959,  959,  959,  959,  959,  959,  908,  907,  959,  959,
+ /*   370 */   959,  959,  959,  959,  959,  959,  959,  959,  959,  959,
+ /*   380 */   959,  959,  959,  959,  959,  959,  959,  959,  959,  959,
+ /*   390 */   959,  959,  959,  959,  790,  959,  782,  959,  869,  959,
+ /*   400 */   959,  959,  959,  959,  959,  959,  959,  959,  959,  745,
+ /*   410 */   819,  959,  818,  822,  817,  668,  959,  649,  959,  632,
+ /*   420 */   637,  955,  958,  957,  954,  953,  952,  947,  945,  942,
+ /*   430 */   941,  940,  938,  935,  931,  889,  887,  894,  893,  892,
+ /*   440 */   891,  890,  888,  886,  884,  805,  803,  800,  797,  930,
+ /*   450 */   882,  741,  738,  737,  657,  948,  914,  923,  921,  811,
+ /*   460 */   920,  919,  918,  916,  913,  900,  807,  806,  733,  874,
+ /*   470 */   873,  660,  904,  903,  902,  906,  910,  901,  769,  659,
+ /*   480 */   656,  665,  722,  721,  729,  727,  726,  725,  724,  723,
+ /*   490 */   720,  667,  675,  686,  714,  699,  698,  879,  881,  878,
+ /*   500 */   877,  707,  706,  712,  711,  710,  709,  708,  705,  704,
+ /*   510 */   703,  696,  695,  701,  694,  717,  716,  713,  693,  736,
+ /*   520 */   735,  734,  731,  692,  691,  690,  822,  689,  688,  828,
+ /*   530 */   827,  815,  858,  756,  755,  754,  766,  765,  778,  777,
+ /*   540 */   813,  812,  779,  764,  758,  757,  773,  772,  771,  770,
+ /*   550 */   762,  752,  784,  787,  786,  783,  860,  768,  857,  929,
+ /*   560 */   928,  927,  926,  925,  862,  861,  829,  826,  679,  680,
+ /*   570 */   898,  896,  897,  895,  682,  681,  678,  677,  859,  747,
+ /*   580 */   746,  855,  852,  844,  840,  856,  853,  845,  841,  839,
+ /*   590 */   838,  824,  823,  821,  820,  816,  825,  670,  748,  744,
+ /*   600 */   743,  814,  750,  749,  687,  685,  683,  664,  662,  655,
+ /*   610 */   653,  652,  654,  650,  648,  647,  646,  645,  644,  673,
+ /*   620 */   672,  671,  669,  668,  642,  639,  638,  634,  633,  631,
 };
 
 /* The next table maps tokens into fallback tokens.  If a construct
@@ -98476,15 +100301,14 @@
   "joinop",        "indexed_opt",   "on_opt",        "using_opt",   
   "joinop2",       "inscollist",    "sortlist",      "sortitem",    
   "nexprlist",     "setlist",       "insert_cmd",    "inscollist_opt",
-  "itemlist",      "exprlist",      "likeop",        "escape",      
-  "between_op",    "in_op",         "case_operand",  "case_exprlist",
-  "case_else",     "uniqueflag",    "collate",       "nmnum",       
-  "plus_opt",      "number",        "trigger_decl",  "trigger_cmd_list",
-  "trigger_time",  "trigger_event",  "foreach_clause",  "when_clause", 
-  "trigger_cmd",   "trnm",          "tridxby",       "database_kw_opt",
-  "key_opt",       "add_column_fullname",  "kwcolumn_opt",  "create_vtab", 
-  "vtabarglist",   "vtabarg",       "vtabargtoken",  "lp",          
-  "anylist",     
+  "itemlist",      "exprlist",      "likeop",        "between_op",  
+  "in_op",         "case_operand",  "case_exprlist",  "case_else",   
+  "uniqueflag",    "collate",       "nmnum",         "plus_opt",    
+  "number",        "trigger_decl",  "trigger_cmd_list",  "trigger_time",
+  "trigger_event",  "foreach_clause",  "when_clause",   "trigger_cmd", 
+  "trnm",          "tridxby",       "database_kw_opt",  "key_opt",     
+  "add_column_fullname",  "kwcolumn_opt",  "create_vtab",   "vtabarglist", 
+  "vtabarg",       "vtabargtoken",  "lp",            "anylist",     
 };
 #endif /* NDEBUG */
 
@@ -98704,124 +100528,123 @@
  /* 209 */ "likeop ::= NOT LIKE_KW",
  /* 210 */ "likeop ::= MATCH",
  /* 211 */ "likeop ::= NOT MATCH",
- /* 212 */ "escape ::= ESCAPE expr",
- /* 213 */ "escape ::=",
- /* 214 */ "expr ::= expr likeop expr escape",
- /* 215 */ "expr ::= expr ISNULL|NOTNULL",
- /* 216 */ "expr ::= expr NOT NULL",
- /* 217 */ "expr ::= expr IS expr",
- /* 218 */ "expr ::= expr IS NOT expr",
- /* 219 */ "expr ::= NOT expr",
- /* 220 */ "expr ::= BITNOT expr",
- /* 221 */ "expr ::= MINUS expr",
- /* 222 */ "expr ::= PLUS expr",
- /* 223 */ "between_op ::= BETWEEN",
- /* 224 */ "between_op ::= NOT BETWEEN",
- /* 225 */ "expr ::= expr between_op expr AND expr",
- /* 226 */ "in_op ::= IN",
- /* 227 */ "in_op ::= NOT IN",
- /* 228 */ "expr ::= expr in_op LP exprlist RP",
- /* 229 */ "expr ::= LP select RP",
- /* 230 */ "expr ::= expr in_op LP select RP",
- /* 231 */ "expr ::= expr in_op nm dbnm",
- /* 232 */ "expr ::= EXISTS LP select RP",
- /* 233 */ "expr ::= CASE case_operand case_exprlist case_else END",
- /* 234 */ "case_exprlist ::= case_exprlist WHEN expr THEN expr",
- /* 235 */ "case_exprlist ::= WHEN expr THEN expr",
- /* 236 */ "case_else ::= ELSE expr",
- /* 237 */ "case_else ::=",
- /* 238 */ "case_operand ::= expr",
- /* 239 */ "case_operand ::=",
- /* 240 */ "exprlist ::= nexprlist",
- /* 241 */ "exprlist ::=",
- /* 242 */ "nexprlist ::= nexprlist COMMA expr",
- /* 243 */ "nexprlist ::= expr",
- /* 244 */ "cmd ::= createkw uniqueflag INDEX ifnotexists nm dbnm ON nm LP idxlist RP",
- /* 245 */ "uniqueflag ::= UNIQUE",
- /* 246 */ "uniqueflag ::=",
- /* 247 */ "idxlist_opt ::=",
- /* 248 */ "idxlist_opt ::= LP idxlist RP",
- /* 249 */ "idxlist ::= idxlist COMMA nm collate sortorder",
- /* 250 */ "idxlist ::= nm collate sortorder",
- /* 251 */ "collate ::=",
- /* 252 */ "collate ::= COLLATE ids",
- /* 253 */ "cmd ::= DROP INDEX ifexists fullname",
- /* 254 */ "cmd ::= VACUUM",
- /* 255 */ "cmd ::= VACUUM nm",
- /* 256 */ "cmd ::= PRAGMA nm dbnm",
- /* 257 */ "cmd ::= PRAGMA nm dbnm EQ nmnum",
- /* 258 */ "cmd ::= PRAGMA nm dbnm LP nmnum RP",
- /* 259 */ "cmd ::= PRAGMA nm dbnm EQ minus_num",
- /* 260 */ "cmd ::= PRAGMA nm dbnm LP minus_num RP",
- /* 261 */ "nmnum ::= plus_num",
- /* 262 */ "nmnum ::= nm",
- /* 263 */ "nmnum ::= ON",
- /* 264 */ "nmnum ::= DELETE",
- /* 265 */ "nmnum ::= DEFAULT",
- /* 266 */ "plus_num ::= plus_opt number",
- /* 267 */ "minus_num ::= MINUS number",
- /* 268 */ "number ::= INTEGER|FLOAT",
- /* 269 */ "plus_opt ::= PLUS",
- /* 270 */ "plus_opt ::=",
- /* 271 */ "cmd ::= createkw trigger_decl BEGIN trigger_cmd_list END",
- /* 272 */ "trigger_decl ::= temp TRIGGER ifnotexists nm dbnm trigger_time trigger_event ON fullname foreach_clause when_clause",
- /* 273 */ "trigger_time ::= BEFORE",
- /* 274 */ "trigger_time ::= AFTER",
- /* 275 */ "trigger_time ::= INSTEAD OF",
- /* 276 */ "trigger_time ::=",
- /* 277 */ "trigger_event ::= DELETE|INSERT",
- /* 278 */ "trigger_event ::= UPDATE",
- /* 279 */ "trigger_event ::= UPDATE OF inscollist",
- /* 280 */ "foreach_clause ::=",
- /* 281 */ "foreach_clause ::= FOR EACH ROW",
- /* 282 */ "when_clause ::=",
- /* 283 */ "when_clause ::= WHEN expr",
- /* 284 */ "trigger_cmd_list ::= trigger_cmd_list trigger_cmd SEMI",
- /* 285 */ "trigger_cmd_list ::= trigger_cmd SEMI",
- /* 286 */ "trnm ::= nm",
- /* 287 */ "trnm ::= nm DOT nm",
- /* 288 */ "tridxby ::=",
- /* 289 */ "tridxby ::= INDEXED BY nm",
- /* 290 */ "tridxby ::= NOT INDEXED",
- /* 291 */ "trigger_cmd ::= UPDATE orconf trnm tridxby SET setlist where_opt",
- /* 292 */ "trigger_cmd ::= insert_cmd INTO trnm inscollist_opt VALUES LP itemlist RP",
- /* 293 */ "trigger_cmd ::= insert_cmd INTO trnm inscollist_opt select",
- /* 294 */ "trigger_cmd ::= DELETE FROM trnm tridxby where_opt",
- /* 295 */ "trigger_cmd ::= select",
- /* 296 */ "expr ::= RAISE LP IGNORE RP",
- /* 297 */ "expr ::= RAISE LP raisetype COMMA nm RP",
- /* 298 */ "raisetype ::= ROLLBACK",
- /* 299 */ "raisetype ::= ABORT",
- /* 300 */ "raisetype ::= FAIL",
- /* 301 */ "cmd ::= DROP TRIGGER ifexists fullname",
- /* 302 */ "cmd ::= ATTACH database_kw_opt expr AS expr key_opt",
- /* 303 */ "cmd ::= DETACH database_kw_opt expr",
- /* 304 */ "key_opt ::=",
- /* 305 */ "key_opt ::= KEY expr",
- /* 306 */ "database_kw_opt ::= DATABASE",
- /* 307 */ "database_kw_opt ::=",
- /* 308 */ "cmd ::= REINDEX",
- /* 309 */ "cmd ::= REINDEX nm dbnm",
- /* 310 */ "cmd ::= ANALYZE",
- /* 311 */ "cmd ::= ANALYZE nm dbnm",
- /* 312 */ "cmd ::= ALTER TABLE fullname RENAME TO nm",
- /* 313 */ "cmd ::= ALTER TABLE add_column_fullname ADD kwcolumn_opt column",
- /* 314 */ "add_column_fullname ::= fullname",
- /* 315 */ "kwcolumn_opt ::=",
- /* 316 */ "kwcolumn_opt ::= COLUMNKW",
- /* 317 */ "cmd ::= create_vtab",
- /* 318 */ "cmd ::= create_vtab LP vtabarglist RP",
- /* 319 */ "create_vtab ::= createkw VIRTUAL TABLE nm dbnm USING nm",
- /* 320 */ "vtabarglist ::= vtabarg",
- /* 321 */ "vtabarglist ::= vtabarglist COMMA vtabarg",
- /* 322 */ "vtabarg ::=",
- /* 323 */ "vtabarg ::= vtabarg vtabargtoken",
- /* 324 */ "vtabargtoken ::= ANY",
- /* 325 */ "vtabargtoken ::= lp anylist RP",
- /* 326 */ "lp ::= LP",
- /* 327 */ "anylist ::=",
- /* 328 */ "anylist ::= anylist LP anylist RP",
- /* 329 */ "anylist ::= anylist ANY",
+ /* 212 */ "expr ::= expr likeop expr",
+ /* 213 */ "expr ::= expr likeop expr ESCAPE expr",
+ /* 214 */ "expr ::= expr ISNULL|NOTNULL",
+ /* 215 */ "expr ::= expr NOT NULL",
+ /* 216 */ "expr ::= expr IS expr",
+ /* 217 */ "expr ::= expr IS NOT expr",
+ /* 218 */ "expr ::= NOT expr",
+ /* 219 */ "expr ::= BITNOT expr",
+ /* 220 */ "expr ::= MINUS expr",
+ /* 221 */ "expr ::= PLUS expr",
+ /* 222 */ "between_op ::= BETWEEN",
+ /* 223 */ "between_op ::= NOT BETWEEN",
+ /* 224 */ "expr ::= expr between_op expr AND expr",
+ /* 225 */ "in_op ::= IN",
+ /* 226 */ "in_op ::= NOT IN",
+ /* 227 */ "expr ::= expr in_op LP exprlist RP",
+ /* 228 */ "expr ::= LP select RP",
+ /* 229 */ "expr ::= expr in_op LP select RP",
+ /* 230 */ "expr ::= expr in_op nm dbnm",
+ /* 231 */ "expr ::= EXISTS LP select RP",
+ /* 232 */ "expr ::= CASE case_operand case_exprlist case_else END",
+ /* 233 */ "case_exprlist ::= case_exprlist WHEN expr THEN expr",
+ /* 234 */ "case_exprlist ::= WHEN expr THEN expr",
+ /* 235 */ "case_else ::= ELSE expr",
+ /* 236 */ "case_else ::=",
+ /* 237 */ "case_operand ::= expr",
+ /* 238 */ "case_operand ::=",
+ /* 239 */ "exprlist ::= nexprlist",
+ /* 240 */ "exprlist ::=",
+ /* 241 */ "nexprlist ::= nexprlist COMMA expr",
+ /* 242 */ "nexprlist ::= expr",
+ /* 243 */ "cmd ::= createkw uniqueflag INDEX ifnotexists nm dbnm ON nm LP idxlist RP",
+ /* 244 */ "uniqueflag ::= UNIQUE",
+ /* 245 */ "uniqueflag ::=",
+ /* 246 */ "idxlist_opt ::=",
+ /* 247 */ "idxlist_opt ::= LP idxlist RP",
+ /* 248 */ "idxlist ::= idxlist COMMA nm collate sortorder",
+ /* 249 */ "idxlist ::= nm collate sortorder",
+ /* 250 */ "collate ::=",
+ /* 251 */ "collate ::= COLLATE ids",
+ /* 252 */ "cmd ::= DROP INDEX ifexists fullname",
+ /* 253 */ "cmd ::= VACUUM",
+ /* 254 */ "cmd ::= VACUUM nm",
+ /* 255 */ "cmd ::= PRAGMA nm dbnm",
+ /* 256 */ "cmd ::= PRAGMA nm dbnm EQ nmnum",
+ /* 257 */ "cmd ::= PRAGMA nm dbnm LP nmnum RP",
+ /* 258 */ "cmd ::= PRAGMA nm dbnm EQ minus_num",
+ /* 259 */ "cmd ::= PRAGMA nm dbnm LP minus_num RP",
+ /* 260 */ "nmnum ::= plus_num",
+ /* 261 */ "nmnum ::= nm",
+ /* 262 */ "nmnum ::= ON",
+ /* 263 */ "nmnum ::= DELETE",
+ /* 264 */ "nmnum ::= DEFAULT",
+ /* 265 */ "plus_num ::= plus_opt number",
+ /* 266 */ "minus_num ::= MINUS number",
+ /* 267 */ "number ::= INTEGER|FLOAT",
+ /* 268 */ "plus_opt ::= PLUS",
+ /* 269 */ "plus_opt ::=",
+ /* 270 */ "cmd ::= createkw trigger_decl BEGIN trigger_cmd_list END",
+ /* 271 */ "trigger_decl ::= temp TRIGGER ifnotexists nm dbnm trigger_time trigger_event ON fullname foreach_clause when_clause",
+ /* 272 */ "trigger_time ::= BEFORE",
+ /* 273 */ "trigger_time ::= AFTER",
+ /* 274 */ "trigger_time ::= INSTEAD OF",
+ /* 275 */ "trigger_time ::=",
+ /* 276 */ "trigger_event ::= DELETE|INSERT",
+ /* 277 */ "trigger_event ::= UPDATE",
+ /* 278 */ "trigger_event ::= UPDATE OF inscollist",
+ /* 279 */ "foreach_clause ::=",
+ /* 280 */ "foreach_clause ::= FOR EACH ROW",
+ /* 281 */ "when_clause ::=",
+ /* 282 */ "when_clause ::= WHEN expr",
+ /* 283 */ "trigger_cmd_list ::= trigger_cmd_list trigger_cmd SEMI",
+ /* 284 */ "trigger_cmd_list ::= trigger_cmd SEMI",
+ /* 285 */ "trnm ::= nm",
+ /* 286 */ "trnm ::= nm DOT nm",
+ /* 287 */ "tridxby ::=",
+ /* 288 */ "tridxby ::= INDEXED BY nm",
+ /* 289 */ "tridxby ::= NOT INDEXED",
+ /* 290 */ "trigger_cmd ::= UPDATE orconf trnm tridxby SET setlist where_opt",
+ /* 291 */ "trigger_cmd ::= insert_cmd INTO trnm inscollist_opt VALUES LP itemlist RP",
+ /* 292 */ "trigger_cmd ::= insert_cmd INTO trnm inscollist_opt select",
+ /* 293 */ "trigger_cmd ::= DELETE FROM trnm tridxby where_opt",
+ /* 294 */ "trigger_cmd ::= select",
+ /* 295 */ "expr ::= RAISE LP IGNORE RP",
+ /* 296 */ "expr ::= RAISE LP raisetype COMMA nm RP",
+ /* 297 */ "raisetype ::= ROLLBACK",
+ /* 298 */ "raisetype ::= ABORT",
+ /* 299 */ "raisetype ::= FAIL",
+ /* 300 */ "cmd ::= DROP TRIGGER ifexists fullname",
+ /* 301 */ "cmd ::= ATTACH database_kw_opt expr AS expr key_opt",
+ /* 302 */ "cmd ::= DETACH database_kw_opt expr",
+ /* 303 */ "key_opt ::=",
+ /* 304 */ "key_opt ::= KEY expr",
+ /* 305 */ "database_kw_opt ::= DATABASE",
+ /* 306 */ "database_kw_opt ::=",
+ /* 307 */ "cmd ::= REINDEX",
+ /* 308 */ "cmd ::= REINDEX nm dbnm",
+ /* 309 */ "cmd ::= ANALYZE",
+ /* 310 */ "cmd ::= ANALYZE nm dbnm",
+ /* 311 */ "cmd ::= ALTER TABLE fullname RENAME TO nm",
+ /* 312 */ "cmd ::= ALTER TABLE add_column_fullname ADD kwcolumn_opt column",
+ /* 313 */ "add_column_fullname ::= fullname",
+ /* 314 */ "kwcolumn_opt ::=",
+ /* 315 */ "kwcolumn_opt ::= COLUMNKW",
+ /* 316 */ "cmd ::= create_vtab",
+ /* 317 */ "cmd ::= create_vtab LP vtabarglist RP",
+ /* 318 */ "create_vtab ::= createkw VIRTUAL TABLE nm dbnm USING nm",
+ /* 319 */ "vtabarglist ::= vtabarg",
+ /* 320 */ "vtabarglist ::= vtabarglist COMMA vtabarg",
+ /* 321 */ "vtabarg ::=",
+ /* 322 */ "vtabarg ::= vtabarg vtabargtoken",
+ /* 323 */ "vtabargtoken ::= ANY",
+ /* 324 */ "vtabargtoken ::= lp anylist RP",
+ /* 325 */ "lp ::= LP",
+ /* 326 */ "anylist ::=",
+ /* 327 */ "anylist ::= anylist LP anylist RP",
+ /* 328 */ "anylist ::= anylist ANY",
 };
 #endif /* NDEBUG */
 
@@ -98903,14 +100726,13 @@
     case 160: /* select */
     case 194: /* oneselect */
 {
-sqlite3SelectDelete(pParse->db, (yypminor->yy3));
+sqlite3SelectDelete(pParse->db, (yypminor->yy387));
 }
       break;
     case 174: /* term */
     case 175: /* expr */
-    case 223: /* escape */
 {
-sqlite3ExprDelete(pParse->db, (yypminor->yy346).pExpr);
+sqlite3ExprDelete(pParse->db, (yypminor->yy118).pExpr);
 }
       break;
     case 179: /* idxlist_opt */
@@ -98924,9 +100746,9 @@
     case 217: /* setlist */
     case 220: /* itemlist */
     case 221: /* exprlist */
-    case 227: /* case_exprlist */
+    case 226: /* case_exprlist */
 {
-sqlite3ExprListDelete(pParse->db, (yypminor->yy14));
+sqlite3ExprListDelete(pParse->db, (yypminor->yy322));
 }
       break;
     case 193: /* fullname */
@@ -98934,37 +100756,37 @@
     case 206: /* seltablist */
     case 207: /* stl_prefix */
 {
-sqlite3SrcListDelete(pParse->db, (yypminor->yy65));
+sqlite3SrcListDelete(pParse->db, (yypminor->yy259));
 }
       break;
     case 199: /* where_opt */
     case 201: /* having_opt */
     case 210: /* on_opt */
     case 215: /* sortitem */
-    case 226: /* case_operand */
-    case 228: /* case_else */
-    case 239: /* when_clause */
-    case 244: /* key_opt */
+    case 225: /* case_operand */
+    case 227: /* case_else */
+    case 238: /* when_clause */
+    case 243: /* key_opt */
 {
-sqlite3ExprDelete(pParse->db, (yypminor->yy132));
+sqlite3ExprDelete(pParse->db, (yypminor->yy314));
 }
       break;
     case 211: /* using_opt */
     case 213: /* inscollist */
     case 219: /* inscollist_opt */
 {
-sqlite3IdListDelete(pParse->db, (yypminor->yy408));
+sqlite3IdListDelete(pParse->db, (yypminor->yy384));
 }
       break;
-    case 235: /* trigger_cmd_list */
-    case 240: /* trigger_cmd */
+    case 234: /* trigger_cmd_list */
+    case 239: /* trigger_cmd */
 {
-sqlite3DeleteTriggerStep(pParse->db, (yypminor->yy473));
+sqlite3DeleteTriggerStep(pParse->db, (yypminor->yy203));
 }
       break;
-    case 237: /* trigger_event */
+    case 236: /* trigger_event */
 {
-sqlite3IdListDelete(pParse->db, (yypminor->yy378).b);
+sqlite3IdListDelete(pParse->db, (yypminor->yy90).b);
 }
       break;
     default:  break;   /* If no destructor action specified: do nothing */
@@ -99422,47 +101244,46 @@
   { 222, 2 },
   { 222, 1 },
   { 222, 2 },
+  { 175, 3 },
+  { 175, 5 },
+  { 175, 2 },
+  { 175, 3 },
+  { 175, 3 },
+  { 175, 4 },
+  { 175, 2 },
+  { 175, 2 },
+  { 175, 2 },
+  { 175, 2 },
+  { 223, 1 },
   { 223, 2 },
-  { 223, 0 },
-  { 175, 4 },
-  { 175, 2 },
-  { 175, 3 },
-  { 175, 3 },
-  { 175, 4 },
-  { 175, 2 },
-  { 175, 2 },
-  { 175, 2 },
-  { 175, 2 },
+  { 175, 5 },
   { 224, 1 },
   { 224, 2 },
   { 175, 5 },
-  { 225, 1 },
-  { 225, 2 },
-  { 175, 5 },
   { 175, 3 },
   { 175, 5 },
   { 175, 4 },
   { 175, 4 },
   { 175, 5 },
-  { 227, 5 },
-  { 227, 4 },
-  { 228, 2 },
-  { 228, 0 },
-  { 226, 1 },
-  { 226, 0 },
+  { 226, 5 },
+  { 226, 4 },
+  { 227, 2 },
+  { 227, 0 },
+  { 225, 1 },
+  { 225, 0 },
   { 221, 1 },
   { 221, 0 },
   { 216, 3 },
   { 216, 1 },
   { 147, 11 },
-  { 229, 1 },
-  { 229, 0 },
+  { 228, 1 },
+  { 228, 0 },
   { 179, 0 },
   { 179, 3 },
   { 187, 5 },
   { 187, 3 },
-  { 230, 0 },
-  { 230, 2 },
+  { 229, 0 },
+  { 229, 2 },
   { 147, 4 },
   { 147, 1 },
   { 147, 2 },
@@ -99471,41 +101292,41 @@
   { 147, 6 },
   { 147, 5 },
   { 147, 6 },
-  { 231, 1 },
-  { 231, 1 },
-  { 231, 1 },
-  { 231, 1 },
-  { 231, 1 },
+  { 230, 1 },
+  { 230, 1 },
+  { 230, 1 },
+  { 230, 1 },
+  { 230, 1 },
   { 170, 2 },
   { 171, 2 },
-  { 233, 1 },
   { 232, 1 },
-  { 232, 0 },
+  { 231, 1 },
+  { 231, 0 },
   { 147, 5 },
-  { 234, 11 },
+  { 233, 11 },
+  { 235, 1 },
+  { 235, 1 },
+  { 235, 2 },
+  { 235, 0 },
   { 236, 1 },
   { 236, 1 },
-  { 236, 2 },
-  { 236, 0 },
-  { 237, 1 },
-  { 237, 1 },
+  { 236, 3 },
+  { 237, 0 },
   { 237, 3 },
   { 238, 0 },
-  { 238, 3 },
-  { 239, 0 },
-  { 239, 2 },
-  { 235, 3 },
-  { 235, 2 },
-  { 241, 1 },
-  { 241, 3 },
-  { 242, 0 },
-  { 242, 3 },
-  { 242, 2 },
-  { 240, 7 },
-  { 240, 8 },
-  { 240, 5 },
-  { 240, 5 },
+  { 238, 2 },
+  { 234, 3 },
+  { 234, 2 },
   { 240, 1 },
+  { 240, 3 },
+  { 241, 0 },
+  { 241, 3 },
+  { 241, 2 },
+  { 239, 7 },
+  { 239, 8 },
+  { 239, 5 },
+  { 239, 5 },
+  { 239, 1 },
   { 175, 4 },
   { 175, 6 },
   { 191, 1 },
@@ -99514,32 +101335,32 @@
   { 147, 4 },
   { 147, 6 },
   { 147, 3 },
-  { 244, 0 },
-  { 244, 2 },
-  { 243, 1 },
   { 243, 0 },
+  { 243, 2 },
+  { 242, 1 },
+  { 242, 0 },
   { 147, 1 },
   { 147, 3 },
   { 147, 1 },
   { 147, 3 },
   { 147, 6 },
   { 147, 6 },
+  { 244, 1 },
+  { 245, 0 },
   { 245, 1 },
-  { 246, 0 },
-  { 246, 1 },
   { 147, 1 },
   { 147, 4 },
-  { 247, 7 },
-  { 248, 1 },
-  { 248, 3 },
-  { 249, 0 },
-  { 249, 2 },
+  { 246, 7 },
+  { 247, 1 },
+  { 247, 3 },
+  { 248, 0 },
+  { 248, 2 },
+  { 249, 1 },
+  { 249, 3 },
   { 250, 1 },
-  { 250, 3 },
-  { 251, 1 },
-  { 252, 0 },
-  { 252, 4 },
-  { 252, 2 },
+  { 251, 0 },
+  { 251, 4 },
+  { 251, 2 },
 };
 
 static void yy_accept(yyParser*);  /* Forward Declaration */
@@ -99607,17 +101428,17 @@
 { sqlite3FinishCoding(pParse); }
         break;
       case 9: /* cmd ::= BEGIN transtype trans_opt */
-{sqlite3BeginTransaction(pParse, yymsp[-1].minor.yy328);}
+{sqlite3BeginTransaction(pParse, yymsp[-1].minor.yy4);}
         break;
       case 13: /* transtype ::= */
-{yygotominor.yy328 = TK_DEFERRED;}
+{yygotominor.yy4 = TK_DEFERRED;}
         break;
       case 14: /* transtype ::= DEFERRED */
       case 15: /* transtype ::= IMMEDIATE */ yytestcase(yyruleno==15);
       case 16: /* transtype ::= EXCLUSIVE */ yytestcase(yyruleno==16);
       case 115: /* multiselect_op ::= UNION */ yytestcase(yyruleno==115);
       case 117: /* multiselect_op ::= EXCEPT|INTERSECT */ yytestcase(yyruleno==117);
-{yygotominor.yy328 = yymsp[0].major;}
+{yygotominor.yy4 = yymsp[0].major;}
         break;
       case 17: /* cmd ::= COMMIT trans_opt */
       case 18: /* cmd ::= END trans_opt */ yytestcase(yyruleno==18);
@@ -99643,7 +101464,7 @@
         break;
       case 26: /* create_table ::= createkw temp TABLE ifnotexists nm dbnm */
 {
-   sqlite3StartTable(pParse,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy0,yymsp[-4].minor.yy328,0,0,yymsp[-2].minor.yy328);
+   sqlite3StartTable(pParse,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy0,yymsp[-4].minor.yy4,0,0,yymsp[-2].minor.yy4);
 }
         break;
       case 27: /* createkw ::= CREATE */
@@ -99662,9 +101483,9 @@
       case 109: /* ifexists ::= */ yytestcase(yyruleno==109);
       case 120: /* distinct ::= ALL */ yytestcase(yyruleno==120);
       case 121: /* distinct ::= */ yytestcase(yyruleno==121);
-      case 223: /* between_op ::= BETWEEN */ yytestcase(yyruleno==223);
-      case 226: /* in_op ::= IN */ yytestcase(yyruleno==226);
-{yygotominor.yy328 = 0;}
+      case 222: /* between_op ::= BETWEEN */ yytestcase(yyruleno==222);
+      case 225: /* in_op ::= IN */ yytestcase(yyruleno==225);
+{yygotominor.yy4 = 0;}
         break;
       case 29: /* ifnotexists ::= IF NOT EXISTS */
       case 30: /* temp ::= TEMP */ yytestcase(yyruleno==30);
@@ -99672,9 +101493,9 @@
       case 86: /* init_deferred_pred_opt ::= INITIALLY DEFERRED */ yytestcase(yyruleno==86);
       case 108: /* ifexists ::= IF EXISTS */ yytestcase(yyruleno==108);
       case 119: /* distinct ::= DISTINCT */ yytestcase(yyruleno==119);
-      case 224: /* between_op ::= NOT BETWEEN */ yytestcase(yyruleno==224);
-      case 227: /* in_op ::= NOT IN */ yytestcase(yyruleno==227);
-{yygotominor.yy328 = 1;}
+      case 223: /* between_op ::= NOT BETWEEN */ yytestcase(yyruleno==223);
+      case 226: /* in_op ::= NOT IN */ yytestcase(yyruleno==226);
+{yygotominor.yy4 = 1;}
         break;
       case 32: /* create_table_args ::= LP columnlist conslist_opt RP */
 {
@@ -99683,8 +101504,8 @@
         break;
       case 33: /* create_table_args ::= AS select */
 {
-  sqlite3EndTable(pParse,0,0,yymsp[0].minor.yy3);
-  sqlite3SelectDelete(pParse->db, yymsp[0].minor.yy3);
+  sqlite3EndTable(pParse,0,0,yymsp[0].minor.yy387);
+  sqlite3SelectDelete(pParse->db, yymsp[0].minor.yy387);
 }
         break;
       case 36: /* column ::= columnid type carglist */
@@ -99711,16 +101532,16 @@
       case 128: /* as ::= ids */ yytestcase(yyruleno==128);
       case 138: /* dbnm ::= DOT nm */ yytestcase(yyruleno==138);
       case 147: /* indexed_opt ::= INDEXED BY nm */ yytestcase(yyruleno==147);
-      case 252: /* collate ::= COLLATE ids */ yytestcase(yyruleno==252);
-      case 261: /* nmnum ::= plus_num */ yytestcase(yyruleno==261);
-      case 262: /* nmnum ::= nm */ yytestcase(yyruleno==262);
-      case 263: /* nmnum ::= ON */ yytestcase(yyruleno==263);
-      case 264: /* nmnum ::= DELETE */ yytestcase(yyruleno==264);
-      case 265: /* nmnum ::= DEFAULT */ yytestcase(yyruleno==265);
-      case 266: /* plus_num ::= plus_opt number */ yytestcase(yyruleno==266);
-      case 267: /* minus_num ::= MINUS number */ yytestcase(yyruleno==267);
-      case 268: /* number ::= INTEGER|FLOAT */ yytestcase(yyruleno==268);
-      case 286: /* trnm ::= nm */ yytestcase(yyruleno==286);
+      case 251: /* collate ::= COLLATE ids */ yytestcase(yyruleno==251);
+      case 260: /* nmnum ::= plus_num */ yytestcase(yyruleno==260);
+      case 261: /* nmnum ::= nm */ yytestcase(yyruleno==261);
+      case 262: /* nmnum ::= ON */ yytestcase(yyruleno==262);
+      case 263: /* nmnum ::= DELETE */ yytestcase(yyruleno==263);
+      case 264: /* nmnum ::= DEFAULT */ yytestcase(yyruleno==264);
+      case 265: /* plus_num ::= plus_opt number */ yytestcase(yyruleno==265);
+      case 266: /* minus_num ::= MINUS number */ yytestcase(yyruleno==266);
+      case 267: /* number ::= INTEGER|FLOAT */ yytestcase(yyruleno==267);
+      case 285: /* trnm ::= nm */ yytestcase(yyruleno==285);
 {yygotominor.yy0 = yymsp[0].minor.yy0;}
         break;
       case 45: /* type ::= typetoken */
@@ -99743,17 +101564,17 @@
         break;
       case 57: /* ccons ::= DEFAULT term */
       case 59: /* ccons ::= DEFAULT PLUS term */ yytestcase(yyruleno==59);
-{sqlite3AddDefaultValue(pParse,&yymsp[0].minor.yy346);}
+{sqlite3AddDefaultValue(pParse,&yymsp[0].minor.yy118);}
         break;
       case 58: /* ccons ::= DEFAULT LP expr RP */
-{sqlite3AddDefaultValue(pParse,&yymsp[-1].minor.yy346);}
+{sqlite3AddDefaultValue(pParse,&yymsp[-1].minor.yy118);}
         break;
       case 60: /* ccons ::= DEFAULT MINUS term */
 {
   ExprSpan v;
-  v.pExpr = sqlite3PExpr(pParse, TK_UMINUS, yymsp[0].minor.yy346.pExpr, 0, 0);
+  v.pExpr = sqlite3PExpr(pParse, TK_UMINUS, yymsp[0].minor.yy118.pExpr, 0, 0);
   v.zStart = yymsp[-1].minor.yy0.z;
-  v.zEnd = yymsp[0].minor.yy346.zEnd;
+  v.zEnd = yymsp[0].minor.yy118.zEnd;
   sqlite3AddDefaultValue(pParse,&v);
 }
         break;
@@ -99765,62 +101586,62 @@
 }
         break;
       case 63: /* ccons ::= NOT NULL onconf */
-{sqlite3AddNotNull(pParse, yymsp[0].minor.yy328);}
+{sqlite3AddNotNull(pParse, yymsp[0].minor.yy4);}
         break;
       case 64: /* ccons ::= PRIMARY KEY sortorder onconf autoinc */
-{sqlite3AddPrimaryKey(pParse,0,yymsp[-1].minor.yy328,yymsp[0].minor.yy328,yymsp[-2].minor.yy328);}
+{sqlite3AddPrimaryKey(pParse,0,yymsp[-1].minor.yy4,yymsp[0].minor.yy4,yymsp[-2].minor.yy4);}
         break;
       case 65: /* ccons ::= UNIQUE onconf */
-{sqlite3CreateIndex(pParse,0,0,0,0,yymsp[0].minor.yy328,0,0,0,0);}
+{sqlite3CreateIndex(pParse,0,0,0,0,yymsp[0].minor.yy4,0,0,0,0);}
         break;
       case 66: /* ccons ::= CHECK LP expr RP */
-{sqlite3AddCheckConstraint(pParse,yymsp[-1].minor.yy346.pExpr);}
+{sqlite3AddCheckConstraint(pParse,yymsp[-1].minor.yy118.pExpr);}
         break;
       case 67: /* ccons ::= REFERENCES nm idxlist_opt refargs */
-{sqlite3CreateForeignKey(pParse,0,&yymsp[-2].minor.yy0,yymsp[-1].minor.yy14,yymsp[0].minor.yy328);}
+{sqlite3CreateForeignKey(pParse,0,&yymsp[-2].minor.yy0,yymsp[-1].minor.yy322,yymsp[0].minor.yy4);}
         break;
       case 68: /* ccons ::= defer_subclause */
-{sqlite3DeferForeignKey(pParse,yymsp[0].minor.yy328);}
+{sqlite3DeferForeignKey(pParse,yymsp[0].minor.yy4);}
         break;
       case 69: /* ccons ::= COLLATE ids */
 {sqlite3AddCollateType(pParse, &yymsp[0].minor.yy0);}
         break;
       case 72: /* refargs ::= */
-{ yygotominor.yy328 = OE_None*0x0101; /* EV: R-19803-45884 */}
+{ yygotominor.yy4 = OE_None*0x0101; /* EV: R-19803-45884 */}
         break;
       case 73: /* refargs ::= refargs refarg */
-{ yygotominor.yy328 = (yymsp[-1].minor.yy328 & ~yymsp[0].minor.yy429.mask) | yymsp[0].minor.yy429.value; }
+{ yygotominor.yy4 = (yymsp[-1].minor.yy4 & ~yymsp[0].minor.yy215.mask) | yymsp[0].minor.yy215.value; }
         break;
       case 74: /* refarg ::= MATCH nm */
       case 75: /* refarg ::= ON INSERT refact */ yytestcase(yyruleno==75);
-{ yygotominor.yy429.value = 0;     yygotominor.yy429.mask = 0x000000; }
+{ yygotominor.yy215.value = 0;     yygotominor.yy215.mask = 0x000000; }
         break;
       case 76: /* refarg ::= ON DELETE refact */
-{ yygotominor.yy429.value = yymsp[0].minor.yy328;     yygotominor.yy429.mask = 0x0000ff; }
+{ yygotominor.yy215.value = yymsp[0].minor.yy4;     yygotominor.yy215.mask = 0x0000ff; }
         break;
       case 77: /* refarg ::= ON UPDATE refact */
-{ yygotominor.yy429.value = yymsp[0].minor.yy328<<8;  yygotominor.yy429.mask = 0x00ff00; }
+{ yygotominor.yy215.value = yymsp[0].minor.yy4<<8;  yygotominor.yy215.mask = 0x00ff00; }
         break;
       case 78: /* refact ::= SET NULL */
-{ yygotominor.yy328 = OE_SetNull;  /* EV: R-33326-45252 */}
+{ yygotominor.yy4 = OE_SetNull;  /* EV: R-33326-45252 */}
         break;
       case 79: /* refact ::= SET DEFAULT */
-{ yygotominor.yy328 = OE_SetDflt;  /* EV: R-33326-45252 */}
+{ yygotominor.yy4 = OE_SetDflt;  /* EV: R-33326-45252 */}
         break;
       case 80: /* refact ::= CASCADE */
-{ yygotominor.yy328 = OE_Cascade;  /* EV: R-33326-45252 */}
+{ yygotominor.yy4 = OE_Cascade;  /* EV: R-33326-45252 */}
         break;
       case 81: /* refact ::= RESTRICT */
-{ yygotominor.yy328 = OE_Restrict; /* EV: R-33326-45252 */}
+{ yygotominor.yy4 = OE_Restrict; /* EV: R-33326-45252 */}
         break;
       case 82: /* refact ::= NO ACTION */
-{ yygotominor.yy328 = OE_None;     /* EV: R-33326-45252 */}
+{ yygotominor.yy4 = OE_None;     /* EV: R-33326-45252 */}
         break;
       case 84: /* defer_subclause ::= DEFERRABLE init_deferred_pred_opt */
       case 99: /* defer_subclause_opt ::= defer_subclause */ yytestcase(yyruleno==99);
       case 101: /* onconf ::= ON CONFLICT resolvetype */ yytestcase(yyruleno==101);
       case 104: /* resolvetype ::= raisetype */ yytestcase(yyruleno==104);
-{yygotominor.yy328 = yymsp[0].minor.yy328;}
+{yygotominor.yy4 = yymsp[0].minor.yy4;}
         break;
       case 88: /* conslist_opt ::= */
 {yygotominor.yy0.n = 0; yygotominor.yy0.z = 0;}
@@ -99829,101 +101650,101 @@
 {yygotominor.yy0 = yymsp[-1].minor.yy0;}
         break;
       case 94: /* tcons ::= PRIMARY KEY LP idxlist autoinc RP onconf */
-{sqlite3AddPrimaryKey(pParse,yymsp[-3].minor.yy14,yymsp[0].minor.yy328,yymsp[-2].minor.yy328,0);}
+{sqlite3AddPrimaryKey(pParse,yymsp[-3].minor.yy322,yymsp[0].minor.yy4,yymsp[-2].minor.yy4,0);}
         break;
       case 95: /* tcons ::= UNIQUE LP idxlist RP onconf */
-{sqlite3CreateIndex(pParse,0,0,0,yymsp[-2].minor.yy14,yymsp[0].minor.yy328,0,0,0,0);}
+{sqlite3CreateIndex(pParse,0,0,0,yymsp[-2].minor.yy322,yymsp[0].minor.yy4,0,0,0,0);}
         break;
       case 96: /* tcons ::= CHECK LP expr RP onconf */
-{sqlite3AddCheckConstraint(pParse,yymsp[-2].minor.yy346.pExpr);}
+{sqlite3AddCheckConstraint(pParse,yymsp[-2].minor.yy118.pExpr);}
         break;
       case 97: /* tcons ::= FOREIGN KEY LP idxlist RP REFERENCES nm idxlist_opt refargs defer_subclause_opt */
 {
-    sqlite3CreateForeignKey(pParse, yymsp[-6].minor.yy14, &yymsp[-3].minor.yy0, yymsp[-2].minor.yy14, yymsp[-1].minor.yy328);
-    sqlite3DeferForeignKey(pParse, yymsp[0].minor.yy328);
+    sqlite3CreateForeignKey(pParse, yymsp[-6].minor.yy322, &yymsp[-3].minor.yy0, yymsp[-2].minor.yy322, yymsp[-1].minor.yy4);
+    sqlite3DeferForeignKey(pParse, yymsp[0].minor.yy4);
 }
         break;
       case 100: /* onconf ::= */
-{yygotominor.yy328 = OE_Default;}
+{yygotominor.yy4 = OE_Default;}
         break;
       case 102: /* orconf ::= */
-{yygotominor.yy186 = OE_Default;}
+{yygotominor.yy210 = OE_Default;}
         break;
       case 103: /* orconf ::= OR resolvetype */
-{yygotominor.yy186 = (u8)yymsp[0].minor.yy328;}
+{yygotominor.yy210 = (u8)yymsp[0].minor.yy4;}
         break;
       case 105: /* resolvetype ::= IGNORE */
-{yygotominor.yy328 = OE_Ignore;}
+{yygotominor.yy4 = OE_Ignore;}
         break;
       case 106: /* resolvetype ::= REPLACE */
-{yygotominor.yy328 = OE_Replace;}
+{yygotominor.yy4 = OE_Replace;}
         break;
       case 107: /* cmd ::= DROP TABLE ifexists fullname */
 {
-  sqlite3DropTable(pParse, yymsp[0].minor.yy65, 0, yymsp[-1].minor.yy328);
+  sqlite3DropTable(pParse, yymsp[0].minor.yy259, 0, yymsp[-1].minor.yy4);
 }
         break;
       case 110: /* cmd ::= createkw temp VIEW ifnotexists nm dbnm AS select */
 {
-  sqlite3CreateView(pParse, &yymsp[-7].minor.yy0, &yymsp[-3].minor.yy0, &yymsp[-2].minor.yy0, yymsp[0].minor.yy3, yymsp[-6].minor.yy328, yymsp[-4].minor.yy328);
+  sqlite3CreateView(pParse, &yymsp[-7].minor.yy0, &yymsp[-3].minor.yy0, &yymsp[-2].minor.yy0, yymsp[0].minor.yy387, yymsp[-6].minor.yy4, yymsp[-4].minor.yy4);
 }
         break;
       case 111: /* cmd ::= DROP VIEW ifexists fullname */
 {
-  sqlite3DropTable(pParse, yymsp[0].minor.yy65, 1, yymsp[-1].minor.yy328);
+  sqlite3DropTable(pParse, yymsp[0].minor.yy259, 1, yymsp[-1].minor.yy4);
 }
         break;
       case 112: /* cmd ::= select */
 {
   SelectDest dest = {SRT_Output, 0, 0, 0, 0};
-  sqlite3Select(pParse, yymsp[0].minor.yy3, &dest);
-  sqlite3SelectDelete(pParse->db, yymsp[0].minor.yy3);
+  sqlite3Select(pParse, yymsp[0].minor.yy387, &dest);
+  sqlite3SelectDelete(pParse->db, yymsp[0].minor.yy387);
 }
         break;
       case 113: /* select ::= oneselect */
-{yygotominor.yy3 = yymsp[0].minor.yy3;}
+{yygotominor.yy387 = yymsp[0].minor.yy387;}
         break;
       case 114: /* select ::= select multiselect_op oneselect */
 {
-  if( yymsp[0].minor.yy3 ){
-    yymsp[0].minor.yy3->op = (u8)yymsp[-1].minor.yy328;
-    yymsp[0].minor.yy3->pPrior = yymsp[-2].minor.yy3;
+  if( yymsp[0].minor.yy387 ){
+    yymsp[0].minor.yy387->op = (u8)yymsp[-1].minor.yy4;
+    yymsp[0].minor.yy387->pPrior = yymsp[-2].minor.yy387;
   }else{
-    sqlite3SelectDelete(pParse->db, yymsp[-2].minor.yy3);
+    sqlite3SelectDelete(pParse->db, yymsp[-2].minor.yy387);
   }
-  yygotominor.yy3 = yymsp[0].minor.yy3;
+  yygotominor.yy387 = yymsp[0].minor.yy387;
 }
         break;
       case 116: /* multiselect_op ::= UNION ALL */
-{yygotominor.yy328 = TK_ALL;}
+{yygotominor.yy4 = TK_ALL;}
         break;
       case 118: /* oneselect ::= SELECT distinct selcollist from where_opt groupby_opt having_opt orderby_opt limit_opt */
 {
-  yygotominor.yy3 = sqlite3SelectNew(pParse,yymsp[-6].minor.yy14,yymsp[-5].minor.yy65,yymsp[-4].minor.yy132,yymsp[-3].minor.yy14,yymsp[-2].minor.yy132,yymsp[-1].minor.yy14,yymsp[-7].minor.yy328,yymsp[0].minor.yy476.pLimit,yymsp[0].minor.yy476.pOffset);
+  yygotominor.yy387 = sqlite3SelectNew(pParse,yymsp[-6].minor.yy322,yymsp[-5].minor.yy259,yymsp[-4].minor.yy314,yymsp[-3].minor.yy322,yymsp[-2].minor.yy314,yymsp[-1].minor.yy322,yymsp[-7].minor.yy4,yymsp[0].minor.yy292.pLimit,yymsp[0].minor.yy292.pOffset);
 }
         break;
       case 122: /* sclp ::= selcollist COMMA */
-      case 248: /* idxlist_opt ::= LP idxlist RP */ yytestcase(yyruleno==248);
-{yygotominor.yy14 = yymsp[-1].minor.yy14;}
+      case 247: /* idxlist_opt ::= LP idxlist RP */ yytestcase(yyruleno==247);
+{yygotominor.yy322 = yymsp[-1].minor.yy322;}
         break;
       case 123: /* sclp ::= */
       case 151: /* orderby_opt ::= */ yytestcase(yyruleno==151);
       case 159: /* groupby_opt ::= */ yytestcase(yyruleno==159);
-      case 241: /* exprlist ::= */ yytestcase(yyruleno==241);
-      case 247: /* idxlist_opt ::= */ yytestcase(yyruleno==247);
-{yygotominor.yy14 = 0;}
+      case 240: /* exprlist ::= */ yytestcase(yyruleno==240);
+      case 246: /* idxlist_opt ::= */ yytestcase(yyruleno==246);
+{yygotominor.yy322 = 0;}
         break;
       case 124: /* selcollist ::= sclp expr as */
 {
-   yygotominor.yy14 = sqlite3ExprListAppend(pParse, yymsp[-2].minor.yy14, yymsp[-1].minor.yy346.pExpr);
-   if( yymsp[0].minor.yy0.n>0 ) sqlite3ExprListSetName(pParse, yygotominor.yy14, &yymsp[0].minor.yy0, 1);
-   sqlite3ExprListSetSpan(pParse,yygotominor.yy14,&yymsp[-1].minor.yy346);
+   yygotominor.yy322 = sqlite3ExprListAppend(pParse, yymsp[-2].minor.yy322, yymsp[-1].minor.yy118.pExpr);
+   if( yymsp[0].minor.yy0.n>0 ) sqlite3ExprListSetName(pParse, yygotominor.yy322, &yymsp[0].minor.yy0, 1);
+   sqlite3ExprListSetSpan(pParse,yygotominor.yy322,&yymsp[-1].minor.yy118);
 }
         break;
       case 125: /* selcollist ::= sclp STAR */
 {
   Expr *p = sqlite3Expr(pParse->db, TK_ALL, 0);
-  yygotominor.yy14 = sqlite3ExprListAppend(pParse, yymsp[-1].minor.yy14, p);
+  yygotominor.yy322 = sqlite3ExprListAppend(pParse, yymsp[-1].minor.yy322, p);
 }
         break;
       case 126: /* selcollist ::= sclp nm DOT STAR */
@@ -99931,50 +101752,50 @@
   Expr *pRight = sqlite3PExpr(pParse, TK_ALL, 0, 0, &yymsp[0].minor.yy0);
   Expr *pLeft = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[-2].minor.yy0);
   Expr *pDot = sqlite3PExpr(pParse, TK_DOT, pLeft, pRight, 0);
-  yygotominor.yy14 = sqlite3ExprListAppend(pParse,yymsp[-3].minor.yy14, pDot);
+  yygotominor.yy322 = sqlite3ExprListAppend(pParse,yymsp[-3].minor.yy322, pDot);
 }
         break;
       case 129: /* as ::= */
 {yygotominor.yy0.n = 0;}
         break;
       case 130: /* from ::= */
-{yygotominor.yy65 = sqlite3DbMallocZero(pParse->db, sizeof(*yygotominor.yy65));}
+{yygotominor.yy259 = sqlite3DbMallocZero(pParse->db, sizeof(*yygotominor.yy259));}
         break;
       case 131: /* from ::= FROM seltablist */
 {
-  yygotominor.yy65 = yymsp[0].minor.yy65;
-  sqlite3SrcListShiftJoinType(yygotominor.yy65);
+  yygotominor.yy259 = yymsp[0].minor.yy259;
+  sqlite3SrcListShiftJoinType(yygotominor.yy259);
 }
         break;
       case 132: /* stl_prefix ::= seltablist joinop */
 {
-   yygotominor.yy65 = yymsp[-1].minor.yy65;
-   if( ALWAYS(yygotominor.yy65 && yygotominor.yy65->nSrc>0) ) yygotominor.yy65->a[yygotominor.yy65->nSrc-1].jointype = (u8)yymsp[0].minor.yy328;
+   yygotominor.yy259 = yymsp[-1].minor.yy259;
+   if( ALWAYS(yygotominor.yy259 && yygotominor.yy259->nSrc>0) ) yygotominor.yy259->a[yygotominor.yy259->nSrc-1].jointype = (u8)yymsp[0].minor.yy4;
 }
         break;
       case 133: /* stl_prefix ::= */
-{yygotominor.yy65 = 0;}
+{yygotominor.yy259 = 0;}
         break;
       case 134: /* seltablist ::= stl_prefix nm dbnm as indexed_opt on_opt using_opt */
 {
-  yygotominor.yy65 = sqlite3SrcListAppendFromTerm(pParse,yymsp[-6].minor.yy65,&yymsp[-5].minor.yy0,&yymsp[-4].minor.yy0,&yymsp[-3].minor.yy0,0,yymsp[-1].minor.yy132,yymsp[0].minor.yy408);
-  sqlite3SrcListIndexedBy(pParse, yygotominor.yy65, &yymsp[-2].minor.yy0);
+  yygotominor.yy259 = sqlite3SrcListAppendFromTerm(pParse,yymsp[-6].minor.yy259,&yymsp[-5].minor.yy0,&yymsp[-4].minor.yy0,&yymsp[-3].minor.yy0,0,yymsp[-1].minor.yy314,yymsp[0].minor.yy384);
+  sqlite3SrcListIndexedBy(pParse, yygotominor.yy259, &yymsp[-2].minor.yy0);
 }
         break;
       case 135: /* seltablist ::= stl_prefix LP select RP as on_opt using_opt */
 {
-    yygotominor.yy65 = sqlite3SrcListAppendFromTerm(pParse,yymsp[-6].minor.yy65,0,0,&yymsp[-2].minor.yy0,yymsp[-4].minor.yy3,yymsp[-1].minor.yy132,yymsp[0].minor.yy408);
+    yygotominor.yy259 = sqlite3SrcListAppendFromTerm(pParse,yymsp[-6].minor.yy259,0,0,&yymsp[-2].minor.yy0,yymsp[-4].minor.yy387,yymsp[-1].minor.yy314,yymsp[0].minor.yy384);
   }
         break;
       case 136: /* seltablist ::= stl_prefix LP seltablist RP as on_opt using_opt */
 {
-    if( yymsp[-6].minor.yy65==0 && yymsp[-2].minor.yy0.n==0 && yymsp[-1].minor.yy132==0 && yymsp[0].minor.yy408==0 ){
-      yygotominor.yy65 = yymsp[-4].minor.yy65;
+    if( yymsp[-6].minor.yy259==0 && yymsp[-2].minor.yy0.n==0 && yymsp[-1].minor.yy314==0 && yymsp[0].minor.yy384==0 ){
+      yygotominor.yy259 = yymsp[-4].minor.yy259;
     }else{
       Select *pSubquery;
-      sqlite3SrcListShiftJoinType(yymsp[-4].minor.yy65);
-      pSubquery = sqlite3SelectNew(pParse,0,yymsp[-4].minor.yy65,0,0,0,0,0,0,0);
-      yygotominor.yy65 = sqlite3SrcListAppendFromTerm(pParse,yymsp[-6].minor.yy65,0,0,&yymsp[-2].minor.yy0,pSubquery,yymsp[-1].minor.yy132,yymsp[0].minor.yy408);
+      sqlite3SrcListShiftJoinType(yymsp[-4].minor.yy259);
+      pSubquery = sqlite3SelectNew(pParse,0,yymsp[-4].minor.yy259,0,0,0,0,0,0,0);
+      yygotominor.yy259 = sqlite3SrcListAppendFromTerm(pParse,yymsp[-6].minor.yy259,0,0,&yymsp[-2].minor.yy0,pSubquery,yymsp[-1].minor.yy314,yymsp[0].minor.yy384);
     }
   }
         break;
@@ -99983,158 +101804,157 @@
 {yygotominor.yy0.z=0; yygotominor.yy0.n=0;}
         break;
       case 139: /* fullname ::= nm dbnm */
-{yygotominor.yy65 = sqlite3SrcListAppend(pParse->db,0,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy0);}
+{yygotominor.yy259 = sqlite3SrcListAppend(pParse->db,0,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy0);}
         break;
       case 140: /* joinop ::= COMMA|JOIN */
-{ yygotominor.yy328 = JT_INNER; }
+{ yygotominor.yy4 = JT_INNER; }
         break;
       case 141: /* joinop ::= JOIN_KW JOIN */
-{ yygotominor.yy328 = sqlite3JoinType(pParse,&yymsp[-1].minor.yy0,0,0); }
+{ yygotominor.yy4 = sqlite3JoinType(pParse,&yymsp[-1].minor.yy0,0,0); }
         break;
       case 142: /* joinop ::= JOIN_KW nm JOIN */
-{ yygotominor.yy328 = sqlite3JoinType(pParse,&yymsp[-2].minor.yy0,&yymsp[-1].minor.yy0,0); }
+{ yygotominor.yy4 = sqlite3JoinType(pParse,&yymsp[-2].minor.yy0,&yymsp[-1].minor.yy0,0); }
         break;
       case 143: /* joinop ::= JOIN_KW nm nm JOIN */
-{ yygotominor.yy328 = sqlite3JoinType(pParse,&yymsp[-3].minor.yy0,&yymsp[-2].minor.yy0,&yymsp[-1].minor.yy0); }
+{ yygotominor.yy4 = sqlite3JoinType(pParse,&yymsp[-3].minor.yy0,&yymsp[-2].minor.yy0,&yymsp[-1].minor.yy0); }
         break;
       case 144: /* on_opt ::= ON expr */
       case 155: /* sortitem ::= expr */ yytestcase(yyruleno==155);
       case 162: /* having_opt ::= HAVING expr */ yytestcase(yyruleno==162);
       case 169: /* where_opt ::= WHERE expr */ yytestcase(yyruleno==169);
-      case 236: /* case_else ::= ELSE expr */ yytestcase(yyruleno==236);
-      case 238: /* case_operand ::= expr */ yytestcase(yyruleno==238);
-{yygotominor.yy132 = yymsp[0].minor.yy346.pExpr;}
+      case 235: /* case_else ::= ELSE expr */ yytestcase(yyruleno==235);
+      case 237: /* case_operand ::= expr */ yytestcase(yyruleno==237);
+{yygotominor.yy314 = yymsp[0].minor.yy118.pExpr;}
         break;
       case 145: /* on_opt ::= */
       case 161: /* having_opt ::= */ yytestcase(yyruleno==161);
       case 168: /* where_opt ::= */ yytestcase(yyruleno==168);
-      case 237: /* case_else ::= */ yytestcase(yyruleno==237);
-      case 239: /* case_operand ::= */ yytestcase(yyruleno==239);
-{yygotominor.yy132 = 0;}
+      case 236: /* case_else ::= */ yytestcase(yyruleno==236);
+      case 238: /* case_operand ::= */ yytestcase(yyruleno==238);
+{yygotominor.yy314 = 0;}
         break;
       case 148: /* indexed_opt ::= NOT INDEXED */
 {yygotominor.yy0.z=0; yygotominor.yy0.n=1;}
         break;
       case 149: /* using_opt ::= USING LP inscollist RP */
       case 181: /* inscollist_opt ::= LP inscollist RP */ yytestcase(yyruleno==181);
-{yygotominor.yy408 = yymsp[-1].minor.yy408;}
+{yygotominor.yy384 = yymsp[-1].minor.yy384;}
         break;
       case 150: /* using_opt ::= */
       case 180: /* inscollist_opt ::= */ yytestcase(yyruleno==180);
-{yygotominor.yy408 = 0;}
+{yygotominor.yy384 = 0;}
         break;
       case 152: /* orderby_opt ::= ORDER BY sortlist */
       case 160: /* groupby_opt ::= GROUP BY nexprlist */ yytestcase(yyruleno==160);
-      case 240: /* exprlist ::= nexprlist */ yytestcase(yyruleno==240);
-{yygotominor.yy14 = yymsp[0].minor.yy14;}
+      case 239: /* exprlist ::= nexprlist */ yytestcase(yyruleno==239);
+{yygotominor.yy322 = yymsp[0].minor.yy322;}
         break;
       case 153: /* sortlist ::= sortlist COMMA sortitem sortorder */
 {
-  yygotominor.yy14 = sqlite3ExprListAppend(pParse,yymsp[-3].minor.yy14,yymsp[-1].minor.yy132);
-  if( yygotominor.yy14 ) yygotominor.yy14->a[yygotominor.yy14->nExpr-1].sortOrder = (u8)yymsp[0].minor.yy328;
+  yygotominor.yy322 = sqlite3ExprListAppend(pParse,yymsp[-3].minor.yy322,yymsp[-1].minor.yy314);
+  if( yygotominor.yy322 ) yygotominor.yy322->a[yygotominor.yy322->nExpr-1].sortOrder = (u8)yymsp[0].minor.yy4;
 }
         break;
       case 154: /* sortlist ::= sortitem sortorder */
 {
-  yygotominor.yy14 = sqlite3ExprListAppend(pParse,0,yymsp[-1].minor.yy132);
-  if( yygotominor.yy14 && ALWAYS(yygotominor.yy14->a) ) yygotominor.yy14->a[0].sortOrder = (u8)yymsp[0].minor.yy328;
+  yygotominor.yy322 = sqlite3ExprListAppend(pParse,0,yymsp[-1].minor.yy314);
+  if( yygotominor.yy322 && ALWAYS(yygotominor.yy322->a) ) yygotominor.yy322->a[0].sortOrder = (u8)yymsp[0].minor.yy4;
 }
         break;
       case 156: /* sortorder ::= ASC */
       case 158: /* sortorder ::= */ yytestcase(yyruleno==158);
-{yygotominor.yy328 = SQLITE_SO_ASC;}
+{yygotominor.yy4 = SQLITE_SO_ASC;}
         break;
       case 157: /* sortorder ::= DESC */
-{yygotominor.yy328 = SQLITE_SO_DESC;}
+{yygotominor.yy4 = SQLITE_SO_DESC;}
         break;
       case 163: /* limit_opt ::= */
-{yygotominor.yy476.pLimit = 0; yygotominor.yy476.pOffset = 0;}
+{yygotominor.yy292.pLimit = 0; yygotominor.yy292.pOffset = 0;}
         break;
       case 164: /* limit_opt ::= LIMIT expr */
-{yygotominor.yy476.pLimit = yymsp[0].minor.yy346.pExpr; yygotominor.yy476.pOffset = 0;}
+{yygotominor.yy292.pLimit = yymsp[0].minor.yy118.pExpr; yygotominor.yy292.pOffset = 0;}
         break;
       case 165: /* limit_opt ::= LIMIT expr OFFSET expr */
-{yygotominor.yy476.pLimit = yymsp[-2].minor.yy346.pExpr; yygotominor.yy476.pOffset = yymsp[0].minor.yy346.pExpr;}
+{yygotominor.yy292.pLimit = yymsp[-2].minor.yy118.pExpr; yygotominor.yy292.pOffset = yymsp[0].minor.yy118.pExpr;}
         break;
       case 166: /* limit_opt ::= LIMIT expr COMMA expr */
-{yygotominor.yy476.pOffset = yymsp[-2].minor.yy346.pExpr; yygotominor.yy476.pLimit = yymsp[0].minor.yy346.pExpr;}
+{yygotominor.yy292.pOffset = yymsp[-2].minor.yy118.pExpr; yygotominor.yy292.pLimit = yymsp[0].minor.yy118.pExpr;}
         break;
       case 167: /* cmd ::= DELETE FROM fullname indexed_opt where_opt */
 {
-  sqlite3SrcListIndexedBy(pParse, yymsp[-2].minor.yy65, &yymsp[-1].minor.yy0);
-  sqlite3DeleteFrom(pParse,yymsp[-2].minor.yy65,yymsp[0].minor.yy132);
+  sqlite3SrcListIndexedBy(pParse, yymsp[-2].minor.yy259, &yymsp[-1].minor.yy0);
+  sqlite3DeleteFrom(pParse,yymsp[-2].minor.yy259,yymsp[0].minor.yy314);
 }
         break;
       case 170: /* cmd ::= UPDATE orconf fullname indexed_opt SET setlist where_opt */
 {
-  sqlite3SrcListIndexedBy(pParse, yymsp[-4].minor.yy65, &yymsp[-3].minor.yy0);
-  sqlite3ExprListCheckLength(pParse,yymsp[-1].minor.yy14,"set list"); 
-  sqlite3Update(pParse,yymsp[-4].minor.yy65,yymsp[-1].minor.yy14,yymsp[0].minor.yy132,yymsp[-5].minor.yy186);
+  sqlite3SrcListIndexedBy(pParse, yymsp[-4].minor.yy259, &yymsp[-3].minor.yy0);
+  sqlite3ExprListCheckLength(pParse,yymsp[-1].minor.yy322,"set list"); 
+  sqlite3Update(pParse,yymsp[-4].minor.yy259,yymsp[-1].minor.yy322,yymsp[0].minor.yy314,yymsp[-5].minor.yy210);
 }
         break;
       case 171: /* setlist ::= setlist COMMA nm EQ expr */
 {
-  yygotominor.yy14 = sqlite3ExprListAppend(pParse, yymsp[-4].minor.yy14, yymsp[0].minor.yy346.pExpr);
-  sqlite3ExprListSetName(pParse, yygotominor.yy14, &yymsp[-2].minor.yy0, 1);
+  yygotominor.yy322 = sqlite3ExprListAppend(pParse, yymsp[-4].minor.yy322, yymsp[0].minor.yy118.pExpr);
+  sqlite3ExprListSetName(pParse, yygotominor.yy322, &yymsp[-2].minor.yy0, 1);
 }
         break;
       case 172: /* setlist ::= nm EQ expr */
 {
-  yygotominor.yy14 = sqlite3ExprListAppend(pParse, 0, yymsp[0].minor.yy346.pExpr);
-  sqlite3ExprListSetName(pParse, yygotominor.yy14, &yymsp[-2].minor.yy0, 1);
+  yygotominor.yy322 = sqlite3ExprListAppend(pParse, 0, yymsp[0].minor.yy118.pExpr);
+  sqlite3ExprListSetName(pParse, yygotominor.yy322, &yymsp[-2].minor.yy0, 1);
 }
         break;
       case 173: /* cmd ::= insert_cmd INTO fullname inscollist_opt VALUES LP itemlist RP */
-{sqlite3Insert(pParse, yymsp[-5].minor.yy65, yymsp[-1].minor.yy14, 0, yymsp[-4].minor.yy408, yymsp[-7].minor.yy186);}
+{sqlite3Insert(pParse, yymsp[-5].minor.yy259, yymsp[-1].minor.yy322, 0, yymsp[-4].minor.yy384, yymsp[-7].minor.yy210);}
         break;
       case 174: /* cmd ::= insert_cmd INTO fullname inscollist_opt select */
-{sqlite3Insert(pParse, yymsp[-2].minor.yy65, 0, yymsp[0].minor.yy3, yymsp[-1].minor.yy408, yymsp[-4].minor.yy186);}
+{sqlite3Insert(pParse, yymsp[-2].minor.yy259, 0, yymsp[0].minor.yy387, yymsp[-1].minor.yy384, yymsp[-4].minor.yy210);}
         break;
       case 175: /* cmd ::= insert_cmd INTO fullname inscollist_opt DEFAULT VALUES */
-{sqlite3Insert(pParse, yymsp[-3].minor.yy65, 0, 0, yymsp[-2].minor.yy408, yymsp[-5].minor.yy186);}
+{sqlite3Insert(pParse, yymsp[-3].minor.yy259, 0, 0, yymsp[-2].minor.yy384, yymsp[-5].minor.yy210);}
         break;
       case 176: /* insert_cmd ::= INSERT orconf */
-{yygotominor.yy186 = yymsp[0].minor.yy186;}
+{yygotominor.yy210 = yymsp[0].minor.yy210;}
         break;
       case 177: /* insert_cmd ::= REPLACE */
-{yygotominor.yy186 = OE_Replace;}
+{yygotominor.yy210 = OE_Replace;}
         break;
       case 178: /* itemlist ::= itemlist COMMA expr */
-      case 242: /* nexprlist ::= nexprlist COMMA expr */ yytestcase(yyruleno==242);
-{yygotominor.yy14 = sqlite3ExprListAppend(pParse,yymsp[-2].minor.yy14,yymsp[0].minor.yy346.pExpr);}
+      case 241: /* nexprlist ::= nexprlist COMMA expr */ yytestcase(yyruleno==241);
+{yygotominor.yy322 = sqlite3ExprListAppend(pParse,yymsp[-2].minor.yy322,yymsp[0].minor.yy118.pExpr);}
         break;
       case 179: /* itemlist ::= expr */
-      case 243: /* nexprlist ::= expr */ yytestcase(yyruleno==243);
-{yygotominor.yy14 = sqlite3ExprListAppend(pParse,0,yymsp[0].minor.yy346.pExpr);}
+      case 242: /* nexprlist ::= expr */ yytestcase(yyruleno==242);
+{yygotominor.yy322 = sqlite3ExprListAppend(pParse,0,yymsp[0].minor.yy118.pExpr);}
         break;
       case 182: /* inscollist ::= inscollist COMMA nm */
-{yygotominor.yy408 = sqlite3IdListAppend(pParse->db,yymsp[-2].minor.yy408,&yymsp[0].minor.yy0);}
+{yygotominor.yy384 = sqlite3IdListAppend(pParse->db,yymsp[-2].minor.yy384,&yymsp[0].minor.yy0);}
         break;
       case 183: /* inscollist ::= nm */
-{yygotominor.yy408 = sqlite3IdListAppend(pParse->db,0,&yymsp[0].minor.yy0);}
+{yygotominor.yy384 = sqlite3IdListAppend(pParse->db,0,&yymsp[0].minor.yy0);}
         break;
       case 184: /* expr ::= term */
-      case 212: /* escape ::= ESCAPE expr */ yytestcase(yyruleno==212);
-{yygotominor.yy346 = yymsp[0].minor.yy346;}
+{yygotominor.yy118 = yymsp[0].minor.yy118;}
         break;
       case 185: /* expr ::= LP expr RP */
-{yygotominor.yy346.pExpr = yymsp[-1].minor.yy346.pExpr; spanSet(&yygotominor.yy346,&yymsp[-2].minor.yy0,&yymsp[0].minor.yy0);}
+{yygotominor.yy118.pExpr = yymsp[-1].minor.yy118.pExpr; spanSet(&yygotominor.yy118,&yymsp[-2].minor.yy0,&yymsp[0].minor.yy0);}
         break;
       case 186: /* term ::= NULL */
       case 191: /* term ::= INTEGER|FLOAT|BLOB */ yytestcase(yyruleno==191);
       case 192: /* term ::= STRING */ yytestcase(yyruleno==192);
-{spanExpr(&yygotominor.yy346, pParse, yymsp[0].major, &yymsp[0].minor.yy0);}
+{spanExpr(&yygotominor.yy118, pParse, yymsp[0].major, &yymsp[0].minor.yy0);}
         break;
       case 187: /* expr ::= id */
       case 188: /* expr ::= JOIN_KW */ yytestcase(yyruleno==188);
-{spanExpr(&yygotominor.yy346, pParse, TK_ID, &yymsp[0].minor.yy0);}
+{spanExpr(&yygotominor.yy118, pParse, TK_ID, &yymsp[0].minor.yy0);}
         break;
       case 189: /* expr ::= nm DOT nm */
 {
   Expr *temp1 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[-2].minor.yy0);
   Expr *temp2 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[0].minor.yy0);
-  yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_DOT, temp1, temp2, 0);
-  spanSet(&yygotominor.yy346,&yymsp[-2].minor.yy0,&yymsp[0].minor.yy0);
+  yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_DOT, temp1, temp2, 0);
+  spanSet(&yygotominor.yy118,&yymsp[-2].minor.yy0,&yymsp[0].minor.yy0);
 }
         break;
       case 190: /* expr ::= nm DOT nm DOT nm */
@@ -100143,8 +101963,8 @@
   Expr *temp2 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[-2].minor.yy0);
   Expr *temp3 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[0].minor.yy0);
   Expr *temp4 = sqlite3PExpr(pParse, TK_DOT, temp2, temp3, 0);
-  yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_DOT, temp1, temp4, 0);
-  spanSet(&yygotominor.yy346,&yymsp[-4].minor.yy0,&yymsp[0].minor.yy0);
+  yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_DOT, temp1, temp4, 0);
+  spanSet(&yygotominor.yy118,&yymsp[-4].minor.yy0,&yymsp[0].minor.yy0);
 }
         break;
       case 193: /* expr ::= REGISTER */
@@ -100154,61 +101974,61 @@
   ** in the virtual machine.  #N is the N-th register. */
   if( pParse->nested==0 ){
     sqlite3ErrorMsg(pParse, "near \"%T\": syntax error", &yymsp[0].minor.yy0);
-    yygotominor.yy346.pExpr = 0;
+    yygotominor.yy118.pExpr = 0;
   }else{
-    yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_REGISTER, 0, 0, &yymsp[0].minor.yy0);
-    if( yygotominor.yy346.pExpr ) sqlite3GetInt32(&yymsp[0].minor.yy0.z[1], &yygotominor.yy346.pExpr->iTable);
+    yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_REGISTER, 0, 0, &yymsp[0].minor.yy0);
+    if( yygotominor.yy118.pExpr ) sqlite3GetInt32(&yymsp[0].minor.yy0.z[1], &yygotominor.yy118.pExpr->iTable);
   }
-  spanSet(&yygotominor.yy346, &yymsp[0].minor.yy0, &yymsp[0].minor.yy0);
+  spanSet(&yygotominor.yy118, &yymsp[0].minor.yy0, &yymsp[0].minor.yy0);
 }
         break;
       case 194: /* expr ::= VARIABLE */
 {
-  spanExpr(&yygotominor.yy346, pParse, TK_VARIABLE, &yymsp[0].minor.yy0);
-  sqlite3ExprAssignVarNumber(pParse, yygotominor.yy346.pExpr);
-  spanSet(&yygotominor.yy346, &yymsp[0].minor.yy0, &yymsp[0].minor.yy0);
+  spanExpr(&yygotominor.yy118, pParse, TK_VARIABLE, &yymsp[0].minor.yy0);
+  sqlite3ExprAssignVarNumber(pParse, yygotominor.yy118.pExpr);
+  spanSet(&yygotominor.yy118, &yymsp[0].minor.yy0, &yymsp[0].minor.yy0);
 }
         break;
       case 195: /* expr ::= expr COLLATE ids */
 {
-  yygotominor.yy346.pExpr = sqlite3ExprSetColl(pParse, yymsp[-2].minor.yy346.pExpr, &yymsp[0].minor.yy0);
-  yygotominor.yy346.zStart = yymsp[-2].minor.yy346.zStart;
-  yygotominor.yy346.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
+  yygotominor.yy118.pExpr = sqlite3ExprSetCollByToken(pParse, yymsp[-2].minor.yy118.pExpr, &yymsp[0].minor.yy0);
+  yygotominor.yy118.zStart = yymsp[-2].minor.yy118.zStart;
+  yygotominor.yy118.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
 }
         break;
       case 196: /* expr ::= CAST LP expr AS typetoken RP */
 {
-  yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_CAST, yymsp[-3].minor.yy346.pExpr, 0, &yymsp[-1].minor.yy0);
-  spanSet(&yygotominor.yy346,&yymsp[-5].minor.yy0,&yymsp[0].minor.yy0);
+  yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_CAST, yymsp[-3].minor.yy118.pExpr, 0, &yymsp[-1].minor.yy0);
+  spanSet(&yygotominor.yy118,&yymsp[-5].minor.yy0,&yymsp[0].minor.yy0);
 }
         break;
       case 197: /* expr ::= ID LP distinct exprlist RP */
 {
-  if( yymsp[-1].minor.yy14 && yymsp[-1].minor.yy14->nExpr>pParse->db->aLimit[SQLITE_LIMIT_FUNCTION_ARG] ){
+  if( yymsp[-1].minor.yy322 && yymsp[-1].minor.yy322->nExpr>pParse->db->aLimit[SQLITE_LIMIT_FUNCTION_ARG] ){
     sqlite3ErrorMsg(pParse, "too many arguments on function %T", &yymsp[-4].minor.yy0);
   }
-  yygotominor.yy346.pExpr = sqlite3ExprFunction(pParse, yymsp[-1].minor.yy14, &yymsp[-4].minor.yy0);
-  spanSet(&yygotominor.yy346,&yymsp[-4].minor.yy0,&yymsp[0].minor.yy0);
-  if( yymsp[-2].minor.yy328 && yygotominor.yy346.pExpr ){
-    yygotominor.yy346.pExpr->flags |= EP_Distinct;
+  yygotominor.yy118.pExpr = sqlite3ExprFunction(pParse, yymsp[-1].minor.yy322, &yymsp[-4].minor.yy0);
+  spanSet(&yygotominor.yy118,&yymsp[-4].minor.yy0,&yymsp[0].minor.yy0);
+  if( yymsp[-2].minor.yy4 && yygotominor.yy118.pExpr ){
+    yygotominor.yy118.pExpr->flags |= EP_Distinct;
   }
 }
         break;
       case 198: /* expr ::= ID LP STAR RP */
 {
-  yygotominor.yy346.pExpr = sqlite3ExprFunction(pParse, 0, &yymsp[-3].minor.yy0);
-  spanSet(&yygotominor.yy346,&yymsp[-3].minor.yy0,&yymsp[0].minor.yy0);
+  yygotominor.yy118.pExpr = sqlite3ExprFunction(pParse, 0, &yymsp[-3].minor.yy0);
+  spanSet(&yygotominor.yy118,&yymsp[-3].minor.yy0,&yymsp[0].minor.yy0);
 }
         break;
       case 199: /* term ::= CTIME_KW */
 {
   /* The CURRENT_TIME, CURRENT_DATE, and CURRENT_TIMESTAMP values are
   ** treated as functions that return constants */
-  yygotominor.yy346.pExpr = sqlite3ExprFunction(pParse, 0,&yymsp[0].minor.yy0);
-  if( yygotominor.yy346.pExpr ){
-    yygotominor.yy346.pExpr->op = TK_CONST_FUNC;  
+  yygotominor.yy118.pExpr = sqlite3ExprFunction(pParse, 0,&yymsp[0].minor.yy0);
+  if( yygotominor.yy118.pExpr ){
+    yygotominor.yy118.pExpr->op = TK_CONST_FUNC;  
   }
-  spanSet(&yygotominor.yy346, &yymsp[0].minor.yy0, &yymsp[0].minor.yy0);
+  spanSet(&yygotominor.yy118, &yymsp[0].minor.yy0, &yymsp[0].minor.yy0);
 }
         break;
       case 200: /* expr ::= expr AND expr */
@@ -100219,295 +102039,315 @@
       case 205: /* expr ::= expr PLUS|MINUS expr */ yytestcase(yyruleno==205);
       case 206: /* expr ::= expr STAR|SLASH|REM expr */ yytestcase(yyruleno==206);
       case 207: /* expr ::= expr CONCAT expr */ yytestcase(yyruleno==207);
-{spanBinaryExpr(&yygotominor.yy346,pParse,yymsp[-1].major,&yymsp[-2].minor.yy346,&yymsp[0].minor.yy346);}
+{spanBinaryExpr(&yygotominor.yy118,pParse,yymsp[-1].major,&yymsp[-2].minor.yy118,&yymsp[0].minor.yy118);}
         break;
       case 208: /* likeop ::= LIKE_KW */
       case 210: /* likeop ::= MATCH */ yytestcase(yyruleno==210);
-{yygotominor.yy96.eOperator = yymsp[0].minor.yy0; yygotominor.yy96.not = 0;}
+{yygotominor.yy342.eOperator = yymsp[0].minor.yy0; yygotominor.yy342.not = 0;}
         break;
       case 209: /* likeop ::= NOT LIKE_KW */
       case 211: /* likeop ::= NOT MATCH */ yytestcase(yyruleno==211);
-{yygotominor.yy96.eOperator = yymsp[0].minor.yy0; yygotominor.yy96.not = 1;}
+{yygotominor.yy342.eOperator = yymsp[0].minor.yy0; yygotominor.yy342.not = 1;}
         break;
-      case 213: /* escape ::= */
-{memset(&yygotominor.yy346,0,sizeof(yygotominor.yy346));}
-        break;
-      case 214: /* expr ::= expr likeop expr escape */
+      case 212: /* expr ::= expr likeop expr */
 {
   ExprList *pList;
-  pList = sqlite3ExprListAppend(pParse,0, yymsp[-1].minor.yy346.pExpr);
-  pList = sqlite3ExprListAppend(pParse,pList, yymsp[-3].minor.yy346.pExpr);
-  if( yymsp[0].minor.yy346.pExpr ){
-    pList = sqlite3ExprListAppend(pParse,pList, yymsp[0].minor.yy346.pExpr);
-  }
-  yygotominor.yy346.pExpr = sqlite3ExprFunction(pParse, pList, &yymsp[-2].minor.yy96.eOperator);
-  if( yymsp[-2].minor.yy96.not ) yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy346.pExpr, 0, 0);
-  yygotominor.yy346.zStart = yymsp[-3].minor.yy346.zStart;
-  yygotominor.yy346.zEnd = yymsp[-1].minor.yy346.zEnd;
-  if( yygotominor.yy346.pExpr ) yygotominor.yy346.pExpr->flags |= EP_InfixFunc;
+  pList = sqlite3ExprListAppend(pParse,0, yymsp[0].minor.yy118.pExpr);
+  pList = sqlite3ExprListAppend(pParse,pList, yymsp[-2].minor.yy118.pExpr);
+  yygotominor.yy118.pExpr = sqlite3ExprFunction(pParse, pList, &yymsp[-1].minor.yy342.eOperator);
+  if( yymsp[-1].minor.yy342.not ) yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy118.pExpr, 0, 0);
+  yygotominor.yy118.zStart = yymsp[-2].minor.yy118.zStart;
+  yygotominor.yy118.zEnd = yymsp[0].minor.yy118.zEnd;
+  if( yygotominor.yy118.pExpr ) yygotominor.yy118.pExpr->flags |= EP_InfixFunc;
 }
         break;
-      case 215: /* expr ::= expr ISNULL|NOTNULL */
-{spanUnaryPostfix(&yygotominor.yy346,pParse,yymsp[0].major,&yymsp[-1].minor.yy346,&yymsp[0].minor.yy0);}
-        break;
-      case 216: /* expr ::= expr NOT NULL */
-{spanUnaryPostfix(&yygotominor.yy346,pParse,TK_NOTNULL,&yymsp[-2].minor.yy346,&yymsp[0].minor.yy0);}
-        break;
-      case 217: /* expr ::= expr IS expr */
+      case 213: /* expr ::= expr likeop expr ESCAPE expr */
 {
-  spanBinaryExpr(&yygotominor.yy346,pParse,TK_IS,&yymsp[-2].minor.yy346,&yymsp[0].minor.yy346);
-  binaryToUnaryIfNull(pParse, yymsp[0].minor.yy346.pExpr, yygotominor.yy346.pExpr, TK_ISNULL);
+  ExprList *pList;
+  pList = sqlite3ExprListAppend(pParse,0, yymsp[-2].minor.yy118.pExpr);
+  pList = sqlite3ExprListAppend(pParse,pList, yymsp[-4].minor.yy118.pExpr);
+  pList = sqlite3ExprListAppend(pParse,pList, yymsp[0].minor.yy118.pExpr);
+  yygotominor.yy118.pExpr = sqlite3ExprFunction(pParse, pList, &yymsp[-3].minor.yy342.eOperator);
+  if( yymsp[-3].minor.yy342.not ) yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy118.pExpr, 0, 0);
+  yygotominor.yy118.zStart = yymsp[-4].minor.yy118.zStart;
+  yygotominor.yy118.zEnd = yymsp[0].minor.yy118.zEnd;
+  if( yygotominor.yy118.pExpr ) yygotominor.yy118.pExpr->flags |= EP_InfixFunc;
 }
         break;
-      case 218: /* expr ::= expr IS NOT expr */
+      case 214: /* expr ::= expr ISNULL|NOTNULL */
+{spanUnaryPostfix(&yygotominor.yy118,pParse,yymsp[0].major,&yymsp[-1].minor.yy118,&yymsp[0].minor.yy0);}
+        break;
+      case 215: /* expr ::= expr NOT NULL */
+{spanUnaryPostfix(&yygotominor.yy118,pParse,TK_NOTNULL,&yymsp[-2].minor.yy118,&yymsp[0].minor.yy0);}
+        break;
+      case 216: /* expr ::= expr IS expr */
 {
-  spanBinaryExpr(&yygotominor.yy346,pParse,TK_ISNOT,&yymsp[-3].minor.yy346,&yymsp[0].minor.yy346);
-  binaryToUnaryIfNull(pParse, yymsp[0].minor.yy346.pExpr, yygotominor.yy346.pExpr, TK_NOTNULL);
+  spanBinaryExpr(&yygotominor.yy118,pParse,TK_IS,&yymsp[-2].minor.yy118,&yymsp[0].minor.yy118);
+  binaryToUnaryIfNull(pParse, yymsp[0].minor.yy118.pExpr, yygotominor.yy118.pExpr, TK_ISNULL);
 }
         break;
-      case 219: /* expr ::= NOT expr */
-      case 220: /* expr ::= BITNOT expr */ yytestcase(yyruleno==220);
-{spanUnaryPrefix(&yygotominor.yy346,pParse,yymsp[-1].major,&yymsp[0].minor.yy346,&yymsp[-1].minor.yy0);}
-        break;
-      case 221: /* expr ::= MINUS expr */
-{spanUnaryPrefix(&yygotominor.yy346,pParse,TK_UMINUS,&yymsp[0].minor.yy346,&yymsp[-1].minor.yy0);}
-        break;
-      case 222: /* expr ::= PLUS expr */
-{spanUnaryPrefix(&yygotominor.yy346,pParse,TK_UPLUS,&yymsp[0].minor.yy346,&yymsp[-1].minor.yy0);}
-        break;
-      case 225: /* expr ::= expr between_op expr AND expr */
+      case 217: /* expr ::= expr IS NOT expr */
 {
-  ExprList *pList = sqlite3ExprListAppend(pParse,0, yymsp[-2].minor.yy346.pExpr);
-  pList = sqlite3ExprListAppend(pParse,pList, yymsp[0].minor.yy346.pExpr);
-  yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_BETWEEN, yymsp[-4].minor.yy346.pExpr, 0, 0);
-  if( yygotominor.yy346.pExpr ){
-    yygotominor.yy346.pExpr->x.pList = pList;
+  spanBinaryExpr(&yygotominor.yy118,pParse,TK_ISNOT,&yymsp[-3].minor.yy118,&yymsp[0].minor.yy118);
+  binaryToUnaryIfNull(pParse, yymsp[0].minor.yy118.pExpr, yygotominor.yy118.pExpr, TK_NOTNULL);
+}
+        break;
+      case 218: /* expr ::= NOT expr */
+      case 219: /* expr ::= BITNOT expr */ yytestcase(yyruleno==219);
+{spanUnaryPrefix(&yygotominor.yy118,pParse,yymsp[-1].major,&yymsp[0].minor.yy118,&yymsp[-1].minor.yy0);}
+        break;
+      case 220: /* expr ::= MINUS expr */
+{spanUnaryPrefix(&yygotominor.yy118,pParse,TK_UMINUS,&yymsp[0].minor.yy118,&yymsp[-1].minor.yy0);}
+        break;
+      case 221: /* expr ::= PLUS expr */
+{spanUnaryPrefix(&yygotominor.yy118,pParse,TK_UPLUS,&yymsp[0].minor.yy118,&yymsp[-1].minor.yy0);}
+        break;
+      case 224: /* expr ::= expr between_op expr AND expr */
+{
+  ExprList *pList = sqlite3ExprListAppend(pParse,0, yymsp[-2].minor.yy118.pExpr);
+  pList = sqlite3ExprListAppend(pParse,pList, yymsp[0].minor.yy118.pExpr);
+  yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_BETWEEN, yymsp[-4].minor.yy118.pExpr, 0, 0);
+  if( yygotominor.yy118.pExpr ){
+    yygotominor.yy118.pExpr->x.pList = pList;
   }else{
     sqlite3ExprListDelete(pParse->db, pList);
   } 
-  if( yymsp[-3].minor.yy328 ) yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy346.pExpr, 0, 0);
-  yygotominor.yy346.zStart = yymsp[-4].minor.yy346.zStart;
-  yygotominor.yy346.zEnd = yymsp[0].minor.yy346.zEnd;
+  if( yymsp[-3].minor.yy4 ) yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy118.pExpr, 0, 0);
+  yygotominor.yy118.zStart = yymsp[-4].minor.yy118.zStart;
+  yygotominor.yy118.zEnd = yymsp[0].minor.yy118.zEnd;
 }
         break;
-      case 228: /* expr ::= expr in_op LP exprlist RP */
+      case 227: /* expr ::= expr in_op LP exprlist RP */
 {
-    yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_IN, yymsp[-4].minor.yy346.pExpr, 0, 0);
-    if( yygotominor.yy346.pExpr ){
-      yygotominor.yy346.pExpr->x.pList = yymsp[-1].minor.yy14;
-      sqlite3ExprSetHeight(pParse, yygotominor.yy346.pExpr);
+    if( yymsp[-1].minor.yy322==0 ){
+      /* Expressions of the form
+      **
+      **      expr1 IN ()
+      **      expr1 NOT IN ()
+      **
+      ** simplify to constants 0 (false) and 1 (true), respectively,
+      ** regardless of the value of expr1.
+      */
+      yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_INTEGER, 0, 0, &sqlite3IntTokens[yymsp[-3].minor.yy4]);
+      sqlite3ExprDelete(pParse->db, yymsp[-4].minor.yy118.pExpr);
     }else{
-      sqlite3ExprListDelete(pParse->db, yymsp[-1].minor.yy14);
+      yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_IN, yymsp[-4].minor.yy118.pExpr, 0, 0);
+      if( yygotominor.yy118.pExpr ){
+        yygotominor.yy118.pExpr->x.pList = yymsp[-1].minor.yy322;
+        sqlite3ExprSetHeight(pParse, yygotominor.yy118.pExpr);
+      }else{
+        sqlite3ExprListDelete(pParse->db, yymsp[-1].minor.yy322);
+      }
+      if( yymsp[-3].minor.yy4 ) yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy118.pExpr, 0, 0);
     }
-    if( yymsp[-3].minor.yy328 ) yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy346.pExpr, 0, 0);
-    yygotominor.yy346.zStart = yymsp[-4].minor.yy346.zStart;
-    yygotominor.yy346.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
+    yygotominor.yy118.zStart = yymsp[-4].minor.yy118.zStart;
+    yygotominor.yy118.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
   }
         break;
-      case 229: /* expr ::= LP select RP */
+      case 228: /* expr ::= LP select RP */
 {
-    yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_SELECT, 0, 0, 0);
-    if( yygotominor.yy346.pExpr ){
-      yygotominor.yy346.pExpr->x.pSelect = yymsp[-1].minor.yy3;
-      ExprSetProperty(yygotominor.yy346.pExpr, EP_xIsSelect);
-      sqlite3ExprSetHeight(pParse, yygotominor.yy346.pExpr);
+    yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_SELECT, 0, 0, 0);
+    if( yygotominor.yy118.pExpr ){
+      yygotominor.yy118.pExpr->x.pSelect = yymsp[-1].minor.yy387;
+      ExprSetProperty(yygotominor.yy118.pExpr, EP_xIsSelect);
+      sqlite3ExprSetHeight(pParse, yygotominor.yy118.pExpr);
     }else{
-      sqlite3SelectDelete(pParse->db, yymsp[-1].minor.yy3);
+      sqlite3SelectDelete(pParse->db, yymsp[-1].minor.yy387);
     }
-    yygotominor.yy346.zStart = yymsp[-2].minor.yy0.z;
-    yygotominor.yy346.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
+    yygotominor.yy118.zStart = yymsp[-2].minor.yy0.z;
+    yygotominor.yy118.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
   }
         break;
-      case 230: /* expr ::= expr in_op LP select RP */
+      case 229: /* expr ::= expr in_op LP select RP */
 {
-    yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_IN, yymsp[-4].minor.yy346.pExpr, 0, 0);
-    if( yygotominor.yy346.pExpr ){
-      yygotominor.yy346.pExpr->x.pSelect = yymsp[-1].minor.yy3;
-      ExprSetProperty(yygotominor.yy346.pExpr, EP_xIsSelect);
-      sqlite3ExprSetHeight(pParse, yygotominor.yy346.pExpr);
+    yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_IN, yymsp[-4].minor.yy118.pExpr, 0, 0);
+    if( yygotominor.yy118.pExpr ){
+      yygotominor.yy118.pExpr->x.pSelect = yymsp[-1].minor.yy387;
+      ExprSetProperty(yygotominor.yy118.pExpr, EP_xIsSelect);
+      sqlite3ExprSetHeight(pParse, yygotominor.yy118.pExpr);
     }else{
-      sqlite3SelectDelete(pParse->db, yymsp[-1].minor.yy3);
+      sqlite3SelectDelete(pParse->db, yymsp[-1].minor.yy387);
     }
-    if( yymsp[-3].minor.yy328 ) yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy346.pExpr, 0, 0);
-    yygotominor.yy346.zStart = yymsp[-4].minor.yy346.zStart;
-    yygotominor.yy346.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
+    if( yymsp[-3].minor.yy4 ) yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy118.pExpr, 0, 0);
+    yygotominor.yy118.zStart = yymsp[-4].minor.yy118.zStart;
+    yygotominor.yy118.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
   }
         break;
-      case 231: /* expr ::= expr in_op nm dbnm */
+      case 230: /* expr ::= expr in_op nm dbnm */
 {
     SrcList *pSrc = sqlite3SrcListAppend(pParse->db, 0,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy0);
-    yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_IN, yymsp[-3].minor.yy346.pExpr, 0, 0);
-    if( yygotominor.yy346.pExpr ){
-      yygotominor.yy346.pExpr->x.pSelect = sqlite3SelectNew(pParse, 0,pSrc,0,0,0,0,0,0,0);
-      ExprSetProperty(yygotominor.yy346.pExpr, EP_xIsSelect);
-      sqlite3ExprSetHeight(pParse, yygotominor.yy346.pExpr);
+    yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_IN, yymsp[-3].minor.yy118.pExpr, 0, 0);
+    if( yygotominor.yy118.pExpr ){
+      yygotominor.yy118.pExpr->x.pSelect = sqlite3SelectNew(pParse, 0,pSrc,0,0,0,0,0,0,0);
+      ExprSetProperty(yygotominor.yy118.pExpr, EP_xIsSelect);
+      sqlite3ExprSetHeight(pParse, yygotominor.yy118.pExpr);
     }else{
       sqlite3SrcListDelete(pParse->db, pSrc);
     }
-    if( yymsp[-2].minor.yy328 ) yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy346.pExpr, 0, 0);
-    yygotominor.yy346.zStart = yymsp[-3].minor.yy346.zStart;
-    yygotominor.yy346.zEnd = yymsp[0].minor.yy0.z ? &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n] : &yymsp[-1].minor.yy0.z[yymsp[-1].minor.yy0.n];
+    if( yymsp[-2].minor.yy4 ) yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy118.pExpr, 0, 0);
+    yygotominor.yy118.zStart = yymsp[-3].minor.yy118.zStart;
+    yygotominor.yy118.zEnd = yymsp[0].minor.yy0.z ? &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n] : &yymsp[-1].minor.yy0.z[yymsp[-1].minor.yy0.n];
   }
         break;
-      case 232: /* expr ::= EXISTS LP select RP */
+      case 231: /* expr ::= EXISTS LP select RP */
 {
-    Expr *p = yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_EXISTS, 0, 0, 0);
+    Expr *p = yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_EXISTS, 0, 0, 0);
     if( p ){
-      p->x.pSelect = yymsp[-1].minor.yy3;
+      p->x.pSelect = yymsp[-1].minor.yy387;
       ExprSetProperty(p, EP_xIsSelect);
       sqlite3ExprSetHeight(pParse, p);
     }else{
-      sqlite3SelectDelete(pParse->db, yymsp[-1].minor.yy3);
+      sqlite3SelectDelete(pParse->db, yymsp[-1].minor.yy387);
     }
-    yygotominor.yy346.zStart = yymsp[-3].minor.yy0.z;
-    yygotominor.yy346.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
+    yygotominor.yy118.zStart = yymsp[-3].minor.yy0.z;
+    yygotominor.yy118.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
   }
         break;
-      case 233: /* expr ::= CASE case_operand case_exprlist case_else END */
+      case 232: /* expr ::= CASE case_operand case_exprlist case_else END */
 {
-  yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_CASE, yymsp[-3].minor.yy132, yymsp[-1].minor.yy132, 0);
-  if( yygotominor.yy346.pExpr ){
-    yygotominor.yy346.pExpr->x.pList = yymsp[-2].minor.yy14;
-    sqlite3ExprSetHeight(pParse, yygotominor.yy346.pExpr);
+  yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_CASE, yymsp[-3].minor.yy314, yymsp[-1].minor.yy314, 0);
+  if( yygotominor.yy118.pExpr ){
+    yygotominor.yy118.pExpr->x.pList = yymsp[-2].minor.yy322;
+    sqlite3ExprSetHeight(pParse, yygotominor.yy118.pExpr);
   }else{
-    sqlite3ExprListDelete(pParse->db, yymsp[-2].minor.yy14);
+    sqlite3ExprListDelete(pParse->db, yymsp[-2].minor.yy322);
   }
-  yygotominor.yy346.zStart = yymsp[-4].minor.yy0.z;
-  yygotominor.yy346.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
+  yygotominor.yy118.zStart = yymsp[-4].minor.yy0.z;
+  yygotominor.yy118.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
 }
         break;
-      case 234: /* case_exprlist ::= case_exprlist WHEN expr THEN expr */
+      case 233: /* case_exprlist ::= case_exprlist WHEN expr THEN expr */
 {
-  yygotominor.yy14 = sqlite3ExprListAppend(pParse,yymsp[-4].minor.yy14, yymsp[-2].minor.yy346.pExpr);
-  yygotominor.yy14 = sqlite3ExprListAppend(pParse,yygotominor.yy14, yymsp[0].minor.yy346.pExpr);
+  yygotominor.yy322 = sqlite3ExprListAppend(pParse,yymsp[-4].minor.yy322, yymsp[-2].minor.yy118.pExpr);
+  yygotominor.yy322 = sqlite3ExprListAppend(pParse,yygotominor.yy322, yymsp[0].minor.yy118.pExpr);
 }
         break;
-      case 235: /* case_exprlist ::= WHEN expr THEN expr */
+      case 234: /* case_exprlist ::= WHEN expr THEN expr */
 {
-  yygotominor.yy14 = sqlite3ExprListAppend(pParse,0, yymsp[-2].minor.yy346.pExpr);
-  yygotominor.yy14 = sqlite3ExprListAppend(pParse,yygotominor.yy14, yymsp[0].minor.yy346.pExpr);
+  yygotominor.yy322 = sqlite3ExprListAppend(pParse,0, yymsp[-2].minor.yy118.pExpr);
+  yygotominor.yy322 = sqlite3ExprListAppend(pParse,yygotominor.yy322, yymsp[0].minor.yy118.pExpr);
 }
         break;
-      case 244: /* cmd ::= createkw uniqueflag INDEX ifnotexists nm dbnm ON nm LP idxlist RP */
+      case 243: /* cmd ::= createkw uniqueflag INDEX ifnotexists nm dbnm ON nm LP idxlist RP */
 {
   sqlite3CreateIndex(pParse, &yymsp[-6].minor.yy0, &yymsp[-5].minor.yy0, 
-                     sqlite3SrcListAppend(pParse->db,0,&yymsp[-3].minor.yy0,0), yymsp[-1].minor.yy14, yymsp[-9].minor.yy328,
-                      &yymsp[-10].minor.yy0, &yymsp[0].minor.yy0, SQLITE_SO_ASC, yymsp[-7].minor.yy328);
+                     sqlite3SrcListAppend(pParse->db,0,&yymsp[-3].minor.yy0,0), yymsp[-1].minor.yy322, yymsp[-9].minor.yy4,
+                      &yymsp[-10].minor.yy0, &yymsp[0].minor.yy0, SQLITE_SO_ASC, yymsp[-7].minor.yy4);
 }
         break;
-      case 245: /* uniqueflag ::= UNIQUE */
-      case 299: /* raisetype ::= ABORT */ yytestcase(yyruleno==299);
-{yygotominor.yy328 = OE_Abort;}
+      case 244: /* uniqueflag ::= UNIQUE */
+      case 298: /* raisetype ::= ABORT */ yytestcase(yyruleno==298);
+{yygotominor.yy4 = OE_Abort;}
         break;
-      case 246: /* uniqueflag ::= */
-{yygotominor.yy328 = OE_None;}
+      case 245: /* uniqueflag ::= */
+{yygotominor.yy4 = OE_None;}
         break;
-      case 249: /* idxlist ::= idxlist COMMA nm collate sortorder */
+      case 248: /* idxlist ::= idxlist COMMA nm collate sortorder */
 {
   Expr *p = 0;
   if( yymsp[-1].minor.yy0.n>0 ){
     p = sqlite3Expr(pParse->db, TK_COLUMN, 0);
-    sqlite3ExprSetColl(pParse, p, &yymsp[-1].minor.yy0);
+    sqlite3ExprSetCollByToken(pParse, p, &yymsp[-1].minor.yy0);
   }
-  yygotominor.yy14 = sqlite3ExprListAppend(pParse,yymsp[-4].minor.yy14, p);
-  sqlite3ExprListSetName(pParse,yygotominor.yy14,&yymsp[-2].minor.yy0,1);
-  sqlite3ExprListCheckLength(pParse, yygotominor.yy14, "index");
-  if( yygotominor.yy14 ) yygotominor.yy14->a[yygotominor.yy14->nExpr-1].sortOrder = (u8)yymsp[0].minor.yy328;
+  yygotominor.yy322 = sqlite3ExprListAppend(pParse,yymsp[-4].minor.yy322, p);
+  sqlite3ExprListSetName(pParse,yygotominor.yy322,&yymsp[-2].minor.yy0,1);
+  sqlite3ExprListCheckLength(pParse, yygotominor.yy322, "index");
+  if( yygotominor.yy322 ) yygotominor.yy322->a[yygotominor.yy322->nExpr-1].sortOrder = (u8)yymsp[0].minor.yy4;
 }
         break;
-      case 250: /* idxlist ::= nm collate sortorder */
+      case 249: /* idxlist ::= nm collate sortorder */
 {
   Expr *p = 0;
   if( yymsp[-1].minor.yy0.n>0 ){
     p = sqlite3PExpr(pParse, TK_COLUMN, 0, 0, 0);
-    sqlite3ExprSetColl(pParse, p, &yymsp[-1].minor.yy0);
+    sqlite3ExprSetCollByToken(pParse, p, &yymsp[-1].minor.yy0);
   }
-  yygotominor.yy14 = sqlite3ExprListAppend(pParse,0, p);
-  sqlite3ExprListSetName(pParse, yygotominor.yy14, &yymsp[-2].minor.yy0, 1);
-  sqlite3ExprListCheckLength(pParse, yygotominor.yy14, "index");
-  if( yygotominor.yy14 ) yygotominor.yy14->a[yygotominor.yy14->nExpr-1].sortOrder = (u8)yymsp[0].minor.yy328;
+  yygotominor.yy322 = sqlite3ExprListAppend(pParse,0, p);
+  sqlite3ExprListSetName(pParse, yygotominor.yy322, &yymsp[-2].minor.yy0, 1);
+  sqlite3ExprListCheckLength(pParse, yygotominor.yy322, "index");
+  if( yygotominor.yy322 ) yygotominor.yy322->a[yygotominor.yy322->nExpr-1].sortOrder = (u8)yymsp[0].minor.yy4;
 }
         break;
-      case 251: /* collate ::= */
+      case 250: /* collate ::= */
 {yygotominor.yy0.z = 0; yygotominor.yy0.n = 0;}
         break;
-      case 253: /* cmd ::= DROP INDEX ifexists fullname */
-{sqlite3DropIndex(pParse, yymsp[0].minor.yy65, yymsp[-1].minor.yy328);}
+      case 252: /* cmd ::= DROP INDEX ifexists fullname */
+{sqlite3DropIndex(pParse, yymsp[0].minor.yy259, yymsp[-1].minor.yy4);}
         break;
-      case 254: /* cmd ::= VACUUM */
-      case 255: /* cmd ::= VACUUM nm */ yytestcase(yyruleno==255);
+      case 253: /* cmd ::= VACUUM */
+      case 254: /* cmd ::= VACUUM nm */ yytestcase(yyruleno==254);
 {sqlite3Vacuum(pParse);}
         break;
-      case 256: /* cmd ::= PRAGMA nm dbnm */
+      case 255: /* cmd ::= PRAGMA nm dbnm */
 {sqlite3Pragma(pParse,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy0,0,0);}
         break;
-      case 257: /* cmd ::= PRAGMA nm dbnm EQ nmnum */
+      case 256: /* cmd ::= PRAGMA nm dbnm EQ nmnum */
 {sqlite3Pragma(pParse,&yymsp[-3].minor.yy0,&yymsp[-2].minor.yy0,&yymsp[0].minor.yy0,0);}
         break;
-      case 258: /* cmd ::= PRAGMA nm dbnm LP nmnum RP */
+      case 257: /* cmd ::= PRAGMA nm dbnm LP nmnum RP */
 {sqlite3Pragma(pParse,&yymsp[-4].minor.yy0,&yymsp[-3].minor.yy0,&yymsp[-1].minor.yy0,0);}
         break;
-      case 259: /* cmd ::= PRAGMA nm dbnm EQ minus_num */
+      case 258: /* cmd ::= PRAGMA nm dbnm EQ minus_num */
 {sqlite3Pragma(pParse,&yymsp[-3].minor.yy0,&yymsp[-2].minor.yy0,&yymsp[0].minor.yy0,1);}
         break;
-      case 260: /* cmd ::= PRAGMA nm dbnm LP minus_num RP */
+      case 259: /* cmd ::= PRAGMA nm dbnm LP minus_num RP */
 {sqlite3Pragma(pParse,&yymsp[-4].minor.yy0,&yymsp[-3].minor.yy0,&yymsp[-1].minor.yy0,1);}
         break;
-      case 271: /* cmd ::= createkw trigger_decl BEGIN trigger_cmd_list END */
+      case 270: /* cmd ::= createkw trigger_decl BEGIN trigger_cmd_list END */
 {
   Token all;
   all.z = yymsp[-3].minor.yy0.z;
   all.n = (int)(yymsp[0].minor.yy0.z - yymsp[-3].minor.yy0.z) + yymsp[0].minor.yy0.n;
-  sqlite3FinishTrigger(pParse, yymsp[-1].minor.yy473, &all);
+  sqlite3FinishTrigger(pParse, yymsp[-1].minor.yy203, &all);
 }
         break;
-      case 272: /* trigger_decl ::= temp TRIGGER ifnotexists nm dbnm trigger_time trigger_event ON fullname foreach_clause when_clause */
+      case 271: /* trigger_decl ::= temp TRIGGER ifnotexists nm dbnm trigger_time trigger_event ON fullname foreach_clause when_clause */
 {
-  sqlite3BeginTrigger(pParse, &yymsp[-7].minor.yy0, &yymsp[-6].minor.yy0, yymsp[-5].minor.yy328, yymsp[-4].minor.yy378.a, yymsp[-4].minor.yy378.b, yymsp[-2].minor.yy65, yymsp[0].minor.yy132, yymsp[-10].minor.yy328, yymsp[-8].minor.yy328);
+  sqlite3BeginTrigger(pParse, &yymsp[-7].minor.yy0, &yymsp[-6].minor.yy0, yymsp[-5].minor.yy4, yymsp[-4].minor.yy90.a, yymsp[-4].minor.yy90.b, yymsp[-2].minor.yy259, yymsp[0].minor.yy314, yymsp[-10].minor.yy4, yymsp[-8].minor.yy4);
   yygotominor.yy0 = (yymsp[-6].minor.yy0.n==0?yymsp[-7].minor.yy0:yymsp[-6].minor.yy0);
 }
         break;
-      case 273: /* trigger_time ::= BEFORE */
-      case 276: /* trigger_time ::= */ yytestcase(yyruleno==276);
-{ yygotominor.yy328 = TK_BEFORE; }
+      case 272: /* trigger_time ::= BEFORE */
+      case 275: /* trigger_time ::= */ yytestcase(yyruleno==275);
+{ yygotominor.yy4 = TK_BEFORE; }
         break;
-      case 274: /* trigger_time ::= AFTER */
-{ yygotominor.yy328 = TK_AFTER;  }
+      case 273: /* trigger_time ::= AFTER */
+{ yygotominor.yy4 = TK_AFTER;  }
         break;
-      case 275: /* trigger_time ::= INSTEAD OF */
-{ yygotominor.yy328 = TK_INSTEAD;}
+      case 274: /* trigger_time ::= INSTEAD OF */
+{ yygotominor.yy4 = TK_INSTEAD;}
         break;
-      case 277: /* trigger_event ::= DELETE|INSERT */
-      case 278: /* trigger_event ::= UPDATE */ yytestcase(yyruleno==278);
-{yygotominor.yy378.a = yymsp[0].major; yygotominor.yy378.b = 0;}
+      case 276: /* trigger_event ::= DELETE|INSERT */
+      case 277: /* trigger_event ::= UPDATE */ yytestcase(yyruleno==277);
+{yygotominor.yy90.a = yymsp[0].major; yygotominor.yy90.b = 0;}
         break;
-      case 279: /* trigger_event ::= UPDATE OF inscollist */
-{yygotominor.yy378.a = TK_UPDATE; yygotominor.yy378.b = yymsp[0].minor.yy408;}
+      case 278: /* trigger_event ::= UPDATE OF inscollist */
+{yygotominor.yy90.a = TK_UPDATE; yygotominor.yy90.b = yymsp[0].minor.yy384;}
         break;
-      case 282: /* when_clause ::= */
-      case 304: /* key_opt ::= */ yytestcase(yyruleno==304);
-{ yygotominor.yy132 = 0; }
+      case 281: /* when_clause ::= */
+      case 303: /* key_opt ::= */ yytestcase(yyruleno==303);
+{ yygotominor.yy314 = 0; }
         break;
-      case 283: /* when_clause ::= WHEN expr */
-      case 305: /* key_opt ::= KEY expr */ yytestcase(yyruleno==305);
-{ yygotominor.yy132 = yymsp[0].minor.yy346.pExpr; }
+      case 282: /* when_clause ::= WHEN expr */
+      case 304: /* key_opt ::= KEY expr */ yytestcase(yyruleno==304);
+{ yygotominor.yy314 = yymsp[0].minor.yy118.pExpr; }
         break;
-      case 284: /* trigger_cmd_list ::= trigger_cmd_list trigger_cmd SEMI */
+      case 283: /* trigger_cmd_list ::= trigger_cmd_list trigger_cmd SEMI */
 {
-  assert( yymsp[-2].minor.yy473!=0 );
-  yymsp[-2].minor.yy473->pLast->pNext = yymsp[-1].minor.yy473;
-  yymsp[-2].minor.yy473->pLast = yymsp[-1].minor.yy473;
-  yygotominor.yy473 = yymsp[-2].minor.yy473;
+  assert( yymsp[-2].minor.yy203!=0 );
+  yymsp[-2].minor.yy203->pLast->pNext = yymsp[-1].minor.yy203;
+  yymsp[-2].minor.yy203->pLast = yymsp[-1].minor.yy203;
+  yygotominor.yy203 = yymsp[-2].minor.yy203;
 }
         break;
-      case 285: /* trigger_cmd_list ::= trigger_cmd SEMI */
+      case 284: /* trigger_cmd_list ::= trigger_cmd SEMI */
 { 
-  assert( yymsp[-1].minor.yy473!=0 );
-  yymsp[-1].minor.yy473->pLast = yymsp[-1].minor.yy473;
-  yygotominor.yy473 = yymsp[-1].minor.yy473;
+  assert( yymsp[-1].minor.yy203!=0 );
+  yymsp[-1].minor.yy203->pLast = yymsp[-1].minor.yy203;
+  yygotominor.yy203 = yymsp[-1].minor.yy203;
 }
         break;
-      case 287: /* trnm ::= nm DOT nm */
+      case 286: /* trnm ::= nm DOT nm */
 {
   yygotominor.yy0 = yymsp[0].minor.yy0;
   sqlite3ErrorMsg(pParse, 
@@ -100515,121 +102355,121 @@
         "statements within triggers");
 }
         break;
-      case 289: /* tridxby ::= INDEXED BY nm */
+      case 288: /* tridxby ::= INDEXED BY nm */
 {
   sqlite3ErrorMsg(pParse,
         "the INDEXED BY clause is not allowed on UPDATE or DELETE statements "
         "within triggers");
 }
         break;
-      case 290: /* tridxby ::= NOT INDEXED */
+      case 289: /* tridxby ::= NOT INDEXED */
 {
   sqlite3ErrorMsg(pParse,
         "the NOT INDEXED clause is not allowed on UPDATE or DELETE statements "
         "within triggers");
 }
         break;
-      case 291: /* trigger_cmd ::= UPDATE orconf trnm tridxby SET setlist where_opt */
-{ yygotominor.yy473 = sqlite3TriggerUpdateStep(pParse->db, &yymsp[-4].minor.yy0, yymsp[-1].minor.yy14, yymsp[0].minor.yy132, yymsp[-5].minor.yy186); }
+      case 290: /* trigger_cmd ::= UPDATE orconf trnm tridxby SET setlist where_opt */
+{ yygotominor.yy203 = sqlite3TriggerUpdateStep(pParse->db, &yymsp[-4].minor.yy0, yymsp[-1].minor.yy322, yymsp[0].minor.yy314, yymsp[-5].minor.yy210); }
         break;
-      case 292: /* trigger_cmd ::= insert_cmd INTO trnm inscollist_opt VALUES LP itemlist RP */
-{yygotominor.yy473 = sqlite3TriggerInsertStep(pParse->db, &yymsp[-5].minor.yy0, yymsp[-4].minor.yy408, yymsp[-1].minor.yy14, 0, yymsp[-7].minor.yy186);}
+      case 291: /* trigger_cmd ::= insert_cmd INTO trnm inscollist_opt VALUES LP itemlist RP */
+{yygotominor.yy203 = sqlite3TriggerInsertStep(pParse->db, &yymsp[-5].minor.yy0, yymsp[-4].minor.yy384, yymsp[-1].minor.yy322, 0, yymsp[-7].minor.yy210);}
         break;
-      case 293: /* trigger_cmd ::= insert_cmd INTO trnm inscollist_opt select */
-{yygotominor.yy473 = sqlite3TriggerInsertStep(pParse->db, &yymsp[-2].minor.yy0, yymsp[-1].minor.yy408, 0, yymsp[0].minor.yy3, yymsp[-4].minor.yy186);}
+      case 292: /* trigger_cmd ::= insert_cmd INTO trnm inscollist_opt select */
+{yygotominor.yy203 = sqlite3TriggerInsertStep(pParse->db, &yymsp[-2].minor.yy0, yymsp[-1].minor.yy384, 0, yymsp[0].minor.yy387, yymsp[-4].minor.yy210);}
         break;
-      case 294: /* trigger_cmd ::= DELETE FROM trnm tridxby where_opt */
-{yygotominor.yy473 = sqlite3TriggerDeleteStep(pParse->db, &yymsp[-2].minor.yy0, yymsp[0].minor.yy132);}
+      case 293: /* trigger_cmd ::= DELETE FROM trnm tridxby where_opt */
+{yygotominor.yy203 = sqlite3TriggerDeleteStep(pParse->db, &yymsp[-2].minor.yy0, yymsp[0].minor.yy314);}
         break;
-      case 295: /* trigger_cmd ::= select */
-{yygotominor.yy473 = sqlite3TriggerSelectStep(pParse->db, yymsp[0].minor.yy3); }
+      case 294: /* trigger_cmd ::= select */
+{yygotominor.yy203 = sqlite3TriggerSelectStep(pParse->db, yymsp[0].minor.yy387); }
         break;
-      case 296: /* expr ::= RAISE LP IGNORE RP */
+      case 295: /* expr ::= RAISE LP IGNORE RP */
 {
-  yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_RAISE, 0, 0, 0); 
-  if( yygotominor.yy346.pExpr ){
-    yygotominor.yy346.pExpr->affinity = OE_Ignore;
+  yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_RAISE, 0, 0, 0); 
+  if( yygotominor.yy118.pExpr ){
+    yygotominor.yy118.pExpr->affinity = OE_Ignore;
   }
-  yygotominor.yy346.zStart = yymsp[-3].minor.yy0.z;
-  yygotominor.yy346.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
+  yygotominor.yy118.zStart = yymsp[-3].minor.yy0.z;
+  yygotominor.yy118.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
 }
         break;
-      case 297: /* expr ::= RAISE LP raisetype COMMA nm RP */
+      case 296: /* expr ::= RAISE LP raisetype COMMA nm RP */
 {
-  yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_RAISE, 0, 0, &yymsp[-1].minor.yy0); 
-  if( yygotominor.yy346.pExpr ) {
-    yygotominor.yy346.pExpr->affinity = (char)yymsp[-3].minor.yy328;
+  yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_RAISE, 0, 0, &yymsp[-1].minor.yy0); 
+  if( yygotominor.yy118.pExpr ) {
+    yygotominor.yy118.pExpr->affinity = (char)yymsp[-3].minor.yy4;
   }
-  yygotominor.yy346.zStart = yymsp[-5].minor.yy0.z;
-  yygotominor.yy346.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
+  yygotominor.yy118.zStart = yymsp[-5].minor.yy0.z;
+  yygotominor.yy118.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
 }
         break;
-      case 298: /* raisetype ::= ROLLBACK */
-{yygotominor.yy328 = OE_Rollback;}
+      case 297: /* raisetype ::= ROLLBACK */
+{yygotominor.yy4 = OE_Rollback;}
         break;
-      case 300: /* raisetype ::= FAIL */
-{yygotominor.yy328 = OE_Fail;}
+      case 299: /* raisetype ::= FAIL */
+{yygotominor.yy4 = OE_Fail;}
         break;
-      case 301: /* cmd ::= DROP TRIGGER ifexists fullname */
+      case 300: /* cmd ::= DROP TRIGGER ifexists fullname */
 {
-  sqlite3DropTrigger(pParse,yymsp[0].minor.yy65,yymsp[-1].minor.yy328);
+  sqlite3DropTrigger(pParse,yymsp[0].minor.yy259,yymsp[-1].minor.yy4);
 }
         break;
-      case 302: /* cmd ::= ATTACH database_kw_opt expr AS expr key_opt */
+      case 301: /* cmd ::= ATTACH database_kw_opt expr AS expr key_opt */
 {
-  sqlite3Attach(pParse, yymsp[-3].minor.yy346.pExpr, yymsp[-1].minor.yy346.pExpr, yymsp[0].minor.yy132);
+  sqlite3Attach(pParse, yymsp[-3].minor.yy118.pExpr, yymsp[-1].minor.yy118.pExpr, yymsp[0].minor.yy314);
 }
         break;
-      case 303: /* cmd ::= DETACH database_kw_opt expr */
+      case 302: /* cmd ::= DETACH database_kw_opt expr */
 {
-  sqlite3Detach(pParse, yymsp[0].minor.yy346.pExpr);
+  sqlite3Detach(pParse, yymsp[0].minor.yy118.pExpr);
 }
         break;
-      case 308: /* cmd ::= REINDEX */
+      case 307: /* cmd ::= REINDEX */
 {sqlite3Reindex(pParse, 0, 0);}
         break;
-      case 309: /* cmd ::= REINDEX nm dbnm */
+      case 308: /* cmd ::= REINDEX nm dbnm */
 {sqlite3Reindex(pParse, &yymsp[-1].minor.yy0, &yymsp[0].minor.yy0);}
         break;
-      case 310: /* cmd ::= ANALYZE */
+      case 309: /* cmd ::= ANALYZE */
 {sqlite3Analyze(pParse, 0, 0);}
         break;
-      case 311: /* cmd ::= ANALYZE nm dbnm */
+      case 310: /* cmd ::= ANALYZE nm dbnm */
 {sqlite3Analyze(pParse, &yymsp[-1].minor.yy0, &yymsp[0].minor.yy0);}
         break;
-      case 312: /* cmd ::= ALTER TABLE fullname RENAME TO nm */
+      case 311: /* cmd ::= ALTER TABLE fullname RENAME TO nm */
 {
-  sqlite3AlterRenameTable(pParse,yymsp[-3].minor.yy65,&yymsp[0].minor.yy0);
+  sqlite3AlterRenameTable(pParse,yymsp[-3].minor.yy259,&yymsp[0].minor.yy0);
 }
         break;
-      case 313: /* cmd ::= ALTER TABLE add_column_fullname ADD kwcolumn_opt column */
+      case 312: /* cmd ::= ALTER TABLE add_column_fullname ADD kwcolumn_opt column */
 {
   sqlite3AlterFinishAddColumn(pParse, &yymsp[0].minor.yy0);
 }
         break;
-      case 314: /* add_column_fullname ::= fullname */
+      case 313: /* add_column_fullname ::= fullname */
 {
   pParse->db->lookaside.bEnabled = 0;
-  sqlite3AlterBeginAddColumn(pParse, yymsp[0].minor.yy65);
+  sqlite3AlterBeginAddColumn(pParse, yymsp[0].minor.yy259);
 }
         break;
-      case 317: /* cmd ::= create_vtab */
+      case 316: /* cmd ::= create_vtab */
 {sqlite3VtabFinishParse(pParse,0);}
         break;
-      case 318: /* cmd ::= create_vtab LP vtabarglist RP */
+      case 317: /* cmd ::= create_vtab LP vtabarglist RP */
 {sqlite3VtabFinishParse(pParse,&yymsp[0].minor.yy0);}
         break;
-      case 319: /* create_vtab ::= createkw VIRTUAL TABLE nm dbnm USING nm */
+      case 318: /* create_vtab ::= createkw VIRTUAL TABLE nm dbnm USING nm */
 {
     sqlite3VtabBeginParse(pParse, &yymsp[-3].minor.yy0, &yymsp[-2].minor.yy0, &yymsp[0].minor.yy0);
 }
         break;
-      case 322: /* vtabarg ::= */
+      case 321: /* vtabarg ::= */
 {sqlite3VtabArgInit(pParse);}
         break;
-      case 324: /* vtabargtoken ::= ANY */
-      case 325: /* vtabargtoken ::= lp anylist RP */ yytestcase(yyruleno==325);
-      case 326: /* lp ::= LP */ yytestcase(yyruleno==326);
+      case 323: /* vtabargtoken ::= ANY */
+      case 324: /* vtabargtoken ::= lp anylist RP */ yytestcase(yyruleno==324);
+      case 325: /* lp ::= LP */ yytestcase(yyruleno==325);
 {sqlite3VtabArgExtend(pParse,&yymsp[0].minor.yy0);}
         break;
       default:
@@ -100658,21 +102498,21 @@
       /* (91) conslist ::= conslist tcons */ yytestcase(yyruleno==91);
       /* (92) conslist ::= tcons */ yytestcase(yyruleno==92);
       /* (93) tcons ::= CONSTRAINT nm */ yytestcase(yyruleno==93);
-      /* (269) plus_opt ::= PLUS */ yytestcase(yyruleno==269);
-      /* (270) plus_opt ::= */ yytestcase(yyruleno==270);
-      /* (280) foreach_clause ::= */ yytestcase(yyruleno==280);
-      /* (281) foreach_clause ::= FOR EACH ROW */ yytestcase(yyruleno==281);
-      /* (288) tridxby ::= */ yytestcase(yyruleno==288);
-      /* (306) database_kw_opt ::= DATABASE */ yytestcase(yyruleno==306);
-      /* (307) database_kw_opt ::= */ yytestcase(yyruleno==307);
-      /* (315) kwcolumn_opt ::= */ yytestcase(yyruleno==315);
-      /* (316) kwcolumn_opt ::= COLUMNKW */ yytestcase(yyruleno==316);
-      /* (320) vtabarglist ::= vtabarg */ yytestcase(yyruleno==320);
-      /* (321) vtabarglist ::= vtabarglist COMMA vtabarg */ yytestcase(yyruleno==321);
-      /* (323) vtabarg ::= vtabarg vtabargtoken */ yytestcase(yyruleno==323);
-      /* (327) anylist ::= */ yytestcase(yyruleno==327);
-      /* (328) anylist ::= anylist LP anylist RP */ yytestcase(yyruleno==328);
-      /* (329) anylist ::= anylist ANY */ yytestcase(yyruleno==329);
+      /* (268) plus_opt ::= PLUS */ yytestcase(yyruleno==268);
+      /* (269) plus_opt ::= */ yytestcase(yyruleno==269);
+      /* (279) foreach_clause ::= */ yytestcase(yyruleno==279);
+      /* (280) foreach_clause ::= FOR EACH ROW */ yytestcase(yyruleno==280);
+      /* (287) tridxby ::= */ yytestcase(yyruleno==287);
+      /* (305) database_kw_opt ::= DATABASE */ yytestcase(yyruleno==305);
+      /* (306) database_kw_opt ::= */ yytestcase(yyruleno==306);
+      /* (314) kwcolumn_opt ::= */ yytestcase(yyruleno==314);
+      /* (315) kwcolumn_opt ::= COLUMNKW */ yytestcase(yyruleno==315);
+      /* (319) vtabarglist ::= vtabarg */ yytestcase(yyruleno==319);
+      /* (320) vtabarglist ::= vtabarglist COMMA vtabarg */ yytestcase(yyruleno==320);
+      /* (322) vtabarg ::= vtabarg vtabargtoken */ yytestcase(yyruleno==322);
+      /* (326) anylist ::= */ yytestcase(yyruleno==326);
+      /* (327) anylist ::= anylist LP anylist RP */ yytestcase(yyruleno==327);
+      /* (328) anylist ::= anylist ANY */ yytestcase(yyruleno==328);
         break;
   };
   yygoto = yyRuleInfo[yyruleno].lhs;
@@ -101700,7 +103540,7 @@
   }
 #endif
 #ifndef SQLITE_OMIT_VIRTUALTABLE
-  sqlite3DbFree(db, pParse->apVtabLock);
+  sqlite3_free(pParse->apVtabLock);
 #endif
 
   if( !IN_DECLARE_VTAB ){
@@ -101708,7 +103548,7 @@
     ** structure built up in pParse->pNewTable. The calling code (see vtab.c)
     ** will take responsibility for freeing the Table structure.
     */
-    sqlite3DeleteTable(pParse->pNewTable);
+    sqlite3DeleteTable(db, pParse->pNewTable);
   }
 
   sqlite3DeleteTrigger(db, pParse->pNewTrigger);
@@ -101722,7 +103562,7 @@
   while( pParse->pZombieTab ){
     Table *p = pParse->pZombieTab;
     pParse->pZombieTab = p->pNextZombie;
-    sqlite3DeleteTable(p);
+    sqlite3DeleteTable(db, p);
   }
   if( nErr>0 && pParse->rc==SQLITE_OK ){
     pParse->rc = SQLITE_ERROR;
@@ -102132,15 +103972,33 @@
 /************** Continuing where we left off in main.c ***********************/
 #endif
 
-/*
-** The version of the library
-*/
 #ifndef SQLITE_AMALGAMATION
+/* IMPLEMENTATION-OF: R-46656-45156 The sqlite3_version[] string constant
+** contains the text of SQLITE_VERSION macro. 
+*/
 SQLITE_API const char sqlite3_version[] = SQLITE_VERSION;
 #endif
+
+/* IMPLEMENTATION-OF: R-53536-42575 The sqlite3_libversion() function returns
+** a pointer to the to the sqlite3_version[] string constant. 
+*/
 SQLITE_API const char *sqlite3_libversion(void){ return sqlite3_version; }
+
+/* IMPLEMENTATION-OF: R-63124-39300 The sqlite3_sourceid() function returns a
+** pointer to a string constant whose value is the same as the
+** SQLITE_SOURCE_ID C preprocessor macro. 
+*/
 SQLITE_API const char *sqlite3_sourceid(void){ return SQLITE_SOURCE_ID; }
+
+/* IMPLEMENTATION-OF: R-35210-63508 The sqlite3_libversion_number() function
+** returns an integer equal to SQLITE_VERSION_NUMBER.
+*/
 SQLITE_API int sqlite3_libversion_number(void){ return SQLITE_VERSION_NUMBER; }
+
+/* IMPLEMENTATION-OF: R-54823-41343 The sqlite3_threadsafe() function returns
+** zero if and only if SQLite was compiled mutexing code omitted due to
+** the SQLITE_THREADSAFE compile-time option being set to 0.
+*/
 SQLITE_API int sqlite3_threadsafe(void){ return SQLITE_THREADSAFE; }
 
 #if !defined(SQLITE_OMIT_TRACE) && defined(SQLITE_ENABLE_IOTRACE)
@@ -102261,6 +104119,13 @@
   ** sqlite3_initialize().  The recursive calls normally come through
   ** sqlite3_os_init() when it invokes sqlite3_vfs_register(), but other
   ** recursive calls might also be possible.
+  **
+  ** IMPLEMENTATION-OF: R-00140-37445 SQLite automatically serializes calls
+  ** to the xInit method, so the xInit method need not be threadsafe.
+  **
+  ** The following mutex is what serializes access to the appdef pcache xInit
+  ** methods.  The sqlite3_pcache_methods.xInit() all is embedded in the
+  ** call to sqlite3PcacheInitialize().
   */
   sqlite3_mutex_enter(sqlite3GlobalConfig.pInitMutex);
   if( sqlite3GlobalConfig.isInit==0 && sqlite3GlobalConfig.inProgress==0 ){
@@ -102541,12 +104406,12 @@
     sz = 0;
     pStart = 0;
   }else if( pBuf==0 ){
-    sz = ROUND8(sz);
+    sz = ROUNDDOWN8(sz); /* IMP: R-33038-09382 */
     sqlite3BeginBenignMalloc();
-    pStart = sqlite3Malloc( sz*cnt );
+    pStart = sqlite3Malloc( sz*cnt );  /* IMP: R-61949-35727 */
     sqlite3EndBenignMalloc();
   }else{
-    sz = ROUNDDOWN8(sz);
+    sz = ROUNDDOWN8(sz); /* IMP: R-33038-09382 */
     pStart = pBuf;
   }
   db->lookaside.pStart = pStart;
@@ -102589,14 +104454,14 @@
   va_start(ap, op);
   switch( op ){
     case SQLITE_DBCONFIG_LOOKASIDE: {
-      void *pBuf = va_arg(ap, void*);
-      int sz = va_arg(ap, int);
-      int cnt = va_arg(ap, int);
+      void *pBuf = va_arg(ap, void*); /* IMP: R-21112-12275 */
+      int sz = va_arg(ap, int);       /* IMP: R-47871-25994 */
+      int cnt = va_arg(ap, int);      /* IMP: R-04460-53386 */
       rc = setupLookaside(db, pBuf, sz, cnt);
       break;
     }
     default: {
-      rc = SQLITE_ERROR;
+      rc = SQLITE_ERROR; /* IMP: R-42790-23372 */
       break;
     }
   }
@@ -102702,10 +104567,27 @@
 }
 
 /*
+** Invoke the destructor function associated with FuncDef p, if any. Except,
+** if this is not the last copy of the function, do not invoke it. Multiple
+** copies of a single function are created when create_function() is called
+** with SQLITE_ANY as the encoding.
+*/
+static void functionDestroy(sqlite3 *db, FuncDef *p){
+  FuncDestructor *pDestructor = p->pDestructor;
+  if( pDestructor ){
+    pDestructor->nRef--;
+    if( pDestructor->nRef==0 ){
+      pDestructor->xDestroy(pDestructor->pUserData);
+      sqlite3DbFree(db, pDestructor);
+    }
+  }
+}
+
+/*
 ** Close an existing SQLite database
 */
 SQLITE_API int sqlite3_close(sqlite3 *db){
-  HashElem *i;
+  HashElem *i;                    /* Hash table iterator */
   int j;
 
   if( !db ){
@@ -102739,7 +104621,7 @@
 
     sqlite3_mutex_leave(db->mutex);
     return SQLITE_UNCLOSED;
-  }
+    }
   assert( sqlite3SafetyCheckSickOrOk(db) );
 
   for(j=0; j<db->nDb; j++){
@@ -102779,6 +104661,7 @@
     for(p=db->aFunc.a[j]; p; p=pHash){
       pHash = p->pHash;
       while( p ){
+        functionDestroy(db, p);
         pNext = p->pNext;
         sqlite3DbFree(db, p);
         p = pNext;
@@ -103053,7 +104936,8 @@
   void *pUserData,
   void (*xFunc)(sqlite3_context*,int,sqlite3_value **),
   void (*xStep)(sqlite3_context*,int,sqlite3_value **),
-  void (*xFinal)(sqlite3_context*)
+  void (*xFinal)(sqlite3_context*),
+  FuncDestructor *pDestructor
 ){
   FuncDef *p;
   int nName;
@@ -103081,10 +104965,10 @@
   }else if( enc==SQLITE_ANY ){
     int rc;
     rc = sqlite3CreateFunc(db, zFunctionName, nArg, SQLITE_UTF8,
-         pUserData, xFunc, xStep, xFinal);
+         pUserData, xFunc, xStep, xFinal, pDestructor);
     if( rc==SQLITE_OK ){
       rc = sqlite3CreateFunc(db, zFunctionName, nArg, SQLITE_UTF16LE,
-          pUserData, xFunc, xStep, xFinal);
+          pUserData, xFunc, xStep, xFinal, pDestructor);
     }
     if( rc!=SQLITE_OK ){
       return rc;
@@ -103117,6 +105001,15 @@
   if( !p ){
     return SQLITE_NOMEM;
   }
+
+  /* If an older version of the function with a configured destructor is
+  ** being replaced invoke the destructor function here. */
+  functionDestroy(db, p);
+
+  if( pDestructor ){
+    pDestructor->nRef++;
+  }
+  p->pDestructor = pDestructor;
   p->flags = 0;
   p->xFunc = xFunc;
   p->xStep = xStep;
@@ -103131,7 +105024,7 @@
 */
 SQLITE_API int sqlite3_create_function(
   sqlite3 *db,
-  const char *zFunctionName,
+  const char *zFunc,
   int nArg,
   int enc,
   void *p,
@@ -103139,9 +105032,41 @@
   void (*xStep)(sqlite3_context*,int,sqlite3_value **),
   void (*xFinal)(sqlite3_context*)
 ){
-  int rc;
+  return sqlite3_create_function_v2(db, zFunc, nArg, enc, p, xFunc, xStep,
+                                    xFinal, 0);
+}
+
+SQLITE_API int sqlite3_create_function_v2(
+  sqlite3 *db,
+  const char *zFunc,
+  int nArg,
+  int enc,
+  void *p,
+  void (*xFunc)(sqlite3_context*,int,sqlite3_value **),
+  void (*xStep)(sqlite3_context*,int,sqlite3_value **),
+  void (*xFinal)(sqlite3_context*),
+  void (*xDestroy)(void *)
+){
+  int rc = SQLITE_ERROR;
+  FuncDestructor *pArg = 0;
   sqlite3_mutex_enter(db->mutex);
-  rc = sqlite3CreateFunc(db, zFunctionName, nArg, enc, p, xFunc, xStep, xFinal);
+  if( xDestroy ){
+    pArg = (FuncDestructor *)sqlite3DbMallocZero(db, sizeof(FuncDestructor));
+    if( !pArg ){
+      xDestroy(p);
+      goto out;
+    }
+    pArg->xDestroy = xDestroy;
+    pArg->pUserData = p;
+  }
+  rc = sqlite3CreateFunc(db, zFunc, nArg, enc, p, xFunc, xStep, xFinal, pArg);
+  if( pArg && pArg->nRef==0 ){
+    assert( rc!=SQLITE_OK );
+    xDestroy(p);
+    sqlite3DbFree(db, pArg);
+  }
+
+ out:
   rc = sqlite3ApiExit(db, rc);
   sqlite3_mutex_leave(db->mutex);
   return rc;
@@ -103163,7 +105088,7 @@
   sqlite3_mutex_enter(db->mutex);
   assert( !db->mallocFailed );
   zFunc8 = sqlite3Utf16to8(db, zFunctionName, -1, SQLITE_UTF16NATIVE);
-  rc = sqlite3CreateFunc(db, zFunc8, nArg, eTextRep, p, xFunc, xStep, xFinal);
+  rc = sqlite3CreateFunc(db, zFunc8, nArg, eTextRep, p, xFunc, xStep, xFinal,0);
   sqlite3DbFree(db, zFunc8);
   rc = sqlite3ApiExit(db, rc);
   sqlite3_mutex_leave(db->mutex);
@@ -103194,7 +105119,7 @@
   sqlite3_mutex_enter(db->mutex);
   if( sqlite3FindFunction(db, zName, nName, nArg, SQLITE_UTF8, 0)==0 ){
     sqlite3CreateFunc(db, zName, nArg, SQLITE_UTF8,
-                      0, sqlite3InvalidFunction, 0, 0);
+                      0, sqlite3InvalidFunction, 0, 0, 0);
   }
   rc = sqlite3ApiExit(db, SQLITE_OK);
   sqlite3_mutex_leave(db->mutex);
@@ -103332,7 +105257,10 @@
 ** configured by this function.
 */
 SQLITE_API int sqlite3_wal_autocheckpoint(sqlite3 *db, int nFrame){
-#ifndef SQLITE_OMIT_WAL
+#ifdef SQLITE_OMIT_WAL
+  UNUSED_PARAMETER(db);
+  UNUSED_PARAMETER(nFrame);
+#else
   if( nFrame>0 ){
     sqlite3_wal_hook(db, sqlite3WalDefaultHook, SQLITE_INT_TO_PTR(nFrame));
   }else{
@@ -103420,16 +105348,7 @@
 
   for(i=0; i<db->nDb && rc==SQLITE_OK; i++){
     if( i==iDb || iDb==SQLITE_MAX_ATTACHED ){
-      Btree *pBt = db->aDb[i].pBt;
-      if( pBt ){
-        if( sqlite3BtreeIsInReadTrans(pBt) ){
-          rc = SQLITE_LOCKED;
-        }else{
-          sqlite3BtreeEnter(pBt);
-          rc = sqlite3PagerCheckpoint(sqlite3BtreePager(pBt));
-          sqlite3BtreeLeave(pBt);
-        }
-      }
+      rc = sqlite3BtreeCheckpoint(db->aDb[i].pBt);
     }
   }
 
@@ -103472,60 +105391,6 @@
 }
 
 /*
-** This routine is called to create a connection to a database BTree
-** driver.  If zFilename is the name of a file, then that file is
-** opened and used.  If zFilename is the magic name ":memory:" then
-** the database is stored in memory (and is thus forgotten as soon as
-** the connection is closed.)  If zFilename is NULL then the database
-** is a "virtual" database for transient use only and is deleted as
-** soon as the connection is closed.
-**
-** A virtual database can be either a disk file (that is automatically
-** deleted when the file is closed) or it an be held entirely in memory.
-** The sqlite3TempInMemory() function is used to determine which.
-*/
-SQLITE_PRIVATE int sqlite3BtreeFactory(
-  sqlite3 *db,              /* Main database when opening aux otherwise 0 */
-  const char *zFilename,    /* Name of the file containing the BTree database */
-  int omitJournal,          /* if TRUE then do not journal this file */
-  int nCache,               /* How many pages in the page cache */
-  int vfsFlags,             /* Flags passed through to vfsOpen */
-  Btree **ppBtree           /* Pointer to new Btree object written here */
-){
-  int btFlags = 0;
-  int rc;
-  
-  assert( sqlite3_mutex_held(db->mutex) );
-  assert( ppBtree != 0);
-  if( omitJournal ){
-    btFlags |= BTREE_OMIT_JOURNAL;
-  }
-  if( db->flags & SQLITE_NoReadlock ){
-    btFlags |= BTREE_NO_READLOCK;
-  }
-#ifndef SQLITE_OMIT_MEMORYDB
-  if( zFilename==0 && sqlite3TempInMemory(db) ){
-    zFilename = ":memory:";
-  }
-#endif
-
-  if( (vfsFlags & SQLITE_OPEN_MAIN_DB)!=0 && (zFilename==0 || *zFilename==0) ){
-    vfsFlags = (vfsFlags & ~SQLITE_OPEN_MAIN_DB) | SQLITE_OPEN_TEMP_DB;
-  }
-  rc = sqlite3BtreeOpen(zFilename, (sqlite3 *)db, ppBtree, btFlags, vfsFlags);
-
-  /* If the B-Tree was successfully opened, set the pager-cache size to the
-  ** default value. Except, if the call to BtreeOpen() returned a handle
-  ** open on an existing shared pager-cache, do not change the pager-cache 
-  ** size.
-  */
-  if( rc==SQLITE_OK && 0==sqlite3BtreeSchema(*ppBtree, 0, 0) ){
-    sqlite3BtreeSetCacheSize(*ppBtree, nCache);
-  }
-  return rc;
-}
-
-/*
 ** Return UTF-8 encoded English language explanation of the most recent
 ** error.
 */
@@ -103767,17 +105632,39 @@
 */
 SQLITE_API int sqlite3_limit(sqlite3 *db, int limitId, int newLimit){
   int oldLimit;
+
+
+  /* EVIDENCE-OF: R-30189-54097 For each limit category SQLITE_LIMIT_NAME
+  ** there is a hard upper bound set at compile-time by a C preprocessor
+  ** macro called SQLITE_MAX_NAME. (The "_LIMIT_" in the name is changed to
+  ** "_MAX_".)
+  */
+  assert( aHardLimit[SQLITE_LIMIT_LENGTH]==SQLITE_MAX_LENGTH );
+  assert( aHardLimit[SQLITE_LIMIT_SQL_LENGTH]==SQLITE_MAX_SQL_LENGTH );
+  assert( aHardLimit[SQLITE_LIMIT_COLUMN]==SQLITE_MAX_COLUMN );
+  assert( aHardLimit[SQLITE_LIMIT_EXPR_DEPTH]==SQLITE_MAX_EXPR_DEPTH );
+  assert( aHardLimit[SQLITE_LIMIT_COMPOUND_SELECT]==SQLITE_MAX_COMPOUND_SELECT);
+  assert( aHardLimit[SQLITE_LIMIT_VDBE_OP]==SQLITE_MAX_VDBE_OP );
+  assert( aHardLimit[SQLITE_LIMIT_FUNCTION_ARG]==SQLITE_MAX_FUNCTION_ARG );
+  assert( aHardLimit[SQLITE_LIMIT_ATTACHED]==SQLITE_MAX_ATTACHED );
+  assert( aHardLimit[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]==
+                                               SQLITE_MAX_LIKE_PATTERN_LENGTH );
+  assert( aHardLimit[SQLITE_LIMIT_VARIABLE_NUMBER]==SQLITE_MAX_VARIABLE_NUMBER);
+  assert( aHardLimit[SQLITE_LIMIT_TRIGGER_DEPTH]==SQLITE_MAX_TRIGGER_DEPTH );
+  assert( SQLITE_LIMIT_TRIGGER_DEPTH==(SQLITE_N_LIMIT-1) );
+
+
   if( limitId<0 || limitId>=SQLITE_N_LIMIT ){
     return -1;
   }
   oldLimit = db->aLimit[limitId];
-  if( newLimit>=0 ){
+  if( newLimit>=0 ){                   /* IMP: R-52476-28732 */
     if( newLimit>aHardLimit[limitId] ){
-      newLimit = aHardLimit[limitId];
+      newLimit = aHardLimit[limitId];  /* IMP: R-51463-25634 */
     }
     db->aLimit[limitId] = newLimit;
   }
-  return oldLimit;
+  return oldLimit;                     /* IMP: R-53341-35419 */
 }
 
 /*
@@ -103801,6 +105688,24 @@
   if( rc ) return rc;
 #endif
 
+  /* Only allow sensible combinations of bits in the flags argument.  
+  ** Throw an error if any non-sense combination is used.  If we
+  ** do not block illegal combinations here, it could trigger
+  ** assert() statements in deeper layers.  Sensible combinations
+  ** are:
+  **
+  **  1:  SQLITE_OPEN_READONLY
+  **  2:  SQLITE_OPEN_READWRITE
+  **  6:  SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE
+  */
+  assert( SQLITE_OPEN_READONLY  == 0x01 );
+  assert( SQLITE_OPEN_READWRITE == 0x02 );
+  assert( SQLITE_OPEN_CREATE    == 0x04 );
+  testcase( (1<<(flags&7))==0x02 ); /* READONLY */
+  testcase( (1<<(flags&7))==0x04 ); /* READWRITE */
+  testcase( (1<<(flags&7))==0x40 ); /* READWRITE | CREATE */
+  if( ((1<<(flags&7)) & 0x46)==0 ) return SQLITE_MISUSE;
+
   if( sqlite3GlobalConfig.bCoreMutex==0 ){
     isThreadsafe = 0;
   }else if( flags & SQLITE_OPEN_NOMUTEX ){
@@ -103834,7 +105739,8 @@
                SQLITE_OPEN_SUBJOURNAL | 
                SQLITE_OPEN_MASTER_JOURNAL |
                SQLITE_OPEN_NOMUTEX |
-               SQLITE_OPEN_FULLMUTEX
+               SQLITE_OPEN_FULLMUTEX |
+               SQLITE_OPEN_WAL
              );
 
   /* Allocate the sqlite data structure */
@@ -103906,9 +105812,8 @@
 
   /* Open the backend database driver */
   db->openFlags = flags;
-  rc = sqlite3BtreeFactory(db, zFilename, 0, SQLITE_DEFAULT_CACHE_SIZE, 
-                           flags | SQLITE_OPEN_MAIN_DB,
-                           &db->aDb[0].pBt);
+  rc = sqlite3BtreeOpen(zFilename, db, &db->aDb[0].pBt, 0,
+                        flags | SQLITE_OPEN_MAIN_DB);
   if( rc!=SQLITE_OK ){
     if( rc==SQLITE_IOERR_NOMEM ){
       rc = SQLITE_NOMEM;
@@ -104630,6 +106535,22 @@
       break;
     }
 
+    /* sqlite3_test_control(SQLITE_TESTCTRL_SCRATCHMALLOC, sz, &pNew, pFree);
+    **
+    ** Pass pFree into sqlite3ScratchFree(). 
+    ** If sz>0 then allocate a scratch buffer into pNew.  
+    */
+    case SQLITE_TESTCTRL_SCRATCHMALLOC: {
+      void *pFree, **ppNew;
+      int sz;
+      sz = va_arg(ap, int);
+      ppNew = va_arg(ap, void**);
+      pFree = va_arg(ap, void*);
+      if( sz ) *ppNew = sqlite3ScratchMalloc(sz);
+      sqlite3ScratchFree(pFree);
+      break;
+    }
+
   }
   va_end(ap);
 #endif /* SQLITE_OMIT_BUILTIN_TEST */
@@ -104893,7 +106814,7 @@
       assert( aArg==aDyn || (aDyn==0 && aArg==aStatic) );
       assert( nArg<=(int)ArraySize(aStatic) || aArg==aDyn );
       if( (!aDyn && nArg==(int)ArraySize(aStatic))
-       || (aDyn && nArg==(int)(sqlite3DbMallocSize(db, aDyn)/sizeof(void*)))
+       || (aDyn && nArg==(int)(sqlite3MallocSize(aDyn)/sizeof(void*)))
       ){
         /* The aArg[] array needs to grow. */
         void **pNew = (void **)sqlite3Malloc(nArg*sizeof(void *)*2);
@@ -105818,6 +107739,7 @@
 SQLITE_PRIVATE int sqlite3Fts3AllSegdirs(Fts3Table*, sqlite3_stmt **);
 SQLITE_PRIVATE int sqlite3Fts3MatchinfoDocsizeLocal(Fts3Cursor*, u32*);
 SQLITE_PRIVATE int sqlite3Fts3MatchinfoDocsizeGlobal(Fts3Cursor*, u32*);
+SQLITE_PRIVATE int sqlite3Fts3ReadLock(Fts3Table *);
 
 /* Flags allowed as part of the 4th argument to SegmentReaderIterate() */
 #define FTS3_SEGMENT_REQUIRE_POS   0x00000001
@@ -107185,11 +109107,59 @@
 typedef struct TermSelect TermSelect;
 struct TermSelect {
   int isReqPos;
-  char *aOutput;                  /* Malloc'd output buffer */
-  int nOutput;                    /* Size of output in bytes */
+  char *aaOutput[16];             /* Malloc'd output buffer */
+  int anOutput[16];               /* Size of output in bytes */
 };
 
 /*
+** Merge all doclists in the TermSelect.aaOutput[] array into a single
+** doclist stored in TermSelect.aaOutput[0]. If successful, delete all
+** other doclists (except the aaOutput[0] one) and return SQLITE_OK.
+**
+** If an OOM error occurs, return SQLITE_NOMEM. In this case it is
+** the responsibility of the caller to free any doclists left in the
+** TermSelect.aaOutput[] array.
+*/
+static int fts3TermSelectMerge(TermSelect *pTS){
+  int mergetype = (pTS->isReqPos ? MERGE_POS_OR : MERGE_OR);
+  char *aOut = 0;
+  int nOut = 0;
+  int i;
+
+  /* Loop through the doclists in the aaOutput[] array. Merge them all
+  ** into a single doclist.
+  */
+  for(i=0; i<SizeofArray(pTS->aaOutput); i++){
+    if( pTS->aaOutput[i] ){
+      if( !aOut ){
+        aOut = pTS->aaOutput[i];
+        nOut = pTS->anOutput[i];
+        pTS->aaOutput[0] = 0;
+      }else{
+        int nNew = nOut + pTS->anOutput[i];
+        char *aNew = sqlite3_malloc(nNew);
+        if( !aNew ){
+          sqlite3_free(aOut);
+          return SQLITE_NOMEM;
+        }
+        fts3DoclistMerge(mergetype, 0, 0,
+            aNew, &nNew, pTS->aaOutput[i], pTS->anOutput[i], aOut, nOut
+        );
+        sqlite3_free(pTS->aaOutput[i]);
+        sqlite3_free(aOut);
+        pTS->aaOutput[i] = 0;
+        aOut = aNew;
+        nOut = nNew;
+      }
+    }
+  }
+
+  pTS->aaOutput[0] = aOut;
+  pTS->anOutput[0] = nOut;
+  return SQLITE_OK;
+}
+
+/*
 ** This function is used as the sqlite3Fts3SegReaderIterate() callback when
 ** querying the full-text index for a doclist associated with a term or
 ** term-prefix.
@@ -107203,38 +109173,63 @@
   int nDoclist
 ){
   TermSelect *pTS = (TermSelect *)pContext;
-  int nNew = pTS->nOutput + nDoclist;
-  char *aNew = sqlite3_malloc(nNew);
 
   UNUSED_PARAMETER(p);
   UNUSED_PARAMETER(zTerm);
   UNUSED_PARAMETER(nTerm);
 
-  if( !aNew ){
-    return SQLITE_NOMEM;
-  }
-
-  if( pTS->nOutput==0 ){
+  if( pTS->aaOutput[0]==0 ){
     /* If this is the first term selected, copy the doclist to the output
     ** buffer using memcpy(). TODO: Add a way to transfer control of the
     ** aDoclist buffer from the caller so as to avoid the memcpy().
     */
-    memcpy(aNew, aDoclist, nDoclist);
+    pTS->aaOutput[0] = sqlite3_malloc(nDoclist);
+    pTS->anOutput[0] = nDoclist;
+    if( pTS->aaOutput[0] ){
+      memcpy(pTS->aaOutput[0], aDoclist, nDoclist);
+    }else{
+      return SQLITE_NOMEM;
+    }
   }else{
-    /* The output buffer is not empty. Merge doclist aDoclist with the
-    ** existing output. This can only happen with prefix-searches (as
-    ** searches for exact terms return exactly one doclist).
-    */
     int mergetype = (pTS->isReqPos ? MERGE_POS_OR : MERGE_OR);
-    fts3DoclistMerge(mergetype, 0, 0,
-        aNew, &nNew, pTS->aOutput, pTS->nOutput, aDoclist, nDoclist
-    );
+    char *aMerge = aDoclist;
+    int nMerge = nDoclist;
+    int iOut;
+
+    for(iOut=0; iOut<SizeofArray(pTS->aaOutput); iOut++){
+      char *aNew;
+      int nNew;
+      if( pTS->aaOutput[iOut]==0 ){
+        assert( iOut>0 );
+        pTS->aaOutput[iOut] = aMerge;
+        pTS->anOutput[iOut] = nMerge;
+        break;
+      }
+
+      nNew = nMerge + pTS->anOutput[iOut];
+      aNew = sqlite3_malloc(nNew);
+      if( !aNew ){
+        if( aMerge!=aDoclist ){
+          sqlite3_free(aMerge);
+        }
+        return SQLITE_NOMEM;
+      }
+      fts3DoclistMerge(mergetype, 0, 0,
+          aNew, &nNew, pTS->aaOutput[iOut], pTS->anOutput[iOut], aMerge, nMerge
+      );
+
+      if( iOut>0 ) sqlite3_free(aMerge);
+      sqlite3_free(pTS->aaOutput[iOut]);
+      pTS->aaOutput[iOut] = 0;
+
+      aMerge = aNew;
+      nMerge = nNew;
+      if( (iOut+1)==SizeofArray(pTS->aaOutput) ){
+        pTS->aaOutput[iOut] = aMerge;
+        pTS->anOutput[iOut] = nMerge;
+      }
+    }
   }
-
-  sqlite3_free(pTS->aOutput);
-  pTS->aOutput = aNew;
-  pTS->nOutput = nNew;
-
   return SQLITE_OK;
 }
 
@@ -107358,12 +109353,17 @@
   rc = sqlite3Fts3SegReaderIterate(p, apSegment, nSegment, &filter,
       fts3TermSelectCb, (void *)&tsc
   );
+  if( rc==SQLITE_OK ){
+    rc = fts3TermSelectMerge(&tsc);
+  }
 
   if( rc==SQLITE_OK ){
-    *ppOut = tsc.aOutput;
-    *pnOut = tsc.nOutput;
+    *ppOut = tsc.aaOutput[0];
+    *pnOut = tsc.anOutput[0];
   }else{
-    sqlite3_free(tsc.aOutput);
+    for(i=0; i<SizeofArray(tsc.aaOutput); i++){
+      sqlite3_free(tsc.aaOutput[i]);
+    }
   }
 
 finished:
@@ -107689,6 +109689,9 @@
       return rc;
     }
 
+    rc = sqlite3Fts3ReadLock(p);
+    if( rc!=SQLITE_OK ) return rc;
+
     rc = evalFts3Expr(p, pCsr->pExpr, &pCsr->aDoclist, &pCsr->nDoclist, 0);
     pCsr->pNextId = pCsr->aDoclist;
     pCsr->iPrevId = 0;
@@ -108067,11 +110070,14 @@
   const char *zName               /* New name of table */
 ){
   Fts3Table *p = (Fts3Table *)pVtab;
-  sqlite3 *db;                    /* Database connection */
+  sqlite3 *db = p->db;            /* Database connection */
   int rc;                         /* Return Code */
- 
-  db = p->db;
-  rc = SQLITE_OK;
+
+  rc = sqlite3Fts3PendingTermsFlush(p);
+  if( rc!=SQLITE_OK ){
+    return rc;
+  }
+
   fts3DbExec(&rc, db,
     "ALTER TABLE %Q.'%q_content'  RENAME TO '%q_content';",
     p->zDb, p->zName, zName
@@ -108139,7 +110145,7 @@
 ** used to retrieve the respective implementations.
 **
 ** Calling sqlite3Fts3SimpleTokenizerModule() sets the value pointed
-** to by the argument to point a the "simple" tokenizer implementation.
+** to by the argument to point to the "simple" tokenizer implementation.
 ** Function ...PorterTokenizerModule() sets *pModule to point to the
 ** porter tokenizer/stemmer implementation.
 */
@@ -108344,7 +110350,7 @@
 ** negative values).
 */
 static int fts3isspace(char c){
-  return (c&0x80)==0 ? isspace(c) : 0;
+  return c==' ' || c=='\t' || c=='\n' || c=='\r' || c=='\v' || c=='\f';
 }
 
 /*
@@ -110731,6 +112737,9 @@
 static int simpleDelim(simple_tokenizer *t, unsigned char c){
   return c<0x80 && t->delim[c];
 }
+static int fts3_isalnum(int x){
+  return (x>='0' && x<='9') || (x>='A' && x<='Z') || (x>='a' && x<='z');
+}
 
 /*
 ** Create a new tokenizer instance.
@@ -110765,7 +112774,7 @@
     /* Mark non-alphanumeric ASCII characters as delimiters */
     int i;
     for(i=1; i<0x80; i++){
-      t->delim[i] = !isalnum(i) ? -1 : 0;
+      t->delim[i] = !fts3_isalnum(i) ? -1 : 0;
     }
   }
 
@@ -110871,7 +112880,7 @@
         ** case-insensitivity.
         */
         unsigned char ch = p[iStartOffset+i];
-        c->pToken[i] = (char)(ch<0x80 ? tolower(ch) : ch);
+        c->pToken[i] = (char)((ch>='A' && ch<='Z') ? ch-'A'+'a' : ch);
       }
       *ppToken = c->pToken;
       *pnBytes = n;
@@ -111232,6 +113241,36 @@
 }
 
 /*
+** This function ensures that the caller has obtained a shared-cache
+** table-lock on the %_content table. This is required before reading
+** data from the fts3 table. If this lock is not acquired first, then
+** the caller may end up holding read-locks on the %_segments and %_segdir
+** tables, but no read-lock on the %_content table. If this happens 
+** a second connection will be able to write to the fts3 table, but
+** attempting to commit those writes might return SQLITE_LOCKED or
+** SQLITE_LOCKED_SHAREDCACHE (because the commit attempts to obtain 
+** write-locks on the %_segments and %_segdir ** tables). 
+**
+** We try to avoid this because if FTS3 returns any error when committing
+** a transaction, the whole transaction will be rolled back. And this is
+** not what users expect when they get SQLITE_LOCKED_SHAREDCACHE. It can
+** still happen if the user reads data directly from the %_segments or
+** %_segdir tables instead of going through FTS3 though.
+*/
+SQLITE_PRIVATE int sqlite3Fts3ReadLock(Fts3Table *p){
+  int rc;                         /* Return code */
+  sqlite3_stmt *pStmt;            /* Statement used to obtain lock */
+
+  rc = fts3SqlStmt(p, SQL_SELECT_CONTENT_BY_ROWID, &pStmt, 0);
+  if( rc==SQLITE_OK ){
+    sqlite3_bind_null(pStmt, 1);
+    sqlite3_step(pStmt);
+    rc = sqlite3_reset(pStmt);
+  }
+  return rc;
+}
+
+/*
 ** Set *ppStmt to a statement handle that may be used to iterate through
 ** all rows in the %_segdir table, from oldest to newest. If successful,
 ** return SQLITE_OK. If an error occurs while preparing the statement, 
@@ -114722,6 +116761,45 @@
 ** algorithms packaged as an SQLite virtual table module.
 */
 
+/*
+** Database Format of R-Tree Tables
+** --------------------------------
+**
+** The data structure for a single virtual r-tree table is stored in three 
+** native SQLite tables declared as follows. In each case, the '%' character
+** in the table name is replaced with the user-supplied name of the r-tree
+** table.
+**
+**   CREATE TABLE %_node(nodeno INTEGER PRIMARY KEY, data BLOB)
+**   CREATE TABLE %_parent(nodeno INTEGER PRIMARY KEY, parentnode INTEGER)
+**   CREATE TABLE %_rowid(rowid INTEGER PRIMARY KEY, nodeno INTEGER)
+**
+** The data for each node of the r-tree structure is stored in the %_node
+** table. For each node that is not the root node of the r-tree, there is
+** an entry in the %_parent table associating the node with its parent.
+** And for each row of data in the table, there is an entry in the %_rowid
+** table that maps from the entries rowid to the id of the node that it
+** is stored on.
+**
+** The root node of an r-tree always exists, even if the r-tree table is
+** empty. The nodeno of the root node is always 1. All other nodes in the
+** table must be the same size as the root node. The content of each node
+** is formatted as follows:
+**
+**   1. If the node is the root node (node 1), then the first 2 bytes
+**      of the node contain the tree depth as a big-endian integer.
+**      For non-root nodes, the first 2 bytes are left unused.
+**
+**   2. The next 2 bytes contain the number of entries currently 
+**      stored in the node.
+**
+**   3. The remainder of the node contains the node entries. Each entry
+**      consists of a single 8-byte integer followed by an even number
+**      of 4-byte coordinates. For leaf nodes the integer is the rowid
+**      of a record. For internal nodes it is the node number of a
+**      child page.
+*/
+
 #if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_RTREE)
 
 /*
@@ -114762,6 +116840,9 @@
   #define AssignCells splitNodeStartree
 #endif
 
+#if !defined(NDEBUG) && !defined(SQLITE_DEBUG) 
+# define NDEBUG 1
+#endif
 
 #ifndef SQLITE_CORE
   SQLITE_EXTENSION_INIT1
@@ -114770,6 +116851,7 @@
 
 
 #ifndef SQLITE_AMALGAMATION
+#include "sqlite3rtree.h"
 typedef sqlite3_int64 i64;
 typedef unsigned char u8;
 typedef unsigned int u32;
@@ -114780,6 +116862,8 @@
 typedef struct RtreeNode RtreeNode;
 typedef struct RtreeCell RtreeCell;
 typedef struct RtreeConstraint RtreeConstraint;
+typedef struct RtreeMatchArg RtreeMatchArg;
+typedef struct RtreeGeomCallback RtreeGeomCallback;
 typedef union RtreeCoord RtreeCoord;
 
 /* The rtree may have between 1 and RTREE_MAX_DIMENSIONS dimensions. */
@@ -114849,6 +116933,15 @@
 #define RTREE_REINSERT(p) RTREE_MINCELLS(p)
 #define RTREE_MAXCELLS 51
 
+/*
+** The smallest possible node-size is (512-64)==448 bytes. And the largest
+** supported cell size is 48 bytes (8 byte rowid + ten 4 byte coordinates).
+** Therefore all non-root nodes must contain at least 3 entries. Since 
+** 2^40 is greater than 2^64, an r-tree structure always has a depth of
+** 40 or less.
+*/
+#define RTREE_MAX_DEPTH 40
+
 /* 
 ** An rtree cursor object.
 */
@@ -114881,35 +116974,23 @@
 ** A search constraint.
 */
 struct RtreeConstraint {
-  int iCoord;                       /* Index of constrained coordinate */
-  int op;                           /* Constraining operation */
-  double rValue;                    /* Constraint value. */
+  int iCoord;                     /* Index of constrained coordinate */
+  int op;                         /* Constraining operation */
+  double rValue;                  /* Constraint value. */
+  int (*xGeom)(sqlite3_rtree_geometry *, int, double *, int *);
+  sqlite3_rtree_geometry *pGeom;  /* Constraint callback argument for a MATCH */
 };
 
 /* Possible values for RtreeConstraint.op */
-#define RTREE_EQ 0x41
-#define RTREE_LE 0x42
-#define RTREE_LT 0x43
-#define RTREE_GE 0x44
-#define RTREE_GT 0x45
+#define RTREE_EQ    0x41
+#define RTREE_LE    0x42
+#define RTREE_LT    0x43
+#define RTREE_GE    0x44
+#define RTREE_GT    0x45
+#define RTREE_MATCH 0x46
 
 /* 
 ** An rtree structure node.
-**
-** Data format (RtreeNode.zData):
-**
-**   1. If the node is the root node (node 1), then the first 2 bytes
-**      of the node contain the tree depth as a big-endian integer.
-**      For non-root nodes, the first 2 bytes are left unused.
-**
-**   2. The next 2 bytes contain the number of entries currently 
-**      stored in the node.
-**
-**   3. The remainder of the node contains the node entries. Each entry
-**      consists of a single 8-byte integer followed by an even number
-**      of 4-byte coordinates. For leaf nodes the integer is the rowid
-**      of a record. For internal nodes it is the node number of a
-**      child page.
 */
 struct RtreeNode {
   RtreeNode *pParent;               /* Parent node */
@@ -114929,6 +117010,40 @@
   RtreeCoord aCoord[RTREE_MAX_DIMENSIONS*2];
 };
 
+
+/*
+** Value for the first field of every RtreeMatchArg object. The MATCH
+** operator tests that the first field of a blob operand matches this
+** value to avoid operating on invalid blobs (which could cause a segfault).
+*/
+#define RTREE_GEOMETRY_MAGIC 0x891245AB
+
+/*
+** An instance of this structure must be supplied as a blob argument to
+** the right-hand-side of an SQL MATCH operator used to constrain an
+** r-tree query.
+*/
+struct RtreeMatchArg {
+  u32 magic;                      /* Always RTREE_GEOMETRY_MAGIC */
+  int (*xGeom)(sqlite3_rtree_geometry *, int, double *, int *);
+  void *pContext;
+  int nParam;
+  double aParam[1];
+};
+
+/*
+** When a geometry callback is created (see sqlite3_rtree_geometry_callback),
+** a single instance of the following structure is allocated. It is used
+** as the context for the user-function created by by s_r_g_c(). The object
+** is eventually deleted by the destructor mechanism provided by
+** sqlite3_create_function_v2() (which is called by s_r_g_c() to create
+** the geometry callback function).
+*/
+struct RtreeGeomCallback {
+  int (*xGeom)(sqlite3_rtree_geometry *, int, double *, int *);
+  void *pContext;
+};
+
 #ifndef MAX
 # define MAX(x,y) ((x) < (y) ? (y) : (x))
 #endif
@@ -115011,10 +117126,8 @@
 ** Clear the content of node p (set all bytes to 0x00).
 */
 static void nodeZero(Rtree *pRtree, RtreeNode *p){
-  if( p ){
-    memset(&p->zData[2], 0, pRtree->iNodeSize-2);
-    p->isDirty = 1;
-  }
+  memset(&p->zData[2], 0, pRtree->iNodeSize-2);
+  p->isDirty = 1;
 }
 
 /*
@@ -115034,7 +117147,6 @@
 */
 static RtreeNode *nodeHashLookup(Rtree *pRtree, i64 iNode){
   RtreeNode *p;
-  assert( iNode!=0 );
   for(p=pRtree->aHash[nodeHash(iNode)]; p && p->iNode!=iNode; p=p->pNext);
   return p;
 }
@@ -115043,13 +117155,11 @@
 ** Add node pNode to the node hash table.
 */
 static void nodeHashInsert(Rtree *pRtree, RtreeNode *pNode){
-  if( pNode ){
-    int iHash;
-    assert( pNode->pNext==0 );
-    iHash = nodeHash(pNode->iNode);
-    pNode->pNext = pRtree->aHash[iHash];
-    pRtree->aHash[iHash] = pNode;
-  }
+  int iHash;
+  assert( pNode->pNext==0 );
+  iHash = nodeHash(pNode->iNode);
+  pNode->pNext = pRtree->aHash[iHash];
+  pRtree->aHash[iHash] = pNode;
 }
 
 /*
@@ -115071,11 +117181,11 @@
 ** assigned a node number when nodeWrite() is called to write the
 ** node contents out to the database.
 */
-static RtreeNode *nodeNew(Rtree *pRtree, RtreeNode *pParent, int zero){
+static RtreeNode *nodeNew(Rtree *pRtree, RtreeNode *pParent){
   RtreeNode *pNode;
   pNode = (RtreeNode *)sqlite3_malloc(sizeof(RtreeNode) + pRtree->iNodeSize);
   if( pNode ){
-    memset(pNode, 0, sizeof(RtreeNode) + (zero?pRtree->iNodeSize:0));
+    memset(pNode, 0, sizeof(RtreeNode) + pRtree->iNodeSize);
     pNode->zData = (u8 *)&pNode[1];
     pNode->nRef = 1;
     pNode->pParent = pParent;
@@ -115096,6 +117206,7 @@
   RtreeNode **ppNode         /* OUT: Acquired node */
 ){
   int rc;
+  int rc2 = SQLITE_OK;
   RtreeNode *pNode;
 
   /* Check if the requested node is already in the hash table. If so,
@@ -115112,40 +117223,64 @@
     return SQLITE_OK;
   }
 
-  pNode = (RtreeNode *)sqlite3_malloc(sizeof(RtreeNode) + pRtree->iNodeSize);
-  if( !pNode ){
-    *ppNode = 0;
-    return SQLITE_NOMEM;
-  }
-  pNode->pParent = pParent;
-  pNode->zData = (u8 *)&pNode[1];
-  pNode->nRef = 1;
-  pNode->iNode = iNode;
-  pNode->isDirty = 0;
-  pNode->pNext = 0;
-
   sqlite3_bind_int64(pRtree->pReadNode, 1, iNode);
   rc = sqlite3_step(pRtree->pReadNode);
   if( rc==SQLITE_ROW ){
     const u8 *zBlob = sqlite3_column_blob(pRtree->pReadNode, 0);
-    assert( sqlite3_column_bytes(pRtree->pReadNode, 0)==pRtree->iNodeSize );
-    memcpy(pNode->zData, zBlob, pRtree->iNodeSize);
-    nodeReference(pParent);
+    if( pRtree->iNodeSize==sqlite3_column_bytes(pRtree->pReadNode, 0) ){
+      pNode = (RtreeNode *)sqlite3_malloc(sizeof(RtreeNode)+pRtree->iNodeSize);
+      if( !pNode ){
+        rc2 = SQLITE_NOMEM;
+      }else{
+        pNode->pParent = pParent;
+        pNode->zData = (u8 *)&pNode[1];
+        pNode->nRef = 1;
+        pNode->iNode = iNode;
+        pNode->isDirty = 0;
+        pNode->pNext = 0;
+        memcpy(pNode->zData, zBlob, pRtree->iNodeSize);
+        nodeReference(pParent);
+      }
+    }
+  }
+  rc = sqlite3_reset(pRtree->pReadNode);
+  if( rc==SQLITE_OK ) rc = rc2;
+
+  /* If the root node was just loaded, set pRtree->iDepth to the height
+  ** of the r-tree structure. A height of zero means all data is stored on
+  ** the root node. A height of one means the children of the root node
+  ** are the leaves, and so on. If the depth as specified on the root node
+  ** is greater than RTREE_MAX_DEPTH, the r-tree structure must be corrupt.
+  */
+  if( pNode && iNode==1 ){
+    pRtree->iDepth = readInt16(pNode->zData);
+    if( pRtree->iDepth>RTREE_MAX_DEPTH ){
+      rc = SQLITE_CORRUPT;
+    }
+  }
+
+  /* If no error has occurred so far, check if the "number of entries"
+  ** field on the node is too large. If so, set the return code to 
+  ** SQLITE_CORRUPT.
+  */
+  if( pNode && rc==SQLITE_OK ){
+    if( NCELL(pNode)>((pRtree->iNodeSize-4)/pRtree->nBytesPerCell) ){
+      rc = SQLITE_CORRUPT;
+    }
+  }
+
+  if( rc==SQLITE_OK ){
+    if( pNode!=0 ){
+      nodeHashInsert(pRtree, pNode);
+    }else{
+      rc = SQLITE_CORRUPT;
+    }
+    *ppNode = pNode;
   }else{
     sqlite3_free(pNode);
-    pNode = 0;
+    *ppNode = 0;
   }
 
-  *ppNode = pNode;
-  rc = sqlite3_reset(pRtree->pReadNode);
-
-  if( rc==SQLITE_OK && iNode==1 ){
-    pRtree->iDepth = readInt16(pNode->zData);
-  }
-
-  assert( (rc==SQLITE_OK && pNode) || (pNode==0 && rc!=SQLITE_OK) );
-  nodeHashInsert(pRtree, pNode);
-
   return rc;
 }
 
@@ -115197,8 +117332,7 @@
   nMaxCell = (pRtree->iNodeSize-4)/pRtree->nBytesPerCell;
   nCell = NCELL(pNode);
 
-  assert(nCell<=nMaxCell);
-
+  assert( nCell<=nMaxCell );
   if( nCell<nMaxCell ){
     nodeOverwriteCell(pRtree, pNode, pCell, nCell);
     writeInt16(&pNode->zData[2], nCell+1);
@@ -115418,6 +117552,25 @@
   return rc;
 }
 
+
+/*
+** Free the RtreeCursor.aConstraint[] array and its contents.
+*/
+static void freeCursorConstraints(RtreeCursor *pCsr){
+  if( pCsr->aConstraint ){
+    int i;                        /* Used to iterate through constraint array */
+    for(i=0; i<pCsr->nConstraint; i++){
+      sqlite3_rtree_geometry *pGeom = pCsr->aConstraint[i].pGeom;
+      if( pGeom ){
+        if( pGeom->xDelUser ) pGeom->xDelUser(pGeom->pUser);
+        sqlite3_free(pGeom);
+      }
+    }
+    sqlite3_free(pCsr->aConstraint);
+    pCsr->aConstraint = 0;
+  }
+}
+
 /* 
 ** Rtree virtual table module xClose method.
 */
@@ -115425,7 +117578,7 @@
   Rtree *pRtree = (Rtree *)(cur->pVtab);
   int rc;
   RtreeCursor *pCsr = (RtreeCursor *)cur;
-  sqlite3_free(pCsr->aConstraint);
+  freeCursorConstraints(pCsr);
   rc = nodeRelease(pRtree, pCsr->pNode);
   sqlite3_free(pCsr);
   return rc;
@@ -115442,13 +117595,39 @@
   return (pCsr->pNode==0);
 }
 
+/*
+** The r-tree constraint passed as the second argument to this function is
+** guaranteed to be a MATCH constraint.
+*/
+static int testRtreeGeom(
+  Rtree *pRtree,                  /* R-Tree object */
+  RtreeConstraint *pConstraint,   /* MATCH constraint to test */
+  RtreeCell *pCell,               /* Cell to test */
+  int *pbRes                      /* OUT: Test result */
+){
+  int i;
+  double aCoord[RTREE_MAX_DIMENSIONS*2];
+  int nCoord = pRtree->nDim*2;
+
+  assert( pConstraint->op==RTREE_MATCH );
+  assert( pConstraint->pGeom );
+
+  for(i=0; i<nCoord; i++){
+    aCoord[i] = DCOORD(pCell->aCoord[i]);
+  }
+  return pConstraint->xGeom(pConstraint->pGeom, nCoord, aCoord, pbRes);
+}
+
 /* 
 ** Cursor pCursor currently points to a cell in a non-leaf page.
-** Return true if the sub-tree headed by the cell is filtered
+** Set *pbEof to true if the sub-tree headed by the cell is filtered
 ** (excluded) by the constraints in the pCursor->aConstraint[] 
 ** array, or false otherwise.
+**
+** Return SQLITE_OK if successful or an SQLite error code if an error
+** occurs within a geometry callback.
 */
-static int testRtreeCell(Rtree *pRtree, RtreeCursor *pCursor){
+static int testRtreeCell(Rtree *pRtree, RtreeCursor *pCursor, int *pbEof){
   RtreeCell cell;
   int ii;
   int bRes = 0;
@@ -115460,31 +117639,55 @@
     double cell_max = DCOORD(cell.aCoord[(p->iCoord>>1)*2+1]);
 
     assert(p->op==RTREE_LE || p->op==RTREE_LT || p->op==RTREE_GE 
-        || p->op==RTREE_GT || p->op==RTREE_EQ
+        || p->op==RTREE_GT || p->op==RTREE_EQ || p->op==RTREE_MATCH
     );
 
     switch( p->op ){
-      case RTREE_LE: case RTREE_LT: bRes = p->rValue<cell_min; break;
-      case RTREE_GE: case RTREE_GT: bRes = p->rValue>cell_max; break;
-      case RTREE_EQ: 
+      case RTREE_LE: case RTREE_LT: 
+        bRes = p->rValue<cell_min; 
+        break;
+
+      case RTREE_GE: case RTREE_GT: 
+        bRes = p->rValue>cell_max; 
+        break;
+
+      case RTREE_EQ:
         bRes = (p->rValue>cell_max || p->rValue<cell_min);
         break;
+
+      default: {
+        int rc;
+        assert( p->op==RTREE_MATCH );
+        rc = testRtreeGeom(pRtree, p, &cell, &bRes);
+        if( rc!=SQLITE_OK ){
+          return rc;
+        }
+        bRes = !bRes;
+        break;
+      }
     }
   }
 
-  return bRes;
+  *pbEof = bRes;
+  return SQLITE_OK;
 }
 
 /* 
-** Return true if the cell that cursor pCursor currently points to
+** Test if the cell that cursor pCursor currently points to
 ** would be filtered (excluded) by the constraints in the 
-** pCursor->aConstraint[] array, or false otherwise.
+** pCursor->aConstraint[] array. If so, set *pbEof to true before
+** returning. If the cell is not filtered (excluded) by the constraints,
+** set pbEof to zero.
+**
+** Return SQLITE_OK if successful or an SQLite error code if an error
+** occurs within a geometry callback.
 **
 ** This function assumes that the cell is part of a leaf node.
 */
-static int testRtreeEntry(Rtree *pRtree, RtreeCursor *pCursor){
+static int testRtreeEntry(Rtree *pRtree, RtreeCursor *pCursor, int *pbEof){
   RtreeCell cell;
   int ii;
+  *pbEof = 0;
 
   nodeGetCell(pRtree, pCursor->pNode, pCursor->iCell, &cell);
   for(ii=0; ii<pCursor->nConstraint; ii++){
@@ -115492,7 +117695,7 @@
     double coord = DCOORD(cell.aCoord[p->iCoord]);
     int res;
     assert(p->op==RTREE_LE || p->op==RTREE_LT || p->op==RTREE_GE 
-        || p->op==RTREE_GT || p->op==RTREE_EQ
+        || p->op==RTREE_GT || p->op==RTREE_EQ || p->op==RTREE_MATCH
     );
     switch( p->op ){
       case RTREE_LE: res = (coord<=p->rValue); break;
@@ -115500,12 +117703,24 @@
       case RTREE_GE: res = (coord>=p->rValue); break;
       case RTREE_GT: res = (coord>p->rValue);  break;
       case RTREE_EQ: res = (coord==p->rValue); break;
+      default: {
+        int rc;
+        assert( p->op==RTREE_MATCH );
+        rc = testRtreeGeom(pRtree, p, &cell, &res);
+        if( rc!=SQLITE_OK ){
+          return rc;
+        }
+        break;
+      }
     }
 
-    if( !res ) return 1;
+    if( !res ){
+      *pbEof = 1;
+      return SQLITE_OK;
+    }
   }
 
-  return 0;
+  return SQLITE_OK;
 }
 
 /*
@@ -115532,13 +117747,13 @@
   assert( iHeight>=0 );
 
   if( iHeight==0 ){
-    isEof = testRtreeEntry(pRtree, pCursor);
+    rc = testRtreeEntry(pRtree, pCursor, &isEof);
   }else{
-    isEof = testRtreeCell(pRtree, pCursor);
+    rc = testRtreeCell(pRtree, pCursor, &isEof);
   }
-  if( isEof || iHeight==0 ){
+  if( rc!=SQLITE_OK || isEof || iHeight==0 ){
     *pEof = isEof;
-    return SQLITE_OK;
+    return rc;
   }
 
   iRowid = nodeGetRowid(pRtree, pCursor->pNode, pCursor->iCell);
@@ -115574,24 +117789,34 @@
 ** One of the cells in node pNode is guaranteed to have a 64-bit 
 ** integer value equal to iRowid. Return the index of this cell.
 */
-static int nodeRowidIndex(Rtree *pRtree, RtreeNode *pNode, i64 iRowid){
+static int nodeRowidIndex(
+  Rtree *pRtree, 
+  RtreeNode *pNode, 
+  i64 iRowid,
+  int *piIndex
+){
   int ii;
-  for(ii=0; nodeGetRowid(pRtree, pNode, ii)!=iRowid; ii++){
-    assert( ii<(NCELL(pNode)-1) );
+  int nCell = NCELL(pNode);
+  for(ii=0; ii<nCell; ii++){
+    if( nodeGetRowid(pRtree, pNode, ii)==iRowid ){
+      *piIndex = ii;
+      return SQLITE_OK;
+    }
   }
-  return ii;
+  return SQLITE_CORRUPT;
 }
 
 /*
 ** Return the index of the cell containing a pointer to node pNode
 ** in its parent. If pNode is the root node, return -1.
 */
-static int nodeParentIndex(Rtree *pRtree, RtreeNode *pNode){
+static int nodeParentIndex(Rtree *pRtree, RtreeNode *pNode, int *piIndex){
   RtreeNode *pParent = pNode->pParent;
   if( pParent ){
-    return nodeRowidIndex(pRtree, pParent, pNode->iNode);
+    return nodeRowidIndex(pRtree, pParent, pNode->iNode, piIndex);
   }
-  return -1;
+  *piIndex = -1;
+  return SQLITE_OK;
 }
 
 /* 
@@ -115602,13 +117827,17 @@
   RtreeCursor *pCsr = (RtreeCursor *)pVtabCursor;
   int rc = SQLITE_OK;
 
+  /* RtreeCursor.pNode must not be NULL. If is is NULL, then this cursor is
+  ** already at EOF. It is against the rules to call the xNext() method of
+  ** a cursor that has already reached EOF.
+  */
+  assert( pCsr->pNode );
+
   if( pCsr->iStrategy==1 ){
     /* This "scan" is a direct lookup by rowid. There is no next entry. */
     nodeRelease(pRtree, pCsr->pNode);
     pCsr->pNode = 0;
-  }
-
-  else if( pCsr->pNode ){
+  }else{
     /* Move to the next entry that matches the configured constraints. */
     int iHeight = 0;
     while( pCsr->pNode ){
@@ -115622,7 +117851,10 @@
         }
       }
       pCsr->pNode = pNode->pParent;
-      pCsr->iCell = nodeParentIndex(pRtree, pNode);
+      rc = nodeParentIndex(pRtree, pNode, &pCsr->iCell);
+      if( rc!=SQLITE_OK ){
+        return rc;
+      }
       nodeReference(pCsr->pNode);
       nodeRelease(pRtree, pNode);
       iHeight++;
@@ -115690,6 +117922,51 @@
   return rc;
 }
 
+/*
+** This function is called to configure the RtreeConstraint object passed
+** as the second argument for a MATCH constraint. The value passed as the
+** first argument to this function is the right-hand operand to the MATCH
+** operator.
+*/
+static int deserializeGeometry(sqlite3_value *pValue, RtreeConstraint *pCons){
+  RtreeMatchArg *p;
+  sqlite3_rtree_geometry *pGeom;
+  int nBlob;
+
+  /* Check that value is actually a blob. */
+  if( !sqlite3_value_type(pValue)==SQLITE_BLOB ) return SQLITE_ERROR;
+
+  /* Check that the blob is roughly the right size. */
+  nBlob = sqlite3_value_bytes(pValue);
+  if( nBlob<sizeof(RtreeMatchArg) 
+   || ((nBlob-sizeof(RtreeMatchArg))%sizeof(double))!=0
+  ){
+    return SQLITE_ERROR;
+  }
+
+  pGeom = (sqlite3_rtree_geometry *)sqlite3_malloc(
+      sizeof(sqlite3_rtree_geometry) + nBlob
+  );
+  if( !pGeom ) return SQLITE_NOMEM;
+  memset(pGeom, 0, sizeof(sqlite3_rtree_geometry));
+  p = (RtreeMatchArg *)&pGeom[1];
+
+  memcpy(p, sqlite3_value_blob(pValue), nBlob);
+  if( p->magic!=RTREE_GEOMETRY_MAGIC 
+   || nBlob!=(sizeof(RtreeMatchArg) + (p->nParam-1)*sizeof(double))
+  ){
+    sqlite3_free(pGeom);
+    return SQLITE_ERROR;
+  }
+
+  pGeom->pContext = p->pContext;
+  pGeom->nParam = p->nParam;
+  pGeom->aParam = p->aParam;
+
+  pCons->xGeom = p->xGeom;
+  pCons->pGeom = pGeom;
+  return SQLITE_OK;
+}
 
 /* 
 ** Rtree virtual table module xFilter method.
@@ -115708,8 +117985,7 @@
 
   rtreeReference(pRtree);
 
-  sqlite3_free(pCsr->aConstraint);
-  pCsr->aConstraint = 0;
+  freeCursorConstraints(pCsr);
   pCsr->iStrategy = idxNum;
 
   if( idxNum==1 ){
@@ -115718,8 +117994,9 @@
     i64 iRowid = sqlite3_value_int64(argv[0]);
     rc = findLeafNode(pRtree, iRowid, &pLeaf);
     pCsr->pNode = pLeaf; 
-    if( pLeaf && rc==SQLITE_OK ){
-      pCsr->iCell = nodeRowidIndex(pRtree, pLeaf, iRowid);
+    if( pLeaf ){
+      assert( rc==SQLITE_OK );
+      rc = nodeRowidIndex(pRtree, pLeaf, iRowid, &pCsr->iCell);
     }
   }else{
     /* Normal case - r-tree scan. Set up the RtreeCursor.aConstraint array 
@@ -115731,12 +118008,24 @@
       if( !pCsr->aConstraint ){
         rc = SQLITE_NOMEM;
       }else{
+        memset(pCsr->aConstraint, 0, sizeof(RtreeConstraint)*argc);
         assert( (idxStr==0 && argc==0) || strlen(idxStr)==argc*2 );
         for(ii=0; ii<argc; ii++){
           RtreeConstraint *p = &pCsr->aConstraint[ii];
           p->op = idxStr[ii*2];
           p->iCoord = idxStr[ii*2+1]-'a';
-          p->rValue = sqlite3_value_double(argv[ii]);
+          if( p->op==RTREE_MATCH ){
+            /* A MATCH operator. The right-hand-side must be a blob that
+            ** can be cast into an RtreeMatchArg object. One created using
+            ** an sqlite3_rtree_geometry_callback() SQL user function.
+            */
+            rc = deserializeGeometry(argv[ii], p);
+            if( rc!=SQLITE_OK ){
+              break;
+            }
+          }else{
+            p->rValue = sqlite3_value_double(argv[ii]);
+          }
         }
       }
     }
@@ -115777,11 +118066,10 @@
 **   idxNum     idxStr        Strategy
 **   ------------------------------------------------
 **     1        Unused        Direct lookup by rowid.
-**     2        See below     R-tree query.
-**     3        Unused        Full table scan.
+**     2        See below     R-tree query or full-table scan.
 **   ------------------------------------------------
 **
-** If strategy 1 or 3 is used, then idxStr is not meaningful. If strategy
+** If strategy 1 is used, then idxStr is not meaningful. If strategy
 ** 2 is used, idxStr is formatted to contain 2 bytes for each 
 ** constraint used. The first two bytes of idxStr correspond to 
 ** the constraint in sqlite3_index_info.aConstraintUsage[] with
@@ -115797,6 +118085,7 @@
 **      <        0x43 ('C')
 **     >=        0x44 ('D')
 **      >        0x45 ('E')
+**   MATCH       0x46 ('F')
 **   ----------------------
 **
 ** The second of each pair of bytes identifies the coordinate column
@@ -115835,7 +118124,9 @@
       return SQLITE_OK;
     }
 
-    if( p->usable && p->iColumn>0 ){
+    if( p->usable && (p->iColumn>0 || p->op==SQLITE_INDEX_CONSTRAINT_MATCH) ){
+      int j, opmsk;
+      static const unsigned char compatible[] = { 0, 0, 1, 1, 2, 2 };
       u8 op = 0;
       switch( p->op ){
         case SQLITE_INDEX_CONSTRAINT_EQ: op = RTREE_EQ; break;
@@ -115843,31 +118134,33 @@
         case SQLITE_INDEX_CONSTRAINT_LE: op = RTREE_LE; break;
         case SQLITE_INDEX_CONSTRAINT_LT: op = RTREE_LT; break;
         case SQLITE_INDEX_CONSTRAINT_GE: op = RTREE_GE; break;
+        default:
+          assert( p->op==SQLITE_INDEX_CONSTRAINT_MATCH );
+          op = RTREE_MATCH; 
+          break;
       }
-      if( op ){
-        /* Make sure this particular constraint has not been used before.
-        ** If it has been used before, ignore it.
-        **
-        ** A <= or < can be used if there is a prior >= or >.
-        ** A >= or > can be used if there is a prior < or <=.
-        ** A <= or < is disqualified if there is a prior <=, <, or ==.
-        ** A >= or > is disqualified if there is a prior >=, >, or ==.
-        ** A == is disqualifed if there is any prior constraint.
-        */
-        int j, opmsk;
-        static const unsigned char compatible[] = { 0, 0, 1, 1, 2, 2 };
-        assert( compatible[RTREE_EQ & 7]==0 );
-        assert( compatible[RTREE_LT & 7]==1 );
-        assert( compatible[RTREE_LE & 7]==1 );
-        assert( compatible[RTREE_GT & 7]==2 );
-        assert( compatible[RTREE_GE & 7]==2 );
-        cCol = p->iColumn - 1 + 'a';
-        opmsk = compatible[op & 7];
-        for(j=0; j<iIdx; j+=2){
-          if( zIdxStr[j+1]==cCol && (compatible[zIdxStr[j] & 7] & opmsk)!=0 ){
-            op = 0;
-            break;
-          }
+      assert( op!=0 );
+
+      /* Make sure this particular constraint has not been used before.
+      ** If it has been used before, ignore it.
+      **
+      ** A <= or < can be used if there is a prior >= or >.
+      ** A >= or > can be used if there is a prior < or <=.
+      ** A <= or < is disqualified if there is a prior <=, <, or ==.
+      ** A >= or > is disqualified if there is a prior >=, >, or ==.
+      ** A == is disqualifed if there is any prior constraint.
+      */
+      assert( compatible[RTREE_EQ & 7]==0 );
+      assert( compatible[RTREE_LT & 7]==1 );
+      assert( compatible[RTREE_LE & 7]==1 );
+      assert( compatible[RTREE_GT & 7]==2 );
+      assert( compatible[RTREE_GE & 7]==2 );
+      cCol = p->iColumn - 1 + 'a';
+      opmsk = compatible[op & 7];
+      for(j=0; j<iIdx; j+=2){
+        if( zIdxStr[j+1]==cCol && (compatible[zIdxStr[j] & 7] & opmsk)!=0 ){
+          op = 0;
+          break;
         }
       }
       if( op ){
@@ -115975,7 +118268,12 @@
   int ii;
   float overlap = 0.0;
   for(ii=0; ii<nCell; ii++){
-    if( ii!=iExclude ){
+#if VARIANT_RSTARTREE_CHOOSESUBTREE
+    if( ii!=iExclude )
+#else
+    assert( iExclude==-1 );
+#endif
+    {
       int jj;
       float o = 1.0;
       for(jj=0; jj<(pRtree->nDim*2); jj+=2){
@@ -116068,22 +118366,31 @@
     ** the smallest area.
     */
     for(iCell=0; iCell<nCell; iCell++){
+      int bBest = 0;
       float growth;
       float area;
       float overlap = 0.0;
       nodeGetCell(pRtree, pNode, iCell, &cell);
       growth = cellGrowth(pRtree, &cell, pCell);
       area = cellArea(pRtree, &cell);
+
 #if VARIANT_RSTARTREE_CHOOSESUBTREE
       if( ii==(pRtree->iDepth-1) ){
         overlap = cellOverlapEnlargement(pRtree,&cell,pCell,aCell,nCell,iCell);
       }
-#endif
       if( (iCell==0) 
        || (overlap<fMinOverlap) 
        || (overlap==fMinOverlap && growth<fMinGrowth)
        || (overlap==fMinOverlap && growth==fMinGrowth && area<fMinArea)
       ){
+        bBest = 1;
+      }
+#else
+      if( iCell==0||growth<fMinGrowth||(growth==fMinGrowth && area<fMinArea) ){
+        bBest = 1;
+      }
+#endif
+      if( bBest ){
         fMinOverlap = overlap;
         fMinGrowth = growth;
         fMinArea = area;
@@ -116106,16 +118413,20 @@
 ** the node pNode. This function updates the bounding box cells in
 ** all ancestor elements.
 */
-static void AdjustTree(
+static int AdjustTree(
   Rtree *pRtree,                    /* Rtree table */
   RtreeNode *pNode,                 /* Adjust ancestry of this node. */
   RtreeCell *pCell                  /* This cell was just inserted */
 ){
   RtreeNode *p = pNode;
   while( p->pParent ){
-    RtreeCell cell;
     RtreeNode *pParent = p->pParent;
-    int iCell = nodeParentIndex(pRtree, p);
+    RtreeCell cell;
+    int iCell;
+
+    if( nodeParentIndex(pRtree, p, &iCell) ){
+      return SQLITE_CORRUPT;
+    }
 
     nodeGetCell(pRtree, pParent, iCell, &cell);
     if( !cellContains(pRtree, &cell, pCell) ){
@@ -116125,6 +118436,7 @@
  
     p = pParent;
   }
+  return SQLITE_OK;
 }
 
 /*
@@ -116653,14 +118965,14 @@
   nCell++;
 
   if( pNode->iNode==1 ){
-    pRight = nodeNew(pRtree, pNode, 1);
-    pLeft = nodeNew(pRtree, pNode, 1);
+    pRight = nodeNew(pRtree, pNode);
+    pLeft = nodeNew(pRtree, pNode);
     pRtree->iDepth++;
     pNode->isDirty = 1;
     writeInt16(pNode->zData, pRtree->iDepth);
   }else{
     pLeft = pNode;
-    pRight = nodeNew(pRtree, pLeft->pParent, 1);
+    pRight = nodeNew(pRtree, pLeft->pParent);
     nodeReference(pLeft);
   }
 
@@ -116677,8 +118989,12 @@
     goto splitnode_out;
   }
 
-  /* Ensure both child nodes have node numbers assigned to them. */
-  if( (0==pRight->iNode && SQLITE_OK!=(rc = nodeWrite(pRtree, pRight)))
+  /* Ensure both child nodes have node numbers assigned to them by calling
+  ** nodeWrite(). Node pRight always needs a node number, as it was created
+  ** by nodeNew() above. But node pLeft sometimes already has a node number.
+  ** In this case avoid the all to nodeWrite().
+  */
+  if( SQLITE_OK!=(rc = nodeWrite(pRtree, pRight))
    || (0==pLeft->iNode && SQLITE_OK!=(rc = nodeWrite(pRtree, pLeft)))
   ){
     goto splitnode_out;
@@ -116694,9 +119010,15 @@
     }
   }else{
     RtreeNode *pParent = pLeft->pParent;
-    int iCell = nodeParentIndex(pRtree, pLeft);
-    nodeOverwriteCell(pRtree, pParent, &leftbbox, iCell);
-    AdjustTree(pRtree, pParent, &leftbbox);
+    int iCell;
+    rc = nodeParentIndex(pRtree, pLeft, &iCell);
+    if( rc==SQLITE_OK ){
+      nodeOverwriteCell(pRtree, pParent, &leftbbox, iCell);
+      rc = AdjustTree(pRtree, pParent, &leftbbox);
+    }
+    if( rc!=SQLITE_OK ){
+      goto splitnode_out;
+    }
   }
   if( (rc = rtreeInsertCell(pRtree, pRight->pParent, &rightbbox, iHeight+1)) ){
     goto splitnode_out;
@@ -116740,20 +119062,43 @@
   return rc;
 }
 
+/*
+** If node pLeaf is not the root of the r-tree and its pParent pointer is 
+** still NULL, load all ancestor nodes of pLeaf into memory and populate
+** the pLeaf->pParent chain all the way up to the root node.
+**
+** This operation is required when a row is deleted (or updated - an update
+** is implemented as a delete followed by an insert). SQLite provides the
+** rowid of the row to delete, which can be used to find the leaf on which
+** the entry resides (argument pLeaf). Once the leaf is located, this 
+** function is called to determine its ancestry.
+*/
 static int fixLeafParent(Rtree *pRtree, RtreeNode *pLeaf){
   int rc = SQLITE_OK;
-  if( pLeaf->iNode!=1 && pLeaf->pParent==0 ){
-    sqlite3_bind_int64(pRtree->pReadParent, 1, pLeaf->iNode);
-    if( sqlite3_step(pRtree->pReadParent)==SQLITE_ROW ){
-      i64 iNode = sqlite3_column_int64(pRtree->pReadParent, 0);
-      rc = nodeAcquire(pRtree, iNode, 0, &pLeaf->pParent);
-    }else{
-      rc = SQLITE_ERROR;
+  RtreeNode *pChild = pLeaf;
+  while( rc==SQLITE_OK && pChild->iNode!=1 && pChild->pParent==0 ){
+    int rc2 = SQLITE_OK;          /* sqlite3_reset() return code */
+    sqlite3_bind_int64(pRtree->pReadParent, 1, pChild->iNode);
+    rc = sqlite3_step(pRtree->pReadParent);
+    if( rc==SQLITE_ROW ){
+      RtreeNode *pTest;           /* Used to test for reference loops */
+      i64 iNode;                  /* Node number of parent node */
+
+      /* Before setting pChild->pParent, test that we are not creating a
+      ** loop of references (as we would if, say, pChild==pParent). We don't
+      ** want to do this as it leads to a memory leak when trying to delete
+      ** the referenced counted node structures.
+      */
+      iNode = sqlite3_column_int64(pRtree->pReadParent, 0);
+      for(pTest=pLeaf; pTest && pTest->iNode!=iNode; pTest=pTest->pParent);
+      if( !pTest ){
+        rc2 = nodeAcquire(pRtree, iNode, 0, &pChild->pParent);
+      }
     }
-    sqlite3_reset(pRtree->pReadParent);
-    if( rc==SQLITE_OK ){
-      rc = fixLeafParent(pRtree, pLeaf->pParent);
-    }
+    rc = sqlite3_reset(pRtree->pReadParent);
+    if( rc==SQLITE_OK ) rc = rc2;
+    if( rc==SQLITE_OK && !pChild->pParent ) rc = SQLITE_CORRUPT;
+    pChild = pChild->pParent;
   }
   return rc;
 }
@@ -116762,18 +119107,24 @@
 
 static int removeNode(Rtree *pRtree, RtreeNode *pNode, int iHeight){
   int rc;
+  int rc2;
   RtreeNode *pParent;
   int iCell;
 
   assert( pNode->nRef==1 );
 
   /* Remove the entry in the parent cell. */
-  iCell = nodeParentIndex(pRtree, pNode);
-  pParent = pNode->pParent;
-  pNode->pParent = 0;
-  if( SQLITE_OK!=(rc = deleteCell(pRtree, pParent, iCell, iHeight+1)) 
-   || SQLITE_OK!=(rc = nodeRelease(pRtree, pParent))
-  ){
+  rc = nodeParentIndex(pRtree, pNode, &iCell);
+  if( rc==SQLITE_OK ){
+    pParent = pNode->pParent;
+    pNode->pParent = 0;
+    rc = deleteCell(pRtree, pParent, iCell, iHeight+1);
+  }
+  rc2 = nodeRelease(pRtree, pParent);
+  if( rc==SQLITE_OK ){
+    rc = rc2;
+  }
+  if( rc!=SQLITE_OK ){
     return rc;
   }
 
@@ -116803,8 +119154,9 @@
   return SQLITE_OK;
 }
 
-static void fixBoundingBox(Rtree *pRtree, RtreeNode *pNode){
+static int fixBoundingBox(Rtree *pRtree, RtreeNode *pNode){
   RtreeNode *pParent = pNode->pParent;
+  int rc = SQLITE_OK; 
   if( pParent ){
     int ii; 
     int nCell = NCELL(pNode);
@@ -116816,10 +119168,13 @@
       cellUnion(pRtree, &box, &cell);
     }
     box.iRowid = pNode->iNode;
-    ii = nodeParentIndex(pRtree, pNode);
-    nodeOverwriteCell(pRtree, pParent, &box, ii);
-    fixBoundingBox(pRtree, pParent);
+    rc = nodeParentIndex(pRtree, pNode, &ii);
+    if( rc==SQLITE_OK ){
+      nodeOverwriteCell(pRtree, pParent, &box, ii);
+      rc = fixBoundingBox(pRtree, pParent);
+    }
   }
+  return rc;
 }
 
 /*
@@ -116827,6 +119182,7 @@
 ** cell, adjust the r-tree data structure if required.
 */
 static int deleteCell(Rtree *pRtree, RtreeNode *pNode, int iCell, int iHeight){
+  RtreeNode *pParent;
   int rc;
 
   if( SQLITE_OK!=(rc = fixLeafParent(pRtree, pNode)) ){
@@ -116843,14 +119199,13 @@
   ** cell in the parent node so that it tightly contains the updated
   ** node.
   */
-  if( pNode->iNode!=1 ){
-    RtreeNode *pParent = pNode->pParent;
-    if( (pParent->iNode!=1 || NCELL(pParent)!=1) 
-     && (NCELL(pNode)<RTREE_MINCELLS(pRtree))
-    ){
+  pParent = pNode->pParent;
+  assert( pParent || pNode->iNode==1 );
+  if( pParent ){
+    if( NCELL(pNode)<RTREE_MINCELLS(pRtree) ){
       rc = removeNode(pRtree, pNode, iHeight);
     }else{
-      fixBoundingBox(pRtree, pNode);
+      rc = fixBoundingBox(pRtree, pNode);
     }
   }
 
@@ -116933,7 +119288,7 @@
     }
   }
   if( rc==SQLITE_OK ){
-    fixBoundingBox(pRtree, pNode);
+    rc = fixBoundingBox(pRtree, pNode);
   }
   for(; rc==SQLITE_OK && ii<nCell; ii++){
     /* Find a node to store this cell in. pNode->iNode currently contains
@@ -116987,11 +119342,13 @@
     rc = SplitNode(pRtree, pNode, pCell, iHeight);
 #endif
   }else{
-    AdjustTree(pRtree, pNode, pCell);
-    if( iHeight==0 ){
-      rc = rowidWrite(pRtree, pCell->iRowid, pNode->iNode);
-    }else{
-      rc = parentWrite(pRtree, pCell->iRowid, pNode->iNode);
+    rc = AdjustTree(pRtree, pNode, pCell);
+    if( rc==SQLITE_OK ){
+      if( iHeight==0 ){
+        rc = rowidWrite(pRtree, pCell->iRowid, pNode->iNode);
+      }else{
+        rc = parentWrite(pRtree, pCell->iRowid, pNode->iNode);
+      }
     }
   }
   return rc;
@@ -117061,7 +119418,6 @@
   rtreeReference(pRtree);
 
   assert(nData>=1);
-  assert(hashIsEmpty(pRtree));
 
   /* If azData[0] is not an SQL NULL value, it is the rowid of a
   ** record to delete from the r-tree table. The following block does
@@ -117087,8 +119443,10 @@
     /* Delete the cell in question from the leaf node. */
     if( rc==SQLITE_OK ){
       int rc2;
-      iCell = nodeRowidIndex(pRtree, pLeaf, iDelete);
-      rc = deleteCell(pRtree, pLeaf, iCell, 0);
+      rc = nodeRowidIndex(pRtree, pLeaf, iDelete, &iCell);
+      if( rc==SQLITE_OK ){
+        rc = deleteCell(pRtree, pLeaf, iCell, 0);
+      }
       rc2 = nodeRelease(pRtree, pLeaf);
       if( rc==SQLITE_OK ){
         rc = rc2;
@@ -117110,19 +119468,20 @@
     ** the root node (the operation that Gutman's paper says to perform 
     ** in this scenario).
     */
-    if( rc==SQLITE_OK && pRtree->iDepth>0 ){
-      if( rc==SQLITE_OK && NCELL(pRoot)==1 ){
-        RtreeNode *pChild;
-        i64 iChild = nodeGetRowid(pRtree, pRoot, 0);
-        rc = nodeAcquire(pRtree, iChild, pRoot, &pChild);
-        if( rc==SQLITE_OK ){
-          rc = removeNode(pRtree, pChild, pRtree->iDepth-1);
-        }
-        if( rc==SQLITE_OK ){
-          pRtree->iDepth--;
-          writeInt16(pRoot->zData, pRtree->iDepth);
-          pRoot->isDirty = 1;
-        }
+    if( rc==SQLITE_OK && pRtree->iDepth>0 && NCELL(pRoot)==1 ){
+      int rc2;
+      RtreeNode *pChild;
+      i64 iChild = nodeGetRowid(pRtree, pRoot, 0);
+      rc = nodeAcquire(pRtree, iChild, pRoot, &pChild);
+      if( rc==SQLITE_OK ){
+        rc = removeNode(pRtree, pChild, pRtree->iDepth-1);
+      }
+      rc2 = nodeRelease(pRtree, pChild);
+      if( rc==SQLITE_OK ) rc = rc2;
+      if( rc==SQLITE_OK ){
+        pRtree->iDepth--;
+        writeInt16(pRoot->zData, pRtree->iDepth);
+        pRoot->isDirty = 1;
       }
     }
 
@@ -117412,7 +119771,7 @@
   Rtree *pRtree;
   int nDb;              /* Length of string argv[1] */
   int nName;            /* Length of string argv[2] */
-  int eCoordType = (int)pAux;
+  int eCoordType = (pAux ? RTREE_COORD_INT32 : RTREE_COORD_REAL32);
 
   const char *aErrMsg[] = {
     0,                                                    /* 0 */
@@ -117558,12 +119917,10 @@
 ** function "rtreenode".
 */
 SQLITE_PRIVATE int sqlite3RtreeInit(sqlite3 *db){
-  int rc = SQLITE_OK;
+  const int utf8 = SQLITE_UTF8;
+  int rc;
 
-  if( rc==SQLITE_OK ){
-    int utf8 = SQLITE_UTF8;
-    rc = sqlite3_create_function(db, "rtreenode", 2, utf8, 0, rtreenode, 0, 0);
-  }
+  rc = sqlite3_create_function(db, "rtreenode", 2, utf8, 0, rtreenode, 0, 0);
   if( rc==SQLITE_OK ){
     int utf8 = SQLITE_UTF8;
     rc = sqlite3_create_function(db, "rtreedepth", 1, utf8, 0,rtreedepth, 0, 0);
@@ -117580,6 +119937,70 @@
   return rc;
 }
 
+/*
+** A version of sqlite3_free() that can be used as a callback. This is used
+** in two places - as the destructor for the blob value returned by the
+** invocation of a geometry function, and as the destructor for the geometry
+** functions themselves.
+*/
+static void doSqlite3Free(void *p){
+  sqlite3_free(p);
+}
+
+/*
+** Each call to sqlite3_rtree_geometry_callback() creates an ordinary SQLite
+** scalar user function. This C function is the callback used for all such
+** registered SQL functions.
+**
+** The scalar user functions return a blob that is interpreted by r-tree
+** table MATCH operators.
+*/
+static void geomCallback(sqlite3_context *ctx, int nArg, sqlite3_value **aArg){
+  RtreeGeomCallback *pGeomCtx = (RtreeGeomCallback *)sqlite3_user_data(ctx);
+  RtreeMatchArg *pBlob;
+  int nBlob;
+
+  nBlob = sizeof(RtreeMatchArg) + (nArg-1)*sizeof(double);
+  pBlob = (RtreeMatchArg *)sqlite3_malloc(nBlob);
+  if( !pBlob ){
+    sqlite3_result_error_nomem(ctx);
+  }else{
+    int i;
+    pBlob->magic = RTREE_GEOMETRY_MAGIC;
+    pBlob->xGeom = pGeomCtx->xGeom;
+    pBlob->pContext = pGeomCtx->pContext;
+    pBlob->nParam = nArg;
+    for(i=0; i<nArg; i++){
+      pBlob->aParam[i] = sqlite3_value_double(aArg[i]);
+    }
+    sqlite3_result_blob(ctx, pBlob, nBlob, doSqlite3Free);
+  }
+}
+
+/*
+** Register a new geometry function for use with the r-tree MATCH operator.
+*/
+SQLITE_API int sqlite3_rtree_geometry_callback(
+  sqlite3 *db,
+  const char *zGeom,
+  int (*xGeom)(sqlite3_rtree_geometry *, int, double *, int *),
+  void *pContext
+){
+  RtreeGeomCallback *pGeomCtx;      /* Context object for new user-function */
+
+  /* Allocate and populate the context object. */
+  pGeomCtx = (RtreeGeomCallback *)sqlite3_malloc(sizeof(RtreeGeomCallback));
+  if( !pGeomCtx ) return SQLITE_NOMEM;
+  pGeomCtx->xGeom = xGeom;
+  pGeomCtx->pContext = pContext;
+
+  /* Create the new user-function. Register a destructor function to delete
+  ** the context object when it is no longer required.  */
+  return sqlite3_create_function_v2(db, zGeom, -1, SQLITE_ANY, 
+      (void *)pGeomCtx, geomCallback, 0, 0, doSqlite3Free
+  );
+}
+
 #if !SQLITE_CORE
 SQLITE_API int sqlite3_extension_init(
   sqlite3 *db,
diff --git a/dist/sqlite3.c.orig b/dist/sqlite3.c.orig
index 2ac17c8..b15a389 100644
--- a/dist/sqlite3.c.orig
+++ b/dist/sqlite3.c.orig
@@ -1,6 +1,6 @@
 /******************************************************************************
 ** This file is an amalgamation of many separate C source files from SQLite
-** version 3.7.0.  By combining all the individual C code files into this 
+** version 3.7.3.  By combining all the individual C code files into this 
 ** single large file, the entire code can be compiled as a one translation
 ** unit.  This allows many compilers to do optimizations that would not be
 ** possible if the files were compiled separately.  Performance improvements
@@ -215,20 +215,21 @@
 # define SQLITE_MAX_VARIABLE_NUMBER 999
 #endif
 
-/* Maximum page size.  The upper bound on this value is 32768.  This a limit
-** imposed by the necessity of storing the value in a 2-byte unsigned integer
-** and the fact that the page size must be a power of 2.
+/* Maximum page size.  The upper bound on this value is 65536.  This a limit
+** imposed by the use of 16-bit offsets within each page.
 **
-** If this limit is changed, then the compiled library is technically
-** incompatible with an SQLite library compiled with a different limit. If
-** a process operating on a database with a page-size of 65536 bytes 
-** crashes, then an instance of SQLite compiled with the default page-size 
-** limit will not be able to rollback the aborted transaction. This could
-** lead to database corruption.
+** Earlier versions of SQLite allowed the user to change this value at
+** compile time. This is no longer permitted, on the grounds that it creates
+** a library that is technically incompatible with an SQLite library 
+** compiled with a different limit. If a process operating on a database 
+** with a page-size of 65536 bytes crashes, then an instance of SQLite 
+** compiled with the default page-size limit will not be able to rollback 
+** the aborted transaction. This could lead to database corruption.
 */
-#ifndef SQLITE_MAX_PAGE_SIZE
-# define SQLITE_MAX_PAGE_SIZE 32768
+#ifdef SQLITE_MAX_PAGE_SIZE
+# undef SQLITE_MAX_PAGE_SIZE
 #endif
+#define SQLITE_MAX_PAGE_SIZE 65536
 
 
 /*
@@ -353,15 +354,21 @@
 #endif
 
 /*
-** The SQLITE_THREADSAFE macro must be defined as either 0 or 1.
+** The SQLITE_THREADSAFE macro must be defined as 0, 1, or 2.
+** 0 means mutexes are permanently disable and the library is never
+** threadsafe.  1 means the library is serialized which is the highest
+** level of threadsafety.  2 means the libary is multithreaded - multiple
+** threads can use SQLite as long as no two threads try to use the same
+** database connection at the same time.
+**
 ** Older versions of SQLite used an optional THREADSAFE macro.
-** We support that for legacy
+** We support that for legacy.
 */
 #if !defined(SQLITE_THREADSAFE)
 #if defined(THREADSAFE)
 # define SQLITE_THREADSAFE THREADSAFE
 #else
-# define SQLITE_THREADSAFE 1
+# define SQLITE_THREADSAFE 1 /* IMP: R-07272-22309 */
 #endif
 #endif
 
@@ -516,7 +523,7 @@
 ** to fit in 32-bits.  This macro is used inside of various testcase()
 ** macros to verify that we have tested SQLite for large-file support.
 */
-#define IS_BIG_INT(X)  (((X)&(i64)0xffffffff)!=0)
+#define IS_BIG_INT(X)  (((X)&~(i64)0xffffffff)!=0)
 
 /*
 ** The macro unlikely() is a hint that surrounds a boolean
@@ -633,7 +640,7 @@
 **
 ** Since version 3.6.18, SQLite source code has been stored in the
 ** <a href="http://www.fossil-scm.org/">Fossil configuration management
-** system</a>.  ^The SQLITE_SOURCE_ID macro evalutes to
+** system</a>.  ^The SQLITE_SOURCE_ID macro evaluates to
 ** a string which identifies a particular check-in of SQLite
 ** within its configuration management system.  ^The SQLITE_SOURCE_ID
 ** string contains the date and time of the check-in (UTC) and an SHA1
@@ -643,9 +650,9 @@
 ** [sqlite3_libversion_number()], [sqlite3_sourceid()],
 ** [sqlite_version()] and [sqlite_source_id()].
 */
-#define SQLITE_VERSION        "3.7.0"
-#define SQLITE_VERSION_NUMBER 3007000
-#define SQLITE_SOURCE_ID      "2010-07-07 14:45:41 8eefc287265443ec043bdab629597e79c9d22006"
+#define SQLITE_VERSION        "3.7.3"
+#define SQLITE_VERSION_NUMBER 3007003
+#define SQLITE_SOURCE_ID      "2010-09-28 07:24:50 88108fff672b6012ffe87ba4b1efe6d5a07037d1"
 
 /*
 ** CAPI3REF: Run-Time Library Version Numbers
@@ -690,7 +697,7 @@
 ** compile time.  ^The SQLITE_ prefix may be omitted from the 
 ** option name passed to sqlite3_compileoption_used().  
 **
-** ^The sqlite3_compileoption_get() function allows interating
+** ^The sqlite3_compileoption_get() function allows iterating
 ** over the list of options that were defined at compile time by
 ** returning the N-th compile time option string.  ^If N is out of range,
 ** sqlite3_compileoption_get() returns a NULL pointer.  ^The SQLITE_ 
@@ -698,7 +705,7 @@
 ** sqlite3_compileoption_get().
 **
 ** ^Support for the diagnostic functions sqlite3_compileoption_used()
-** and sqlite3_compileoption_get() may be omitted by specifing the 
+** and sqlite3_compileoption_get() may be omitted by specifying the 
 ** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
 **
 ** See also: SQL functions [sqlite_compileoption_used()] and
@@ -804,7 +811,7 @@
 **
 ** ^The sqlite3_close() routine is the destructor for the [sqlite3] object.
 ** ^Calls to sqlite3_close() return SQLITE_OK if the [sqlite3] object is
-** successfullly destroyed and all associated resources are deallocated.
+** successfully destroyed and all associated resources are deallocated.
 **
 ** Applications must [sqlite3_finalize | finalize] all [prepared statements]
 ** and [sqlite3_blob_close | close] all [BLOB handles] associated with
@@ -1017,11 +1024,12 @@
 #define SQLITE_OPEN_FULLMUTEX        0x00010000  /* Ok for sqlite3_open_v2() */
 #define SQLITE_OPEN_SHAREDCACHE      0x00020000  /* Ok for sqlite3_open_v2() */
 #define SQLITE_OPEN_PRIVATECACHE     0x00040000  /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_WAL              0x00080000  /* VFS only */
 
 /*
 ** CAPI3REF: Device Characteristics
 **
-** The xDeviceCapabilities method of the [sqlite3_io_methods]
+** The xDeviceCharacteristics method of the [sqlite3_io_methods]
 ** object returns an integer which is a vector of the these
 ** bit values expressing I/O characteristics of the mass storage
 ** device that holds the file that the [sqlite3_io_methods]
@@ -1201,11 +1209,10 @@
   int (*xSectorSize)(sqlite3_file*);
   int (*xDeviceCharacteristics)(sqlite3_file*);
   /* Methods above are valid for version 1 */
-  int (*xShmOpen)(sqlite3_file*);
+  int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
   int (*xShmLock)(sqlite3_file*, int offset, int n, int flags);
-  int (*xShmMap)(sqlite3_file*, int iPage, int pgsz, int, void volatile**);
   void (*xShmBarrier)(sqlite3_file*);
-  int (*xShmClose)(sqlite3_file*, int deleteFlag);
+  int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
   /* Methods above are valid for version 2 */
   /* Additional methods may be added in future releases */
 };
@@ -1231,12 +1238,21 @@
 ** is often close.  The underlying VFS might choose to preallocate database
 ** file space based on this hint in order to help writes to the database
 ** file run faster.
+**
+** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
+** extends and truncates the database file in chunks of a size specified
+** by the user. The fourth argument to [sqlite3_file_control()] should 
+** point to an integer (type int) containing the new chunk-size to use
+** for the nominated database. Allocating database file space in large
+** chunks (say 1MB at a time), may reduce file-system fragmentation and
+** improve performance on some systems.
 */
 #define SQLITE_FCNTL_LOCKSTATE        1
 #define SQLITE_GET_LOCKPROXYFILE      2
 #define SQLITE_SET_LOCKPROXYFILE      3
 #define SQLITE_LAST_ERRNO             4
 #define SQLITE_FCNTL_SIZE_HINT        5
+#define SQLITE_FCNTL_CHUNK_SIZE       6
 
 /*
 ** CAPI3REF: Mutex Handle
@@ -1284,15 +1300,19 @@
 ** The zName field holds the name of the VFS module.  The name must
 ** be unique across all VFS modules.
 **
-** SQLite will guarantee that the zFilename parameter to xOpen
+** ^SQLite guarantees that the zFilename parameter to xOpen
 ** is either a NULL pointer or string obtained
-** from xFullPathname().  SQLite further guarantees that
+** from xFullPathname() with an optional suffix added.
+** ^If a suffix is added to the zFilename parameter, it will
+** consist of a single "-" character followed by no more than
+** 10 alphanumeric and/or "-" characters.
+** ^SQLite further guarantees that
 ** the string will be valid and unchanged until xClose() is
 ** called. Because of the previous sentence,
 ** the [sqlite3_file] can safely store a pointer to the
 ** filename if it needs to remember the filename for some reason.
-** If the zFilename parameter is xOpen is a NULL pointer then xOpen
-** must invent its own temporary name for the file.  Whenever the 
+** If the zFilename parameter to xOpen is a NULL pointer then xOpen
+** must invent its own temporary name for the file.  ^Whenever the 
 ** xFilename parameter is NULL it will also be the case that the
 ** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
 **
@@ -1303,7 +1323,7 @@
 ** If xOpen() opens a file read-only then it sets *pOutFlags to
 ** include [SQLITE_OPEN_READONLY].  Other bits in *pOutFlags may be set.
 **
-** SQLite will also add one of the following flags to the xOpen()
+** ^(SQLite will also add one of the following flags to the xOpen()
 ** call, depending on the object being opened:
 **
 ** <ul>
@@ -1314,7 +1334,8 @@
 ** <li>  [SQLITE_OPEN_TRANSIENT_DB]
 ** <li>  [SQLITE_OPEN_SUBJOURNAL]
 ** <li>  [SQLITE_OPEN_MASTER_JOURNAL]
-** </ul>
+** <li>  [SQLITE_OPEN_WAL]
+** </ul>)^
 **
 ** The file I/O implementation can use the object type flags to
 ** change the way it deals with files.  For example, an application
@@ -1333,10 +1354,11 @@
 ** </ul>
 **
 ** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
-** deleted when it is closed.  The [SQLITE_OPEN_DELETEONCLOSE]
-** will be set for TEMP  databases, journals and for subjournals.
+** deleted when it is closed.  ^The [SQLITE_OPEN_DELETEONCLOSE]
+** will be set for TEMP databases and their journals, transient
+** databases, and subjournals.
 **
-** The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
+** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
 ** with the [SQLITE_OPEN_CREATE] flag, which are both directly
 ** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
 ** API.  The SQLITE_OPEN_EXCLUSIVE flag, when paired with the 
@@ -1345,7 +1367,7 @@
 ** It is <i>not</i> used to indicate the file should be opened 
 ** for exclusive access.
 **
-** At least szOsFile bytes of memory are allocated by SQLite
+** ^At least szOsFile bytes of memory are allocated by SQLite
 ** to hold the  [sqlite3_file] structure passed as the third
 ** argument to xOpen.  The xOpen method does not have to
 ** allocate the structure; it should just fill it in.  Note that
@@ -1355,13 +1377,13 @@
 ** element will be valid after xOpen returns regardless of the success
 ** or failure of the xOpen call.
 **
-** The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
+** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
 ** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
 ** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
 ** to test whether a file is at least readable.   The file can be a
 ** directory.
 **
-** SQLite will always allocate at least mxPathname+1 bytes for the
+** ^SQLite will always allocate at least mxPathname+1 bytes for the
 ** output buffer xFullPathname.  The exact size of the output buffer
 ** is also passed as a parameter to both  methods. If the output buffer
 ** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
@@ -1375,10 +1397,10 @@
 ** of good-quality randomness into zOut.  The return value is
 ** the actual number of bytes of randomness obtained.
 ** The xSleep() method causes the calling thread to sleep for at
-** least the number of microseconds given.  The xCurrentTime()
+** least the number of microseconds given.  ^The xCurrentTime()
 ** method returns a Julian Day Number for the current date and time as
 ** a floating point value.
-** The xCurrentTimeInt64() method returns, as an integer, the Julian
+** ^The xCurrentTimeInt64() method returns, as an integer, the Julian
 ** Day Number multipled by 86400000 (the number of milliseconds in 
 ** a 24-hour day).  
 ** ^SQLite will use the xCurrentTimeInt64() method to get the current
@@ -1428,13 +1450,20 @@
 ** With SQLITE_ACCESS_EXISTS, the xAccess method
 ** simply checks whether the file exists.
 ** With SQLITE_ACCESS_READWRITE, the xAccess method
-** checks whether the file is both readable and writable.
+** checks whether the named directory is both readable and writable
+** (in other words, if files can be added, removed, and renamed within
+** the directory).
+** The SQLITE_ACCESS_READWRITE constant is currently used only by the
+** [temp_store_directory pragma], though this could change in a future
+** release of SQLite.
 ** With SQLITE_ACCESS_READ, the xAccess method
-** checks whether the file is readable.
+** checks whether the file is readable.  The SQLITE_ACCESS_READ constant is
+** currently unused, though it might be used in a future release of
+** SQLite.
 */
 #define SQLITE_ACCESS_EXISTS    0
-#define SQLITE_ACCESS_READWRITE 1
-#define SQLITE_ACCESS_READ      2
+#define SQLITE_ACCESS_READWRITE 1   /* Used by PRAGMA temp_store_directory */
+#define SQLITE_ACCESS_READ      2   /* Unused */
 
 /*
 ** CAPI3REF: Flags for the xShmLock VFS method
@@ -1768,7 +1797,7 @@
 **   <ul>
 **   <li> [sqlite3_memory_used()]
 **   <li> [sqlite3_memory_highwater()]
-**   <li> [sqlite3_soft_heap_limit()]
+**   <li> [sqlite3_soft_heap_limit64()]
 **   <li> [sqlite3_status()]
 **   </ul>)^
 ** ^Memory allocation statistics are enabled by default unless SQLite is
@@ -1782,15 +1811,14 @@
 ** aligned memory buffer from which the scrach allocations will be
 ** drawn, the size of each scratch allocation (sz),
 ** and the maximum number of scratch allocations (N).  The sz
-** argument must be a multiple of 16. The sz parameter should be a few bytes
-** larger than the actual scratch space required due to internal overhead.
+** argument must be a multiple of 16.
 ** The first argument must be a pointer to an 8-byte aligned buffer
 ** of at least sz*N bytes of memory.
-** ^SQLite will use no more than one scratch buffer per thread.  So
-** N should be set to the expected maximum number of threads.  ^SQLite will
-** never require a scratch buffer that is more than 6 times the database
-** page size. ^If SQLite needs needs additional scratch memory beyond 
-** what is provided by this configuration option, then 
+** ^SQLite will use no more than two scratch buffers per thread.  So
+** N should be set to twice the expected maximum number of threads.
+** ^SQLite will never require a scratch buffer that is more than 6
+** times the database page size. ^If SQLite needs needs additional
+** scratch memory beyond what is provided by this configuration option, then 
 ** [sqlite3_malloc()] will be used to obtain the memory needed.</dd>
 **
 ** <dt>SQLITE_CONFIG_PAGECACHE</dt>
@@ -1810,8 +1838,7 @@
 ** memory needs for the first N pages that it adds to cache.  ^If additional
 ** page cache memory is needed beyond what is provided by this option, then
 ** SQLite goes to [sqlite3_malloc()] for the additional storage space.
-** ^The implementation might use one or more of the N buffers to hold 
-** memory accounting information. The pointer in the first argument must
+** The pointer in the first argument must
 ** be aligned to an 8-byte boundary or subsequent behavior of SQLite
 ** will be undefined.</dd>
 **
@@ -1940,8 +1967,14 @@
 ** or equal to the product of the second and third arguments.  The buffer
 ** must be aligned to an 8-byte boundary.  ^If the second argument to
 ** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally
-** rounded down to the next smaller
-** multiple of 8.  See also: [SQLITE_CONFIG_LOOKASIDE]</dd>
+** rounded down to the next smaller multiple of 8.  ^(The lookaside memory
+** configuration for a database connection can only be changed when that
+** connection is not currently using lookaside memory, or in other words
+** when the "current value" returned by
+** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero.
+** Any attempt to change the lookaside memory configuration when lookaside
+** memory is in use leaves the configuration unchanged and returns 
+** [SQLITE_BUSY].)^</dd>
 **
 ** </dl>
 */
@@ -2462,7 +2495,9 @@
 ** is not freed.
 **
 ** ^The memory returned by sqlite3_malloc() and sqlite3_realloc()
-** is always aligned to at least an 8 byte boundary.
+** is always aligned to at least an 8 byte boundary, or to a
+** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time
+** option is used.
 **
 ** In SQLite version 3.5.0 and 3.5.1, it was possible to define
 ** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
@@ -2705,7 +2740,13 @@
 ** ^The callback function registered by sqlite3_profile() is invoked
 ** as each SQL statement finishes.  ^The profile callback contains
 ** the original statement text and an estimate of wall-clock time
-** of how long that statement took to run.
+** of how long that statement took to run.  ^The profile callback
+** time is in units of nanoseconds, however the current implementation
+** is only capable of millisecond resolution so the six least significant
+** digits in the time are meaningless.  Future versions of SQLite
+** might provide greater resolution on the profiler callback.  The
+** sqlite3_profile() function is considered experimental and is
+** subject to change in future versions of SQLite.
 */
 SQLITE_API void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
 SQLITE_API SQLITE_EXPERIMENTAL void *sqlite3_profile(sqlite3*,
@@ -2714,17 +2755,28 @@
 /*
 ** CAPI3REF: Query Progress Callbacks
 **
-** ^This routine configures a callback function - the
-** progress callback - that is invoked periodically during long
-** running calls to [sqlite3_exec()], [sqlite3_step()] and
-** [sqlite3_get_table()].  An example use for this
+** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback
+** function X to be invoked periodically during long running calls to
+** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for
+** database connection D.  An example use for this
 ** interface is to keep a GUI updated during a large query.
 **
+** ^The parameter P is passed through as the only parameter to the 
+** callback function X.  ^The parameter N is the number of 
+** [virtual machine instructions] that are evaluated between successive
+** invocations of the callback X.
+**
+** ^Only a single progress handler may be defined at one time per
+** [database connection]; setting a new progress handler cancels the
+** old one.  ^Setting parameter X to NULL disables the progress handler.
+** ^The progress handler is also disabled by setting N to a value less
+** than 1.
+**
 ** ^If the progress callback returns non-zero, the operation is
 ** interrupted.  This feature can be used to implement a
 ** "Cancel" button on a GUI progress dialog box.
 **
-** The progress handler must not do anything that will modify
+** The progress handler callback must not do anything that will modify
 ** the database connection that invoked the progress handler.
 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
 ** database connections for the meaning of "modify" in this paragraph.
@@ -2783,7 +2835,7 @@
 ** If the 3rd parameter to sqlite3_open_v2() is not one of the
 ** combinations shown above or one of the combinations shown above combined
 ** with the [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX],
-** [SQLITE_OPEN_SHAREDCACHE] and/or [SQLITE_OPEN_SHAREDCACHE] flags,
+** [SQLITE_OPEN_SHAREDCACHE] and/or [SQLITE_OPEN_PRIVATECACHE] flags,
 ** then the behavior is undefined.
 **
 ** ^If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection
@@ -2908,17 +2960,22 @@
 ** [database connection] whose limit is to be set or queried.  The
 ** second parameter is one of the [limit categories] that define a
 ** class of constructs to be size limited.  The third parameter is the
-** new limit for that construct.  The function returns the old limit.)^
+** new limit for that construct.)^
 **
 ** ^If the new limit is a negative number, the limit is unchanged.
-** ^(For the limit category of SQLITE_LIMIT_XYZ there is a 
+** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a 
 ** [limits | hard upper bound]
-** set by a compile-time C preprocessor macro named 
-** [limits | SQLITE_MAX_XYZ].
+** set at compile-time by a C preprocessor macro called
+** [limits | SQLITE_MAX_<i>NAME</i>].
 ** (The "_LIMIT_" in the name is changed to "_MAX_".))^
 ** ^Attempts to increase a limit above its hard upper bound are
 ** silently truncated to the hard upper bound.
 **
+** ^Regardless of whether or not the limit was changed, the 
+** [sqlite3_limit()] interface returns the prior value of the limit.
+** ^Hence, to find the current value of a limit without changing it,
+** simply invoke this interface with the third parameter set to -1.
+**
 ** Run-time limits are intended for use in applications that manage
 ** both their own internal database and also databases that are controlled
 ** by untrusted external sources.  An example application might be a
@@ -2947,7 +3004,7 @@
 **
 ** <dl>
 ** ^(<dt>SQLITE_LIMIT_LENGTH</dt>
-** <dd>The maximum size of any string or BLOB or table row.<dd>)^
+** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^
 **
 ** ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt>
 ** <dd>The maximum length of an SQL statement, in bytes.</dd>)^
@@ -2965,7 +3022,9 @@
 **
 ** ^(<dt>SQLITE_LIMIT_VDBE_OP</dt>
 ** <dd>The maximum number of instructions in a virtual machine program
-** used to implement an SQL statement.</dd>)^
+** used to implement an SQL statement.  This limit is not currently
+** enforced, though that might be added in some future release of
+** SQLite.</dd>)^
 **
 ** ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
 ** <dd>The maximum number of arguments on a function.</dd>)^
@@ -2978,8 +3037,7 @@
 ** [GLOB] operators.</dd>)^
 **
 ** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
-** <dd>The maximum number of variables in an SQL statement that can
-** be bound.</dd>)^
+** <dd>The maximum index number of any [parameter] in an SQL statement.)^
 **
 ** ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
 ** <dd>The maximum depth of recursion for triggers.</dd>)^
@@ -3051,12 +3109,7 @@
 ** <li>
 ** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
 ** always used to do, [sqlite3_step()] will automatically recompile the SQL
-** statement and try to run it again.  ^If the schema has changed in
-** a way that makes the statement no longer valid, [sqlite3_step()] will still
-** return [SQLITE_SCHEMA].  But unlike the legacy behavior, [SQLITE_SCHEMA] is
-** now a fatal error.  Calling [sqlite3_prepare_v2()] again will not make the
-** error go away.  Note: use [sqlite3_errmsg()] to find the text
-** of the parsing error that results in an [SQLITE_SCHEMA] return.
+** statement and try to run it again.
 ** </li>
 **
 ** <li>
@@ -3069,11 +3122,16 @@
 ** </li>
 **
 ** <li>
-** ^If the value of a [parameter | host parameter] in the WHERE clause might
-** change the query plan for a statement, then the statement may be
-** automatically recompiled (as if there had been a schema change) on the first 
-** [sqlite3_step()] call following any change to the 
-** [sqlite3_bind_text | bindings] of the [parameter]. 
+** ^If the specific value bound to [parameter | host parameter] in the 
+** WHERE clause might influence the choice of query plan for a statement,
+** then the statement will be automatically recompiled, as if there had been 
+** a schema change, on the first  [sqlite3_step()] call following any change
+** to the [sqlite3_bind_text | bindings] of that [parameter]. 
+** ^The specific value of WHERE-clause [parameter] might influence the 
+** choice of query plan if the parameter is the left-hand side of a [LIKE]
+** or [GLOB] operator or if the parameter is compared to an indexed column
+** and the [SQLITE_ENABLE_STAT2] compile-time option is enabled.
+** the 
 ** </li>
 ** </ol>
 */
@@ -3140,7 +3198,7 @@
 ** then there is no distinction between protected and unprotected
 ** sqlite3_value objects and they can be used interchangeably.  However,
 ** for maximum code portability it is recommended that applications
-** still make the distinction between between protected and unprotected
+** still make the distinction between protected and unprotected
 ** sqlite3_value objects even when not strictly required.
 **
 ** ^The sqlite3_value objects that are passed as parameters into the
@@ -3186,7 +3244,7 @@
 ** </ul>
 **
 ** In the templates above, NNN represents an integer literal,
-** and VVV represents an alphanumeric identifer.)^  ^The values of these
+** and VVV represents an alphanumeric identifier.)^  ^The values of these
 ** parameters (also called "host parameter names" or "SQL parameters")
 ** can be set using the sqlite3_bind_*() routines defined here.
 **
@@ -3335,6 +3393,8 @@
 ** ^Return the number of columns in the result set returned by the
 ** [prepared statement]. ^This routine returns 0 if pStmt is an SQL
 ** statement that does not return data (for example an [UPDATE]).
+**
+** See also: [sqlite3_data_count()]
 */
 SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);
 
@@ -3525,8 +3585,14 @@
 /*
 ** CAPI3REF: Number of columns in a result set
 **
-** ^The sqlite3_data_count(P) the number of columns in the
-** of the result set of [prepared statement] P.
+** ^The sqlite3_data_count(P) interface returns the number of columns in the
+** current row of the result set of [prepared statement] P.
+** ^If prepared statement P does not have results ready to return
+** (via calls to the [sqlite3_column_int | sqlite3_column_*()] of
+** interfaces) then sqlite3_data_count(P) returns 0.
+** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.
+**
+** See also: [sqlite3_column_count()]
 */
 SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
 
@@ -3606,18 +3672,26 @@
 ** ^If the result is a numeric value then sqlite3_column_bytes() uses
 ** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
 ** the number of bytes in that string.
-** ^The value returned does not include the zero terminator at the end
-** of the string.  ^For clarity: the value returned is the number of
+** ^If the result is NULL, then sqlite3_column_bytes() returns zero.
+**
+** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16()
+** routine returns the number of bytes in that BLOB or string.
+** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts
+** the string to UTF-16 and then returns the number of bytes.
+** ^If the result is a numeric value then sqlite3_column_bytes16() uses
+** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns
+** the number of bytes in that string.
+** ^If the result is NULL, then sqlite3_column_bytes16() returns zero.
+**
+** ^The values returned by [sqlite3_column_bytes()] and 
+** [sqlite3_column_bytes16()] do not include the zero terminators at the end
+** of the string.  ^For clarity: the values returned by
+** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of
 ** bytes in the string, not the number of characters.
 **
 ** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
 ** even empty strings, are always zero terminated.  ^The return
-** value from sqlite3_column_blob() for a zero-length BLOB is an arbitrary
-** pointer, possibly even a NULL pointer.
-**
-** ^The sqlite3_column_bytes16() routine is similar to sqlite3_column_bytes()
-** but leaves the result in UTF-16 in native byte order instead of UTF-8.
-** ^The zero terminator is not included in this count.
+** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.
 **
 ** ^The object returned by [sqlite3_column_value()] is an
 ** [unprotected sqlite3_value] object.  An unprotected sqlite3_value object
@@ -3662,10 +3736,10 @@
 ** used in the table for brevity and because they are familiar to most
 ** C programmers.
 **
-** ^Note that when type conversions occur, pointers returned by prior
+** Note that when type conversions occur, pointers returned by prior
 ** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
 ** sqlite3_column_text16() may be invalidated.
-** ^(Type conversions and pointer invalidations might occur
+** Type conversions and pointer invalidations might occur
 ** in the following cases:
 **
 ** <ul>
@@ -3678,22 +3752,22 @@
 ** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
 **      sqlite3_column_text() is called.  The content must be converted
 **      to UTF-8.</li>
-** </ul>)^
+** </ul>
 **
 ** ^Conversions between UTF-16be and UTF-16le are always done in place and do
 ** not invalidate a prior pointer, though of course the content of the buffer
-** that the prior pointer points to will have been modified.  Other kinds
+** that the prior pointer references will have been modified.  Other kinds
 ** of conversion are done in place when it is possible, but sometimes they
 ** are not possible and in those cases prior pointers are invalidated.
 **
-** ^(The safest and easiest to remember policy is to invoke these routines
+** The safest and easiest to remember policy is to invoke these routines
 ** in one of the following ways:
 **
 ** <ul>
 **  <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
 **  <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
 **  <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
-** </ul>)^
+** </ul>
 **
 ** In other words, you should call sqlite3_column_text(),
 ** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
@@ -3777,23 +3851,25 @@
 ** KEYWORDS: {application-defined SQL function}
 ** KEYWORDS: {application-defined SQL functions}
 **
-** ^These two functions (collectively known as "function creation routines")
+** ^These functions (collectively known as "function creation routines")
 ** are used to add SQL functions or aggregates or to redefine the behavior
-** of existing SQL functions or aggregates.  The only difference between the
-** two is that the second parameter, the name of the (scalar) function or
-** aggregate, is encoded in UTF-8 for sqlite3_create_function() and UTF-16
-** for sqlite3_create_function16().
+** of existing SQL functions or aggregates.  The only differences between
+** these routines are the text encoding expected for
+** the the second parameter (the name of the function being created)
+** and the presence or absence of a destructor callback for
+** the application data pointer.
 **
 ** ^The first parameter is the [database connection] to which the SQL
 ** function is to be added.  ^If an application uses more than one database
 ** connection then application-defined SQL functions must be added
 ** to each database connection separately.
 **
-** The second parameter is the name of the SQL function to be created or
-** redefined.  ^The length of the name is limited to 255 bytes, exclusive of
-** the zero-terminator.  Note that the name length limit is in bytes, not
-** characters.  ^Any attempt to create a function with a longer name
-** will result in [SQLITE_ERROR] being returned.
+** ^The second parameter is the name of the SQL function to be created or
+** redefined.  ^The length of the name is limited to 255 bytes in a UTF-8
+** representation, exclusive of the zero-terminator.  ^Note that the name
+** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes.  
+** ^Any attempt to create a function with a longer name
+** will result in [SQLITE_MISUSE] being returned.
 **
 ** ^The third parameter (nArg)
 ** is the number of arguments that the SQL function or
@@ -3803,10 +3879,10 @@
 ** parameter is less than -1 or greater than 127 then the behavior is
 ** undefined.
 **
-** The fourth parameter, eTextRep, specifies what
+** ^The fourth parameter, eTextRep, specifies what
 ** [SQLITE_UTF8 | text encoding] this SQL function prefers for
-** its parameters.  Any SQL function implementation should be able to work
-** work with UTF-8, UTF-16le, or UTF-16be.  But some implementations may be
+** its parameters.  Every SQL function implementation must be able to work
+** with UTF-8, UTF-16le, or UTF-16be.  But some implementations may be
 ** more efficient with one encoding than another.  ^An application may
 ** invoke sqlite3_create_function() or sqlite3_create_function16() multiple
 ** times with the same function but with different values of eTextRep.
@@ -3818,13 +3894,21 @@
 ** ^(The fifth parameter is an arbitrary pointer.  The implementation of the
 ** function can gain access to this pointer using [sqlite3_user_data()].)^
 **
-** The seventh, eighth and ninth parameters, xFunc, xStep and xFinal, are
+** ^The seventh, eighth and ninth parameters, xFunc, xStep and xFinal, are
 ** pointers to C-language functions that implement the SQL function or
 ** aggregate. ^A scalar SQL function requires an implementation of the xFunc
-** callback only; NULL pointers should be passed as the xStep and xFinal
+** callback only; NULL pointers must be passed as the xStep and xFinal
 ** parameters. ^An aggregate SQL function requires an implementation of xStep
-** and xFinal and NULL should be passed for xFunc. ^To delete an existing
-** SQL function or aggregate, pass NULL for all three function callbacks.
+** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing
+** SQL function or aggregate, pass NULL poiners for all three function
+** callbacks.
+**
+** ^If the tenth parameter to sqlite3_create_function_v2() is not NULL,
+** then it is invoked when the function is deleted, either by being
+** overloaded or when the database connection closes.
+** ^When the destructure callback of the tenth parameter is invoked, it
+** is passed a single argument which is a copy of the pointer which was
+** the fifth parameter to sqlite3_create_function_v2().
 **
 ** ^It is permitted to register multiple implementations of the same
 ** functions with the same name but with either differing numbers of
@@ -3840,11 +3924,6 @@
 ** between UTF8 and UTF16.
 **
 ** ^Built-in functions may be overloaded by new application-defined functions.
-** ^The first application-defined function with a given name overrides all
-** built-in functions in the same [database connection] with the same name.
-** ^Subsequent application-defined functions of the same name only override 
-** prior application-defined functions that are an exact match for the
-** number of parameters and preferred encoding.
 **
 ** ^An application-defined function is permitted to call other
 ** SQLite interfaces.  However, such calls must not
@@ -3871,6 +3950,17 @@
   void (*xStep)(sqlite3_context*,int,sqlite3_value**),
   void (*xFinal)(sqlite3_context*)
 );
+SQLITE_API int sqlite3_create_function_v2(
+  sqlite3 *db,
+  const char *zFunctionName,
+  int nArg,
+  int eTextRep,
+  void *pApp,
+  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
+  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
+  void (*xFinal)(sqlite3_context*),
+  void(*xDestroy)(void*)
+);
 
 /*
 ** CAPI3REF: Text Encodings
@@ -3965,7 +4055,7 @@
 /*
 ** CAPI3REF: Obtain Aggregate Function Context
 **
-** Implementions of aggregate SQL functions use this
+** Implementations of aggregate SQL functions use this
 ** routine to allocate memory for storing their state.
 **
 ** ^The first time the sqlite3_aggregate_context(C,N) routine is called 
@@ -4217,46 +4307,70 @@
 /*
 ** CAPI3REF: Define New Collating Sequences
 **
-** These functions are used to add new collation sequences to the
-** [database connection] specified as the first argument.
+** ^These functions add, remove, or modify a [collation] associated
+** with the [database connection] specified as the first argument.
 **
-** ^The name of the new collation sequence is specified as a UTF-8 string
+** ^The name of the collation is a UTF-8 string
 ** for sqlite3_create_collation() and sqlite3_create_collation_v2()
-** and a UTF-16 string for sqlite3_create_collation16(). ^In all cases
-** the name is passed as the second function argument.
+** and a UTF-16 string in native byte order for sqlite3_create_collation16().
+** ^Collation names that compare equal according to [sqlite3_strnicmp()] are
+** considered to be the same name.
 **
-** ^The third argument may be one of the constants [SQLITE_UTF8],
-** [SQLITE_UTF16LE], or [SQLITE_UTF16BE], indicating that the user-supplied
-** routine expects to be passed pointers to strings encoded using UTF-8,
-** UTF-16 little-endian, or UTF-16 big-endian, respectively. ^The
-** third argument might also be [SQLITE_UTF16] to indicate that the routine
-** expects pointers to be UTF-16 strings in the native byte order, or the
-** argument can be [SQLITE_UTF16_ALIGNED] if the
-** the routine expects pointers to 16-bit word aligned strings
-** of UTF-16 in the native byte order.
+** ^(The third argument (eTextRep) must be one of the constants:
+** <ul>
+** <li> [SQLITE_UTF8],
+** <li> [SQLITE_UTF16LE],
+** <li> [SQLITE_UTF16BE],
+** <li> [SQLITE_UTF16], or
+** <li> [SQLITE_UTF16_ALIGNED].
+** </ul>)^
+** ^The eTextRep argument determines the encoding of strings passed
+** to the collating function callback, xCallback.
+** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep
+** force strings to be UTF16 with native byte order.
+** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin
+** on an even byte address.
 **
-** A pointer to the user supplied routine must be passed as the fifth
-** argument.  ^If it is NULL, this is the same as deleting the collation
-** sequence (so that SQLite cannot call it anymore).
-** ^Each time the application supplied function is invoked, it is passed
-** as its first parameter a copy of the void* passed as the fourth argument
-** to sqlite3_create_collation() or sqlite3_create_collation16().
+** ^The fourth argument, pArg, is a application data pointer that is passed
+** through as the first argument to the collating function callback.
 **
-** ^The remaining arguments to the application-supplied routine are two strings,
-** each represented by a (length, data) pair and encoded in the encoding
-** that was passed as the third argument when the collation sequence was
-** registered.  The application defined collation routine should
-** return negative, zero or positive if the first string is less than,
-** equal to, or greater than the second string. i.e. (STRING1 - STRING2).
+** ^The fifth argument, xCallback, is a pointer to the collating function.
+** ^Multiple collating functions can be registered using the same name but
+** with different eTextRep parameters and SQLite will use whichever
+** function requires the least amount of data transformation.
+** ^If the xCallback argument is NULL then the collating function is
+** deleted.  ^When all collating functions having the same name are deleted,
+** that collation is no longer usable.
+**
+** ^The collating function callback is invoked with a copy of the pArg 
+** application data pointer and with two strings in the encoding specified
+** by the eTextRep argument.  The collating function must return an
+** integer that is negative, zero, or positive
+** if the first string is less than, equal to, or greater than the second,
+** respectively.  A collating function must alway return the same answer
+** given the same inputs.  If two or more collating functions are registered
+** to the same collation name (using different eTextRep values) then all
+** must give an equivalent answer when invoked with equivalent strings.
+** The collating function must obey the following properties for all
+** strings A, B, and C:
+**
+** <ol>
+** <li> If A==B then B==A.
+** <li> If A==B and B==C then A==C.
+** <li> If A&lt;B THEN B&gt;A.
+** <li> If A&lt;B and B&lt;C then A&lt;C.
+** </ol>
+**
+** If a collating function fails any of the above constraints and that
+** collating function is  registered and used, then the behavior of SQLite
+** is undefined.
 **
 ** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()
-** except that it takes an extra argument which is a destructor for
-** the collation.  ^The destructor is called when the collation is
-** destroyed and is passed a copy of the fourth parameter void* pointer
-** of the sqlite3_create_collation_v2().
-** ^Collations are destroyed when they are overridden by later calls to the
-** collation creation functions or when the [database connection] is closed
-** using [sqlite3_close()].
+** with the addition that the xDestroy callback is invoked on pArg when
+** the collating function is deleted.
+** ^Collating functions are deleted when they are overridden by later
+** calls to the collation creation functions or when the
+** [database connection] is closed using [sqlite3_close()].
 **
 ** See also:  [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
 */
@@ -4264,14 +4378,14 @@
   sqlite3*, 
   const char *zName, 
   int eTextRep, 
-  void*,
+  void *pArg,
   int(*xCompare)(void*,int,const void*,int,const void*)
 );
 SQLITE_API int sqlite3_create_collation_v2(
   sqlite3*, 
   const char *zName, 
   int eTextRep, 
-  void*,
+  void *pArg,
   int(*xCompare)(void*,int,const void*,int,const void*),
   void(*xDestroy)(void*)
 );
@@ -4279,7 +4393,7 @@
   sqlite3*, 
   const void *zName,
   int eTextRep, 
-  void*,
+  void *pArg,
   int(*xCompare)(void*,int,const void*,int,const void*)
 );
 
@@ -4368,16 +4482,19 @@
 /*
 ** CAPI3REF: Suspend Execution For A Short Time
 **
-** ^The sqlite3_sleep() function causes the current thread to suspend execution
+** The sqlite3_sleep() function causes the current thread to suspend execution
 ** for at least a number of milliseconds specified in its parameter.
 **
-** ^If the operating system does not support sleep requests with
+** If the operating system does not support sleep requests with
 ** millisecond time resolution, then the time will be rounded up to
-** the nearest second. ^The number of milliseconds of sleep actually
+** the nearest second. The number of milliseconds of sleep actually
 ** requested from the operating system is returned.
 **
 ** ^SQLite implements this interface by calling the xSleep()
-** method of the default [sqlite3_vfs] object.
+** method of the default [sqlite3_vfs] object.  If the xSleep() method
+** of the default VFS is not implemented correctly, or not implemented at
+** all, then the behavior of sqlite3_sleep() may deviate from the description
+** in the previous paragraphs.
 */
 SQLITE_API int sqlite3_sleep(int);
 
@@ -4599,40 +4716,73 @@
 ** pages to improve performance is an example of non-essential memory.
 ** ^sqlite3_release_memory() returns the number of bytes actually freed,
 ** which might be more or less than the amount requested.
+** ^The sqlite3_release_memory() routine is a no-op returning zero
+** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT].
 */
 SQLITE_API int sqlite3_release_memory(int);
 
 /*
 ** CAPI3REF: Impose A Limit On Heap Size
 **
-** ^The sqlite3_soft_heap_limit() interface places a "soft" limit
-** on the amount of heap memory that may be allocated by SQLite.
-** ^If an internal allocation is requested that would exceed the
-** soft heap limit, [sqlite3_release_memory()] is invoked one or
-** more times to free up some space before the allocation is performed.
+** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the
+** soft limit on the amount of heap memory that may be allocated by SQLite.
+** ^SQLite strives to keep heap memory utilization below the soft heap
+** limit by reducing the number of pages held in the page cache
+** as heap memory usages approaches the limit.
+** ^The soft heap limit is "soft" because even though SQLite strives to stay
+** below the limit, it will exceed the limit rather than generate
+** an [SQLITE_NOMEM] error.  In other words, the soft heap limit 
+** is advisory only.
 **
-** ^The limit is called "soft" because if [sqlite3_release_memory()]
-** cannot free sufficient memory to prevent the limit from being exceeded,
-** the memory is allocated anyway and the current operation proceeds.
+** ^The return value from sqlite3_soft_heap_limit64() is the size of
+** the soft heap limit prior to the call.  ^If the argument N is negative
+** then no change is made to the soft heap limit.  Hence, the current
+** size of the soft heap limit can be determined by invoking
+** sqlite3_soft_heap_limit64() with a negative argument.
 **
-** ^A negative or zero value for N means that there is no soft heap limit and
-** [sqlite3_release_memory()] will only be called when memory is exhausted.
-** ^The default value for the soft heap limit is zero.
+** ^If the argument N is zero then the soft heap limit is disabled.
 **
-** ^(SQLite makes a best effort to honor the soft heap limit.
-** But if the soft heap limit cannot be honored, execution will
-** continue without error or notification.)^  This is why the limit is
-** called a "soft" limit.  It is advisory only.
+** ^(The soft heap limit is not enforced in the current implementation
+** if one or more of following conditions are true:
 **
-** Prior to SQLite version 3.5.0, this routine only constrained the memory
-** allocated by a single thread - the same thread in which this routine
-** runs.  Beginning with SQLite version 3.5.0, the soft heap limit is
-** applied to all threads. The value specified for the soft heap limit
-** is an upper bound on the total memory allocation for all threads. In
-** version 3.5.0 there is no mechanism for limiting the heap usage for
-** individual threads.
+** <ul>
+** <li> The soft heap limit is set to zero.
+** <li> Memory accounting is disabled using a combination of the
+**      [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and
+**      the [SQLITE_DEFAULT_MEMSTATUS] compile-time option.
+** <li> An alternative page cache implementation is specifed using
+**      [sqlite3_config]([SQLITE_CONFIG_PCACHE],...).
+** <li> The page cache allocates from its own memory pool supplied
+**      by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than
+**      from the heap.
+** </ul>)^
+**
+** Beginning with SQLite version 3.7.3, the soft heap limit is enforced
+** regardless of whether or not the [SQLITE_ENABLE_MEMORY_MANAGEMENT]
+** compile-time option is invoked.  With [SQLITE_ENABLE_MEMORY_MANAGEMENT],
+** the soft heap limit is enforced on every memory allocation.  Without
+** [SQLITE_ENABLE_MEMORY_MANAGEMENT], the soft heap limit is only enforced
+** when memory is allocated by the page cache.  Testing suggests that because
+** the page cache is the predominate memory user in SQLite, most
+** applications will achieve adequate soft heap limit enforcement without
+** the use of [SQLITE_ENABLE_MEMORY_MANAGEMENT].
+**
+** The circumstances under which SQLite will enforce the soft heap limit may
+** changes in future releases of SQLite.
 */
-SQLITE_API void sqlite3_soft_heap_limit(int);
+SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N);
+
+/*
+** CAPI3REF: Deprecated Soft Heap Limit Interface
+** DEPRECATED
+**
+** This is a deprecated version of the [sqlite3_soft_heap_limit64()]
+** interface.  This routine is provided for historical compatibility
+** only.  All new applications should use the
+** [sqlite3_soft_heap_limit64()] interface rather than this one.
+*/
+SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N);
+
 
 /*
 ** CAPI3REF: Extract Metadata About A Column Of A Table
@@ -4756,34 +4906,47 @@
 SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
 
 /*
-** CAPI3REF: Automatically Load An Extensions
+** CAPI3REF: Automatically Load Statically Linked Extensions
 **
-** ^This API can be invoked at program startup in order to register
-** one or more statically linked extensions that will be available
-** to all new [database connections].
+** ^This interface causes the xEntryPoint() function to be invoked for
+** each new [database connection] that is created.  The idea here is that
+** xEntryPoint() is the entry point for a statically linked SQLite extension
+** that is to be automatically loaded into all new database connections.
 **
-** ^(This routine stores a pointer to the extension entry point
-** in an array that is obtained from [sqlite3_malloc()].  That memory
-** is deallocated by [sqlite3_reset_auto_extension()].)^
+** ^(Even though the function prototype shows that xEntryPoint() takes
+** no arguments and returns void, SQLite invokes xEntryPoint() with three
+** arguments and expects and integer result as if the signature of the
+** entry point where as follows:
 **
-** ^This function registers an extension entry point that is
-** automatically invoked whenever a new [database connection]
-** is opened using [sqlite3_open()], [sqlite3_open16()],
-** or [sqlite3_open_v2()].
-** ^Duplicate extensions are detected so calling this routine
-** multiple times with the same extension is harmless.
-** ^Automatic extensions apply across all threads.
+** <blockquote><pre>
+** &nbsp;  int xEntryPoint(
+** &nbsp;    sqlite3 *db,
+** &nbsp;    const char **pzErrMsg,
+** &nbsp;    const struct sqlite3_api_routines *pThunk
+** &nbsp;  );
+** </pre></blockquote>)^
+**
+** If the xEntryPoint routine encounters an error, it should make *pzErrMsg
+** point to an appropriate error message (obtained from [sqlite3_mprintf()])
+** and return an appropriate [error code].  ^SQLite ensures that *pzErrMsg
+** is NULL before calling the xEntryPoint().  ^SQLite will invoke
+** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns.  ^If any
+** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()],
+** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail.
+**
+** ^Calling sqlite3_auto_extension(X) with an entry point X that is already
+** on the list of automatic extensions is a harmless no-op. ^No entry point
+** will be called more than once for each database connection that is opened.
+**
+** See also: [sqlite3_reset_auto_extension()].
 */
 SQLITE_API int sqlite3_auto_extension(void (*xEntryPoint)(void));
 
 /*
 ** CAPI3REF: Reset Automatic Extension Loading
 **
-** ^(This function disables all previously registered automatic
-** extensions. It undoes the effect of all prior
-** [sqlite3_auto_extension()] calls.)^
-**
-** ^This function disables automatic extensions in all threads.
+** ^This interface disables all automatic extensions previously
+** registered using [sqlite3_auto_extension()].
 */
 SQLITE_API void sqlite3_reset_auto_extension(void);
 
@@ -4854,7 +5017,8 @@
 ** CAPI3REF: Virtual Table Indexing Information
 ** KEYWORDS: sqlite3_index_info
 **
-** The sqlite3_index_info structure and its substructures is used to
+** The sqlite3_index_info structure and its substructures is used as part
+** of the [virtual table] interface to
 ** pass information into and receive the reply from the [xBestIndex]
 ** method of a [virtual table module].  The fields under **Inputs** are the
 ** inputs to xBestIndex and are read-only.  xBestIndex inserts its
@@ -4862,10 +5026,12 @@
 **
 ** ^(The aConstraint[] array records WHERE clause constraints of the form:
 **
-** <pre>column OP expr</pre>
+** <blockquote>column OP expr</blockquote>
 **
 ** where OP is =, &lt;, &lt;=, &gt;, or &gt;=.)^  ^(The particular operator is
-** stored in aConstraint[].op.)^  ^(The index of the column is stored in
+** stored in aConstraint[].op using one of the
+** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^
+** ^(The index of the column is stored in
 ** aConstraint[].iColumn.)^  ^(aConstraint[].usable is TRUE if the
 ** expr on the right-hand side can be evaluated (and thus the constraint
 ** is usable) and false if it cannot.)^
@@ -4925,6 +5091,15 @@
   int orderByConsumed;       /* True if output is already ordered */
   double estimatedCost;      /* Estimated cost of using this index */
 };
+
+/*
+** CAPI3REF: Virtual Table Constraint Operator Codes
+**
+** These macros defined the allowed values for the
+** [sqlite3_index_info].aConstraint[].op field.  Each value represents
+** an operator that is part of a constraint term in the wHERE clause of
+** a query that uses a [virtual table].
+*/
 #define SQLITE_INDEX_CONSTRAINT_EQ    2
 #define SQLITE_INDEX_CONSTRAINT_GT    4
 #define SQLITE_INDEX_CONSTRAINT_LE    8
@@ -5410,7 +5585,7 @@
 **
 ** ^The xMutexInit method defined by this structure is invoked as
 ** part of system initialization by the sqlite3_initialize() function.
-** ^The xMutexInit routine is calle by SQLite exactly once for each
+** ^The xMutexInit routine is called by SQLite exactly once for each
 ** effective call to [sqlite3_initialize()].
 **
 ** ^The xMutexEnd method defined by this structure is invoked as
@@ -5443,7 +5618,7 @@
 ** it is passed a NULL pointer).
 **
 ** The xMutexInit() method must be threadsafe.  ^It must be harmless to
-** invoke xMutexInit() mutiple times within the same process and without
+** invoke xMutexInit() multiple times within the same process and without
 ** intervening calls to xMutexEnd().  Second and subsequent calls to
 ** xMutexInit() must be no-ops.
 **
@@ -5607,13 +5782,14 @@
 #define SQLITE_TESTCTRL_OPTIMIZATIONS           15
 #define SQLITE_TESTCTRL_ISKEYWORD               16
 #define SQLITE_TESTCTRL_PGHDRSZ                 17
-#define SQLITE_TESTCTRL_LAST                    17
+#define SQLITE_TESTCTRL_SCRATCHMALLOC           18
+#define SQLITE_TESTCTRL_LAST                    18
 
 /*
 ** CAPI3REF: SQLite Runtime Status
 **
 ** ^This interface is used to retrieve runtime status information
-** about the preformance of SQLite, and optionally to reset various
+** about the performance of SQLite, and optionally to reset various
 ** highwater marks.  ^The first argument is an integer code for
 ** the specific parameter to measure.  ^(Recognized integer codes
 ** are of the form [SQLITE_STATUS_MEMORY_USED | SQLITE_STATUS_...].)^
@@ -5626,7 +5802,7 @@
 ** ^(Other parameters record only the highwater mark and not the current
 ** value.  For these latter parameters nothing is written into *pCurrent.)^
 **
-** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a
+** ^The sqlite3_status() routine returns SQLITE_OK on success and a
 ** non-zero [error code] on failure.
 **
 ** This routine is threadsafe but is not atomic.  This routine can be
@@ -5665,6 +5841,9 @@
 ** *pHighwater parameter to [sqlite3_status()] is of interest.  
 ** The value written into the *pCurrent parameter is undefined.</dd>)^
 **
+** ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt>
+** <dd>This parameter records the number of separate memory allocations.</dd>)^
+**
 ** ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt>
 ** <dd>This parameter returns the number of pages used out of the
 ** [pagecache memory allocator] that was configured using 
@@ -5673,7 +5852,7 @@
 **
 ** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
 ** <dd>This parameter returns the number of bytes of page cache
-** allocation which could not be statisfied by the [SQLITE_CONFIG_PAGECACHE]
+** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE]
 ** buffer and where forced to overflow to [sqlite3_malloc()].  The
 ** returned value includes allocations that overflowed because they
 ** where too large (they were larger than the "sz" parameter to
@@ -5696,7 +5875,7 @@
 **
 ** ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
 ** <dd>This parameter returns the number of bytes of scratch memory
-** allocation which could not be statisfied by the [SQLITE_CONFIG_SCRATCH]
+** allocation which could not be satisfied by the [SQLITE_CONFIG_SCRATCH]
 ** buffer and where forced to overflow to [sqlite3_malloc()].  The values
 ** returned include overflows because the requested allocation was too
 ** larger (that is, because the requested allocation was larger than the
@@ -5726,6 +5905,7 @@
 #define SQLITE_STATUS_PARSER_STACK         6
 #define SQLITE_STATUS_PAGECACHE_SIZE       7
 #define SQLITE_STATUS_SCRATCH_SIZE         8
+#define SQLITE_STATUS_MALLOC_COUNT         9
 
 /*
 ** CAPI3REF: Database Connection Status
@@ -5735,7 +5915,7 @@
 ** database connection object to be interrogated.  ^The second argument
 ** is an integer constant, taken from the set of
 ** [SQLITE_DBSTATUS_LOOKASIDE_USED | SQLITE_DBSTATUS_*] macros, that
-** determiness the parameter to interrogate.  The set of 
+** determines the parameter to interrogate.  The set of 
 ** [SQLITE_DBSTATUS_LOOKASIDE_USED | SQLITE_DBSTATUS_*] macros is likely
 ** to grow in future releases of SQLite.
 **
@@ -5744,6 +5924,9 @@
 ** the resetFlg is true, then the highest instantaneous value is
 ** reset back down to the current value.
 **
+** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a
+** non-zero [error code] on failure.
+**
 ** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
 */
 SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
@@ -5765,16 +5948,33 @@
 ** <dd>This parameter returns the number of lookaside memory slots currently
 ** checked out.</dd>)^
 **
-** <dt>SQLITE_DBSTATUS_CACHE_USED</dt>
-** <dd>^This parameter returns the approximate number of of bytes of heap
-** memory used by all pager caches associated with the database connection.
+** ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt>
+** <dd>This parameter returns the approximate number of of bytes of heap
+** memory used by all pager caches associated with the database connection.)^
 ** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0.
-** checked out.</dd>)^
+**
+** ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt>
+** <dd>This parameter returns the approximate number of of bytes of heap
+** memory used to store the schema for all databases associated
+** with the connection - main, temp, and any [ATTACH]-ed databases.)^ 
+** ^The full amount of memory used by the schemas is reported, even if the
+** schema memory is shared with other database connections due to
+** [shared cache mode] being enabled.
+** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0.
+**
+** ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt>
+** <dd>This parameter returns the approximate number of of bytes of heap
+** and lookaside memory used by all prepared statements associated with
+** the database connection.)^
+** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0.
+** </dd>
 ** </dl>
 */
 #define SQLITE_DBSTATUS_LOOKASIDE_USED     0
 #define SQLITE_DBSTATUS_CACHE_USED         1
-#define SQLITE_DBSTATUS_MAX                1   /* Largest defined DBSTATUS */
+#define SQLITE_DBSTATUS_SCHEMA_USED        2
+#define SQLITE_DBSTATUS_STMT_USED          3
+#define SQLITE_DBSTATUS_MAX                3   /* Largest defined DBSTATUS */
 
 
 /*
@@ -5853,32 +6053,42 @@
 **
 ** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE], ...) interface can
 ** register an alternative page cache implementation by passing in an 
-** instance of the sqlite3_pcache_methods structure.)^ The majority of the 
-** heap memory used by SQLite is used by the page cache to cache data read 
-** from, or ready to be written to, the database file. By implementing a 
-** custom page cache using this API, an application can control more 
-** precisely the amount of memory consumed by SQLite, the way in which 
+** instance of the sqlite3_pcache_methods structure.)^
+** In many applications, most of the heap memory allocated by 
+** SQLite is used for the page cache.
+** By implementing a 
+** custom page cache using this API, an application can better control
+** the amount of memory consumed by SQLite, the way in which 
 ** that memory is allocated and released, and the policies used to 
 ** determine exactly which parts of a database file are cached and for 
 ** how long.
 **
+** The alternative page cache mechanism is an
+** extreme measure that is only needed by the most demanding applications.
+** The built-in page cache is recommended for most uses.
+**
 ** ^(The contents of the sqlite3_pcache_methods structure are copied to an
 ** internal buffer by SQLite within the call to [sqlite3_config].  Hence
 ** the application may discard the parameter after the call to
 ** [sqlite3_config()] returns.)^
 **
-** ^The xInit() method is called once for each call to [sqlite3_initialize()]
+** ^(The xInit() method is called once for each effective 
+** call to [sqlite3_initialize()])^
 ** (usually only once during the lifetime of the process). ^(The xInit()
 ** method is passed a copy of the sqlite3_pcache_methods.pArg value.)^
-** ^The xInit() method can set up up global structures and/or any mutexes
+** The intent of the xInit() method is to set up global data structures 
 ** required by the custom page cache implementation. 
+** ^(If the xInit() method is NULL, then the 
+** built-in default page cache is used instead of the application defined
+** page cache.)^
 **
-** ^The xShutdown() method is called from within [sqlite3_shutdown()], 
-** if the application invokes this API. It can be used to clean up 
+** ^The xShutdown() method is called by [sqlite3_shutdown()].
+** It can be used to clean up 
 ** any outstanding resources before process shutdown, if required.
+** ^The xShutdown() method may be NULL.
 **
-** ^SQLite holds a [SQLITE_MUTEX_RECURSIVE] mutex when it invokes
-** the xInit method, so the xInit method need not be threadsafe.  ^The
+** ^SQLite automatically serializes calls to the xInit method,
+** so the xInit method need not be threadsafe.  ^The
 ** xShutdown method is only called from [sqlite3_shutdown()] so it does
 ** not need to be threadsafe either.  All other methods must be threadsafe
 ** in multithreaded applications.
@@ -5886,47 +6096,50 @@
 ** ^SQLite will never invoke xInit() more than once without an intervening
 ** call to xShutdown().
 **
-** ^The xCreate() method is used to construct a new cache instance.  SQLite
-** will typically create one cache instance for each open database file,
+** ^SQLite invokes the xCreate() method to construct a new cache instance.
+** SQLite will typically create one cache instance for each open database file,
 ** though this is not guaranteed. ^The
 ** first parameter, szPage, is the size in bytes of the pages that must
 ** be allocated by the cache.  ^szPage will not be a power of two.  ^szPage
 ** will the page size of the database file that is to be cached plus an
-** increment (here called "R") of about 100 or 200.  ^SQLite will use the
+** increment (here called "R") of about 100 or 200.  SQLite will use the
 ** extra R bytes on each page to store metadata about the underlying
 ** database page on disk.  The value of R depends
 ** on the SQLite version, the target platform, and how SQLite was compiled.
 ** ^R is constant for a particular build of SQLite.  ^The second argument to
 ** xCreate(), bPurgeable, is true if the cache being created will
 ** be used to cache database pages of a file stored on disk, or
-** false if it is used for an in-memory database. ^The cache implementation
+** false if it is used for an in-memory database. The cache implementation
 ** does not have to do anything special based with the value of bPurgeable;
 ** it is purely advisory.  ^On a cache where bPurgeable is false, SQLite will
 ** never invoke xUnpin() except to deliberately delete a page.
-** ^In other words, a cache created with bPurgeable set to false will
+** ^In other words, calls to xUnpin() on a cache with bPurgeable set to
+** false will always have the "discard" flag set to true.  
+** ^Hence, a cache created with bPurgeable false will
 ** never contain any unpinned pages.
 **
 ** ^(The xCachesize() method may be called at any time by SQLite to set the
 ** suggested maximum cache-size (number of pages stored by) the cache
 ** instance passed as the first argument. This is the value configured using
-** the SQLite "[PRAGMA cache_size]" command.)^  ^As with the bPurgeable
+** the SQLite "[PRAGMA cache_size]" command.)^  As with the bPurgeable
 ** parameter, the implementation is not required to do anything with this
 ** value; it is advisory only.
 **
-** ^The xPagecount() method should return the number of pages currently
-** stored in the cache.
+** The xPagecount() method must return the number of pages currently
+** stored in the cache, both pinned and unpinned.
 ** 
-** ^The xFetch() method is used to fetch a page and return a pointer to it. 
-** ^A 'page', in this context, is a buffer of szPage bytes aligned at an
-** 8-byte boundary. ^The page to be fetched is determined by the key. ^The
-** mimimum key value is 1. After it has been retrieved using xFetch, the page 
+** The xFetch() method locates a page in the cache and returns a pointer to 
+** the page, or a NULL pointer.
+** A "page", in this context, means a buffer of szPage bytes aligned at an
+** 8-byte boundary. The page to be fetched is determined by the key. ^The
+** mimimum key value is 1.  After it has been retrieved using xFetch, the page 
 ** is considered to be "pinned".
 **
-** ^If the requested page is already in the page cache, then the page cache
+** If the requested page is already in the page cache, then the page cache
 ** implementation must return a pointer to the page buffer with its content
-** intact.  ^(If the requested page is not already in the cache, then the
-** behavior of the cache implementation is determined by the value of the
-** createFlag parameter passed to xFetch, according to the following table:
+** intact.  If the requested page is not already in the cache, then the
+** behavior of the cache implementation should use the value of the createFlag
+** parameter to help it determined what action to take:
 **
 ** <table border=1 width=85% align=center>
 ** <tr><th> createFlag <th> Behaviour when page is not already in cache
@@ -5935,36 +6148,35 @@
 **                 Otherwise return NULL.
 ** <tr><td> 2 <td> Make every effort to allocate a new page.  Only return
 **                 NULL if allocating a new page is effectively impossible.
-** </table>)^
+** </table>
 **
-** SQLite will normally invoke xFetch() with a createFlag of 0 or 1.  If
-** a call to xFetch() with createFlag==1 returns NULL, then SQLite will
+** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1.  SQLite
+** will only use a createFlag of 2 after a prior call with a createFlag of 1
+** failed.)^  In between the to xFetch() calls, SQLite may
 ** attempt to unpin one or more cache pages by spilling the content of
-** pinned pages to disk and synching the operating system disk cache. After
-** attempting to unpin pages, the xFetch() method will be invoked again with
-** a createFlag of 2.
+** pinned pages to disk and synching the operating system disk cache.
 **
 ** ^xUnpin() is called by SQLite with a pointer to a currently pinned page
-** as its second argument. ^(If the third parameter, discard, is non-zero,
-** then the page should be evicted from the cache. In this case SQLite 
-** assumes that the next time the page is retrieved from the cache using
-** the xFetch() method, it will be zeroed.)^ ^If the discard parameter is
-** zero, then the page is considered to be unpinned. ^The cache implementation
+** as its second argument.  If the third parameter, discard, is non-zero,
+** then the page must be evicted from the cache.
+** ^If the discard parameter is
+** zero, then the page may be discarded or retained at the discretion of
+** page cache implementation. ^The page cache implementation
 ** may choose to evict unpinned pages at any time.
 **
-** ^(The cache is not required to perform any reference counting. A single 
+** The cache must not perform any reference counting. A single 
 ** call to xUnpin() unpins the page regardless of the number of prior calls 
-** to xFetch().)^
+** to xFetch().
 **
-** ^The xRekey() method is used to change the key value associated with the
-** page passed as the second argument from oldKey to newKey. ^If the cache
-** previously contains an entry associated with newKey, it should be
+** The xRekey() method is used to change the key value associated with the
+** page passed as the second argument. If the cache
+** previously contains an entry associated with newKey, it must be
 ** discarded. ^Any prior cache entry associated with newKey is guaranteed not
 ** to be pinned.
 **
-** ^When SQLite calls the xTruncate() method, the cache must discard all
+** When SQLite calls the xTruncate() method, the cache must discard all
 ** existing cache entries with page numbers (keys) greater than or equal
-** to the value of the iLimit parameter passed to xTruncate(). ^If any
+** to the value of the iLimit parameter passed to xTruncate(). If any
 ** of these pages are pinned, they are implicitly unpinned, meaning that
 ** they can be safely discarded.
 **
@@ -6140,7 +6352,7 @@
 **
 ** ^Each call to sqlite3_backup_step() sets two values inside
 ** the [sqlite3_backup] object: the number of pages still to be backed
-** up and the total number of pages in the source databae file.
+** up and the total number of pages in the source database file.
 ** The sqlite3_backup_remaining() and sqlite3_backup_pagecount() interfaces
 ** retrieve these two values, respectively.
 **
@@ -6236,7 +6448,7 @@
 ** blocked connection already has a registered unlock-notify callback,
 ** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is
 ** called with a NULL pointer as its second argument, then any existing
-** unlock-notify callback is cancelled. ^The blocked connections 
+** unlock-notify callback is canceled. ^The blocked connections 
 ** unlock-notify callback may also be canceled by closing the blocked
 ** connection using [sqlite3_close()].
 **
@@ -6318,7 +6530,7 @@
 **
 ** ^The [sqlite3_strnicmp()] API allows applications and extensions to
 ** compare the contents of two buffers containing UTF-8 strings in a
-** case-indendent fashion, using the same definition of case independence 
+** case-independent fashion, using the same definition of case independence 
 ** that SQLite uses internally when comparing identifiers.
 */
 SQLITE_API int sqlite3_strnicmp(const char *, const char *, int);
@@ -6442,6 +6654,62 @@
 #endif
 #endif
 
+/*
+** 2010 August 30
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+*/
+
+#ifndef _SQLITE3RTREE_H_
+#define _SQLITE3RTREE_H_
+
+
+#if 0
+extern "C" {
+#endif
+
+typedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry;
+
+/*
+** Register a geometry callback named zGeom that can be used as part of an
+** R-Tree geometry query as follows:
+**
+**   SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zGeom(... params ...)
+*/
+SQLITE_API int sqlite3_rtree_geometry_callback(
+  sqlite3 *db,
+  const char *zGeom,
+  int (*xGeom)(sqlite3_rtree_geometry *, int nCoord, double *aCoord, int *pRes),
+  void *pContext
+);
+
+
+/*
+** A pointer to a structure of the following type is passed as the first
+** argument to callbacks registered using rtree_geometry_callback().
+*/
+struct sqlite3_rtree_geometry {
+  void *pContext;                 /* Copy of pContext passed to s_r_g_c() */
+  int nParam;                     /* Size of array aParam[] */
+  double *aParam;                 /* Parameters passed to SQL geom function */
+  void *pUser;                    /* Callback implementation user data */
+  void (*xDelUser)(void *);       /* Called by SQLite to clean up pUser */
+};
+
+
+#if 0
+}  /* end of the 'extern "C"' block */
+#endif
+
+#endif  /* ifndef _SQLITE3RTREE_H_ */
+
 
 /************** End of sqlite3.h *********************************************/
 /************** Continuing where we left off in sqliteInt.h ******************/
@@ -7012,6 +7280,7 @@
 typedef struct ExprList ExprList;
 typedef struct ExprSpan ExprSpan;
 typedef struct FKey FKey;
+typedef struct FuncDestructor FuncDestructor;
 typedef struct FuncDef FuncDef;
 typedef struct FuncDefHash FuncDefHash;
 typedef struct IdList IdList;
@@ -7118,12 +7387,11 @@
 ** NOTE:  These values must match the corresponding PAGER_ values in
 ** pager.h.
 */
-#define BTREE_OMIT_JOURNAL  1  /* Do not use journal.  No argument */
+#define BTREE_OMIT_JOURNAL  1  /* Do not create or use a rollback journal */
 #define BTREE_NO_READLOCK   2  /* Omit readlocks on readonly files */
-#define BTREE_MEMORY        4  /* In-memory DB.  No argument */
-#define BTREE_READONLY      8  /* Open the database in read-only mode */
-#define BTREE_READWRITE    16  /* Open for both reading and writing */
-#define BTREE_CREATE       32  /* Create the database if it does not exist */
+#define BTREE_MEMORY        4  /* This is an in-memory DB */
+#define BTREE_SINGLE        8  /* The file contains at most 1 b-tree */
+#define BTREE_UNORDERED    16  /* Use of a hash implementation is OK */
 
 SQLITE_PRIVATE int sqlite3BtreeClose(Btree*);
 SQLITE_PRIVATE int sqlite3BtreeSetCacheSize(Btree*,int);
@@ -7159,11 +7427,17 @@
 SQLITE_PRIVATE int sqlite3BtreeIncrVacuum(Btree *);
 
 /* The flags parameter to sqlite3BtreeCreateTable can be the bitwise OR
-** of the following flags:
+** of the flags shown below.
+**
+** Every SQLite table must have either BTREE_INTKEY or BTREE_BLOBKEY set.
+** With BTREE_INTKEY, the table key is a 64-bit integer and arbitrary data
+** is stored in the leaves.  (BTREE_INTKEY is used for SQL tables.)  With
+** BTREE_BLOBKEY, the key is an arbitrary BLOB and no content is stored
+** anywhere - the key is the content.  (BTREE_BLOBKEY is used for SQL
+** indices.)
 */
 #define BTREE_INTKEY     1    /* Table has only 64-bit signed integer keys */
-#define BTREE_ZERODATA   2    /* Table has keys only - no data */
-#define BTREE_LEAFDATA   4    /* Data stored in leaves only.  Implies INTKEY */
+#define BTREE_BLOBKEY    2    /* Table has keys only - no data */
 
 SQLITE_PRIVATE int sqlite3BtreeDropTable(Btree*, int, int*);
 SQLITE_PRIVATE int sqlite3BtreeClearTable(Btree*, int, int*);
@@ -7252,6 +7526,10 @@
 SQLITE_PRIVATE void sqlite3BtreeCursorList(Btree*);
 #endif
 
+#ifndef SQLITE_OMIT_WAL
+SQLITE_PRIVATE   int sqlite3BtreeCheckpoint(Btree*);
+#endif
+
 /*
 ** If we are not using shared cache, then there is no need to
 ** use mutexes to access the BtShared structures.  So make the
@@ -7381,8 +7659,8 @@
   int nOp;                      /* Elements in aOp[] */
   int nMem;                     /* Number of memory cells required */
   int nCsr;                     /* Number of cursors required */
-  int nRef;                     /* Number of pointers to this structure */
   void *token;                  /* id that may be used to recursive triggers */
+  SubProgram *pNext;            /* Next sub-program already visited */
 };
 
 /*
@@ -7670,6 +7948,7 @@
 SQLITE_PRIVATE int sqlite3VdbeMakeLabel(Vdbe*);
 SQLITE_PRIVATE void sqlite3VdbeRunOnlyOnce(Vdbe*);
 SQLITE_PRIVATE void sqlite3VdbeDelete(Vdbe*);
+SQLITE_PRIVATE void sqlite3VdbeDeleteObject(sqlite3*,Vdbe*);
 SQLITE_PRIVATE void sqlite3VdbeMakeReady(Vdbe*,int,int,int,int,int,int);
 SQLITE_PRIVATE int sqlite3VdbeFinalize(Vdbe*);
 SQLITE_PRIVATE void sqlite3VdbeResolveLabel(Vdbe*, int);
@@ -7687,7 +7966,6 @@
 SQLITE_PRIVATE void sqlite3VdbeSetSql(Vdbe*, const char *z, int n, int);
 SQLITE_PRIVATE void sqlite3VdbeSwap(Vdbe*,Vdbe*);
 SQLITE_PRIVATE VdbeOp *sqlite3VdbeTakeOpArray(Vdbe*, int*, int*);
-SQLITE_PRIVATE void sqlite3VdbeProgramDelete(sqlite3 *, SubProgram *, int);
 SQLITE_PRIVATE sqlite3_value *sqlite3VdbeGetValue(Vdbe*, int, u8);
 SQLITE_PRIVATE void sqlite3VdbeSetVarmask(Vdbe*, int);
 #ifndef SQLITE_OMIT_TRACE
@@ -7698,6 +7976,10 @@
 SQLITE_PRIVATE void sqlite3VdbeDeleteUnpackedRecord(UnpackedRecord*);
 SQLITE_PRIVATE int sqlite3VdbeRecordCompare(int,const void*,UnpackedRecord*);
 
+#ifndef SQLITE_OMIT_TRIGGER
+SQLITE_PRIVATE void sqlite3VdbeLinkSubProgram(Vdbe *, SubProgram *);
+#endif
+
 
 #ifndef NDEBUG
 SQLITE_PRIVATE   void sqlite3VdbeComment(Vdbe*, const char*, ...);
@@ -7776,6 +8058,7 @@
 */
 #define PAGER_OMIT_JOURNAL  0x0001    /* Do not use a rollback journal */
 #define PAGER_NO_READLOCK   0x0002    /* Omit readlocks on readonly files */
+#define PAGER_MEMORY        0x0004    /* In-memory database */
 
 /*
 ** Valid values for the second argument to sqlite3PagerLockingMode().
@@ -7816,7 +8099,7 @@
 
 /* Functions used to configure a Pager object. */
 SQLITE_PRIVATE void sqlite3PagerSetBusyhandler(Pager*, int(*)(void *), void *);
-SQLITE_PRIVATE int sqlite3PagerSetPagesize(Pager*, u16*, int);
+SQLITE_PRIVATE int sqlite3PagerSetPagesize(Pager*, u32*, int);
 SQLITE_PRIVATE int sqlite3PagerMaxPageCount(Pager*, int);
 SQLITE_PRIVATE void sqlite3PagerSetCachesize(Pager*, int);
 SQLITE_PRIVATE void sqlite3PagerSetSafetyLevel(Pager*,int,int);
@@ -7843,9 +8126,10 @@
 SQLITE_PRIVATE void *sqlite3PagerGetExtra(DbPage *); 
 
 /* Functions used to manage pager transactions and savepoints. */
-SQLITE_PRIVATE int sqlite3PagerPagecount(Pager*, int*);
+SQLITE_PRIVATE void sqlite3PagerPagecount(Pager*, int*);
 SQLITE_PRIVATE int sqlite3PagerBegin(Pager*, int exFlag, int);
 SQLITE_PRIVATE int sqlite3PagerCommitPhaseOne(Pager*,const char *zMaster, int);
+SQLITE_PRIVATE int sqlite3PagerExclusiveLock(Pager*);
 SQLITE_PRIVATE int sqlite3PagerSync(Pager *pPager);
 SQLITE_PRIVATE int sqlite3PagerCommitPhaseTwo(Pager*);
 SQLITE_PRIVATE int sqlite3PagerRollback(Pager*);
@@ -8309,11 +8593,10 @@
 #define SQLITE_FCNTL_DB_UNCHANGED 0xca093fa0
 SQLITE_PRIVATE int sqlite3OsSectorSize(sqlite3_file *id);
 SQLITE_PRIVATE int sqlite3OsDeviceCharacteristics(sqlite3_file *id);
-SQLITE_PRIVATE int sqlite3OsShmOpen(sqlite3_file *id);
+SQLITE_PRIVATE int sqlite3OsShmMap(sqlite3_file *,int,int,int,void volatile **);
 SQLITE_PRIVATE int sqlite3OsShmLock(sqlite3_file *id, int, int, int);
 SQLITE_PRIVATE void sqlite3OsShmBarrier(sqlite3_file *id);
-SQLITE_PRIVATE int sqlite3OsShmClose(sqlite3_file *id, int);
-SQLITE_PRIVATE int sqlite3OsShmMap(sqlite3_file *,int,int,int,void volatile **);
+SQLITE_PRIVATE int sqlite3OsShmUnmap(sqlite3_file *id, int);
 
 /* 
 ** Functions for accessing sqlite3_vfs methods 
@@ -8410,8 +8693,8 @@
 #define sqlite3_mutex_enter(X)
 #define sqlite3_mutex_try(X)      SQLITE_OK
 #define sqlite3_mutex_leave(X)
-#define sqlite3_mutex_held(X)     1
-#define sqlite3_mutex_notheld(X)  1
+#define sqlite3_mutex_held(X)     ((void)(X),1)
+#define sqlite3_mutex_notheld(X)  ((void)(X),1)
 #define sqlite3MutexAlloc(X)      ((sqlite3_mutex*)8)
 #define sqlite3MutexInit()        SQLITE_OK
 #define sqlite3MutexEnd()
@@ -8438,14 +8721,6 @@
 
 /*
 ** An instance of the following structure stores a database schema.
-**
-** If there are no virtual tables configured in this schema, the
-** Schema.db variable is set to NULL. After the first virtual table
-** has been added, it is set to point to the database connection 
-** used to create the connection. Once a virtual table has been
-** added to the Schema structure and the Schema.db variable populated, 
-** only that database connection may use the Schema to prepare 
-** statements.
 */
 struct Schema {
   int schema_cookie;   /* Database schema version number for this file */
@@ -8458,9 +8733,6 @@
   u8 enc;              /* Text encoding used by this database */
   u16 flags;           /* Flags associated with this schema */
   int cache_size;      /* Number of pages to use in the cache */
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-  sqlite3 *db;         /* "Owner" connection. See comment above */
-#endif
 };
 
 /*
@@ -8574,7 +8846,6 @@
   u8 temp_store;                /* 1: file 2: memory 0: default */
   u8 mallocFailed;              /* True if we have seen a malloc failure */
   u8 dfltLockMode;              /* Default locking-mode for attached dbs */
-  u8 dfltJournalMode;           /* Default journal mode for attached dbs */
   signed char nextAutovac;      /* Autovac setting after VACUUM if >=0 */
   u8 suppressErr;               /* Do not issue error messages if true */
   int nextPagesize;             /* Pagesize after VACUUM if >0 */
@@ -8649,6 +8920,7 @@
   int nStatement;               /* Number of nested statement-transactions  */
   u8 isTransactionSavepoint;    /* True if the outermost savepoint is a TS */
   i64 nDeferredCons;            /* Net deferred constraints this transaction. */
+  int *pnBytesFreed;            /* If not NULL, increment this in DbFree() */
 
 #ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
   /* The following variables are all protected by the STATIC_MASTER 
@@ -8744,6 +9016,27 @@
   void (*xFinalize)(sqlite3_context*);                /* Aggregate finalizer */
   char *zName;         /* SQL name of the function. */
   FuncDef *pHash;      /* Next with a different name but the same hash */
+  FuncDestructor *pDestructor;   /* Reference counted destructor function */
+};
+
+/*
+** This structure encapsulates a user-function destructor callback (as
+** configured using create_function_v2()) and a reference counter. When
+** create_function_v2() is called to create a function with a destructor,
+** a single object of this type is allocated. FuncDestructor.nRef is set to 
+** the number of FuncDef objects created (either 1 or 3, depending on whether
+** or not the specified encoding is SQLITE_ANY). The FuncDef.pDestructor
+** member of each of the new FuncDef objects is set to point to the allocated
+** FuncDestructor.
+**
+** Thereafter, when one of the FuncDef objects is deleted, the reference
+** count on this object is decremented. When it reaches 0, the destructor
+** is invoked and the FuncDestructor structure freed.
+*/
+struct FuncDestructor {
+  int nRef;
+  void (*xDestroy)(void *);
+  void *pUserData;
 };
 
 /*
@@ -9006,13 +9299,13 @@
 ** of a SELECT statement.
 */
 struct Table {
-  sqlite3 *dbMem;      /* DB connection used for lookaside allocations. */
   char *zName;         /* Name of the table or view */
   int iPKey;           /* If not negative, use aCol[iPKey] as the primary key */
   int nCol;            /* Number of columns in this table */
   Column *aCol;        /* Information about each column */
   Index *pIndex;       /* List of SQL indexes on this table. */
   int tnum;            /* Root BTree node for this table (see note above) */
+  unsigned nRowEst;    /* Estimated rows in table - from sqlite_stat1 table */
   Select *pSelect;     /* NULL for tables.  Points to definition if a view. */
   u16 nRef;            /* Number of pointers to this Table */
   u8 tabFlags;         /* Mask of TF_* values */
@@ -9143,9 +9436,9 @@
 */
 struct KeyInfo {
   sqlite3 *db;        /* The database connection */
-  u8 enc;             /* Text encoding - one of the TEXT_Utf* values */
+  u8 enc;             /* Text encoding - one of the SQLITE_UTF* values */
   u16 nField;         /* Number of entries in aColl[] */
-  u8 *aSortOrder;     /* If defined an aSortOrder[i] is true, sort DESC */
+  u8 *aSortOrder;     /* Sort order for each column.  May be NULL */
   CollSeq *aColl[1];  /* Collating sequence for each term of the key */
 };
 
@@ -10115,7 +10408,7 @@
   int  nAlloc;         /* Amount of space allocated in zText */
   int  mxAlloc;        /* Maximum allowed string length */
   u8   mallocFailed;   /* Becomes true if any memory allocation fails */
-  u8   useMalloc;      /* True if zText is enlargeable using realloc */
+  u8   useMalloc;      /* 0: none,  1: sqlite3DbMalloc,  2: sqlite3_malloc */
   u8   tooBig;         /* Becomes true if string size exceeds limits */
 };
 
@@ -10291,7 +10584,7 @@
 SQLITE_PRIVATE void sqlite3PageFree(void*);
 SQLITE_PRIVATE void sqlite3MemSetDefault(void);
 SQLITE_PRIVATE void sqlite3BenignMallocHooks(void (*)(void), void (*)(void));
-SQLITE_PRIVATE int sqlite3MemoryAlarm(void (*)(void*, sqlite3_int64, int), void*, sqlite3_int64);
+SQLITE_PRIVATE int sqlite3HeapNearlyFull(void);
 
 /*
 ** On systems with ample stack space and that support alloca(), make
@@ -10413,7 +10706,7 @@
 #endif
 
 SQLITE_PRIVATE void sqlite3DropTable(Parse*, SrcList*, int, int);
-SQLITE_PRIVATE void sqlite3DeleteTable(Table*);
+SQLITE_PRIVATE void sqlite3DeleteTable(sqlite3*, Table*);
 #ifndef SQLITE_OMIT_AUTOINCREMENT
 SQLITE_PRIVATE   void sqlite3AutoincrementBegin(Parse *pParse);
 SQLITE_PRIVATE   void sqlite3AutoincrementEnd(Parse *pParse);
@@ -10462,7 +10755,6 @@
 SQLITE_PRIVATE void sqlite3ExprCacheRemove(Parse*, int, int);
 SQLITE_PRIVATE void sqlite3ExprCacheClear(Parse*);
 SQLITE_PRIVATE void sqlite3ExprCacheAffinityChange(Parse*, int, int);
-SQLITE_PRIVATE void sqlite3ExprHardCopy(Parse*,int,int);
 SQLITE_PRIVATE int sqlite3ExprCode(Parse*, Expr*, int);
 SQLITE_PRIVATE int sqlite3ExprCodeTemp(Parse*, Expr*, int*);
 SQLITE_PRIVATE int sqlite3ExprCodeTarget(Parse*, Expr*, int);
@@ -10582,8 +10874,6 @@
 #endif
 SQLITE_PRIVATE void sqlite3Attach(Parse*, Expr*, Expr*, Expr*);
 SQLITE_PRIVATE void sqlite3Detach(Parse*, Expr*);
-SQLITE_PRIVATE int sqlite3BtreeFactory(sqlite3 *db, const char *zFilename,
-                       int omitJournal, int nCache, int flags, Btree **ppBtree);
 SQLITE_PRIVATE int sqlite3FixInit(DbFixer*, Parse*, int, const char*, const Token*);
 SQLITE_PRIVATE int sqlite3FixSrcList(DbFixer*, SrcList*);
 SQLITE_PRIVATE int sqlite3FixSelect(DbFixer*, Select*);
@@ -10647,7 +10937,8 @@
 SQLITE_PRIVATE CollSeq *sqlite3FindCollSeq(sqlite3*,u8 enc, const char*,int);
 SQLITE_PRIVATE CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char*zName);
 SQLITE_PRIVATE CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr);
-SQLITE_PRIVATE Expr *sqlite3ExprSetColl(Parse *pParse, Expr *, Token *);
+SQLITE_PRIVATE Expr *sqlite3ExprSetColl(Expr*, CollSeq*);
+SQLITE_PRIVATE Expr *sqlite3ExprSetCollByToken(Parse *pParse, Expr*, Token*);
 SQLITE_PRIVATE int sqlite3CheckCollSeq(Parse *, CollSeq *);
 SQLITE_PRIVATE int sqlite3CheckObjectName(Parse *, const char *);
 SQLITE_PRIVATE void sqlite3VdbeSetChanges(sqlite3 *, int);
@@ -10668,6 +10959,7 @@
 SQLITE_PRIVATE const unsigned char sqlite3OpcodeProperty[];
 SQLITE_PRIVATE const unsigned char sqlite3UpperToLower[];
 SQLITE_PRIVATE const unsigned char sqlite3CtypeMap[];
+SQLITE_PRIVATE const Token sqlite3IntTokens[];
 SQLITE_PRIVATE SQLITE_WSD struct Sqlite3Config sqlite3Config;
 SQLITE_PRIVATE SQLITE_WSD FuncDefHash sqlite3GlobalFunctions;
 #ifndef SQLITE_OMIT_WSD
@@ -10696,7 +10988,7 @@
 SQLITE_PRIVATE int sqlite3FindDb(sqlite3*, Token*);
 SQLITE_PRIVATE int sqlite3FindDbName(sqlite3 *, const char *);
 SQLITE_PRIVATE int sqlite3AnalysisLoad(sqlite3*,int iDB);
-SQLITE_PRIVATE void sqlite3DeleteIndexSamples(Index*);
+SQLITE_PRIVATE void sqlite3DeleteIndexSamples(sqlite3*,Index*);
 SQLITE_PRIVATE void sqlite3DefaultRowEst(Index*);
 SQLITE_PRIVATE void sqlite3RegisterLikeFunctions(sqlite3*, int);
 SQLITE_PRIVATE int sqlite3IsLikeFunction(sqlite3*,Expr*,int*,char*);
@@ -10707,7 +10999,9 @@
 SQLITE_PRIVATE KeyInfo *sqlite3IndexKeyinfo(Parse *, Index *);
 SQLITE_PRIVATE int sqlite3CreateFunc(sqlite3 *, const char *, int, int, void *, 
   void (*)(sqlite3_context*,int,sqlite3_value **),
-  void (*)(sqlite3_context*,int,sqlite3_value **), void (*)(sqlite3_context*));
+  void (*)(sqlite3_context*,int,sqlite3_value **), void (*)(sqlite3_context*),
+  FuncDestructor *pDestructor
+);
 SQLITE_PRIVATE int sqlite3ApiExit(sqlite3 *db, int);
 SQLITE_PRIVATE int sqlite3OpenTempDatabase(Parse *);
 
@@ -10758,7 +11052,7 @@
 #  define sqlite3VtabUnlock(X)
 #  define sqlite3VtabUnlockList(X)
 #else
-SQLITE_PRIVATE    void sqlite3VtabClear(Table*);
+SQLITE_PRIVATE    void sqlite3VtabClear(sqlite3 *db, Table*);
 SQLITE_PRIVATE    int sqlite3VtabSync(sqlite3 *db, char **);
 SQLITE_PRIVATE    int sqlite3VtabRollback(sqlite3 *db);
 SQLITE_PRIVATE    int sqlite3VtabCommit(sqlite3 *db);
@@ -10811,9 +11105,9 @@
   #define sqlite3FkRequired(a,b,c,d) 0
 #endif
 #ifndef SQLITE_OMIT_FOREIGN_KEY
-SQLITE_PRIVATE   void sqlite3FkDelete(Table*);
+SQLITE_PRIVATE   void sqlite3FkDelete(sqlite3 *, Table*);
 #else
-  #define sqlite3FkDelete(a)
+  #define sqlite3FkDelete(a,b)
 #endif
 
 
@@ -10906,17 +11200,18 @@
 ** sqlite3MemdebugHasType() returns true if any of the bits in its second
 ** argument match the type set by the previous sqlite3MemdebugSetType().
 ** sqlite3MemdebugHasType() is intended for use inside assert() statements.
-** For example:
 **
-**     assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
+** sqlite3MemdebugNoType() returns true if none of the bits in its second
+** argument match the type set by the previous sqlite3MemdebugSetType().
 **
 ** Perhaps the most important point is the difference between MEMTYPE_HEAP
-** and MEMTYPE_DB.  If an allocation is MEMTYPE_DB, that means it might have
-** been allocated by lookaside, except the allocation was too large or
-** lookaside was already full.  It is important to verify that allocations
-** that might have been satisfied by lookaside are not passed back to 
-** non-lookaside free() routines.  Asserts such as the example above are
-** placed on the non-lookaside free() routines to verify this constraint. 
+** and MEMTYPE_LOOKASIDE.  If an allocation is MEMTYPE_LOOKASIDE, that means
+** it might have been allocated by lookaside, except the allocation was
+** too large or lookaside was already full.  It is important to verify
+** that allocations that might have been satisfied by lookaside are not
+** passed back to non-lookaside free() routines.  Asserts such as the
+** example above are placed on the non-lookaside free() routines to verify
+** this constraint. 
 **
 ** All of this is no-op for a production build.  It only comes into
 ** play when the SQLITE_MEMDEBUG compile-time option is used.
@@ -10924,14 +11219,17 @@
 #ifdef SQLITE_MEMDEBUG
 SQLITE_PRIVATE   void sqlite3MemdebugSetType(void*,u8);
 SQLITE_PRIVATE   int sqlite3MemdebugHasType(void*,u8);
+SQLITE_PRIVATE   int sqlite3MemdebugNoType(void*,u8);
 #else
 # define sqlite3MemdebugSetType(X,Y)  /* no-op */
 # define sqlite3MemdebugHasType(X,Y)  1
+# define sqlite3MemdebugNoType(X,Y)   1
 #endif
-#define MEMTYPE_HEAP     0x01    /* General heap allocations */
-#define MEMTYPE_DB       0x02    /* Associated with a database connection */
-#define MEMTYPE_SCRATCH  0x04    /* Scratch allocations */
-#define MEMTYPE_PCACHE   0x08    /* Page cache allocations */
+#define MEMTYPE_HEAP       0x01  /* General heap allocations */
+#define MEMTYPE_LOOKASIDE  0x02  /* Might have been lookaside memory */
+#define MEMTYPE_SCRATCH    0x04  /* Scratch allocations */
+#define MEMTYPE_PCACHE     0x08  /* Page cache allocations */
+#define MEMTYPE_DB         0x10  /* Uses sqlite3DbMalloc, not sqlite_malloc */
 
 #endif /* _SQLITEINT_H_ */
 
@@ -11115,6 +11413,15 @@
 SQLITE_PRIVATE SQLITE_WSD FuncDefHash sqlite3GlobalFunctions;
 
 /*
+** Constant tokens for values 0 and 1.
+*/
+SQLITE_PRIVATE const Token sqlite3IntTokens[] = {
+   { "0", 1 },
+   { "1", 1 }
+};
+
+
+/*
 ** The value of the "pending" byte must be 0x40000000 (1 byte past the
 ** 1-gibabyte boundary) in a compatible database.  SQLite never uses
 ** the database page that contains the pending byte.  It never attempts
@@ -11553,14 +11860,454 @@
 ** This module implements the sqlite3_status() interface and related
 ** functionality.
 */
+/************** Include vdbeInt.h in the middle of status.c ******************/
+/************** Begin file vdbeInt.h *****************************************/
+/*
+** 2003 September 6
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This is the header file for information that is private to the
+** VDBE.  This information used to all be at the top of the single
+** source code file "vdbe.c".  When that file became too big (over
+** 6000 lines long) it was split up into several smaller files and
+** this header information was factored out.
+*/
+#ifndef _VDBEINT_H_
+#define _VDBEINT_H_
+
+/*
+** SQL is translated into a sequence of instructions to be
+** executed by a virtual machine.  Each instruction is an instance
+** of the following structure.
+*/
+typedef struct VdbeOp Op;
+
+/*
+** Boolean values
+*/
+typedef unsigned char Bool;
+
+/*
+** A cursor is a pointer into a single BTree within a database file.
+** The cursor can seek to a BTree entry with a particular key, or
+** loop over all entries of the Btree.  You can also insert new BTree
+** entries or retrieve the key or data from the entry that the cursor
+** is currently pointing to.
+** 
+** Every cursor that the virtual machine has open is represented by an
+** instance of the following structure.
+**
+** If the VdbeCursor.isTriggerRow flag is set it means that this cursor is
+** really a single row that represents the NEW or OLD pseudo-table of
+** a row trigger.  The data for the row is stored in VdbeCursor.pData and
+** the rowid is in VdbeCursor.iKey.
+*/
+struct VdbeCursor {
+  BtCursor *pCursor;    /* The cursor structure of the backend */
+  int iDb;              /* Index of cursor database in db->aDb[] (or -1) */
+  i64 lastRowid;        /* Last rowid from a Next or NextIdx operation */
+  Bool zeroed;          /* True if zeroed out and ready for reuse */
+  Bool rowidIsValid;    /* True if lastRowid is valid */
+  Bool atFirst;         /* True if pointing to first entry */
+  Bool useRandomRowid;  /* Generate new record numbers semi-randomly */
+  Bool nullRow;         /* True if pointing to a row with no data */
+  Bool deferredMoveto;  /* A call to sqlite3BtreeMoveto() is needed */
+  Bool isTable;         /* True if a table requiring integer keys */
+  Bool isIndex;         /* True if an index containing keys only - no data */
+  Bool isOrdered;       /* True if the underlying table is BTREE_UNORDERED */
+  i64 movetoTarget;     /* Argument to the deferred sqlite3BtreeMoveto() */
+  Btree *pBt;           /* Separate file holding temporary table */
+  int pseudoTableReg;   /* Register holding pseudotable content. */
+  KeyInfo *pKeyInfo;    /* Info about index keys needed by index cursors */
+  int nField;           /* Number of fields in the header */
+  i64 seqCount;         /* Sequence counter */
+  sqlite3_vtab_cursor *pVtabCursor;  /* The cursor for a virtual table */
+  const sqlite3_module *pModule;     /* Module for cursor pVtabCursor */
+
+  /* Result of last sqlite3BtreeMoveto() done by an OP_NotExists or 
+  ** OP_IsUnique opcode on this cursor. */
+  int seekResult;
+
+  /* Cached information about the header for the data record that the
+  ** cursor is currently pointing to.  Only valid if cacheStatus matches
+  ** Vdbe.cacheCtr.  Vdbe.cacheCtr will never take on the value of
+  ** CACHE_STALE and so setting cacheStatus=CACHE_STALE guarantees that
+  ** the cache is out of date.
+  **
+  ** aRow might point to (ephemeral) data for the current row, or it might
+  ** be NULL.
+  */
+  u32 cacheStatus;      /* Cache is valid if this matches Vdbe.cacheCtr */
+  int payloadSize;      /* Total number of bytes in the record */
+  u32 *aType;           /* Type values for all entries in the record */
+  u32 *aOffset;         /* Cached offsets to the start of each columns data */
+  u8 *aRow;             /* Data for the current row, if all on one page */
+};
+typedef struct VdbeCursor VdbeCursor;
+
+/*
+** When a sub-program is executed (OP_Program), a structure of this type
+** is allocated to store the current value of the program counter, as
+** well as the current memory cell array and various other frame specific
+** values stored in the Vdbe struct. When the sub-program is finished, 
+** these values are copied back to the Vdbe from the VdbeFrame structure,
+** restoring the state of the VM to as it was before the sub-program
+** began executing.
+**
+** Frames are stored in a linked list headed at Vdbe.pParent. Vdbe.pParent
+** is the parent of the current frame, or zero if the current frame
+** is the main Vdbe program.
+*/
+typedef struct VdbeFrame VdbeFrame;
+struct VdbeFrame {
+  Vdbe *v;                /* VM this frame belongs to */
+  int pc;                 /* Program Counter */
+  Op *aOp;                /* Program instructions */
+  int nOp;                /* Size of aOp array */
+  Mem *aMem;              /* Array of memory cells */
+  int nMem;               /* Number of entries in aMem */
+  VdbeCursor **apCsr;     /* Element of Vdbe cursors */
+  u16 nCursor;            /* Number of entries in apCsr */
+  void *token;            /* Copy of SubProgram.token */
+  int nChildMem;          /* Number of memory cells for child frame */
+  int nChildCsr;          /* Number of cursors for child frame */
+  i64 lastRowid;          /* Last insert rowid (sqlite3.lastRowid) */
+  int nChange;            /* Statement changes (Vdbe.nChanges)     */
+  VdbeFrame *pParent;     /* Parent of this frame */
+};
+
+#define VdbeFrameMem(p) ((Mem *)&((u8 *)p)[ROUND8(sizeof(VdbeFrame))])
+
+/*
+** A value for VdbeCursor.cacheValid that means the cache is always invalid.
+*/
+#define CACHE_STALE 0
+
+/*
+** Internally, the vdbe manipulates nearly all SQL values as Mem
+** structures. Each Mem struct may cache multiple representations (string,
+** integer etc.) of the same value.  A value (and therefore Mem structure)
+** has the following properties:
+**
+** Each value has a manifest type. The manifest type of the value stored
+** in a Mem struct is returned by the MemType(Mem*) macro. The type is
+** one of SQLITE_NULL, SQLITE_INTEGER, SQLITE_REAL, SQLITE_TEXT or
+** SQLITE_BLOB.
+*/
+struct Mem {
+  union {
+    i64 i;              /* Integer value. */
+    int nZero;          /* Used when bit MEM_Zero is set in flags */
+    FuncDef *pDef;      /* Used only when flags==MEM_Agg */
+    RowSet *pRowSet;    /* Used only when flags==MEM_RowSet */
+    VdbeFrame *pFrame;  /* Used when flags==MEM_Frame */
+  } u;
+  double r;           /* Real value */
+  sqlite3 *db;        /* The associated database connection */
+  char *z;            /* String or BLOB value */
+  int n;              /* Number of characters in string value, excluding '\0' */
+  u16 flags;          /* Some combination of MEM_Null, MEM_Str, MEM_Dyn, etc. */
+  u8  type;           /* One of SQLITE_NULL, SQLITE_TEXT, SQLITE_INTEGER, etc */
+  u8  enc;            /* SQLITE_UTF8, SQLITE_UTF16BE, SQLITE_UTF16LE */
+#ifdef SQLITE_DEBUG
+  Mem *pScopyFrom;    /* This Mem is a shallow copy of pScopyFrom */
+  void *pFiller;      /* So that sizeof(Mem) is a multiple of 8 */
+#endif
+  void (*xDel)(void *);  /* If not null, call this function to delete Mem.z */
+  char *zMalloc;      /* Dynamic buffer allocated by sqlite3_malloc() */
+};
+
+/* One or more of the following flags are set to indicate the validOK
+** representations of the value stored in the Mem struct.
+**
+** If the MEM_Null flag is set, then the value is an SQL NULL value.
+** No other flags may be set in this case.
+**
+** If the MEM_Str flag is set then Mem.z points at a string representation.
+** Usually this is encoded in the same unicode encoding as the main
+** database (see below for exceptions). If the MEM_Term flag is also
+** set, then the string is nul terminated. The MEM_Int and MEM_Real 
+** flags may coexist with the MEM_Str flag.
+**
+** Multiple of these values can appear in Mem.flags.  But only one
+** at a time can appear in Mem.type.
+*/
+#define MEM_Null      0x0001   /* Value is NULL */
+#define MEM_Str       0x0002   /* Value is a string */
+#define MEM_Int       0x0004   /* Value is an integer */
+#define MEM_Real      0x0008   /* Value is a real number */
+#define MEM_Blob      0x0010   /* Value is a BLOB */
+#define MEM_RowSet    0x0020   /* Value is a RowSet object */
+#define MEM_Frame     0x0040   /* Value is a VdbeFrame object */
+#define MEM_Invalid   0x0080   /* Value is undefined */
+#define MEM_TypeMask  0x00ff   /* Mask of type bits */
+
+/* Whenever Mem contains a valid string or blob representation, one of
+** the following flags must be set to determine the memory management
+** policy for Mem.z.  The MEM_Term flag tells us whether or not the
+** string is \000 or \u0000 terminated
+*/
+#define MEM_Term      0x0200   /* String rep is nul terminated */
+#define MEM_Dyn       0x0400   /* Need to call sqliteFree() on Mem.z */
+#define MEM_Static    0x0800   /* Mem.z points to a static string */
+#define MEM_Ephem     0x1000   /* Mem.z points to an ephemeral string */
+#define MEM_Agg       0x2000   /* Mem.z points to an agg function context */
+#define MEM_Zero      0x4000   /* Mem.i contains count of 0s appended to blob */
+#ifdef SQLITE_OMIT_INCRBLOB
+  #undef MEM_Zero
+  #define MEM_Zero 0x0000
+#endif
+
+/*
+** Clear any existing type flags from a Mem and replace them with f
+*/
+#define MemSetTypeFlag(p, f) \
+   ((p)->flags = ((p)->flags&~(MEM_TypeMask|MEM_Zero))|f)
+
+/*
+** Return true if a memory cell is not marked as invalid.  This macro
+** is for use inside assert() statements only.
+*/
+#ifdef SQLITE_DEBUG
+#define memIsValid(M)  ((M)->flags & MEM_Invalid)==0
+#endif
+
+
+/* A VdbeFunc is just a FuncDef (defined in sqliteInt.h) that contains
+** additional information about auxiliary information bound to arguments
+** of the function.  This is used to implement the sqlite3_get_auxdata()
+** and sqlite3_set_auxdata() APIs.  The "auxdata" is some auxiliary data
+** that can be associated with a constant argument to a function.  This
+** allows functions such as "regexp" to compile their constant regular
+** expression argument once and reused the compiled code for multiple
+** invocations.
+*/
+struct VdbeFunc {
+  FuncDef *pFunc;               /* The definition of the function */
+  int nAux;                     /* Number of entries allocated for apAux[] */
+  struct AuxData {
+    void *pAux;                   /* Aux data for the i-th argument */
+    void (*xDelete)(void *);      /* Destructor for the aux data */
+  } apAux[1];                   /* One slot for each function argument */
+};
+
+/*
+** The "context" argument for a installable function.  A pointer to an
+** instance of this structure is the first argument to the routines used
+** implement the SQL functions.
+**
+** There is a typedef for this structure in sqlite.h.  So all routines,
+** even the public interface to SQLite, can use a pointer to this structure.
+** But this file is the only place where the internal details of this
+** structure are known.
+**
+** This structure is defined inside of vdbeInt.h because it uses substructures
+** (Mem) which are only defined there.
+*/
+struct sqlite3_context {
+  FuncDef *pFunc;       /* Pointer to function information.  MUST BE FIRST */
+  VdbeFunc *pVdbeFunc;  /* Auxilary data, if created. */
+  Mem s;                /* The return value is stored here */
+  Mem *pMem;            /* Memory cell used to store aggregate context */
+  int isError;          /* Error code returned by the function. */
+  CollSeq *pColl;       /* Collating sequence */
+};
+
+/*
+** A Set structure is used for quick testing to see if a value
+** is part of a small set.  Sets are used to implement code like
+** this:
+**            x.y IN ('hi','hoo','hum')
+*/
+typedef struct Set Set;
+struct Set {
+  Hash hash;             /* A set is just a hash table */
+  HashElem *prev;        /* Previously accessed hash elemen */
+};
+
+/*
+** An instance of the virtual machine.  This structure contains the complete
+** state of the virtual machine.
+**
+** The "sqlite3_stmt" structure pointer that is returned by sqlite3_compile()
+** is really a pointer to an instance of this structure.
+**
+** The Vdbe.inVtabMethod variable is set to non-zero for the duration of
+** any virtual table method invocations made by the vdbe program. It is
+** set to 2 for xDestroy method calls and 1 for all other methods. This
+** variable is used for two purposes: to allow xDestroy methods to execute
+** "DROP TABLE" statements and to prevent some nasty side effects of
+** malloc failure when SQLite is invoked recursively by a virtual table 
+** method function.
+*/
+struct Vdbe {
+  sqlite3 *db;            /* The database connection that owns this statement */
+  Vdbe *pPrev,*pNext;     /* Linked list of VDBEs with the same Vdbe.db */
+  int nOp;                /* Number of instructions in the program */
+  int nOpAlloc;           /* Number of slots allocated for aOp[] */
+  Op *aOp;                /* Space to hold the virtual machine's program */
+  int nLabel;             /* Number of labels used */
+  int nLabelAlloc;        /* Number of slots allocated in aLabel[] */
+  int *aLabel;            /* Space to hold the labels */
+  Mem **apArg;            /* Arguments to currently executing user function */
+  Mem *aColName;          /* Column names to return */
+  Mem *pResultSet;        /* Pointer to an array of results */
+  u16 nResColumn;         /* Number of columns in one row of the result set */
+  u16 nCursor;            /* Number of slots in apCsr[] */
+  VdbeCursor **apCsr;     /* One element of this array for each open cursor */
+  u8 errorAction;         /* Recovery action to do in case of an error */
+  u8 okVar;               /* True if azVar[] has been initialized */
+  ynVar nVar;             /* Number of entries in aVar[] */
+  Mem *aVar;              /* Values for the OP_Variable opcode. */
+  char **azVar;           /* Name of variables */
+  u32 magic;              /* Magic number for sanity checking */
+  int nMem;               /* Number of memory locations currently allocated */
+  Mem *aMem;              /* The memory locations */
+  u32 cacheCtr;           /* VdbeCursor row cache generation counter */
+  int pc;                 /* The program counter */
+  int rc;                 /* Value to return */
+  char *zErrMsg;          /* Error message written here */
+  u8 explain;             /* True if EXPLAIN present on SQL command */
+  u8 changeCntOn;         /* True to update the change-counter */
+  u8 expired;             /* True if the VM needs to be recompiled */
+  u8 runOnlyOnce;         /* Automatically expire on reset */
+  u8 minWriteFileFormat;  /* Minimum file format for writable database files */
+  u8 inVtabMethod;        /* See comments above */
+  u8 usesStmtJournal;     /* True if uses a statement journal */
+  u8 readOnly;            /* True for read-only statements */
+  u8 isPrepareV2;         /* True if prepared with prepare_v2() */
+  int nChange;            /* Number of db changes made since last reset */
+  int btreeMask;          /* Bitmask of db->aDb[] entries referenced */
+  i64 startTime;          /* Time when query started - used for profiling */
+  BtreeMutexArray aMutex; /* An array of Btree used here and needing locks */
+  int aCounter[3];        /* Counters used by sqlite3_stmt_status() */
+  char *zSql;             /* Text of the SQL statement that generated this */
+  void *pFree;            /* Free this when deleting the vdbe */
+  i64 nFkConstraint;      /* Number of imm. FK constraints this VM */
+  i64 nStmtDefCons;       /* Number of def. constraints when stmt started */
+  int iStatement;         /* Statement number (or 0 if has not opened stmt) */
+#ifdef SQLITE_DEBUG
+  FILE *trace;            /* Write an execution trace here, if not NULL */
+#endif
+  VdbeFrame *pFrame;      /* Parent frame */
+  int nFrame;             /* Number of frames in pFrame list */
+  u32 expmask;            /* Binding to these vars invalidates VM */
+  SubProgram *pProgram;   /* Linked list of all sub-programs used by VM */
+};
+
+/*
+** The following are allowed values for Vdbe.magic
+*/
+#define VDBE_MAGIC_INIT     0x26bceaa5    /* Building a VDBE program */
+#define VDBE_MAGIC_RUN      0xbdf20da3    /* VDBE is ready to execute */
+#define VDBE_MAGIC_HALT     0x519c2973    /* VDBE has completed execution */
+#define VDBE_MAGIC_DEAD     0xb606c3c8    /* The VDBE has been deallocated */
+
+/*
+** Function prototypes
+*/
+SQLITE_PRIVATE void sqlite3VdbeFreeCursor(Vdbe *, VdbeCursor*);
+void sqliteVdbePopStack(Vdbe*,int);
+SQLITE_PRIVATE int sqlite3VdbeCursorMoveto(VdbeCursor*);
+#if defined(SQLITE_DEBUG) || defined(VDBE_PROFILE)
+SQLITE_PRIVATE void sqlite3VdbePrintOp(FILE*, int, Op*);
+#endif
+SQLITE_PRIVATE u32 sqlite3VdbeSerialTypeLen(u32);
+SQLITE_PRIVATE u32 sqlite3VdbeSerialType(Mem*, int);
+SQLITE_PRIVATE u32 sqlite3VdbeSerialPut(unsigned char*, int, Mem*, int);
+SQLITE_PRIVATE u32 sqlite3VdbeSerialGet(const unsigned char*, u32, Mem*);
+SQLITE_PRIVATE void sqlite3VdbeDeleteAuxData(VdbeFunc*, int);
+
+int sqlite2BtreeKeyCompare(BtCursor *, const void *, int, int, int *);
+SQLITE_PRIVATE int sqlite3VdbeIdxKeyCompare(VdbeCursor*,UnpackedRecord*,int*);
+SQLITE_PRIVATE int sqlite3VdbeIdxRowid(sqlite3*, BtCursor *, i64 *);
+SQLITE_PRIVATE int sqlite3MemCompare(const Mem*, const Mem*, const CollSeq*);
+SQLITE_PRIVATE int sqlite3VdbeExec(Vdbe*);
+SQLITE_PRIVATE int sqlite3VdbeList(Vdbe*);
+SQLITE_PRIVATE int sqlite3VdbeHalt(Vdbe*);
+SQLITE_PRIVATE int sqlite3VdbeChangeEncoding(Mem *, int);
+SQLITE_PRIVATE int sqlite3VdbeMemTooBig(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemCopy(Mem*, const Mem*);
+SQLITE_PRIVATE void sqlite3VdbeMemShallowCopy(Mem*, const Mem*, int);
+SQLITE_PRIVATE void sqlite3VdbeMemMove(Mem*, Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemNulTerminate(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemSetStr(Mem*, const char*, int, u8, void(*)(void*));
+SQLITE_PRIVATE void sqlite3VdbeMemSetInt64(Mem*, i64);
+#ifdef SQLITE_OMIT_FLOATING_POINT
+# define sqlite3VdbeMemSetDouble sqlite3VdbeMemSetInt64
+#else
+SQLITE_PRIVATE   void sqlite3VdbeMemSetDouble(Mem*, double);
+#endif
+SQLITE_PRIVATE void sqlite3VdbeMemSetNull(Mem*);
+SQLITE_PRIVATE void sqlite3VdbeMemSetZeroBlob(Mem*,int);
+SQLITE_PRIVATE void sqlite3VdbeMemSetRowSet(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemMakeWriteable(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemStringify(Mem*, int);
+SQLITE_PRIVATE i64 sqlite3VdbeIntValue(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemIntegerify(Mem*);
+SQLITE_PRIVATE double sqlite3VdbeRealValue(Mem*);
+SQLITE_PRIVATE void sqlite3VdbeIntegerAffinity(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemRealify(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemNumerify(Mem*);
+SQLITE_PRIVATE int sqlite3VdbeMemFromBtree(BtCursor*,int,int,int,Mem*);
+SQLITE_PRIVATE void sqlite3VdbeMemRelease(Mem *p);
+SQLITE_PRIVATE void sqlite3VdbeMemReleaseExternal(Mem *p);
+SQLITE_PRIVATE int sqlite3VdbeMemFinalize(Mem*, FuncDef*);
+SQLITE_PRIVATE const char *sqlite3OpcodeName(int);
+SQLITE_PRIVATE int sqlite3VdbeMemGrow(Mem *pMem, int n, int preserve);
+SQLITE_PRIVATE int sqlite3VdbeCloseStatement(Vdbe *, int);
+SQLITE_PRIVATE void sqlite3VdbeFrameDelete(VdbeFrame*);
+SQLITE_PRIVATE int sqlite3VdbeFrameRestore(VdbeFrame *);
+SQLITE_PRIVATE void sqlite3VdbeMemStoreType(Mem *pMem);
+
+#ifdef SQLITE_DEBUG
+SQLITE_PRIVATE void sqlite3VdbeMemPrepareToChange(Vdbe*,Mem*);
+#endif
+
+#ifndef SQLITE_OMIT_FOREIGN_KEY
+SQLITE_PRIVATE int sqlite3VdbeCheckFk(Vdbe *, int);
+#else
+# define sqlite3VdbeCheckFk(p,i) 0
+#endif
+
+#ifndef SQLITE_OMIT_SHARED_CACHE
+SQLITE_PRIVATE void sqlite3VdbeMutexArrayEnter(Vdbe *p);
+#else
+# define sqlite3VdbeMutexArrayEnter(p)
+#endif
+
+SQLITE_PRIVATE int sqlite3VdbeMemTranslate(Mem*, u8);
+#ifdef SQLITE_DEBUG
+SQLITE_PRIVATE   void sqlite3VdbePrintSql(Vdbe*);
+SQLITE_PRIVATE   void sqlite3VdbeMemPrettyPrint(Mem *pMem, char *zBuf);
+#endif
+SQLITE_PRIVATE int sqlite3VdbeMemHandleBom(Mem *pMem);
+
+#ifndef SQLITE_OMIT_INCRBLOB
+SQLITE_PRIVATE   int sqlite3VdbeMemExpandBlob(Mem *);
+#else
+  #define sqlite3VdbeMemExpandBlob(x) SQLITE_OK
+#endif
+
+#endif /* !defined(_VDBEINT_H_) */
+
+/************** End of vdbeInt.h *********************************************/
+/************** Continuing where we left off in status.c *********************/
 
 /*
 ** Variables in which to record status information.
 */
 typedef struct sqlite3StatType sqlite3StatType;
 static SQLITE_WSD struct sqlite3StatType {
-  int nowValue[9];         /* Current value */
-  int mxValue[9];          /* Maximum value */
+  int nowValue[10];         /* Current value */
+  int mxValue[10];          /* Maximum value */
 } sqlite3Stat = { {0,}, {0,} };
 
 
@@ -11642,6 +12389,8 @@
   int *pHighwater,      /* Write high-water mark here */
   int resetFlag         /* Reset high-water mark if true */
 ){
+  int rc = SQLITE_OK;   /* Return code */
+  sqlite3_mutex_enter(db->mutex);
   switch( op ){
     case SQLITE_DBSTATUS_LOOKASIDE_USED: {
       *pCurrent = db->lookaside.nOut;
@@ -11660,6 +12409,7 @@
     case SQLITE_DBSTATUS_CACHE_USED: {
       int totalUsed = 0;
       int i;
+      sqlite3BtreeEnterAll(db);
       for(i=0; i<db->nDb; i++){
         Btree *pBt = db->aDb[i].pBt;
         if( pBt ){
@@ -11667,15 +12417,80 @@
           totalUsed += sqlite3PagerMemUsed(pPager);
         }
       }
+      sqlite3BtreeLeaveAll(db);
       *pCurrent = totalUsed;
       *pHighwater = 0;
       break;
     }
+
+    /*
+    ** *pCurrent gets an accurate estimate of the amount of memory used
+    ** to store the schema for all databases (main, temp, and any ATTACHed
+    ** databases.  *pHighwater is set to zero.
+    */
+    case SQLITE_DBSTATUS_SCHEMA_USED: {
+      int i;                      /* Used to iterate through schemas */
+      int nByte = 0;              /* Used to accumulate return value */
+
+      db->pnBytesFreed = &nByte;
+      for(i=0; i<db->nDb; i++){
+        Schema *pSchema = db->aDb[i].pSchema;
+        if( ALWAYS(pSchema!=0) ){
+          HashElem *p;
+
+          nByte += sqlite3GlobalConfig.m.xRoundup(sizeof(HashElem)) * (
+              pSchema->tblHash.count 
+            + pSchema->trigHash.count
+            + pSchema->idxHash.count
+            + pSchema->fkeyHash.count
+          );
+          nByte += sqlite3MallocSize(pSchema->tblHash.ht);
+          nByte += sqlite3MallocSize(pSchema->trigHash.ht);
+          nByte += sqlite3MallocSize(pSchema->idxHash.ht);
+          nByte += sqlite3MallocSize(pSchema->fkeyHash.ht);
+
+          for(p=sqliteHashFirst(&pSchema->trigHash); p; p=sqliteHashNext(p)){
+            sqlite3DeleteTrigger(db, (Trigger*)sqliteHashData(p));
+          }
+          for(p=sqliteHashFirst(&pSchema->tblHash); p; p=sqliteHashNext(p)){
+            sqlite3DeleteTable(db, (Table *)sqliteHashData(p));
+          }
+        }
+      }
+      db->pnBytesFreed = 0;
+
+      *pHighwater = 0;
+      *pCurrent = nByte;
+      break;
+    }
+
+    /*
+    ** *pCurrent gets an accurate estimate of the amount of memory used
+    ** to store all prepared statements.
+    ** *pHighwater is set to zero.
+    */
+    case SQLITE_DBSTATUS_STMT_USED: {
+      struct Vdbe *pVdbe;         /* Used to iterate through VMs */
+      int nByte = 0;              /* Used to accumulate return value */
+
+      db->pnBytesFreed = &nByte;
+      for(pVdbe=db->pVdbe; pVdbe; pVdbe=pVdbe->pNext){
+        sqlite3VdbeDeleteObject(db, pVdbe);
+      }
+      db->pnBytesFreed = 0;
+
+      *pHighwater = 0;
+      *pCurrent = nByte;
+
+      break;
+    }
+
     default: {
-      return SQLITE_ERROR;
+      rc = SQLITE_ERROR;
     }
   }
-  return SQLITE_OK;
+  sqlite3_mutex_leave(db->mutex);
+  return rc;
 }
 
 /************** End of status.c **********************************************/
@@ -12878,26 +13693,23 @@
 SQLITE_PRIVATE int sqlite3OsDeviceCharacteristics(sqlite3_file *id){
   return id->pMethods->xDeviceCharacteristics(id);
 }
-SQLITE_PRIVATE int sqlite3OsShmOpen(sqlite3_file *id){
-  return id->pMethods->xShmOpen(id);
-}
 SQLITE_PRIVATE int sqlite3OsShmLock(sqlite3_file *id, int offset, int n, int flags){
   return id->pMethods->xShmLock(id, offset, n, flags);
 }
 SQLITE_PRIVATE void sqlite3OsShmBarrier(sqlite3_file *id){
   id->pMethods->xShmBarrier(id);
 }
-SQLITE_PRIVATE int sqlite3OsShmClose(sqlite3_file *id, int deleteFlag){
-  return id->pMethods->xShmClose(id, deleteFlag);
+SQLITE_PRIVATE int sqlite3OsShmUnmap(sqlite3_file *id, int deleteFlag){
+  return id->pMethods->xShmUnmap(id, deleteFlag);
 }
 SQLITE_PRIVATE int sqlite3OsShmMap(
-  sqlite3_file *id, 
-  int iPage, 
-  int pgsz, 
-  int isWrite, 
-  void volatile **pp
+  sqlite3_file *id,               /* Database file handle */
+  int iPage,
+  int pgsz,
+  int bExtend,                    /* True to extend file if necessary */
+  void volatile **pp              /* OUT: Pointer to mapping */
 ){
-  return id->pMethods->xShmMap(id, iPage, pgsz, isWrite, pp);
+  return id->pMethods->xShmMap(id, iPage, pgsz, bExtend, pp);
 }
 
 /*
@@ -12913,11 +13725,11 @@
 ){
   int rc;
   DO_OS_MALLOC_TEST(0);
-  /* 0x7f3f is a mask of SQLITE_OPEN_ flags that are valid to be passed
+  /* 0x87f3f is a mask of SQLITE_OPEN_ flags that are valid to be passed
   ** down into the VFS layer.  Some SQLITE_OPEN_ flags (for example,
   ** SQLITE_OPEN_FULLMUTEX or SQLITE_OPEN_SHAREDCACHE) are blocked before
   ** reaching the VFS. */
-  rc = pVfs->xOpen(pVfs, zPath, pFile, flags & 0x7f3f, pFlagsOut);
+  rc = pVfs->xOpen(pVfs, zPath, pFile, flags & 0x87f3f, pFlagsOut);
   assert( rc==SQLITE_OK || pFile->pMethods==0 );
   return rc;
 }
@@ -12964,6 +13776,12 @@
 }
 SQLITE_PRIVATE int sqlite3OsCurrentTimeInt64(sqlite3_vfs *pVfs, sqlite3_int64 *pTimeOut){
   int rc;
+  /* IMPLEMENTATION-OF: R-49045-42493 SQLite will use the xCurrentTimeInt64()
+  ** method to get the current date and time if that method is available
+  ** (if iVersion is 2 or greater and the function pointer is not NULL) and
+  ** will fall back to xCurrentTime() if xCurrentTimeInt64() is
+  ** unavailable.
+  */
   if( pVfs->iVersion>=2 && pVfs->xCurrentTimeInt64 ){
     rc = pVfs->xCurrentTimeInt64(pVfs, pTimeOut);
   }else{
@@ -13347,7 +14165,7 @@
 static void *sqlite3MemRealloc(void *pPrior, int nByte){
   sqlite3_int64 *p = (sqlite3_int64*)pPrior;
   assert( pPrior!=0 && nByte>0 );
-  nByte = ROUND8(nByte);
+  assert( nByte==ROUND8(nByte) ); /* EV: R-46199-30249 */
   p--;
   p = realloc(p, nByte+8 );
   if( p ){
@@ -13753,6 +14571,7 @@
   struct MemBlockHdr *pOldHdr;
   void *pNew;
   assert( mem.disallow==0 );
+  assert( (nByte & 7)==0 );     /* EV: R-46199-30249 */
   pOldHdr = sqlite3MemsysGetHeader(pPrior);
   pNew = sqlite3MemMalloc(nByte);
   if( pNew ){
@@ -13787,7 +14606,7 @@
 ** Set the "type" of an allocation.
 */
 SQLITE_PRIVATE void sqlite3MemdebugSetType(void *p, u8 eType){
-  if( p ){
+  if( p && sqlite3GlobalConfig.m.xMalloc==sqlite3MemMalloc ){
     struct MemBlockHdr *pHdr;
     pHdr = sqlite3MemsysGetHeader(p);
     assert( pHdr->iForeGuard==FOREGUARD );
@@ -13806,23 +14625,38 @@
 */
 SQLITE_PRIVATE int sqlite3MemdebugHasType(void *p, u8 eType){
   int rc = 1;
-  if( p ){
+  if( p && sqlite3GlobalConfig.m.xMalloc==sqlite3MemMalloc ){
     struct MemBlockHdr *pHdr;
     pHdr = sqlite3MemsysGetHeader(p);
     assert( pHdr->iForeGuard==FOREGUARD );         /* Allocation is valid */
-    assert( (pHdr->eType & (pHdr->eType-1))==0 );  /* Only one type bit set */
     if( (pHdr->eType&eType)==0 ){
-      void **pBt;
-      pBt = (void**)pHdr;
-      pBt -= pHdr->nBacktraceSlots;
-      backtrace_symbols_fd(pBt, pHdr->nBacktrace, fileno(stderr));
-      fprintf(stderr, "\n");
       rc = 0;
     }
   }
   return rc;
 }
- 
+
+/*
+** Return TRUE if the mask of type in eType matches no bits of the type of the
+** allocation p.  Also return true if p==NULL.
+**
+** This routine is designed for use within an assert() statement, to
+** verify the type of an allocation.  For example:
+**
+**     assert( sqlite3MemdebugNoType(p, MEMTYPE_DB) );
+*/
+SQLITE_PRIVATE int sqlite3MemdebugNoType(void *p, u8 eType){
+  int rc = 1;
+  if( p && sqlite3GlobalConfig.m.xMalloc==sqlite3MemMalloc ){
+    struct MemBlockHdr *pHdr;
+    pHdr = sqlite3MemsysGetHeader(p);
+    assert( pHdr->iForeGuard==FOREGUARD );         /* Allocation is valid */
+    if( (pHdr->eType&eType)!=0 ){
+      rc = 0;
+    }
+  }
+  return rc;
+}
 
 /*
 ** Set the number of backtrace levels kept for each allocation.
@@ -15007,7 +15841,7 @@
   int nOld;
   void *p;
   assert( pPrior!=0 );
-  assert( (nBytes&(nBytes-1))==0 );
+  assert( (nBytes&(nBytes-1))==0 );  /* EV: R-46199-30249 */
   assert( nBytes>=0 );
   if( nBytes==0 ){
     return 0;
@@ -16065,6 +16899,7 @@
   */
   pthread_mutex_lock(&p->mutex);
 #if SQLITE_MUTEX_NREF
+  assert( p->nRef>0 || p->owner==0 );
   p->owner = pthread_self();
   p->nRef++;
 #endif
@@ -16137,6 +16972,7 @@
   assert( pthreadMutexHeld(p) );
 #if SQLITE_MUTEX_NREF
   p->nRef--;
+  if( p->nRef==0 ) p->owner = 0;
 #endif
   assert( p->nRef==0 || p->id==SQLITE_MUTEX_RECURSIVE );
 
@@ -16401,7 +17237,7 @@
 */
 static void winMutexFree(sqlite3_mutex *p){
   assert( p );
-  assert( p->nRef==0 );
+  assert( p->nRef==0 && p->owner==0 );
   assert( p->id==SQLITE_MUTEX_FAST || p->id==SQLITE_MUTEX_RECURSIVE );
   DeleteCriticalSection(&p->mutex);
   sqlite3_free(p);
@@ -16425,6 +17261,7 @@
 #endif
   EnterCriticalSection(&p->mutex);
 #ifdef SQLITE_DEBUG
+  assert( p->nRef>0 || p->owner==0 );
   p->owner = tid; 
   p->nRef++;
   if( p->trace ){
@@ -16478,6 +17315,7 @@
   assert( p->nRef>0 );
   assert( p->owner==tid );
   p->nRef--;
+  if( p->nRef==0 ) p->owner = 0;
   assert( p->nRef==0 || p->id==SQLITE_MUTEX_RECURSIVE );
 #endif
   LeaveCriticalSection(&p->mutex);
@@ -16528,6 +17366,66 @@
 */
 
 /*
+** Attempt to release up to n bytes of non-essential memory currently
+** held by SQLite. An example of non-essential memory is memory used to
+** cache database pages that are not currently in use.
+*/
+SQLITE_API int sqlite3_release_memory(int n){
+#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
+  return sqlite3PcacheReleaseMemory(n);
+#else
+  /* IMPLEMENTATION-OF: R-34391-24921 The sqlite3_release_memory() routine
+  ** is a no-op returning zero if SQLite is not compiled with
+  ** SQLITE_ENABLE_MEMORY_MANAGEMENT. */
+  UNUSED_PARAMETER(n);
+  return 0;
+#endif
+}
+
+/*
+** An instance of the following object records the location of
+** each unused scratch buffer.
+*/
+typedef struct ScratchFreeslot {
+  struct ScratchFreeslot *pNext;   /* Next unused scratch buffer */
+} ScratchFreeslot;
+
+/*
+** State information local to the memory allocation subsystem.
+*/
+static SQLITE_WSD struct Mem0Global {
+  sqlite3_mutex *mutex;         /* Mutex to serialize access */
+
+  /*
+  ** The alarm callback and its arguments.  The mem0.mutex lock will
+  ** be held while the callback is running.  Recursive calls into
+  ** the memory subsystem are allowed, but no new callbacks will be
+  ** issued.
+  */
+  sqlite3_int64 alarmThreshold;
+  void (*alarmCallback)(void*, sqlite3_int64,int);
+  void *alarmArg;
+
+  /*
+  ** Pointers to the end of sqlite3GlobalConfig.pScratch memory
+  ** (so that a range test can be used to determine if an allocation
+  ** being freed came from pScratch) and a pointer to the list of
+  ** unused scratch allocations.
+  */
+  void *pScratchEnd;
+  ScratchFreeslot *pScratchFree;
+  u32 nScratchFree;
+
+  /*
+  ** True if heap is nearly "full" where "full" is defined by the
+  ** sqlite3_soft_heap_limit() setting.
+  */
+  int nearlyFull;
+} mem0 = { 0, 0, 0, 0, 0, 0, 0 };
+
+#define mem0 GLOBAL(struct Mem0Global, mem0)
+
+/*
 ** This routine runs when the memory allocator sees that the
 ** total memory allocation is about to exceed the soft heap
 ** limit.
@@ -16542,79 +17440,67 @@
 }
 
 /*
+** Change the alarm callback
+*/
+static int sqlite3MemoryAlarm(
+  void(*xCallback)(void *pArg, sqlite3_int64 used,int N),
+  void *pArg,
+  sqlite3_int64 iThreshold
+){
+  int nUsed;
+  sqlite3_mutex_enter(mem0.mutex);
+  mem0.alarmCallback = xCallback;
+  mem0.alarmArg = pArg;
+  mem0.alarmThreshold = iThreshold;
+  nUsed = sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED);
+  mem0.nearlyFull = (iThreshold>0 && iThreshold<=nUsed);
+  sqlite3_mutex_leave(mem0.mutex);
+  return SQLITE_OK;
+}
+
+#ifndef SQLITE_OMIT_DEPRECATED
+/*
+** Deprecated external interface.  Internal/core SQLite code
+** should call sqlite3MemoryAlarm.
+*/
+SQLITE_API int sqlite3_memory_alarm(
+  void(*xCallback)(void *pArg, sqlite3_int64 used,int N),
+  void *pArg,
+  sqlite3_int64 iThreshold
+){
+  return sqlite3MemoryAlarm(xCallback, pArg, iThreshold);
+}
+#endif
+
+/*
 ** Set the soft heap-size limit for the library. Passing a zero or 
 ** negative value indicates no limit.
 */
-SQLITE_API void sqlite3_soft_heap_limit(int n){
-  sqlite3_uint64 iLimit;
-  int overage;
-  if( n<0 ){
-    iLimit = 0;
-  }else{
-    iLimit = n;
-  }
+SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 n){
+  sqlite3_int64 priorLimit;
+  sqlite3_int64 excess;
 #ifndef SQLITE_OMIT_AUTOINIT
   sqlite3_initialize();
 #endif
-  if( iLimit>0 ){
-    sqlite3MemoryAlarm(softHeapLimitEnforcer, 0, iLimit);
+  sqlite3_mutex_enter(mem0.mutex);
+  priorLimit = mem0.alarmThreshold;
+  sqlite3_mutex_leave(mem0.mutex);
+  if( n<0 ) return priorLimit;
+  if( n>0 ){
+    sqlite3MemoryAlarm(softHeapLimitEnforcer, 0, n);
   }else{
     sqlite3MemoryAlarm(0, 0, 0);
   }
-  overage = (int)(sqlite3_memory_used() - (i64)n);
-  if( overage>0 ){
-    sqlite3_release_memory(overage);
-  }
+  excess = sqlite3_memory_used() - n;
+  if( excess>0 ) sqlite3_release_memory(excess & 0x7fffffff);
+  return priorLimit;
 }
-
-/*
-** Attempt to release up to n bytes of non-essential memory currently
-** held by SQLite. An example of non-essential memory is memory used to
-** cache database pages that are not currently in use.
-*/
-SQLITE_API int sqlite3_release_memory(int n){
-#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
-  int nRet = 0;
-  nRet += sqlite3PcacheReleaseMemory(n-nRet);
-  return nRet;
-#else
-  UNUSED_PARAMETER(n);
-  return SQLITE_OK;
-#endif
+SQLITE_API void sqlite3_soft_heap_limit(int n){
+  if( n<0 ) n = 0;
+  sqlite3_soft_heap_limit64(n);
 }
 
 /*
-** State information local to the memory allocation subsystem.
-*/
-static SQLITE_WSD struct Mem0Global {
-  /* Number of free pages for scratch and page-cache memory */
-  u32 nScratchFree;
-  u32 nPageFree;
-
-  sqlite3_mutex *mutex;         /* Mutex to serialize access */
-
-  /*
-  ** The alarm callback and its arguments.  The mem0.mutex lock will
-  ** be held while the callback is running.  Recursive calls into
-  ** the memory subsystem are allowed, but no new callbacks will be
-  ** issued.
-  */
-  sqlite3_int64 alarmThreshold;
-  void (*alarmCallback)(void*, sqlite3_int64,int);
-  void *alarmArg;
-
-  /*
-  ** Pointers to the end of sqlite3GlobalConfig.pScratch and
-  ** sqlite3GlobalConfig.pPage to a block of memory that records
-  ** which pages are available.
-  */
-  u32 *aScratchFree;
-  u32 *aPageFree;
-} mem0 = { 0, 0, 0, 0, 0, 0, 0, 0 };
-
-#define mem0 GLOBAL(struct Mem0Global, mem0)
-
-/*
 ** Initialize the memory allocation subsystem.
 */
 SQLITE_PRIVATE int sqlite3MallocInit(void){
@@ -16626,37 +17512,46 @@
     mem0.mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MEM);
   }
   if( sqlite3GlobalConfig.pScratch && sqlite3GlobalConfig.szScratch>=100
-      && sqlite3GlobalConfig.nScratch>=0 ){
-    int i;
-    sqlite3GlobalConfig.szScratch = ROUNDDOWN8(sqlite3GlobalConfig.szScratch-4);
-    mem0.aScratchFree = (u32*)&((char*)sqlite3GlobalConfig.pScratch)
-                  [sqlite3GlobalConfig.szScratch*sqlite3GlobalConfig.nScratch];
-    for(i=0; i<sqlite3GlobalConfig.nScratch; i++){ mem0.aScratchFree[i] = i; }
-    mem0.nScratchFree = sqlite3GlobalConfig.nScratch;
+      && sqlite3GlobalConfig.nScratch>0 ){
+    int i, n, sz;
+    ScratchFreeslot *pSlot;
+    sz = ROUNDDOWN8(sqlite3GlobalConfig.szScratch);
+    sqlite3GlobalConfig.szScratch = sz;
+    pSlot = (ScratchFreeslot*)sqlite3GlobalConfig.pScratch;
+    n = sqlite3GlobalConfig.nScratch;
+    mem0.pScratchFree = pSlot;
+    mem0.nScratchFree = n;
+    for(i=0; i<n-1; i++){
+      pSlot->pNext = (ScratchFreeslot*)(sz+(char*)pSlot);
+      pSlot = pSlot->pNext;
+    }
+    pSlot->pNext = 0;
+    mem0.pScratchEnd = (void*)&pSlot[1];
   }else{
+    mem0.pScratchEnd = 0;
     sqlite3GlobalConfig.pScratch = 0;
     sqlite3GlobalConfig.szScratch = 0;
+    sqlite3GlobalConfig.nScratch = 0;
   }
-  if( sqlite3GlobalConfig.pPage && sqlite3GlobalConfig.szPage>=512
-      && sqlite3GlobalConfig.nPage>=1 ){
-    int i;
-    int overhead;
-    int sz = ROUNDDOWN8(sqlite3GlobalConfig.szPage);
-    int n = sqlite3GlobalConfig.nPage;
-    overhead = (4*n + sz - 1)/sz;
-    sqlite3GlobalConfig.nPage -= overhead;
-    mem0.aPageFree = (u32*)&((char*)sqlite3GlobalConfig.pPage)
-                  [sqlite3GlobalConfig.szPage*sqlite3GlobalConfig.nPage];
-    for(i=0; i<sqlite3GlobalConfig.nPage; i++){ mem0.aPageFree[i] = i; }
-    mem0.nPageFree = sqlite3GlobalConfig.nPage;
-  }else{
+  if( sqlite3GlobalConfig.pPage==0 || sqlite3GlobalConfig.szPage<512
+      || sqlite3GlobalConfig.nPage<1 ){
     sqlite3GlobalConfig.pPage = 0;
     sqlite3GlobalConfig.szPage = 0;
+    sqlite3GlobalConfig.nPage = 0;
   }
   return sqlite3GlobalConfig.m.xInit(sqlite3GlobalConfig.m.pAppData);
 }
 
 /*
+** Return true if the heap is currently under memory pressure - in other
+** words if the amount of heap used is close to the limit set by
+** sqlite3_soft_heap_limit().
+*/
+SQLITE_PRIVATE int sqlite3HeapNearlyFull(void){
+  return mem0.nearlyFull;
+}
+
+/*
 ** Deinitialize the memory allocation subsystem.
 */
 SQLITE_PRIVATE void sqlite3MallocEnd(void){
@@ -16691,36 +17586,6 @@
 }
 
 /*
-** Change the alarm callback
-*/
-SQLITE_PRIVATE int sqlite3MemoryAlarm(
-  void(*xCallback)(void *pArg, sqlite3_int64 used,int N),
-  void *pArg,
-  sqlite3_int64 iThreshold
-){
-  sqlite3_mutex_enter(mem0.mutex);
-  mem0.alarmCallback = xCallback;
-  mem0.alarmArg = pArg;
-  mem0.alarmThreshold = iThreshold;
-  sqlite3_mutex_leave(mem0.mutex);
-  return SQLITE_OK;
-}
-
-#ifndef SQLITE_OMIT_DEPRECATED
-/*
-** Deprecated external interface.  Internal/core SQLite code
-** should call sqlite3MemoryAlarm.
-*/
-SQLITE_API int sqlite3_memory_alarm(
-  void(*xCallback)(void *pArg, sqlite3_int64 used,int N),
-  void *pArg,
-  sqlite3_int64 iThreshold
-){
-  return sqlite3MemoryAlarm(xCallback, pArg, iThreshold);
-}
-#endif
-
-/*
 ** Trigger the alarm 
 */
 static void sqlite3MallocAlarm(int nByte){
@@ -16752,17 +17617,23 @@
   if( mem0.alarmCallback!=0 ){
     int nUsed = sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED);
     if( nUsed+nFull >= mem0.alarmThreshold ){
+      mem0.nearlyFull = 1;
       sqlite3MallocAlarm(nFull);
+    }else{
+      mem0.nearlyFull = 0;
     }
   }
   p = sqlite3GlobalConfig.m.xMalloc(nFull);
+#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
   if( p==0 && mem0.alarmCallback ){
     sqlite3MallocAlarm(nFull);
     p = sqlite3GlobalConfig.m.xMalloc(nFull);
   }
+#endif
   if( p ){
     nFull = sqlite3MallocSize(p);
     sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, nFull);
+    sqlite3StatusAdd(SQLITE_STATUS_MALLOC_COUNT, 1);
   }
   *pp = p;
   return nFull;
@@ -16774,7 +17645,9 @@
 */
 SQLITE_PRIVATE void *sqlite3Malloc(int n){
   void *p;
-  if( n<=0 || n>=0x7fffff00 ){
+  if( n<=0               /* IMP: R-65312-04917 */ 
+   || n>=0x7fffff00
+  ){
     /* A memory allocation of a number of bytes which is near the maximum
     ** signed integer value might cause an integer overflow inside of the
     ** xMalloc().  Hence we limit the maximum size to 0x7fffff00, giving
@@ -16788,6 +17661,7 @@
   }else{
     p = sqlite3GlobalConfig.m.xMalloc(n);
   }
+  assert( EIGHT_BYTE_ALIGNMENT(p) );  /* IMP: R-04675-44850 */
   return p;
 }
 
@@ -16826,81 +17700,42 @@
   void *p;
   assert( n>0 );
 
+  sqlite3_mutex_enter(mem0.mutex);
+  if( mem0.nScratchFree && sqlite3GlobalConfig.szScratch>=n ){
+    p = mem0.pScratchFree;
+    mem0.pScratchFree = mem0.pScratchFree->pNext;
+    mem0.nScratchFree--;
+    sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_USED, 1);
+    sqlite3StatusSet(SQLITE_STATUS_SCRATCH_SIZE, n);
+    sqlite3_mutex_leave(mem0.mutex);
+  }else{
+    if( sqlite3GlobalConfig.bMemstat ){
+      sqlite3StatusSet(SQLITE_STATUS_SCRATCH_SIZE, n);
+      n = mallocWithAlarm(n, &p);
+      if( p ) sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_OVERFLOW, n);
+      sqlite3_mutex_leave(mem0.mutex);
+    }else{
+      sqlite3_mutex_leave(mem0.mutex);
+      p = sqlite3GlobalConfig.m.xMalloc(n);
+    }
+    sqlite3MemdebugSetType(p, MEMTYPE_SCRATCH);
+  }
+  assert( sqlite3_mutex_notheld(mem0.mutex) );
+
+
 #if SQLITE_THREADSAFE==0 && !defined(NDEBUG)
-  /* Verify that no more than two scratch allocation per thread
-  ** is outstanding at one time.  (This is only checked in the
+  /* Verify that no more than two scratch allocations per thread
+  ** are outstanding at one time.  (This is only checked in the
   ** single-threaded case since checking in the multi-threaded case
   ** would be much more complicated.) */
   assert( scratchAllocOut<=1 );
-#endif
-
-  if( sqlite3GlobalConfig.szScratch<n ){
-    goto scratch_overflow;
-  }else{  
-    sqlite3_mutex_enter(mem0.mutex);
-    if( mem0.nScratchFree==0 ){
-      sqlite3_mutex_leave(mem0.mutex);
-      goto scratch_overflow;
-    }else{
-      int i;
-      i = mem0.aScratchFree[--mem0.nScratchFree];
-      i *= sqlite3GlobalConfig.szScratch;
-      sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_USED, 1);
-      sqlite3StatusSet(SQLITE_STATUS_SCRATCH_SIZE, n);
-      sqlite3_mutex_leave(mem0.mutex);
-      p = (void*)&((char*)sqlite3GlobalConfig.pScratch)[i];
-      assert(  (((u8*)p - (u8*)0) & 7)==0 );
-    }
-  }
-#if SQLITE_THREADSAFE==0 && !defined(NDEBUG)
-  scratchAllocOut = p!=0;
+  if( p ) scratchAllocOut++;
 #endif
 
   return p;
-
-scratch_overflow:
-  if( sqlite3GlobalConfig.bMemstat ){
-    sqlite3_mutex_enter(mem0.mutex);
-    sqlite3StatusSet(SQLITE_STATUS_SCRATCH_SIZE, n);
-    n = mallocWithAlarm(n, &p);
-    if( p ) sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_OVERFLOW, n);
-    sqlite3_mutex_leave(mem0.mutex);
-  }else{
-    p = sqlite3GlobalConfig.m.xMalloc(n);
-  }
-  sqlite3MemdebugSetType(p, MEMTYPE_SCRATCH);
-#if SQLITE_THREADSAFE==0 && !defined(NDEBUG)
-  scratchAllocOut = p!=0;
-#endif
-  return p;    
 }
 SQLITE_PRIVATE void sqlite3ScratchFree(void *p){
   if( p ){
-    if( sqlite3GlobalConfig.pScratch==0
-           || p<sqlite3GlobalConfig.pScratch
-           || p>=(void*)mem0.aScratchFree ){
-      assert( sqlite3MemdebugHasType(p, MEMTYPE_SCRATCH) );
-      sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
-      if( sqlite3GlobalConfig.bMemstat ){
-        int iSize = sqlite3MallocSize(p);
-        sqlite3_mutex_enter(mem0.mutex);
-        sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_OVERFLOW, -iSize);
-        sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, -iSize);
-        sqlite3GlobalConfig.m.xFree(p);
-        sqlite3_mutex_leave(mem0.mutex);
-      }else{
-        sqlite3GlobalConfig.m.xFree(p);
-      }
-    }else{
-      int i;
-      i = (int)((u8*)p - (u8*)sqlite3GlobalConfig.pScratch);
-      i /= sqlite3GlobalConfig.szScratch;
-      assert( i>=0 && i<sqlite3GlobalConfig.nScratch );
-      sqlite3_mutex_enter(mem0.mutex);
-      assert( mem0.nScratchFree<(u32)sqlite3GlobalConfig.nScratch );
-      mem0.aScratchFree[mem0.nScratchFree++] = i;
-      sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_USED, -1);
-      sqlite3_mutex_leave(mem0.mutex);
 
 #if SQLITE_THREADSAFE==0 && !defined(NDEBUG)
     /* Verify that no more than two scratch allocation per thread
@@ -16908,9 +17743,36 @@
     ** single-threaded case since checking in the multi-threaded case
     ** would be much more complicated.) */
     assert( scratchAllocOut>=1 && scratchAllocOut<=2 );
-    scratchAllocOut = 0;
+    scratchAllocOut--;
 #endif
 
+    if( p>=sqlite3GlobalConfig.pScratch && p<mem0.pScratchEnd ){
+      /* Release memory from the SQLITE_CONFIG_SCRATCH allocation */
+      ScratchFreeslot *pSlot;
+      pSlot = (ScratchFreeslot*)p;
+      sqlite3_mutex_enter(mem0.mutex);
+      pSlot->pNext = mem0.pScratchFree;
+      mem0.pScratchFree = pSlot;
+      mem0.nScratchFree++;
+      assert( mem0.nScratchFree<=sqlite3GlobalConfig.nScratch );
+      sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_USED, -1);
+      sqlite3_mutex_leave(mem0.mutex);
+    }else{
+      /* Release memory back to the heap */
+      assert( sqlite3MemdebugHasType(p, MEMTYPE_SCRATCH) );
+      assert( sqlite3MemdebugNoType(p, ~MEMTYPE_SCRATCH) );
+      sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
+      if( sqlite3GlobalConfig.bMemstat ){
+        int iSize = sqlite3MallocSize(p);
+        sqlite3_mutex_enter(mem0.mutex);
+        sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_OVERFLOW, -iSize);
+        sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, -iSize);
+        sqlite3StatusAdd(SQLITE_STATUS_MALLOC_COUNT, -1);
+        sqlite3GlobalConfig.m.xFree(p);
+        sqlite3_mutex_leave(mem0.mutex);
+      }else{
+        sqlite3GlobalConfig.m.xFree(p);
+      }
     }
   }
 }
@@ -16920,7 +17782,7 @@
 */
 #ifndef SQLITE_OMIT_LOOKASIDE
 static int isLookaside(sqlite3 *db, void *p){
-  return db && p && p>=db->lookaside.pStart && p<db->lookaside.pEnd;
+  return p && p>=db->lookaside.pStart && p<db->lookaside.pEnd;
 }
 #else
 #define isLookaside(A,B) 0
@@ -16932,15 +17794,17 @@
 */
 SQLITE_PRIVATE int sqlite3MallocSize(void *p){
   assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
+  assert( sqlite3MemdebugNoType(p, MEMTYPE_DB) );
   return sqlite3GlobalConfig.m.xSize(p);
 }
 SQLITE_PRIVATE int sqlite3DbMallocSize(sqlite3 *db, void *p){
   assert( db==0 || sqlite3_mutex_held(db->mutex) );
-  if( isLookaside(db, p) ){
+  if( db && isLookaside(db, p) ){
     return db->lookaside.sz;
   }else{
-    assert( sqlite3MemdebugHasType(p,
-             db ? (MEMTYPE_DB|MEMTYPE_HEAP) : MEMTYPE_HEAP) );
+    assert( sqlite3MemdebugHasType(p, MEMTYPE_DB) );
+    assert( sqlite3MemdebugHasType(p, MEMTYPE_LOOKASIDE|MEMTYPE_HEAP) );
+    assert( db!=0 || sqlite3MemdebugNoType(p, MEMTYPE_LOOKASIDE) );
     return sqlite3GlobalConfig.m.xSize(p);
   }
 }
@@ -16949,11 +17813,13 @@
 ** Free memory previously obtained from sqlite3Malloc().
 */
 SQLITE_API void sqlite3_free(void *p){
-  if( p==0 ) return;
+  if( p==0 ) return;  /* IMP: R-49053-54554 */
+  assert( sqlite3MemdebugNoType(p, MEMTYPE_DB) );
   assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
   if( sqlite3GlobalConfig.bMemstat ){
     sqlite3_mutex_enter(mem0.mutex);
     sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, -sqlite3MallocSize(p));
+    sqlite3StatusAdd(SQLITE_STATUS_MALLOC_COUNT, -1);
     sqlite3GlobalConfig.m.xFree(p);
     sqlite3_mutex_leave(mem0.mutex);
   }else{
@@ -16967,16 +17833,24 @@
 */
 SQLITE_PRIVATE void sqlite3DbFree(sqlite3 *db, void *p){
   assert( db==0 || sqlite3_mutex_held(db->mutex) );
-  if( isLookaside(db, p) ){
-    LookasideSlot *pBuf = (LookasideSlot*)p;
-    pBuf->pNext = db->lookaside.pFree;
-    db->lookaside.pFree = pBuf;
-    db->lookaside.nOut--;
-  }else{
-    assert( sqlite3MemdebugHasType(p, MEMTYPE_DB|MEMTYPE_HEAP) );
-    sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
-    sqlite3_free(p);
+  if( db ){
+    if( db->pnBytesFreed ){
+      *db->pnBytesFreed += sqlite3DbMallocSize(db, p);
+      return;
+    }
+    if( isLookaside(db, p) ){
+      LookasideSlot *pBuf = (LookasideSlot*)p;
+      pBuf->pNext = db->lookaside.pFree;
+      db->lookaside.pFree = pBuf;
+      db->lookaside.nOut--;
+      return;
+    }
   }
+  assert( sqlite3MemdebugHasType(p, MEMTYPE_DB) );
+  assert( sqlite3MemdebugHasType(p, MEMTYPE_LOOKASIDE|MEMTYPE_HEAP) );
+  assert( db!=0 || sqlite3MemdebugNoType(p, MEMTYPE_LOOKASIDE) );
+  sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
+  sqlite3_free(p);
 }
 
 /*
@@ -16986,10 +17860,10 @@
   int nOld, nNew;
   void *pNew;
   if( pOld==0 ){
-    return sqlite3Malloc(nBytes);
+    return sqlite3Malloc(nBytes); /* IMP: R-28354-25769 */
   }
   if( nBytes<=0 ){
-    sqlite3_free(pOld);
+    sqlite3_free(pOld); /* IMP: R-31593-10574 */
     return 0;
   }
   if( nBytes>=0x7fffff00 ){
@@ -16997,6 +17871,9 @@
     return 0;
   }
   nOld = sqlite3MallocSize(pOld);
+  /* IMPLEMENTATION-OF: R-46199-30249 SQLite guarantees that the second
+  ** argument to xRealloc is always a value returned by a prior call to
+  ** xRoundup. */
   nNew = sqlite3GlobalConfig.m.xRoundup(nBytes);
   if( nOld==nNew ){
     pNew = pOld;
@@ -17008,6 +17885,7 @@
       sqlite3MallocAlarm(nNew-nOld);
     }
     assert( sqlite3MemdebugHasType(pOld, MEMTYPE_HEAP) );
+    assert( sqlite3MemdebugNoType(pOld, ~MEMTYPE_HEAP) );
     pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
     if( pNew==0 && mem0.alarmCallback ){
       sqlite3MallocAlarm(nBytes);
@@ -17021,6 +17899,7 @@
   }else{
     pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
   }
+  assert( EIGHT_BYTE_ALIGNMENT(pNew) ); /* IMP: R-04675-44850 */
   return pNew;
 }
 
@@ -17080,6 +17959,7 @@
 SQLITE_PRIVATE void *sqlite3DbMallocRaw(sqlite3 *db, int n){
   void *p;
   assert( db==0 || sqlite3_mutex_held(db->mutex) );
+  assert( db==0 || db->pnBytesFreed==0 );
 #ifndef SQLITE_OMIT_LOOKASIDE
   if( db ){
     LookasideSlot *pBuf;
@@ -17105,8 +17985,8 @@
   if( !p && db ){
     db->mallocFailed = 1;
   }
-  sqlite3MemdebugSetType(p,
-            (db && db->lookaside.bEnabled) ? MEMTYPE_DB : MEMTYPE_HEAP);
+  sqlite3MemdebugSetType(p, MEMTYPE_DB |
+         ((db && db->lookaside.bEnabled) ? MEMTYPE_LOOKASIDE : MEMTYPE_HEAP));
   return p;
 }
 
@@ -17132,14 +18012,16 @@
         sqlite3DbFree(db, p);
       }
     }else{
-      assert( sqlite3MemdebugHasType(p, MEMTYPE_DB|MEMTYPE_HEAP) );
+      assert( sqlite3MemdebugHasType(p, MEMTYPE_DB) );
+      assert( sqlite3MemdebugHasType(p, MEMTYPE_LOOKASIDE|MEMTYPE_HEAP) );
       sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
       pNew = sqlite3_realloc(p, n);
       if( !pNew ){
+        sqlite3MemdebugSetType(p, MEMTYPE_DB|MEMTYPE_HEAP);
         db->mallocFailed = 1;
       }
-      sqlite3MemdebugSetType(pNew,
-            db->lookaside.bEnabled ? MEMTYPE_DB : MEMTYPE_HEAP);
+      sqlite3MemdebugSetType(pNew, MEMTYPE_DB | 
+            (db->lookaside.bEnabled ? MEMTYPE_LOOKASIDE : MEMTYPE_HEAP));
     }
   }
   return pNew;
@@ -18012,7 +18894,11 @@
       }else{
         p->nAlloc = (int)szNew;
       }
-      zNew = sqlite3DbMallocRaw(p->db, p->nAlloc );
+      if( p->useMalloc==1 ){
+        zNew = sqlite3DbMallocRaw(p->db, p->nAlloc );
+      }else{
+        zNew = sqlite3_malloc(p->nAlloc);
+      }
       if( zNew ){
         memcpy(zNew, p->zText, p->nChar);
         sqlite3StrAccumReset(p);
@@ -18037,7 +18923,11 @@
   if( p->zText ){
     p->zText[p->nChar] = 0;
     if( p->useMalloc && p->zText==p->zBase ){
-      p->zText = sqlite3DbMallocRaw(p->db, p->nChar+1 );
+      if( p->useMalloc==1 ){
+        p->zText = sqlite3DbMallocRaw(p->db, p->nChar+1 );
+      }else{
+        p->zText = sqlite3_malloc(p->nChar+1);
+      }
       if( p->zText ){
         memcpy(p->zText, p->zBase, p->nChar+1);
       }else{
@@ -18053,7 +18943,11 @@
 */
 SQLITE_PRIVATE void sqlite3StrAccumReset(StrAccum *p){
   if( p->zText!=p->zBase ){
-    sqlite3DbFree(p->db, p->zText);
+    if( p->useMalloc==1 ){
+      sqlite3DbFree(p->db, p->zText);
+    }else{
+      sqlite3_free(p->zText);
+    }
   }
   p->zText = 0;
 }
@@ -18135,6 +19029,7 @@
   if( sqlite3_initialize() ) return 0;
 #endif
   sqlite3StrAccumInit(&acc, zBase, sizeof(zBase), SQLITE_MAX_LENGTH);
+  acc.useMalloc = 2;
   sqlite3VXPrintf(&acc, 0, zFormat, ap);
   z = sqlite3StrAccumFinish(&acc);
   return z;
@@ -18428,429 +19323,6 @@
 **     0xfe 0xff   big-endian utf-16 follows
 **
 */
-/************** Include vdbeInt.h in the middle of utf.c *********************/
-/************** Begin file vdbeInt.h *****************************************/
-/*
-** 2003 September 6
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-** This is the header file for information that is private to the
-** VDBE.  This information used to all be at the top of the single
-** source code file "vdbe.c".  When that file became too big (over
-** 6000 lines long) it was split up into several smaller files and
-** this header information was factored out.
-*/
-#ifndef _VDBEINT_H_
-#define _VDBEINT_H_
-
-/*
-** SQL is translated into a sequence of instructions to be
-** executed by a virtual machine.  Each instruction is an instance
-** of the following structure.
-*/
-typedef struct VdbeOp Op;
-
-/*
-** Boolean values
-*/
-typedef unsigned char Bool;
-
-/*
-** A cursor is a pointer into a single BTree within a database file.
-** The cursor can seek to a BTree entry with a particular key, or
-** loop over all entries of the Btree.  You can also insert new BTree
-** entries or retrieve the key or data from the entry that the cursor
-** is currently pointing to.
-** 
-** Every cursor that the virtual machine has open is represented by an
-** instance of the following structure.
-**
-** If the VdbeCursor.isTriggerRow flag is set it means that this cursor is
-** really a single row that represents the NEW or OLD pseudo-table of
-** a row trigger.  The data for the row is stored in VdbeCursor.pData and
-** the rowid is in VdbeCursor.iKey.
-*/
-struct VdbeCursor {
-  BtCursor *pCursor;    /* The cursor structure of the backend */
-  int iDb;              /* Index of cursor database in db->aDb[] (or -1) */
-  i64 lastRowid;        /* Last rowid from a Next or NextIdx operation */
-  Bool zeroed;          /* True if zeroed out and ready for reuse */
-  Bool rowidIsValid;    /* True if lastRowid is valid */
-  Bool atFirst;         /* True if pointing to first entry */
-  Bool useRandomRowid;  /* Generate new record numbers semi-randomly */
-  Bool nullRow;         /* True if pointing to a row with no data */
-  Bool deferredMoveto;  /* A call to sqlite3BtreeMoveto() is needed */
-  Bool isTable;         /* True if a table requiring integer keys */
-  Bool isIndex;         /* True if an index containing keys only - no data */
-  i64 movetoTarget;     /* Argument to the deferred sqlite3BtreeMoveto() */
-  Btree *pBt;           /* Separate file holding temporary table */
-  int pseudoTableReg;   /* Register holding pseudotable content. */
-  KeyInfo *pKeyInfo;    /* Info about index keys needed by index cursors */
-  int nField;           /* Number of fields in the header */
-  i64 seqCount;         /* Sequence counter */
-  sqlite3_vtab_cursor *pVtabCursor;  /* The cursor for a virtual table */
-  const sqlite3_module *pModule;     /* Module for cursor pVtabCursor */
-
-  /* Result of last sqlite3BtreeMoveto() done by an OP_NotExists or 
-  ** OP_IsUnique opcode on this cursor. */
-  int seekResult;
-
-  /* Cached information about the header for the data record that the
-  ** cursor is currently pointing to.  Only valid if cacheStatus matches
-  ** Vdbe.cacheCtr.  Vdbe.cacheCtr will never take on the value of
-  ** CACHE_STALE and so setting cacheStatus=CACHE_STALE guarantees that
-  ** the cache is out of date.
-  **
-  ** aRow might point to (ephemeral) data for the current row, or it might
-  ** be NULL.
-  */
-  u32 cacheStatus;      /* Cache is valid if this matches Vdbe.cacheCtr */
-  int payloadSize;      /* Total number of bytes in the record */
-  u32 *aType;           /* Type values for all entries in the record */
-  u32 *aOffset;         /* Cached offsets to the start of each columns data */
-  u8 *aRow;             /* Data for the current row, if all on one page */
-};
-typedef struct VdbeCursor VdbeCursor;
-
-/*
-** When a sub-program is executed (OP_Program), a structure of this type
-** is allocated to store the current value of the program counter, as
-** well as the current memory cell array and various other frame specific
-** values stored in the Vdbe struct. When the sub-program is finished, 
-** these values are copied back to the Vdbe from the VdbeFrame structure,
-** restoring the state of the VM to as it was before the sub-program
-** began executing.
-**
-** Frames are stored in a linked list headed at Vdbe.pParent. Vdbe.pParent
-** is the parent of the current frame, or zero if the current frame
-** is the main Vdbe program.
-*/
-typedef struct VdbeFrame VdbeFrame;
-struct VdbeFrame {
-  Vdbe *v;                /* VM this frame belongs to */
-  int pc;                 /* Program Counter */
-  Op *aOp;                /* Program instructions */
-  int nOp;                /* Size of aOp array */
-  Mem *aMem;              /* Array of memory cells */
-  int nMem;               /* Number of entries in aMem */
-  VdbeCursor **apCsr;     /* Element of Vdbe cursors */
-  u16 nCursor;            /* Number of entries in apCsr */
-  void *token;            /* Copy of SubProgram.token */
-  int nChildMem;          /* Number of memory cells for child frame */
-  int nChildCsr;          /* Number of cursors for child frame */
-  i64 lastRowid;          /* Last insert rowid (sqlite3.lastRowid) */
-  int nChange;            /* Statement changes (Vdbe.nChanges)     */
-  VdbeFrame *pParent;     /* Parent of this frame */
-};
-
-#define VdbeFrameMem(p) ((Mem *)&((u8 *)p)[ROUND8(sizeof(VdbeFrame))])
-
-/*
-** A value for VdbeCursor.cacheValid that means the cache is always invalid.
-*/
-#define CACHE_STALE 0
-
-/*
-** Internally, the vdbe manipulates nearly all SQL values as Mem
-** structures. Each Mem struct may cache multiple representations (string,
-** integer etc.) of the same value.  A value (and therefore Mem structure)
-** has the following properties:
-**
-** Each value has a manifest type. The manifest type of the value stored
-** in a Mem struct is returned by the MemType(Mem*) macro. The type is
-** one of SQLITE_NULL, SQLITE_INTEGER, SQLITE_REAL, SQLITE_TEXT or
-** SQLITE_BLOB.
-*/
-struct Mem {
-  union {
-    i64 i;              /* Integer value. */
-    int nZero;          /* Used when bit MEM_Zero is set in flags */
-    FuncDef *pDef;      /* Used only when flags==MEM_Agg */
-    RowSet *pRowSet;    /* Used only when flags==MEM_RowSet */
-    VdbeFrame *pFrame;  /* Used when flags==MEM_Frame */
-  } u;
-  double r;           /* Real value */
-  sqlite3 *db;        /* The associated database connection */
-  char *z;            /* String or BLOB value */
-  int n;              /* Number of characters in string value, excluding '\0' */
-  u16 flags;          /* Some combination of MEM_Null, MEM_Str, MEM_Dyn, etc. */
-  u8  type;           /* One of SQLITE_NULL, SQLITE_TEXT, SQLITE_INTEGER, etc */
-  u8  enc;            /* SQLITE_UTF8, SQLITE_UTF16BE, SQLITE_UTF16LE */
-  void (*xDel)(void *);  /* If not null, call this function to delete Mem.z */
-  char *zMalloc;      /* Dynamic buffer allocated by sqlite3_malloc() */
-};
-
-/* One or more of the following flags are set to indicate the validOK
-** representations of the value stored in the Mem struct.
-**
-** If the MEM_Null flag is set, then the value is an SQL NULL value.
-** No other flags may be set in this case.
-**
-** If the MEM_Str flag is set then Mem.z points at a string representation.
-** Usually this is encoded in the same unicode encoding as the main
-** database (see below for exceptions). If the MEM_Term flag is also
-** set, then the string is nul terminated. The MEM_Int and MEM_Real 
-** flags may coexist with the MEM_Str flag.
-**
-** Multiple of these values can appear in Mem.flags.  But only one
-** at a time can appear in Mem.type.
-*/
-#define MEM_Null      0x0001   /* Value is NULL */
-#define MEM_Str       0x0002   /* Value is a string */
-#define MEM_Int       0x0004   /* Value is an integer */
-#define MEM_Real      0x0008   /* Value is a real number */
-#define MEM_Blob      0x0010   /* Value is a BLOB */
-#define MEM_RowSet    0x0020   /* Value is a RowSet object */
-#define MEM_Frame     0x0040   /* Value is a VdbeFrame object */
-#define MEM_TypeMask  0x00ff   /* Mask of type bits */
-
-/* Whenever Mem contains a valid string or blob representation, one of
-** the following flags must be set to determine the memory management
-** policy for Mem.z.  The MEM_Term flag tells us whether or not the
-** string is \000 or \u0000 terminated
-*/
-#define MEM_Term      0x0200   /* String rep is nul terminated */
-#define MEM_Dyn       0x0400   /* Need to call sqliteFree() on Mem.z */
-#define MEM_Static    0x0800   /* Mem.z points to a static string */
-#define MEM_Ephem     0x1000   /* Mem.z points to an ephemeral string */
-#define MEM_Agg       0x2000   /* Mem.z points to an agg function context */
-#define MEM_Zero      0x4000   /* Mem.i contains count of 0s appended to blob */
-
-#ifdef SQLITE_OMIT_INCRBLOB
-  #undef MEM_Zero
-  #define MEM_Zero 0x0000
-#endif
-
-
-/*
-** Clear any existing type flags from a Mem and replace them with f
-*/
-#define MemSetTypeFlag(p, f) \
-   ((p)->flags = ((p)->flags&~(MEM_TypeMask|MEM_Zero))|f)
-
-
-/* A VdbeFunc is just a FuncDef (defined in sqliteInt.h) that contains
-** additional information about auxiliary information bound to arguments
-** of the function.  This is used to implement the sqlite3_get_auxdata()
-** and sqlite3_set_auxdata() APIs.  The "auxdata" is some auxiliary data
-** that can be associated with a constant argument to a function.  This
-** allows functions such as "regexp" to compile their constant regular
-** expression argument once and reused the compiled code for multiple
-** invocations.
-*/
-struct VdbeFunc {
-  FuncDef *pFunc;               /* The definition of the function */
-  int nAux;                     /* Number of entries allocated for apAux[] */
-  struct AuxData {
-    void *pAux;                   /* Aux data for the i-th argument */
-    void (*xDelete)(void *);      /* Destructor for the aux data */
-  } apAux[1];                   /* One slot for each function argument */
-};
-
-/*
-** The "context" argument for a installable function.  A pointer to an
-** instance of this structure is the first argument to the routines used
-** implement the SQL functions.
-**
-** There is a typedef for this structure in sqlite.h.  So all routines,
-** even the public interface to SQLite, can use a pointer to this structure.
-** But this file is the only place where the internal details of this
-** structure are known.
-**
-** This structure is defined inside of vdbeInt.h because it uses substructures
-** (Mem) which are only defined there.
-*/
-struct sqlite3_context {
-  FuncDef *pFunc;       /* Pointer to function information.  MUST BE FIRST */
-  VdbeFunc *pVdbeFunc;  /* Auxilary data, if created. */
-  Mem s;                /* The return value is stored here */
-  Mem *pMem;            /* Memory cell used to store aggregate context */
-  int isError;          /* Error code returned by the function. */
-  CollSeq *pColl;       /* Collating sequence */
-};
-
-/*
-** A Set structure is used for quick testing to see if a value
-** is part of a small set.  Sets are used to implement code like
-** this:
-**            x.y IN ('hi','hoo','hum')
-*/
-typedef struct Set Set;
-struct Set {
-  Hash hash;             /* A set is just a hash table */
-  HashElem *prev;        /* Previously accessed hash elemen */
-};
-
-/*
-** An instance of the virtual machine.  This structure contains the complete
-** state of the virtual machine.
-**
-** The "sqlite3_stmt" structure pointer that is returned by sqlite3_compile()
-** is really a pointer to an instance of this structure.
-**
-** The Vdbe.inVtabMethod variable is set to non-zero for the duration of
-** any virtual table method invocations made by the vdbe program. It is
-** set to 2 for xDestroy method calls and 1 for all other methods. This
-** variable is used for two purposes: to allow xDestroy methods to execute
-** "DROP TABLE" statements and to prevent some nasty side effects of
-** malloc failure when SQLite is invoked recursively by a virtual table 
-** method function.
-*/
-struct Vdbe {
-  sqlite3 *db;            /* The database connection that owns this statement */
-  Vdbe *pPrev,*pNext;     /* Linked list of VDBEs with the same Vdbe.db */
-  int nOp;                /* Number of instructions in the program */
-  int nOpAlloc;           /* Number of slots allocated for aOp[] */
-  Op *aOp;                /* Space to hold the virtual machine's program */
-  int nLabel;             /* Number of labels used */
-  int nLabelAlloc;        /* Number of slots allocated in aLabel[] */
-  int *aLabel;            /* Space to hold the labels */
-  Mem **apArg;            /* Arguments to currently executing user function */
-  Mem *aColName;          /* Column names to return */
-  Mem *pResultSet;        /* Pointer to an array of results */
-  u16 nResColumn;         /* Number of columns in one row of the result set */
-  u16 nCursor;            /* Number of slots in apCsr[] */
-  VdbeCursor **apCsr;     /* One element of this array for each open cursor */
-  u8 errorAction;         /* Recovery action to do in case of an error */
-  u8 okVar;               /* True if azVar[] has been initialized */
-  ynVar nVar;             /* Number of entries in aVar[] */
-  Mem *aVar;              /* Values for the OP_Variable opcode. */
-  char **azVar;           /* Name of variables */
-  u32 magic;              /* Magic number for sanity checking */
-  int nMem;               /* Number of memory locations currently allocated */
-  Mem *aMem;              /* The memory locations */
-  u32 cacheCtr;           /* VdbeCursor row cache generation counter */
-  int pc;                 /* The program counter */
-  int rc;                 /* Value to return */
-  char *zErrMsg;          /* Error message written here */
-  u8 explain;             /* True if EXPLAIN present on SQL command */
-  u8 changeCntOn;         /* True to update the change-counter */
-  u8 expired;             /* True if the VM needs to be recompiled */
-  u8 runOnlyOnce;         /* Automatically expire on reset */
-  u8 minWriteFileFormat;  /* Minimum file format for writable database files */
-  u8 inVtabMethod;        /* See comments above */
-  u8 usesStmtJournal;     /* True if uses a statement journal */
-  u8 readOnly;            /* True for read-only statements */
-  u8 isPrepareV2;         /* True if prepared with prepare_v2() */
-  int nChange;            /* Number of db changes made since last reset */
-  int btreeMask;          /* Bitmask of db->aDb[] entries referenced */
-  i64 startTime;          /* Time when query started - used for profiling */
-  BtreeMutexArray aMutex; /* An array of Btree used here and needing locks */
-  int aCounter[3];        /* Counters used by sqlite3_stmt_status() */
-  char *zSql;             /* Text of the SQL statement that generated this */
-  void *pFree;            /* Free this when deleting the vdbe */
-  i64 nFkConstraint;      /* Number of imm. FK constraints this VM */
-  i64 nStmtDefCons;       /* Number of def. constraints when stmt started */
-  int iStatement;         /* Statement number (or 0 if has not opened stmt) */
-#ifdef SQLITE_DEBUG
-  FILE *trace;            /* Write an execution trace here, if not NULL */
-#endif
-  VdbeFrame *pFrame;      /* Parent frame */
-  int nFrame;             /* Number of frames in pFrame list */
-  u32 expmask;            /* Binding to these vars invalidates VM */
-};
-
-/*
-** The following are allowed values for Vdbe.magic
-*/
-#define VDBE_MAGIC_INIT     0x26bceaa5    /* Building a VDBE program */
-#define VDBE_MAGIC_RUN      0xbdf20da3    /* VDBE is ready to execute */
-#define VDBE_MAGIC_HALT     0x519c2973    /* VDBE has completed execution */
-#define VDBE_MAGIC_DEAD     0xb606c3c8    /* The VDBE has been deallocated */
-
-/*
-** Function prototypes
-*/
-SQLITE_PRIVATE void sqlite3VdbeFreeCursor(Vdbe *, VdbeCursor*);
-void sqliteVdbePopStack(Vdbe*,int);
-SQLITE_PRIVATE int sqlite3VdbeCursorMoveto(VdbeCursor*);
-#if defined(SQLITE_DEBUG) || defined(VDBE_PROFILE)
-SQLITE_PRIVATE void sqlite3VdbePrintOp(FILE*, int, Op*);
-#endif
-SQLITE_PRIVATE u32 sqlite3VdbeSerialTypeLen(u32);
-SQLITE_PRIVATE u32 sqlite3VdbeSerialType(Mem*, int);
-SQLITE_PRIVATE u32 sqlite3VdbeSerialPut(unsigned char*, int, Mem*, int);
-SQLITE_PRIVATE u32 sqlite3VdbeSerialGet(const unsigned char*, u32, Mem*);
-SQLITE_PRIVATE void sqlite3VdbeDeleteAuxData(VdbeFunc*, int);
-
-int sqlite2BtreeKeyCompare(BtCursor *, const void *, int, int, int *);
-SQLITE_PRIVATE int sqlite3VdbeIdxKeyCompare(VdbeCursor*,UnpackedRecord*,int*);
-SQLITE_PRIVATE int sqlite3VdbeIdxRowid(sqlite3*, BtCursor *, i64 *);
-SQLITE_PRIVATE int sqlite3MemCompare(const Mem*, const Mem*, const CollSeq*);
-SQLITE_PRIVATE int sqlite3VdbeExec(Vdbe*);
-SQLITE_PRIVATE int sqlite3VdbeList(Vdbe*);
-SQLITE_PRIVATE int sqlite3VdbeHalt(Vdbe*);
-SQLITE_PRIVATE int sqlite3VdbeChangeEncoding(Mem *, int);
-SQLITE_PRIVATE int sqlite3VdbeMemTooBig(Mem*);
-SQLITE_PRIVATE int sqlite3VdbeMemCopy(Mem*, const Mem*);
-SQLITE_PRIVATE void sqlite3VdbeMemShallowCopy(Mem*, const Mem*, int);
-SQLITE_PRIVATE void sqlite3VdbeMemMove(Mem*, Mem*);
-SQLITE_PRIVATE int sqlite3VdbeMemNulTerminate(Mem*);
-SQLITE_PRIVATE int sqlite3VdbeMemSetStr(Mem*, const char*, int, u8, void(*)(void*));
-SQLITE_PRIVATE void sqlite3VdbeMemSetInt64(Mem*, i64);
-#ifdef SQLITE_OMIT_FLOATING_POINT
-# define sqlite3VdbeMemSetDouble sqlite3VdbeMemSetInt64
-#else
-SQLITE_PRIVATE   void sqlite3VdbeMemSetDouble(Mem*, double);
-#endif
-SQLITE_PRIVATE void sqlite3VdbeMemSetNull(Mem*);
-SQLITE_PRIVATE void sqlite3VdbeMemSetZeroBlob(Mem*,int);
-SQLITE_PRIVATE void sqlite3VdbeMemSetRowSet(Mem*);
-SQLITE_PRIVATE int sqlite3VdbeMemMakeWriteable(Mem*);
-SQLITE_PRIVATE int sqlite3VdbeMemStringify(Mem*, int);
-SQLITE_PRIVATE i64 sqlite3VdbeIntValue(Mem*);
-SQLITE_PRIVATE int sqlite3VdbeMemIntegerify(Mem*);
-SQLITE_PRIVATE double sqlite3VdbeRealValue(Mem*);
-SQLITE_PRIVATE void sqlite3VdbeIntegerAffinity(Mem*);
-SQLITE_PRIVATE int sqlite3VdbeMemRealify(Mem*);
-SQLITE_PRIVATE int sqlite3VdbeMemNumerify(Mem*);
-SQLITE_PRIVATE int sqlite3VdbeMemFromBtree(BtCursor*,int,int,int,Mem*);
-SQLITE_PRIVATE void sqlite3VdbeMemRelease(Mem *p);
-SQLITE_PRIVATE void sqlite3VdbeMemReleaseExternal(Mem *p);
-SQLITE_PRIVATE int sqlite3VdbeMemFinalize(Mem*, FuncDef*);
-SQLITE_PRIVATE const char *sqlite3OpcodeName(int);
-SQLITE_PRIVATE int sqlite3VdbeMemGrow(Mem *pMem, int n, int preserve);
-SQLITE_PRIVATE int sqlite3VdbeCloseStatement(Vdbe *, int);
-SQLITE_PRIVATE void sqlite3VdbeFrameDelete(VdbeFrame*);
-SQLITE_PRIVATE int sqlite3VdbeFrameRestore(VdbeFrame *);
-SQLITE_PRIVATE void sqlite3VdbeMemStoreType(Mem *pMem);
-
-#ifndef SQLITE_OMIT_FOREIGN_KEY
-SQLITE_PRIVATE int sqlite3VdbeCheckFk(Vdbe *, int);
-#else
-# define sqlite3VdbeCheckFk(p,i) 0
-#endif
-
-#ifndef SQLITE_OMIT_SHARED_CACHE
-SQLITE_PRIVATE void sqlite3VdbeMutexArrayEnter(Vdbe *p);
-#else
-# define sqlite3VdbeMutexArrayEnter(p)
-#endif
-
-SQLITE_PRIVATE int sqlite3VdbeMemTranslate(Mem*, u8);
-#ifdef SQLITE_DEBUG
-SQLITE_PRIVATE   void sqlite3VdbePrintSql(Vdbe*);
-SQLITE_PRIVATE   void sqlite3VdbeMemPrettyPrint(Mem *pMem, char *zBuf);
-#endif
-SQLITE_PRIVATE int sqlite3VdbeMemHandleBom(Mem *pMem);
-
-#ifndef SQLITE_OMIT_INCRBLOB
-SQLITE_PRIVATE   int sqlite3VdbeMemExpandBlob(Mem *);
-#else
-  #define sqlite3VdbeMemExpandBlob(x) SQLITE_OK
-#endif
-
-#endif /* !defined(_VDBEINT_H_) */
-
-/************** End of vdbeInt.h *********************************************/
-/************** Continuing where we left off in utf.c ************************/
 
 #ifndef SQLITE_AMALGAMATION
 /*
@@ -19591,6 +20063,12 @@
 /*
 ** Some systems have stricmp().  Others have strcasecmp().  Because
 ** there is no consistency, we will define our own.
+**
+** IMPLEMENTATION-OF: R-20522-24639 The sqlite3_strnicmp() API allows
+** applications and extensions to compare the contents of two buffers
+** containing UTF-8 strings in a case-independent fashion, using the same
+** definition of case independence that SQLite uses internally when
+** comparing identifiers.
 */
 SQLITE_PRIVATE int sqlite3StrICmp(const char *zLeft, const char *zRight){
   register unsigned char *a, *b;
@@ -21881,7 +22359,7 @@
 
   memset( pFile, 0, sizeof(*pFile) );
 
-  OSTRACE( "OPEN want %d\n", flags ));
+  OSTRACE(( "OPEN want %d\n", flags ));
 
   if( flags & SQLITE_OPEN_READWRITE ){
     ulOpenMode |= OPEN_ACCESS_READWRITE;
@@ -22441,6 +22919,7 @@
   int fileFlags;                      /* Miscellanous flags */
   const char *zPath;                  /* Name of the file */
   unixShm *pShm;                      /* Shared memory segment information */
+  int szChunk;                        /* Configured by FCNTL_CHUNK_SIZE */
 #if SQLITE_ENABLE_LOCKING_STYLE
   int openFlags;                      /* The flags specified at open() */
 #endif
@@ -25199,6 +25678,7 @@
   }
   SimulateIOError(( wrote=(-1), amt=1 ));
   SimulateDiskfullError(( wrote=0, amt=1 ));
+
   if( amt>0 ){
     if( wrote<0 ){
       /* lastErrno set by seekAndWrite */
@@ -25208,6 +25688,7 @@
       return SQLITE_FULL;
     }
   }
+
   return SQLITE_OK;
 }
 
@@ -25409,12 +25890,23 @@
 ** Truncate an open file to a specified size
 */
 static int unixTruncate(sqlite3_file *id, i64 nByte){
+  unixFile *pFile = (unixFile *)id;
   int rc;
-  assert( id );
+  assert( pFile );
   SimulateIOError( return SQLITE_IOERR_TRUNCATE );
-  rc = ftruncate(((unixFile*)id)->h, (off_t)nByte);
+
+  /* If the user has configured a chunk-size for this file, truncate the
+  ** file so that it consists of an integer number of chunks (i.e. the
+  ** actual file size after the operation may be larger than the requested
+  ** size).
+  */
+  if( pFile->szChunk ){
+    nByte = ((nByte + pFile->szChunk - 1)/pFile->szChunk) * pFile->szChunk;
+  }
+
+  rc = ftruncate(pFile->h, (off_t)nByte);
   if( rc ){
-    ((unixFile*)id)->lastErrno = errno;
+    pFile->lastErrno = errno;
     return SQLITE_IOERR_TRUNCATE;
   }else{
 #ifndef NDEBUG
@@ -25425,8 +25917,8 @@
     ** when restoring a database using the backup API from a zero-length
     ** source.
     */
-    if( ((unixFile*)id)->inNormalWrite && nByte==0 ){
-      ((unixFile*)id)->transCntrChng = 1;
+    if( pFile->inNormalWrite && nByte==0 ){
+      pFile->transCntrChng = 1;
     }
 #endif
 
@@ -25469,6 +25961,54 @@
 static int proxyFileControl(sqlite3_file*,int,void*);
 #endif
 
+/* 
+** This function is called to handle the SQLITE_FCNTL_SIZE_HINT 
+** file-control operation.
+**
+** If the user has configured a chunk-size for this file, it could be
+** that the file needs to be extended at this point. Otherwise, the
+** SQLITE_FCNTL_SIZE_HINT operation is a no-op for Unix.
+*/
+static int fcntlSizeHint(unixFile *pFile, i64 nByte){
+  if( pFile->szChunk ){
+    i64 nSize;                    /* Required file size */
+    struct stat buf;              /* Used to hold return values of fstat() */
+   
+    if( fstat(pFile->h, &buf) ) return SQLITE_IOERR_FSTAT;
+
+    nSize = ((nByte+pFile->szChunk-1) / pFile->szChunk) * pFile->szChunk;
+    if( nSize>(i64)buf.st_size ){
+#if defined(HAVE_POSIX_FALLOCATE) && HAVE_POSIX_FALLOCATE
+      if( posix_fallocate(pFile->h, buf.st_size, nSize-buf.st_size) ){
+        return SQLITE_IOERR_WRITE;
+      }
+#else
+      /* If the OS does not have posix_fallocate(), fake it. First use
+      ** ftruncate() to set the file size, then write a single byte to
+      ** the last byte in each block within the extended region. This
+      ** is the same technique used by glibc to implement posix_fallocate()
+      ** on systems that do not have a real fallocate() system call.
+      */
+      int nBlk = buf.st_blksize;  /* File-system block size */
+      i64 iWrite;                 /* Next offset to write to */
+      int nWrite;                 /* Return value from seekAndWrite() */
+
+      if( ftruncate(pFile->h, nSize) ){
+        pFile->lastErrno = errno;
+        return SQLITE_IOERR_TRUNCATE;
+      }
+      iWrite = ((buf.st_size + 2*nBlk - 1)/nBlk)*nBlk-1;
+      do {
+        nWrite = seekAndWrite(pFile, iWrite, "", 1);
+        iWrite += nBlk;
+      } while( nWrite==1 && iWrite<nSize );
+      if( nWrite!=1 ) return SQLITE_IOERR_WRITE;
+#endif
+    }
+  }
+
+  return SQLITE_OK;
+}
 
 /*
 ** Information and control of an open file handle.
@@ -25483,14 +26023,13 @@
       *(int*)pArg = ((unixFile*)id)->lastErrno;
       return SQLITE_OK;
     }
-    case SQLITE_FCNTL_SIZE_HINT: {
-#if 0 /* No performance advantage seen on Linux */
-      sqlite3_int64 szFile = *(sqlite3_int64*)pArg;
-      unixFile *pFile = (unixFile*)id;
-      ftruncate(pFile->h, szFile);
-#endif
+    case SQLITE_FCNTL_CHUNK_SIZE: {
+      ((unixFile*)id)->szChunk = *(int *)pArg;
       return SQLITE_OK;
     }
+    case SQLITE_FCNTL_SIZE_HINT: {
+      return fcntlSizeHint((unixFile *)id, *(i64 *)pArg);
+    }
 #ifndef NDEBUG
     /* The pager calls this method to signal that it has done
     ** a rollback and that the database is therefore unchanged and
@@ -25711,52 +26250,72 @@
 }
 
 /*
-** Open a shared-memory area associated with open database file fd.  
+** Open a shared-memory area associated with open database file pDbFd.  
 ** This particular implementation uses mmapped files.
 **
 ** The file used to implement shared-memory is in the same directory
 ** as the open database file and has the same name as the open database
 ** file with the "-shm" suffix added.  For example, if the database file
 ** is "/home/user1/config.db" then the file that is created and mmapped
-** for shared memory will be called "/home/user1/config.db-shm".  We
-** experimented with using files in /dev/tmp or an some other tmpfs mount.
-** But if a file in a different directory from the database file is used,
-** then differing access permissions or a chroot() might cause two different 
-** processes on the same database to end up using different files for 
-** shared memory - meaning that their memory would not really be shared - 
-** resulting in database corruption.
+** for shared memory will be called "/home/user1/config.db-shm".  
+**
+** Another approach to is to use files in /dev/shm or /dev/tmp or an
+** some other tmpfs mount. But if a file in a different directory
+** from the database file is used, then differing access permissions
+** or a chroot() might cause two different processes on the same
+** database to end up using different files for shared memory - 
+** meaning that their memory would not really be shared - resulting
+** in database corruption.  Nevertheless, this tmpfs file usage
+** can be enabled at compile-time using -DSQLITE_SHM_DIRECTORY="/dev/shm"
+** or the equivalent.  The use of the SQLITE_SHM_DIRECTORY compile-time
+** option results in an incompatible build of SQLite;  builds of SQLite
+** that with differing SQLITE_SHM_DIRECTORY settings attempt to use the
+** same database file at the same time, database corruption will likely
+** result. The SQLITE_SHM_DIRECTORY compile-time option is considered
+** "unsupported" and may go away in a future SQLite release.
 **
 ** When opening a new shared-memory file, if no other instances of that
 ** file are currently open, in this process or in other processes, then
 ** the file must be truncated to zero length or have its header cleared.
 */
-static int unixShmOpen(
-  sqlite3_file *fd      /* The file descriptor of the associated database */
-){
-  struct unixShm *p = 0;             /* The connection to be opened */
-  struct unixShmNode *pShmNode = 0;  /* The underlying mmapped file */
-  int rc;                            /* Result code */
-  struct unixFile *pDbFd;            /* Underlying database file */
-  unixInodeInfo *pInode;             /* The inode of fd */
-  char *zShmFilename;                /* Name of the file used for SHM */
-  int nShmFilename;                  /* Size of the SHM filename in bytes */
+static int unixOpenSharedMemory(unixFile *pDbFd){
+  struct unixShm *p = 0;          /* The connection to be opened */
+  struct unixShmNode *pShmNode;   /* The underlying mmapped file */
+  int rc;                         /* Result code */
+  unixInodeInfo *pInode;          /* The inode of fd */
+  char *zShmFilename;             /* Name of the file used for SHM */
+  int nShmFilename;               /* Size of the SHM filename in bytes */
 
-  /* Allocate space for the new sqlite3_shm object.
-  */
+  /* Allocate space for the new unixShm object. */
   p = sqlite3_malloc( sizeof(*p) );
   if( p==0 ) return SQLITE_NOMEM;
   memset(p, 0, sizeof(*p));
-  pDbFd = (struct unixFile*)fd;
   assert( pDbFd->pShm==0 );
 
-  /* Check to see if a unixShmNode object already exists.  Reuse an existing
-  ** one if present.  Create a new one if necessary.
+  /* Check to see if a unixShmNode object already exists. Reuse an existing
+  ** one if present. Create a new one if necessary.
   */
   unixEnterMutex();
   pInode = pDbFd->pInode;
   pShmNode = pInode->pShmNode;
   if( pShmNode==0 ){
+    struct stat sStat;                 /* fstat() info for database file */
+
+    /* Call fstat() to figure out the permissions on the database file. If
+    ** a new *-shm file is created, an attempt will be made to create it
+    ** with the same permissions. The actual permissions the file is created
+    ** with are subject to the current umask setting.
+    */
+    if( fstat(pDbFd->h, &sStat) ){
+      rc = SQLITE_IOERR_FSTAT;
+      goto shm_open_err;
+    }
+
+#ifdef SQLITE_SHM_DIRECTORY
+    nShmFilename = sizeof(SQLITE_SHM_DIRECTORY) + 30;
+#else
     nShmFilename = 5 + (int)strlen(pDbFd->zPath);
+#endif
     pShmNode = sqlite3_malloc( sizeof(*pShmNode) + nShmFilename );
     if( pShmNode==0 ){
       rc = SQLITE_NOMEM;
@@ -25764,7 +26323,13 @@
     }
     memset(pShmNode, 0, sizeof(*pShmNode));
     zShmFilename = pShmNode->zFilename = (char*)&pShmNode[1];
+#ifdef SQLITE_SHM_DIRECTORY
+    sqlite3_snprintf(nShmFilename, zShmFilename, 
+                     SQLITE_SHM_DIRECTORY "/sqlite-shm-%x-%x",
+                     (u32)sStat.st_ino, (u32)sStat.st_dev);
+#else
     sqlite3_snprintf(nShmFilename, zShmFilename, "%s-shm", pDbFd->zPath);
+#endif
     pShmNode->h = -1;
     pDbFd->pInode->pShmNode = pShmNode;
     pShmNode->pInode = pDbFd->pInode;
@@ -25774,7 +26339,7 @@
       goto shm_open_err;
     }
 
-    pShmNode->h = open(zShmFilename, O_RDWR|O_CREAT, 0664);
+    pShmNode->h = open(zShmFilename, O_RDWR|O_CREAT, (sStat.st_mode & 0777));
     if( pShmNode->h<0 ){
       rc = SQLITE_CANTOPEN_BKPT;
       goto shm_open_err;
@@ -25797,14 +26362,24 @@
 
   /* Make the new connection a child of the unixShmNode */
   p->pShmNode = pShmNode;
-  p->pNext = pShmNode->pFirst;
 #ifdef SQLITE_DEBUG
   p->id = pShmNode->nextShmId++;
 #endif
-  pShmNode->pFirst = p;
   pShmNode->nRef++;
   pDbFd->pShm = p;
   unixLeaveMutex();
+
+  /* The reference count on pShmNode has already been incremented under
+  ** the cover of the unixEnterMutex() mutex and the pointer from the
+  ** new (struct unixShm) object to the pShmNode has been set. All that is
+  ** left to do is to link the new object into the linked list starting
+  ** at pShmNode->pFirst. This must be done while holding the pShmNode->mutex 
+  ** mutex.
+  */
+  sqlite3_mutex_enter(pShmNode->mutex);
+  p->pNext = pShmNode->pFirst;
+  pShmNode->pFirst = p;
+  sqlite3_mutex_leave(pShmNode->mutex);
   return SQLITE_OK;
 
   /* Jump here on any error */
@@ -25816,49 +26391,107 @@
 }
 
 /*
-** Close a connection to shared-memory.  Delete the underlying 
-** storage if deleteFlag is true.
+** This function is called to obtain a pointer to region iRegion of the 
+** shared-memory associated with the database file fd. Shared-memory regions 
+** are numbered starting from zero. Each shared-memory region is szRegion 
+** bytes in size.
+**
+** If an error occurs, an error code is returned and *pp is set to NULL.
+**
+** Otherwise, if the bExtend parameter is 0 and the requested shared-memory
+** region has not been allocated (by any client, including one running in a
+** separate process), then *pp is set to NULL and SQLITE_OK returned. If 
+** bExtend is non-zero and the requested shared-memory region has not yet 
+** been allocated, it is allocated by this function.
+**
+** If the shared-memory region has already been allocated or is allocated by
+** this call as described above, then it is mapped into this processes 
+** address space (if it is not already), *pp is set to point to the mapped 
+** memory and SQLITE_OK returned.
 */
-static int unixShmClose(
-  sqlite3_file *fd,          /* The underlying database file */
-  int deleteFlag             /* Delete shared-memory if true */
+static int unixShmMap(
+  sqlite3_file *fd,               /* Handle open on database file */
+  int iRegion,                    /* Region to retrieve */
+  int szRegion,                   /* Size of regions */
+  int bExtend,                    /* True to extend file if necessary */
+  void volatile **pp              /* OUT: Mapped memory */
 ){
-  unixShm *p;            /* The connection to be closed */
-  unixShmNode *pShmNode; /* The underlying shared-memory file */
-  unixShm **pp;          /* For looping over sibling connections */
-  unixFile *pDbFd;       /* The underlying database file */
+  unixFile *pDbFd = (unixFile*)fd;
+  unixShm *p;
+  unixShmNode *pShmNode;
+  int rc = SQLITE_OK;
 
-  pDbFd = (unixFile*)fd;
-  p = pDbFd->pShm;
-  if( p==0 ) return SQLITE_OK;
-  pShmNode = p->pShmNode;
-
-  assert( pShmNode==pDbFd->pInode->pShmNode );
-  assert( pShmNode->pInode==pDbFd->pInode );
-
-  /* Remove connection p from the set of connections associated
-  ** with pShmNode */
-  sqlite3_mutex_enter(pShmNode->mutex);
-  for(pp=&pShmNode->pFirst; (*pp)!=p; pp = &(*pp)->pNext){}
-  *pp = p->pNext;
-
-  /* Free the connection p */
-  sqlite3_free(p);
-  pDbFd->pShm = 0;
-  sqlite3_mutex_leave(pShmNode->mutex);
-
-  /* If pShmNode->nRef has reached 0, then close the underlying
-  ** shared-memory file, too */
-  unixEnterMutex();
-  assert( pShmNode->nRef>0 );
-  pShmNode->nRef--;
-  if( pShmNode->nRef==0 ){
-    if( deleteFlag ) unlink(pShmNode->zFilename);
-    unixShmPurge(pDbFd);
+  /* If the shared-memory file has not yet been opened, open it now. */
+  if( pDbFd->pShm==0 ){
+    rc = unixOpenSharedMemory(pDbFd);
+    if( rc!=SQLITE_OK ) return rc;
   }
-  unixLeaveMutex();
 
-  return SQLITE_OK;
+  p = pDbFd->pShm;
+  pShmNode = p->pShmNode;
+  sqlite3_mutex_enter(pShmNode->mutex);
+  assert( szRegion==pShmNode->szRegion || pShmNode->nRegion==0 );
+
+  if( pShmNode->nRegion<=iRegion ){
+    char **apNew;                      /* New apRegion[] array */
+    int nByte = (iRegion+1)*szRegion;  /* Minimum required file size */
+    struct stat sStat;                 /* Used by fstat() */
+
+    pShmNode->szRegion = szRegion;
+
+    /* The requested region is not mapped into this processes address space.
+    ** Check to see if it has been allocated (i.e. if the wal-index file is
+    ** large enough to contain the requested region).
+    */
+    if( fstat(pShmNode->h, &sStat) ){
+      rc = SQLITE_IOERR_SHMSIZE;
+      goto shmpage_out;
+    }
+
+    if( sStat.st_size<nByte ){
+      /* The requested memory region does not exist. If bExtend is set to
+      ** false, exit early. *pp will be set to NULL and SQLITE_OK returned.
+      **
+      ** Alternatively, if bExtend is true, use ftruncate() to allocate
+      ** the requested memory region.
+      */
+      if( !bExtend ) goto shmpage_out;
+      if( ftruncate(pShmNode->h, nByte) ){
+        rc = SQLITE_IOERR_SHMSIZE;
+        goto shmpage_out;
+      }
+    }
+
+    /* Map the requested memory region into this processes address space. */
+    apNew = (char **)sqlite3_realloc(
+        pShmNode->apRegion, (iRegion+1)*sizeof(char *)
+    );
+    if( !apNew ){
+      rc = SQLITE_IOERR_NOMEM;
+      goto shmpage_out;
+    }
+    pShmNode->apRegion = apNew;
+    while(pShmNode->nRegion<=iRegion){
+      void *pMem = mmap(0, szRegion, PROT_READ|PROT_WRITE, 
+          MAP_SHARED, pShmNode->h, pShmNode->nRegion*szRegion
+      );
+      if( pMem==MAP_FAILED ){
+        rc = SQLITE_IOERR;
+        goto shmpage_out;
+      }
+      pShmNode->apRegion[pShmNode->nRegion] = pMem;
+      pShmNode->nRegion++;
+    }
+  }
+
+shmpage_out:
+  if( pShmNode->nRegion>iRegion ){
+    *pp = pShmNode->apRegion[iRegion];
+  }else{
+    *pp = 0;
+  }
+  sqlite3_mutex_leave(pShmNode->mutex);
+  return rc;
 }
 
 /*
@@ -25988,107 +26621,60 @@
 }
 
 /*
-** This function is called to obtain a pointer to region iRegion of the 
-** shared-memory associated with the database file fd. Shared-memory regions 
-** are numbered starting from zero. Each shared-memory region is szRegion 
-** bytes in size.
+** Close a connection to shared-memory.  Delete the underlying 
+** storage if deleteFlag is true.
 **
-** If an error occurs, an error code is returned and *pp is set to NULL.
-**
-** Otherwise, if the isWrite parameter is 0 and the requested shared-memory
-** region has not been allocated (by any client, including one running in a
-** separate process), then *pp is set to NULL and SQLITE_OK returned. If 
-** isWrite is non-zero and the requested shared-memory region has not yet 
-** been allocated, it is allocated by this function.
-**
-** If the shared-memory region has already been allocated or is allocated by
-** this call as described above, then it is mapped into this processes 
-** address space (if it is not already), *pp is set to point to the mapped 
-** memory and SQLITE_OK returned.
+** If there is no shared memory associated with the connection then this
+** routine is a harmless no-op.
 */
-static int unixShmMap(
-  sqlite3_file *fd,               /* Handle open on database file */
-  int iRegion,                    /* Region to retrieve */
-  int szRegion,                   /* Size of regions */
-  int isWrite,                    /* True to extend file if necessary */
-  void volatile **pp              /* OUT: Mapped memory */
+static int unixShmUnmap(
+  sqlite3_file *fd,               /* The underlying database file */
+  int deleteFlag                  /* Delete shared-memory if true */
 ){
-  unixFile *pDbFd = (unixFile*)fd;
-  unixShm *p = pDbFd->pShm;
-  unixShmNode *pShmNode = p->pShmNode;
-  int rc = SQLITE_OK;
+  unixShm *p;                     /* The connection to be closed */
+  unixShmNode *pShmNode;          /* The underlying shared-memory file */
+  unixShm **pp;                   /* For looping over sibling connections */
+  unixFile *pDbFd;                /* The underlying database file */
 
+  pDbFd = (unixFile*)fd;
+  p = pDbFd->pShm;
+  if( p==0 ) return SQLITE_OK;
+  pShmNode = p->pShmNode;
+
+  assert( pShmNode==pDbFd->pInode->pShmNode );
+  assert( pShmNode->pInode==pDbFd->pInode );
+
+  /* Remove connection p from the set of connections associated
+  ** with pShmNode */
   sqlite3_mutex_enter(pShmNode->mutex);
-  assert( szRegion==pShmNode->szRegion || pShmNode->nRegion==0 );
+  for(pp=&pShmNode->pFirst; (*pp)!=p; pp = &(*pp)->pNext){}
+  *pp = p->pNext;
 
-  if( pShmNode->nRegion<=iRegion ){
-    char **apNew;                      /* New apRegion[] array */
-    int nByte = (iRegion+1)*szRegion;  /* Minimum required file size */
-    struct stat sStat;                 /* Used by fstat() */
-
-    pShmNode->szRegion = szRegion;
-
-    /* The requested region is not mapped into this processes address space.
-    ** Check to see if it has been allocated (i.e. if the wal-index file is
-    ** large enough to contain the requested region).
-    */
-    if( fstat(pShmNode->h, &sStat) ){
-      rc = SQLITE_IOERR_SHMSIZE;
-      goto shmpage_out;
-    }
-
-    if( sStat.st_size<nByte ){
-      /* The requested memory region does not exist. If isWrite is set to
-      ** zero, exit early. *pp will be set to NULL and SQLITE_OK returned.
-      **
-      ** Alternatively, if isWrite is non-zero, use ftruncate() to allocate
-      ** the requested memory region.
-      */
-      if( !isWrite ) goto shmpage_out;
-      if( ftruncate(pShmNode->h, nByte) ){
-        rc = SQLITE_IOERR_SHMSIZE;
-        goto shmpage_out;
-      }  
-    }
-
-    /* Map the requested memory region into this processes address space. */
-    apNew = (char **)sqlite3_realloc(
-        pShmNode->apRegion, (iRegion+1)*sizeof(char *)
-    );
-    if( !apNew ){
-      rc = SQLITE_IOERR_NOMEM;
-      goto shmpage_out;
-    }
-    pShmNode->apRegion = apNew;
-    while(pShmNode->nRegion<=iRegion){
-      void *pMem = mmap(0, szRegion, PROT_READ|PROT_WRITE, 
-          MAP_SHARED, pShmNode->h, iRegion*szRegion
-      );
-      if( pMem==MAP_FAILED ){
-        rc = SQLITE_IOERR;
-        goto shmpage_out;
-      }
-      pShmNode->apRegion[pShmNode->nRegion] = pMem;
-      pShmNode->nRegion++;
-    }
-  }
-
-shmpage_out:
-  if( pShmNode->nRegion>iRegion ){
-    *pp = pShmNode->apRegion[iRegion];
-  }else{
-    *pp = 0;
-  }
+  /* Free the connection p */
+  sqlite3_free(p);
+  pDbFd->pShm = 0;
   sqlite3_mutex_leave(pShmNode->mutex);
-  return rc;
+
+  /* If pShmNode->nRef has reached 0, then close the underlying
+  ** shared-memory file, too */
+  unixEnterMutex();
+  assert( pShmNode->nRef>0 );
+  pShmNode->nRef--;
+  if( pShmNode->nRef==0 ){
+    if( deleteFlag ) unlink(pShmNode->zFilename);
+    unixShmPurge(pDbFd);
+  }
+  unixLeaveMutex();
+
+  return SQLITE_OK;
 }
 
+
 #else
-# define unixShmOpen    0
-# define unixShmLock    0
 # define unixShmMap     0
+# define unixShmLock    0
 # define unixShmBarrier 0
-# define unixShmClose   0
+# define unixShmUnmap   0
 #endif /* #ifndef SQLITE_OMIT_WAL */
 
 /*
@@ -26146,11 +26732,10 @@
    unixFileControl,            /* xFileControl */                            \
    unixSectorSize,             /* xSectorSize */                             \
    unixDeviceCharacteristics,  /* xDeviceCapabilities */                     \
-   unixShmOpen,                /* xShmOpen */                                \
-   unixShmLock,                /* xShmLock */                                \
    unixShmMap,                 /* xShmMap */                                 \
+   unixShmLock,                /* xShmLock */                                \
    unixShmBarrier,             /* xShmBarrier */                             \
-   unixShmClose                /* xShmClose */                               \
+   unixShmUnmap                /* xShmUnmap */                               \
 };                                                                           \
 static const sqlite3_io_methods *FINDER##Impl(const char *z, unixFile *p){   \
   UNUSED_PARAMETER(z); UNUSED_PARAMETER(p);                                  \
@@ -26167,7 +26752,7 @@
 IOMETHODS(
   posixIoFinder,            /* Finder function name */
   posixIoMethods,           /* sqlite3_io_methods object name */
-  2,                        /* ShmOpen is enabled */
+  2,                        /* shared memory is enabled */
   unixClose,                /* xClose method */
   unixLock,                 /* xLock method */
   unixUnlock,               /* xUnlock method */
@@ -26176,7 +26761,7 @@
 IOMETHODS(
   nolockIoFinder,           /* Finder function name */
   nolockIoMethods,          /* sqlite3_io_methods object name */
-  1,                        /* ShmOpen is disabled */
+  1,                        /* shared memory is disabled */
   nolockClose,              /* xClose method */
   nolockLock,               /* xLock method */
   nolockUnlock,             /* xUnlock method */
@@ -26185,7 +26770,7 @@
 IOMETHODS(
   dotlockIoFinder,          /* Finder function name */
   dotlockIoMethods,         /* sqlite3_io_methods object name */
-  1,                        /* ShmOpen is disabled */
+  1,                        /* shared memory is disabled */
   dotlockClose,             /* xClose method */
   dotlockLock,              /* xLock method */
   dotlockUnlock,            /* xUnlock method */
@@ -26196,7 +26781,7 @@
 IOMETHODS(
   flockIoFinder,            /* Finder function name */
   flockIoMethods,           /* sqlite3_io_methods object name */
-  1,                        /* ShmOpen is disabled */
+  1,                        /* shared memory is disabled */
   flockClose,               /* xClose method */
   flockLock,                /* xLock method */
   flockUnlock,              /* xUnlock method */
@@ -26208,7 +26793,7 @@
 IOMETHODS(
   semIoFinder,              /* Finder function name */
   semIoMethods,             /* sqlite3_io_methods object name */
-  1,                        /* ShmOpen is disabled */
+  1,                        /* shared memory is disabled */
   semClose,                 /* xClose method */
   semLock,                  /* xLock method */
   semUnlock,                /* xUnlock method */
@@ -26220,7 +26805,7 @@
 IOMETHODS(
   afpIoFinder,              /* Finder function name */
   afpIoMethods,             /* sqlite3_io_methods object name */
-  1,                        /* ShmOpen is disabled */
+  1,                        /* shared memory is disabled */
   afpClose,                 /* xClose method */
   afpLock,                  /* xLock method */
   afpUnlock,                /* xUnlock method */
@@ -26245,7 +26830,7 @@
 IOMETHODS(
   proxyIoFinder,            /* Finder function name */
   proxyIoMethods,           /* sqlite3_io_methods object name */
-  1,                        /* ShmOpen is disabled */
+  1,                        /* shared memory is disabled */
   proxyClose,               /* xClose method */
   proxyLock,                /* xLock method */
   proxyUnlock,              /* xUnlock method */
@@ -26258,7 +26843,7 @@
 IOMETHODS(
   nfsIoFinder,               /* Finder function name */
   nfsIoMethods,              /* sqlite3_io_methods object name */
-  1,                         /* ShmOpen is disabled */
+  1,                         /* shared memory is disabled */
   unixClose,                 /* xClose method */
   unixLock,                  /* xLock method */
   nfsUnlock,                 /* xUnlock method */
@@ -26722,6 +27307,51 @@
 }
 
 /*
+** This function is called by unixOpen() to determine the unix permissions
+** to create new files with. If no error occurs, then SQLITE_OK is returned
+** and a value suitable for passing as the third argument to open(2) is
+** written to *pMode. If an IO error occurs, an SQLite error code is 
+** returned and the value of *pMode is not modified.
+**
+** If the file being opened is a temporary file, it is always created with
+** the octal permissions 0600 (read/writable by owner only). If the file
+** is a database or master journal file, it is created with the permissions 
+** mask SQLITE_DEFAULT_FILE_PERMISSIONS.
+**
+** Finally, if the file being opened is a WAL or regular journal file, then 
+** this function queries the file-system for the permissions on the 
+** corresponding database file and sets *pMode to this value. Whenever 
+** possible, WAL and journal files are created using the same permissions 
+** as the associated database file.
+*/
+static int findCreateFileMode(
+  const char *zPath,              /* Path of file (possibly) being created */
+  int flags,                      /* Flags passed as 4th argument to xOpen() */
+  mode_t *pMode                   /* OUT: Permissions to open file with */
+){
+  int rc = SQLITE_OK;             /* Return Code */
+  if( flags & (SQLITE_OPEN_WAL|SQLITE_OPEN_MAIN_JOURNAL) ){
+    char zDb[MAX_PATHNAME+1];     /* Database file path */
+    int nDb;                      /* Number of valid bytes in zDb */
+    struct stat sStat;            /* Output of stat() on database file */
+
+    nDb = sqlite3Strlen30(zPath) - ((flags & SQLITE_OPEN_WAL) ? 4 : 8);
+    memcpy(zDb, zPath, nDb);
+    zDb[nDb] = '\0';
+    if( 0==stat(zDb, &sStat) ){
+      *pMode = sStat.st_mode & 0777;
+    }else{
+      rc = SQLITE_IOERR_FSTAT;
+    }
+  }else if( flags & SQLITE_OPEN_DELETEONCLOSE ){
+    *pMode = 0600;
+  }else{
+    *pMode = SQLITE_DEFAULT_FILE_PERMISSIONS;
+  }
+  return rc;
+}
+
+/*
 ** Open the file zPath.
 ** 
 ** Previously, the SQLite OS layer used three functions in place of this
@@ -26771,9 +27401,11 @@
   ** a file-descriptor on the directory too. The first time unixSync()
   ** is called the directory file descriptor will be fsync()ed and close()d.
   */
-  int isOpenDirectory = (isCreate && 
-      (eType==SQLITE_OPEN_MASTER_JOURNAL || eType==SQLITE_OPEN_MAIN_JOURNAL)
-  );
+  int isOpenDirectory = (isCreate && (
+        eType==SQLITE_OPEN_MASTER_JOURNAL 
+     || eType==SQLITE_OPEN_MAIN_JOURNAL 
+     || eType==SQLITE_OPEN_WAL
+  ));
 
   /* If argument zPath is a NULL pointer, this function is required to open
   ** a temporary file. Use this buffer to store the file name in.
@@ -26793,17 +27425,18 @@
   assert(isExclusive==0 || isCreate);
   assert(isDelete==0 || isCreate);
 
-  /* The main DB, main journal, and master journal are never automatically
-  ** deleted. Nor are they ever temporary files.  */
+  /* The main DB, main journal, WAL file and master journal are never 
+  ** automatically deleted. Nor are they ever temporary files.  */
   assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_DB );
   assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_JOURNAL );
   assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MASTER_JOURNAL );
+  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_WAL );
 
   /* Assert that the upper layer has set one of the "file-type" flags. */
   assert( eType==SQLITE_OPEN_MAIN_DB      || eType==SQLITE_OPEN_TEMP_DB 
        || eType==SQLITE_OPEN_MAIN_JOURNAL || eType==SQLITE_OPEN_TEMP_JOURNAL 
        || eType==SQLITE_OPEN_SUBJOURNAL   || eType==SQLITE_OPEN_MASTER_JOURNAL 
-       || eType==SQLITE_OPEN_TRANSIENT_DB
+       || eType==SQLITE_OPEN_TRANSIENT_DB || eType==SQLITE_OPEN_WAL
   );
 
   memset(p, 0, sizeof(unixFile));
@@ -26841,7 +27474,13 @@
   openFlags |= (O_LARGEFILE|O_BINARY);
 
   if( fd<0 ){
-    mode_t openMode = (isDelete?0600:SQLITE_DEFAULT_FILE_PERMISSIONS);
+    mode_t openMode;              /* Permissions to create file with */
+    rc = findCreateFileMode(zName, flags, &openMode);
+    if( rc!=SQLITE_OK ){
+      assert( !p->pUnused );
+      assert( eType==SQLITE_OPEN_WAL || eType==SQLITE_OPEN_MAIN_JOURNAL );
+      return rc;
+    }
     fd = open(zName, openFlags, openMode);
     OSTRACE(("OPENX   %-3d %s 0%o\n", fd, zName, openFlags));
     if( fd<0 && errno!=EISDIR && isReadWrite && !isExclusive ){
@@ -26984,7 +27623,9 @@
   int rc = SQLITE_OK;
   UNUSED_PARAMETER(NotUsed);
   SimulateIOError(return SQLITE_IOERR_DELETE);
-  unlink(zPath);
+  if( unlink(zPath)==(-1) && errno!=ENOENT ){
+    return SQLITE_IOERR_DELETE;
+  }
 #ifndef SQLITE_DISABLE_DIRSYNC
   if( dirSync ){
     int fd;
@@ -27655,6 +28296,8 @@
   
   assert(PROXY_HOSTIDLEN == sizeof(uuid_t));
   memset(pHostID, 0, PROXY_HOSTIDLEN);
+#if defined(__MAX_OS_X_VERSION_MIN_REQUIRED)\
+               && __MAC_OS_X_VERSION_MIN_REQUIRED<1050
   if( gethostuuid(pHostID, &timeout) ){
     int err = errno;
     if( pError ){
@@ -27662,6 +28305,7 @@
     }
     return SQLITE_IOERR;
   }
+#endif
 #ifdef SQLITE_TEST
   /* simulate multiple hosts by creating unique hostid file paths */
   if( sqlite3_hostid_num != 0){
@@ -28252,7 +28896,7 @@
       pCtx->conchFile->pMethod->xClose((sqlite3_file *)pCtx->conchFile);
       sqlite3_free(pCtx->conchFile);
     }
-    sqlite3_free(pCtx->lockProxyPath);
+    sqlite3DbFree(0, pCtx->lockProxyPath);
     sqlite3_free(pCtx->conchFilePath); 
     sqlite3_free(pCtx);
   }
@@ -28443,9 +29087,9 @@
       if( rc ) return rc;
       sqlite3_free(conchFile);
     }
-    sqlite3_free(pCtx->lockProxyPath);
+    sqlite3DbFree(0, pCtx->lockProxyPath);
     sqlite3_free(pCtx->conchFilePath);
-    sqlite3_free(pCtx->dbPath);
+    sqlite3DbFree(0, pCtx->dbPath);
     /* restore the original locking context and pMethod then close it */
     pFile->lockingContext = pCtx->oldLockingContext;
     pFile->pMethod = pCtx->pOldMethod;
@@ -28891,6 +29535,7 @@
   DWORD sectorSize;       /* Sector size of the device file is on */
   winShm *pShm;           /* Instance of shared memory on this file */
   const char *zPath;      /* Full pathname of this file */
+  int szChunk;            /* Chunk size configured by FCNTL_CHUNK_SIZE */
 #if SQLITE_OS_WINCE
   WCHAR *zDeleteOnClose;  /* Name of file to delete when closing */
   HANDLE hMutex;          /* Mutex used to control access to shared lock */  
@@ -29403,6 +30048,42 @@
 ******************************************************************************/
 
 /*
+** Some microsoft compilers lack this definition.
+*/
+#ifndef INVALID_SET_FILE_POINTER
+# define INVALID_SET_FILE_POINTER ((DWORD)-1)
+#endif
+
+/*
+** Move the current position of the file handle passed as the first 
+** argument to offset iOffset within the file. If successful, return 0. 
+** Otherwise, set pFile->lastErrno and return non-zero.
+*/
+static int seekWinFile(winFile *pFile, sqlite3_int64 iOffset){
+  LONG upperBits;                 /* Most sig. 32 bits of new offset */
+  LONG lowerBits;                 /* Least sig. 32 bits of new offset */
+  DWORD dwRet;                    /* Value returned by SetFilePointer() */
+
+  upperBits = (LONG)((iOffset>>32) & 0x7fffffff);
+  lowerBits = (LONG)(iOffset & 0xffffffff);
+
+  /* API oddity: If successful, SetFilePointer() returns a dword 
+  ** containing the lower 32-bits of the new file-offset. Or, if it fails,
+  ** it returns INVALID_SET_FILE_POINTER. However according to MSDN, 
+  ** INVALID_SET_FILE_POINTER may also be a valid new offset. So to determine 
+  ** whether an error has actually occured, it is also necessary to call 
+  ** GetLastError().
+  */
+  dwRet = SetFilePointer(pFile->h, lowerBits, &upperBits, FILE_BEGIN);
+  if( (dwRet==INVALID_SET_FILE_POINTER && GetLastError()!=NO_ERROR) ){
+    pFile->lastErrno = GetLastError();
+    return 1;
+  }
+
+  return 0;
+}
+
+/*
 ** Close a file.
 **
 ** It is reported that an attempt to close a handle might sometimes
@@ -29422,6 +30103,7 @@
   OSTRACE(("CLOSE %d\n", pFile->h));
   do{
     rc = CloseHandle(pFile->h);
+    /* SimulateIOError( rc=0; cnt=MX_CLOSE_ATTEMPT; ); */
   }while( rc==0 && ++cnt < MX_CLOSE_ATTEMPT && (Sleep(100), 1) );
 #if SQLITE_OS_WINCE
 #define WINCE_DELETION_ATTEMPTS 3
@@ -29444,13 +30126,6 @@
 }
 
 /*
-** Some microsoft compilers lack this definition.
-*/
-#ifndef INVALID_SET_FILE_POINTER
-# define INVALID_SET_FILE_POINTER ((DWORD)-1)
-#endif
-
-/*
 ** Read data from a file into a buffer.  Return SQLITE_OK if all
 ** bytes were read successfully and SQLITE_IOERR if anything goes
 ** wrong.
@@ -29461,32 +30136,27 @@
   int amt,                   /* Number of bytes to read */
   sqlite3_int64 offset       /* Begin reading at this offset */
 ){
-  LONG upperBits = (LONG)((offset>>32) & 0x7fffffff);
-  LONG lowerBits = (LONG)(offset & 0xffffffff);
-  DWORD rc;
-  winFile *pFile = (winFile*)id;
-  DWORD error;
-  DWORD got;
+  winFile *pFile = (winFile*)id;  /* file handle */
+  DWORD nRead;                    /* Number of bytes actually read from file */
 
   assert( id!=0 );
   SimulateIOError(return SQLITE_IOERR_READ);
   OSTRACE(("READ %d lock=%d\n", pFile->h, pFile->locktype));
-  rc = SetFilePointer(pFile->h, lowerBits, &upperBits, FILE_BEGIN);
-  if( rc==INVALID_SET_FILE_POINTER && (error=GetLastError())!=NO_ERROR ){
-    pFile->lastErrno = error;
+
+  if( seekWinFile(pFile, offset) ){
     return SQLITE_FULL;
   }
-  if( !ReadFile(pFile->h, pBuf, amt, &got, 0) ){
+  if( !ReadFile(pFile->h, pBuf, amt, &nRead, 0) ){
     pFile->lastErrno = GetLastError();
     return SQLITE_IOERR_READ;
   }
-  if( got==(DWORD)amt ){
-    return SQLITE_OK;
-  }else{
+  if( nRead<(DWORD)amt ){
     /* Unread parts of the buffer must be zero-filled */
-    memset(&((char*)pBuf)[got], 0, amt-got);
+    memset(&((char*)pBuf)[nRead], 0, amt-nRead);
     return SQLITE_IOERR_SHORT_READ;
   }
+
+  return SQLITE_OK;
 }
 
 /*
@@ -29494,47 +30164,42 @@
 ** or some other error code on failure.
 */
 static int winWrite(
-  sqlite3_file *id,         /* File to write into */
-  const void *pBuf,         /* The bytes to be written */
-  int amt,                  /* Number of bytes to write */
-  sqlite3_int64 offset      /* Offset into the file to begin writing at */
+  sqlite3_file *id,               /* File to write into */
+  const void *pBuf,               /* The bytes to be written */
+  int amt,                        /* Number of bytes to write */
+  sqlite3_int64 offset            /* Offset into the file to begin writing at */
 ){
-  LONG upperBits = (LONG)((offset>>32) & 0x7fffffff);
-  LONG lowerBits = (LONG)(offset & 0xffffffff);
-  DWORD rc;
-  winFile *pFile = (winFile*)id;
-  DWORD error;
-  DWORD wrote = 0;
+  int rc;                         /* True if error has occured, else false */
+  winFile *pFile = (winFile*)id;  /* File handle */
 
-  assert( id!=0 );
+  assert( amt>0 );
+  assert( pFile );
   SimulateIOError(return SQLITE_IOERR_WRITE);
   SimulateDiskfullError(return SQLITE_FULL);
+
   OSTRACE(("WRITE %d lock=%d\n", pFile->h, pFile->locktype));
-  rc = SetFilePointer(pFile->h, lowerBits, &upperBits, FILE_BEGIN);
-  if( rc==INVALID_SET_FILE_POINTER && (error=GetLastError())!=NO_ERROR ){
-    pFile->lastErrno = error;
-    if( pFile->lastErrno==ERROR_HANDLE_DISK_FULL ){
-      return SQLITE_FULL;
-    }else{
-      return SQLITE_IOERR_WRITE;
+
+  rc = seekWinFile(pFile, offset);
+  if( rc==0 ){
+    u8 *aRem = (u8 *)pBuf;        /* Data yet to be written */
+    int nRem = amt;               /* Number of bytes yet to be written */
+    DWORD nWrite;                 /* Bytes written by each WriteFile() call */
+
+    while( nRem>0 && WriteFile(pFile->h, aRem, nRem, &nWrite, 0) && nWrite>0 ){
+      aRem += nWrite;
+      nRem -= nWrite;
+    }
+    if( nRem>0 ){
+      pFile->lastErrno = GetLastError();
+      rc = 1;
     }
   }
-  assert( amt>0 );
-  while(
-     amt>0
-     && (rc = WriteFile(pFile->h, pBuf, amt, &wrote, 0))!=0
-     && wrote>0
-  ){
-    amt -= wrote;
-    pBuf = &((char*)pBuf)[wrote];
-  }
-  if( !rc || amt>(int)wrote ){
-    pFile->lastErrno = GetLastError();
+
+  if( rc ){
     if( pFile->lastErrno==ERROR_HANDLE_DISK_FULL ){
       return SQLITE_FULL;
-    }else{
-      return SQLITE_IOERR_WRITE;
     }
+    return SQLITE_IOERR_WRITE;
   }
   return SQLITE_OK;
 }
@@ -29543,26 +30208,32 @@
 ** Truncate an open file to a specified size
 */
 static int winTruncate(sqlite3_file *id, sqlite3_int64 nByte){
-  LONG upperBits = (LONG)((nByte>>32) & 0x7fffffff);
-  LONG lowerBits = (LONG)(nByte & 0xffffffff);
-  DWORD dwRet;
-  winFile *pFile = (winFile*)id;
-  DWORD error;
-  int rc = SQLITE_OK;
+  winFile *pFile = (winFile*)id;  /* File handle object */
+  int rc = SQLITE_OK;             /* Return code for this function */
 
-  assert( id!=0 );
+  assert( pFile );
+
   OSTRACE(("TRUNCATE %d %lld\n", pFile->h, nByte));
   SimulateIOError(return SQLITE_IOERR_TRUNCATE);
-  dwRet = SetFilePointer(pFile->h, lowerBits, &upperBits, FILE_BEGIN);
-  if( dwRet==INVALID_SET_FILE_POINTER && (error=GetLastError())!=NO_ERROR ){
-    pFile->lastErrno = error;
+
+  /* If the user has configured a chunk-size for this file, truncate the
+  ** file so that it consists of an integer number of chunks (i.e. the
+  ** actual file size after the operation may be larger than the requested
+  ** size).
+  */
+  if( pFile->szChunk ){
+    nByte = ((nByte + pFile->szChunk - 1)/pFile->szChunk) * pFile->szChunk;
+  }
+
+  /* SetEndOfFile() returns non-zero when successful, or zero when it fails. */
+  if( seekWinFile(pFile, nByte) ){
     rc = SQLITE_IOERR_TRUNCATE;
-  /* SetEndOfFile will fail if nByte is negative */
-  }else if( !SetEndOfFile(pFile->h) ){
+  }else if( 0==SetEndOfFile(pFile->h) ){
     pFile->lastErrno = GetLastError();
     rc = SQLITE_IOERR_TRUNCATE;
   }
-  OSTRACE(("TRUNCATE %d %lld %s\n", pFile->h, nByte, rc==SQLITE_OK ? "ok" : "failed"));
+
+  OSTRACE(("TRUNCATE %d %lld %s\n", pFile->h, nByte, rc ? "failed" : "ok"));
   return rc;
 }
 
@@ -29579,14 +30250,20 @@
 ** Make sure all writes to a particular file are committed to disk.
 */
 static int winSync(sqlite3_file *id, int flags){
-#ifndef SQLITE_NO_SYNC
+#if !defined(NDEBUG) || !defined(SQLITE_NO_SYNC) || defined(SQLITE_DEBUG)
   winFile *pFile = (winFile*)id;
-
-  assert( id!=0 );
-  OSTRACE(("SYNC %d lock=%d\n", pFile->h, pFile->locktype));
 #else
   UNUSED_PARAMETER(id);
 #endif
+
+  assert( pFile );
+  /* Check that one of SQLITE_SYNC_NORMAL or FULL was passed */
+  assert((flags&0x0F)==SQLITE_SYNC_NORMAL
+      || (flags&0x0F)==SQLITE_SYNC_FULL
+  );
+
+  OSTRACE(("SYNC %d lock=%d\n", pFile->h, pFile->locktype));
+
 #ifndef SQLITE_TEST
   UNUSED_PARAMETER(flags);
 #else
@@ -29595,11 +30272,18 @@
   }
   sqlite3_sync_count++;
 #endif
+
+  /* Unix cannot, but some systems may return SQLITE_FULL from here. This
+  ** line is to test that doing so does not cause any problems.
+  */
+  SimulateDiskfullError( return SQLITE_FULL );
+  SimulateIOError( return SQLITE_IOERR; );
+
   /* If we compiled with the SQLITE_NO_SYNC flag, then syncing is a
   ** no-op
   */
 #ifdef SQLITE_NO_SYNC
-    return SQLITE_OK;
+  return SQLITE_OK;
 #else
   if( FlushFileBuffers(pFile->h) ){
     return SQLITE_OK;
@@ -29842,6 +30526,8 @@
   int rc;
   winFile *pFile = (winFile*)id;
 
+  SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
+
   assert( id!=0 );
   if( pFile->locktype>=RESERVED_LOCK ){
     rc = 1;
@@ -29912,9 +30598,15 @@
       *(int*)pArg = (int)((winFile*)id)->lastErrno;
       return SQLITE_OK;
     }
+    case SQLITE_FCNTL_CHUNK_SIZE: {
+      ((winFile*)id)->szChunk = *(int *)pArg;
+      return SQLITE_OK;
+    }
     case SQLITE_FCNTL_SIZE_HINT: {
       sqlite3_int64 sz = *(sqlite3_int64*)pArg;
+      SimulateIOErrorBenign(1);
       winTruncate(id, sz);
+      SimulateIOErrorBenign(0);
       return SQLITE_OK;
     }
   }
@@ -29944,13 +30636,16 @@
   return SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN;
 }
 
-/****************************************************************************
-********************************* Shared Memory *****************************
-**
-** The next subdivision of code manages the shared-memory primitives.
-*/
 #ifndef SQLITE_OMIT_WAL
 
+/* 
+** Windows will only let you create file view mappings
+** on allocation size granularity boundaries.
+** During sqlite3_os_init() we do a GetSystemInfo()
+** to get the granularity size.
+*/
+SYSTEM_INFO winSysInfo;
+
 /*
 ** Helper functions to obtain and relinquish the global mutex. The
 ** global mutex is used to protect the winLockInfo objects used by 
@@ -29962,7 +30657,7 @@
 **
 **   winShmEnterMutex()
 **     assert( winShmMutexHeld() );
-**   winEnterLeave()
+**   winShmLeaveMutex()
 */
 static void winShmEnterMutex(void){
   sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
@@ -29998,11 +30693,6 @@
 ** winShmMutexHeld() is true when reading or writing any other field
 ** in this structure.
 **
-** To avoid deadlocks, mutex and mutexBuf are always released in the
-** reverse order that they are acquired.  mutexBuf is always acquired
-** first and released last.  This invariant is check by asserting
-** sqlite3_mutex_notheld() on mutex whenever mutexBuf is acquired or
-** released.
 */
 struct winShmNode {
   sqlite3_mutex *mutex;      /* Mutex to access this object */
@@ -30036,17 +30726,21 @@
 ** Structure used internally by this VFS to record the state of an
 ** open shared memory connection.
 **
-** winShm.pFile->mutex must be held while reading or writing the
-** winShm.pNext and winShm.locks[] elements.
+** The following fields are initialized when this object is created and
+** are read-only thereafter:
 **
-** The winShm.pFile element is initialized when the object is created
-** and is read-only thereafter.
+**    winShm.pShmNode
+**    winShm.id
+**
+** All other fields are read/write.  The winShm.pShmNode->mutex must be held
+** while accessing any read/write fields.
 */
 struct winShm {
   winShmNode *pShmNode;      /* The underlying winShmNode object */
   winShm *pNext;             /* Next winShm with the same winShmNode */
   u8 hasMutex;               /* True if holding the winShmNode mutex */
-  u8 hasMutexBuf;            /* True if holding pFile->mutexBuf */
+  u16 sharedMask;            /* Mask of shared locks held */
+  u16 exclMask;              /* Mask of exclusive locks held */
 #ifdef SQLITE_DEBUG
   u8 id;                     /* Id of this connection with its winShmNode */
 #endif
@@ -30081,7 +30775,6 @@
   dwFlags = LOCKFILE_FAIL_IMMEDIATELY;
   if( lockType == _SHM_WRLCK ) dwFlags |= LOCKFILE_EXCLUSIVE_LOCK;
 
-  /* Find the first bit in lockMask that is set */
   memset(&ovlp, 0, sizeof(OVERLAPPED));
   ovlp.Offset = ofst;
 
@@ -30091,13 +30784,19 @@
   }else{
     rc = LockFileEx(pFile->hFile.h, dwFlags, 0, nByte, 0, &ovlp);
   }
-  if( !rc ){
-    OSTRACE(("SHM-LOCK %d %s ERROR 0x%08lx\n", 
-             pFile->hFile.h,
-             lockType==_SHM_UNLCK ? "UnlockFileEx" : "LockFileEx",
-             GetLastError()));
+  
+  if( rc!= 0 ){
+    rc = SQLITE_OK;
+  }else{
+    pFile->lastErrno =  GetLastError();
+    rc = SQLITE_BUSY;
   }
-  rc = (rc!=0) ? SQLITE_OK : SQLITE_BUSY;
+
+  OSTRACE(("SHM-LOCK %d %s %s 0x%08lx\n", 
+           pFile->hFile.h,
+           rc==SQLITE_OK ? "ok" : "failed",
+           lockType==_SHM_UNLCK ? "UnlockFileEx" : "LockFileEx",
+           pFile->lastErrno));
 
   return rc;
 }
@@ -30115,6 +30814,7 @@
 static void winShmPurge(sqlite3_vfs *pVfs, int deleteFlag){
   winShmNode **pp;
   winShmNode *p;
+  BOOL bRc;
   assert( winShmMutexHeld() );
   pp = &winShmNodeList;
   while( (p = *pp)!=0 ){
@@ -30122,13 +30822,25 @@
       int i;
       if( p->mutex ) sqlite3_mutex_free(p->mutex);
       for(i=0; i<p->nRegion; i++){
-        UnmapViewOfFile(p->aRegion[i].pMap);
-        CloseHandle(p->aRegion[i].hMap);
+        bRc = UnmapViewOfFile(p->aRegion[i].pMap);
+        OSTRACE(("SHM-PURGE pid-%d unmap region=%d %s\n",
+                 (int)GetCurrentProcessId(), i,
+                 bRc ? "ok" : "failed"));
+        bRc = CloseHandle(p->aRegion[i].hMap);
+        OSTRACE(("SHM-PURGE pid-%d close region=%d %s\n",
+                 (int)GetCurrentProcessId(), i,
+                 bRc ? "ok" : "failed"));
       }
-      if( p->hFile.h != INVALID_HANDLE_VALUE ) {
+      if( p->hFile.h != INVALID_HANDLE_VALUE ){
+        SimulateIOErrorBenign(1);
         winClose((sqlite3_file *)&p->hFile);
+        SimulateIOErrorBenign(0);
       }
-      if( deleteFlag ) winDelete(pVfs, p->zFilename, 0);
+      if( deleteFlag ){
+        SimulateIOErrorBenign(1);
+        winDelete(pVfs, p->zFilename, 0);
+        SimulateIOErrorBenign(0);
+      }
       *pp = p->pNext;
       sqlite3_free(p->aRegion);
       sqlite3_free(p);
@@ -30139,31 +30851,19 @@
 }
 
 /*
-** Open a shared-memory area.  This particular implementation uses
-** mmapped files.
-**
-** zName is a filename used to identify the shared-memory area.  The
-** implementation does not (and perhaps should not) use this name
-** directly, but rather use it as a template for finding an appropriate
-** name for the shared-memory storage.  In this implementation, the
-** string "-index" is appended to zName and used as the name of the
-** mmapped file.
+** Open the shared-memory area associated with database file pDbFd.
 **
 ** When opening a new shared-memory file, if no other instances of that
 ** file are currently open, in this process or in other processes, then
 ** the file must be truncated to zero length or have its header cleared.
 */
-static int winShmOpen(
-  sqlite3_file *fd      /* The file to which to attach shared memory */
-){
-  struct winFile *pDbFd;             /* Database to which to attach SHM */
+static int winOpenSharedMemory(winFile *pDbFd){
   struct winShm *p;                  /* The connection to be opened */
   struct winShmNode *pShmNode = 0;   /* The underlying mmapped file */
   int rc;                            /* Result code */
   struct winShmNode *pNew;           /* Newly allocated winShmNode */
   int nName;                         /* Size of zName in bytes */
 
-  pDbFd = (winFile*)fd;
   assert( pDbFd->pShm==0 );    /* Not previously opened */
 
   /* Allocate space for the new sqlite3_shm object.  Also speculatively
@@ -30206,10 +30906,11 @@
       rc = SQLITE_NOMEM;
       goto shm_open_err;
     }
+
     rc = winOpen(pDbFd->pVfs,
                  pShmNode->zFilename,             /* Name of the file (UTF-8) */
                  (sqlite3_file*)&pShmNode->hFile,  /* File handle here */
-                 SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE, /* Mode flags */
+                 SQLITE_OPEN_WAL | SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE, /* Mode flags */
                  0);
     if( SQLITE_OK!=rc ){
       rc = SQLITE_CANTOPEN_BKPT;
@@ -30234,14 +30935,24 @@
 
   /* Make the new connection a child of the winShmNode */
   p->pShmNode = pShmNode;
-  p->pNext = pShmNode->pFirst;
 #ifdef SQLITE_DEBUG
   p->id = pShmNode->nextShmId++;
 #endif
-  pShmNode->pFirst = p;
   pShmNode->nRef++;
   pDbFd->pShm = p;
   winShmLeaveMutex();
+
+  /* The reference count on pShmNode has already been incremented under
+  ** the cover of the winShmEnterMutex() mutex and the pointer from the
+  ** new (struct winShm) object to the pShmNode has been set. All that is
+  ** left to do is to link the new object into the linked list starting
+  ** at pShmNode->pFirst. This must be done while holding the pShmNode->mutex 
+  ** mutex.
+  */
+  sqlite3_mutex_enter(pShmNode->mutex);
+  p->pNext = pShmNode->pFirst;
+  pShmNode->pFirst = p;
+  sqlite3_mutex_leave(pShmNode->mutex);
   return SQLITE_OK;
 
   /* Jump here on any error */
@@ -30258,7 +30969,7 @@
 ** Close a connection to shared-memory.  Delete the underlying 
 ** storage if deleteFlag is true.
 */
-static int winShmClose(
+static int winShmUnmap(
   sqlite3_file *fd,          /* Database holding shared memory */
   int deleteFlag             /* Delete after closing if true */
 ){
@@ -30269,6 +30980,7 @@
 
   pDbFd = (winFile*)fd;
   p = pDbFd->pShm;
+  if( p==0 ) return SQLITE_OK;
   pShmNode = p->pShmNode;
 
   /* Remove connection p from the set of connections associated
@@ -30296,6 +31008,127 @@
 }
 
 /*
+** Change the lock state for a shared-memory segment.
+*/
+static int winShmLock(
+  sqlite3_file *fd,          /* Database file holding the shared memory */
+  int ofst,                  /* First lock to acquire or release */
+  int n,                     /* Number of locks to acquire or release */
+  int flags                  /* What to do with the lock */
+){
+  winFile *pDbFd = (winFile*)fd;        /* Connection holding shared memory */
+  winShm *p = pDbFd->pShm;              /* The shared memory being locked */
+  winShm *pX;                           /* For looping over all siblings */
+  winShmNode *pShmNode = p->pShmNode;
+  int rc = SQLITE_OK;                   /* Result code */
+  u16 mask;                             /* Mask of locks to take or release */
+
+  assert( ofst>=0 && ofst+n<=SQLITE_SHM_NLOCK );
+  assert( n>=1 );
+  assert( flags==(SQLITE_SHM_LOCK | SQLITE_SHM_SHARED)
+       || flags==(SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE)
+       || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED)
+       || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE) );
+  assert( n==1 || (flags & SQLITE_SHM_EXCLUSIVE)!=0 );
+
+  mask = (u16)((1U<<(ofst+n)) - (1U<<ofst));
+  assert( n>1 || mask==(1<<ofst) );
+  sqlite3_mutex_enter(pShmNode->mutex);
+  if( flags & SQLITE_SHM_UNLOCK ){
+    u16 allMask = 0; /* Mask of locks held by siblings */
+
+    /* See if any siblings hold this same lock */
+    for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
+      if( pX==p ) continue;
+      assert( (pX->exclMask & (p->exclMask|p->sharedMask))==0 );
+      allMask |= pX->sharedMask;
+    }
+
+    /* Unlock the system-level locks */
+    if( (mask & allMask)==0 ){
+      rc = winShmSystemLock(pShmNode, _SHM_UNLCK, ofst+WIN_SHM_BASE, n);
+    }else{
+      rc = SQLITE_OK;
+    }
+
+    /* Undo the local locks */
+    if( rc==SQLITE_OK ){
+      p->exclMask &= ~mask;
+      p->sharedMask &= ~mask;
+    } 
+  }else if( flags & SQLITE_SHM_SHARED ){
+    u16 allShared = 0;  /* Union of locks held by connections other than "p" */
+
+    /* Find out which shared locks are already held by sibling connections.
+    ** If any sibling already holds an exclusive lock, go ahead and return
+    ** SQLITE_BUSY.
+    */
+    for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
+      if( (pX->exclMask & mask)!=0 ){
+        rc = SQLITE_BUSY;
+        break;
+      }
+      allShared |= pX->sharedMask;
+    }
+
+    /* Get shared locks at the system level, if necessary */
+    if( rc==SQLITE_OK ){
+      if( (allShared & mask)==0 ){
+        rc = winShmSystemLock(pShmNode, _SHM_RDLCK, ofst+WIN_SHM_BASE, n);
+      }else{
+        rc = SQLITE_OK;
+      }
+    }
+
+    /* Get the local shared locks */
+    if( rc==SQLITE_OK ){
+      p->sharedMask |= mask;
+    }
+  }else{
+    /* Make sure no sibling connections hold locks that will block this
+    ** lock.  If any do, return SQLITE_BUSY right away.
+    */
+    for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
+      if( (pX->exclMask & mask)!=0 || (pX->sharedMask & mask)!=0 ){
+        rc = SQLITE_BUSY;
+        break;
+      }
+    }
+  
+    /* Get the exclusive locks at the system level.  Then if successful
+    ** also mark the local connection as being locked.
+    */
+    if( rc==SQLITE_OK ){
+      rc = winShmSystemLock(pShmNode, _SHM_WRLCK, ofst+WIN_SHM_BASE, n);
+      if( rc==SQLITE_OK ){
+        assert( (p->sharedMask & mask)==0 );
+        p->exclMask |= mask;
+      }
+    }
+  }
+  sqlite3_mutex_leave(pShmNode->mutex);
+  OSTRACE(("SHM-LOCK shmid-%d, pid-%d got %03x,%03x %s\n",
+           p->id, (int)GetCurrentProcessId(), p->sharedMask, p->exclMask,
+           rc ? "failed" : "ok"));
+  return rc;
+}
+
+/*
+** Implement a memory barrier or memory fence on shared memory.  
+**
+** All loads and stores begun before the barrier must complete before
+** any load or store begun after the barrier.
+*/
+static void winShmBarrier(
+  sqlite3_file *fd          /* Database holding the shared memory */
+){
+  UNUSED_PARAMETER(fd);
+  /* MemoryBarrier(); // does not work -- do not know why not */
+  winShmEnterMutex();
+  winShmLeaveMutex();
+}
+
+/*
 ** This function is called to obtain a pointer to region iRegion of the 
 ** shared-memory associated with the database file fd. Shared-memory regions 
 ** are numbered starting from zero. Each shared-memory region is szRegion 
@@ -30323,9 +31156,16 @@
 ){
   winFile *pDbFd = (winFile*)fd;
   winShm *p = pDbFd->pShm;
-  winShmNode *pShmNode = p->pShmNode;
+  winShmNode *pShmNode;
   int rc = SQLITE_OK;
 
+  if( !p ){
+    rc = winOpenSharedMemory(pDbFd);
+    if( rc!=SQLITE_OK ) return rc;
+    p = pDbFd->pShm;
+  }
+  pShmNode = p->pShmNode;
+
   sqlite3_mutex_enter(pShmNode->mutex);
   assert( szRegion==pShmNode->szRegion || pShmNode->nRegion==0 );
 
@@ -30342,6 +31182,7 @@
     */
     rc = winFileSize((sqlite3_file *)&pShmNode->hFile, &sz);
     if( rc!=SQLITE_OK ){
+      rc = SQLITE_IOERR_SHMSIZE;
       goto shmpage_out;
     }
 
@@ -30355,6 +31196,7 @@
       if( !isWrite ) goto shmpage_out;
       rc = winTruncate((sqlite3_file *)&pShmNode->hFile, nByte);
       if( rc!=SQLITE_OK ){
+        rc = SQLITE_IOERR_SHMSIZE;
         goto shmpage_out;
       }
     }
@@ -30376,10 +31218,18 @@
       hMap = CreateFileMapping(pShmNode->hFile.h, 
           NULL, PAGE_READWRITE, 0, nByte, NULL
       );
+      OSTRACE(("SHM-MAP pid-%d create region=%d nbyte=%d %s\n",
+               (int)GetCurrentProcessId(), pShmNode->nRegion, nByte,
+               hMap ? "ok" : "failed"));
       if( hMap ){
+        int iOffset = pShmNode->nRegion*szRegion;
+        int iOffsetShift = iOffset % winSysInfo.dwAllocationGranularity;
         pMap = MapViewOfFile(hMap, FILE_MAP_WRITE | FILE_MAP_READ,
-            0, 0, nByte
+            0, iOffset - iOffsetShift, szRegion + iOffsetShift
         );
+        OSTRACE(("SHM-MAP pid-%d map region=%d offset=%d size=%d %s\n",
+                 (int)GetCurrentProcessId(), pShmNode->nRegion, iOffset, szRegion,
+                 pMap ? "ok" : "failed"));
       }
       if( !pMap ){
         pShmNode->lastErrno = GetLastError();
@@ -30396,8 +31246,10 @@
 
 shmpage_out:
   if( pShmNode->nRegion>iRegion ){
+    int iOffset = iRegion*szRegion;
+    int iOffsetShift = iOffset % winSysInfo.dwAllocationGranularity;
     char *p = (char *)pShmNode->aRegion[iRegion].pMap;
-    *pp = (void *)&p[iRegion*szRegion];
+    *pp = (void *)&p[iOffsetShift];
   }else{
     *pp = 0;
   }
@@ -30405,98 +31257,49 @@
   return rc;
 }
 
-/*
-** Change the lock state for a shared-memory segment.
-*/
-static int winShmLock(
-  sqlite3_file *fd,          /* Database file holding the shared memory */
-  int ofst,                  /* First lock to acquire or release */
-  int n,                     /* Number of locks to acquire or release */
-  int flags                  /* What to do with the lock */
-){
-  winFile *pDbFd = (winFile*)fd;
-  winShm *p = pDbFd->pShm;
-  winShmNode *pShmNode = p->pShmNode;
-  int rc = SQLITE_PROTOCOL;
-
-  assert( ofst>=0 && ofst+n<=SQLITE_SHM_NLOCK );
-  assert( n>=1 );
-  assert( flags==(SQLITE_SHM_LOCK | SQLITE_SHM_SHARED)
-       || flags==(SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE)
-       || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED)
-       || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE) );
-  assert( n==1 || (flags & SQLITE_SHM_EXCLUSIVE)!=0 );
-
-  sqlite3_mutex_enter(pShmNode->mutex);
-  if( flags & SQLITE_SHM_UNLOCK ){
-    rc = winShmSystemLock(pShmNode, _SHM_UNLCK, ofst+WIN_SHM_BASE, n);
-  }else if( flags & SQLITE_SHM_SHARED ){
-    rc = winShmSystemLock(pShmNode, _SHM_RDLCK, ofst+WIN_SHM_BASE, n);
-  }else{
-    rc = winShmSystemLock(pShmNode, _SHM_WRLCK, ofst+WIN_SHM_BASE, n);
-  }
-  sqlite3_mutex_leave(pShmNode->mutex);
-  OSTRACE(("SHM-LOCK shmid-%d, pid-%d %s\n",
-           p->id, (int)GetCurrentProcessId(), rc ? "failed" : "ok"));
-  return rc;
-}
-
-/*
-** Implement a memory barrier or memory fence on shared memory.  
-**
-** All loads and stores begun before the barrier must complete before
-** any load or store begun after the barrier.
-*/
-static void winShmBarrier(
-  sqlite3_file *fd          /* Database holding the shared memory */
-){
-  UNUSED_PARAMETER(fd);
-  /* MemoryBarrier(); // does not work -- do not know why not */
-  winShmEnterMutex();
-  winShmLeaveMutex();
-}
-
 #else
-# define winShmOpen    0
 # define winShmMap     0
 # define winShmLock    0
 # define winShmBarrier 0
-# define winShmClose   0
+# define winShmUnmap   0
 #endif /* #ifndef SQLITE_OMIT_WAL */
+
 /*
-***************************** End Shared Memory *****************************
-****************************************************************************/
+** Here ends the implementation of all sqlite3_file methods.
+**
+********************** End sqlite3_file Methods *******************************
+******************************************************************************/
 
 /*
 ** This vector defines all the methods that can operate on an
 ** sqlite3_file for win32.
 */
 static const sqlite3_io_methods winIoMethod = {
-  2,                        /* iVersion */
-  winClose,
-  winRead,
-  winWrite,
-  winTruncate,
-  winSync,
-  winFileSize,
-  winLock,
-  winUnlock,
-  winCheckReservedLock,
-  winFileControl,
-  winSectorSize,
-  winDeviceCharacteristics,
-  winShmOpen,              /* xShmOpen */
-  winShmLock,              /* xShmLock */
-  winShmMap,               /* xShmMap */
-  winShmBarrier,           /* xShmBarrier */
-  winShmClose              /* xShmClose */
+  2,                              /* iVersion */
+  winClose,                       /* xClose */
+  winRead,                        /* xRead */
+  winWrite,                       /* xWrite */
+  winTruncate,                    /* xTruncate */
+  winSync,                        /* xSync */
+  winFileSize,                    /* xFileSize */
+  winLock,                        /* xLock */
+  winUnlock,                      /* xUnlock */
+  winCheckReservedLock,           /* xCheckReservedLock */
+  winFileControl,                 /* xFileControl */
+  winSectorSize,                  /* xSectorSize */
+  winDeviceCharacteristics,       /* xDeviceCharacteristics */
+  winShmMap,                      /* xShmMap */
+  winShmLock,                     /* xShmLock */
+  winShmBarrier,                  /* xShmBarrier */
+  winShmUnmap                     /* xShmUnmap */
 };
 
-/***************************************************************************
-** Here ends the I/O methods that form the sqlite3_io_methods object.
+/****************************************************************************
+**************************** sqlite3_vfs methods ****************************
 **
-** The next block of code implements the VFS methods.
-****************************************************************************/
+** This division contains the implementation of methods on the
+** sqlite3_vfs object.
+*/
 
 /*
 ** Convert a UTF-8 filename into whatever form the underlying
@@ -30530,6 +31333,13 @@
     "0123456789";
   size_t i, j;
   char zTempPath[MAX_PATH+1];
+
+  /* It's odd to simulate an io-error here, but really this is just
+  ** using the io-error infrastructure to test that SQLite handles this
+  ** function failing. 
+  */
+  SimulateIOError( return SQLITE_IOERR );
+
   if( sqlite3_temp_directory ){
     sqlite3_snprintf(MAX_PATH-30, zTempPath, "%s", sqlite3_temp_directory);
   }else if( isNT() ){
@@ -30561,16 +31371,26 @@
     }
 #endif
   }
+
+  /* Check that the output buffer is large enough for the temporary file 
+  ** name. If it is not, return SQLITE_ERROR.
+  */
+  if( (sqlite3Strlen30(zTempPath) + sqlite3Strlen30(SQLITE_TEMP_FILE_PREFIX) + 17) >= nBuf ){
+    return SQLITE_ERROR;
+  }
+
   for(i=sqlite3Strlen30(zTempPath); i>0 && zTempPath[i-1]=='\\'; i--){}
   zTempPath[i] = 0;
-  sqlite3_snprintf(nBuf-30, zBuf,
+
+  sqlite3_snprintf(nBuf-17, zBuf,
                    "%s\\"SQLITE_TEMP_FILE_PREFIX, zTempPath);
   j = sqlite3Strlen30(zBuf);
-  sqlite3_randomness(20, &zBuf[j]);
-  for(i=0; i<20; i++, j++){
+  sqlite3_randomness(15, &zBuf[j]);
+  for(i=0; i<15; i++, j++){
     zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
   }
   zBuf[j] = 0;
+
   OSTRACE(("TEMP FILENAME: %s\n", zBuf));
   return SQLITE_OK; 
 }
@@ -30656,9 +31476,60 @@
   int isTemp = 0;
 #endif
   winFile *pFile = (winFile*)id;
-  void *zConverted;                 /* Filename in OS encoding */
-  const char *zUtf8Name = zName;    /* Filename in UTF-8 encoding */
-  char zTmpname[MAX_PATH+1];        /* Buffer used to create temp filename */
+  void *zConverted;              /* Filename in OS encoding */
+  const char *zUtf8Name = zName; /* Filename in UTF-8 encoding */
+
+  /* If argument zPath is a NULL pointer, this function is required to open
+  ** a temporary file. Use this buffer to store the file name in.
+  */
+  char zTmpname[MAX_PATH+1];     /* Buffer used to create temp filename */
+
+  int rc = SQLITE_OK;            /* Function Return Code */
+#if !defined(NDEBUG) || SQLITE_OS_WINCE
+  int eType = flags&0xFFFFFF00;  /* Type of file to open */
+#endif
+
+  int isExclusive  = (flags & SQLITE_OPEN_EXCLUSIVE);
+  int isDelete     = (flags & SQLITE_OPEN_DELETEONCLOSE);
+  int isCreate     = (flags & SQLITE_OPEN_CREATE);
+#ifndef NDEBUG
+  int isReadonly   = (flags & SQLITE_OPEN_READONLY);
+#endif
+  int isReadWrite  = (flags & SQLITE_OPEN_READWRITE);
+
+#ifndef NDEBUG
+  int isOpenJournal = (isCreate && (
+        eType==SQLITE_OPEN_MASTER_JOURNAL 
+     || eType==SQLITE_OPEN_MAIN_JOURNAL 
+     || eType==SQLITE_OPEN_WAL
+  ));
+#endif
+
+  /* Check the following statements are true: 
+  **
+  **   (a) Exactly one of the READWRITE and READONLY flags must be set, and 
+  **   (b) if CREATE is set, then READWRITE must also be set, and
+  **   (c) if EXCLUSIVE is set, then CREATE must also be set.
+  **   (d) if DELETEONCLOSE is set, then CREATE must also be set.
+  */
+  assert((isReadonly==0 || isReadWrite==0) && (isReadWrite || isReadonly));
+  assert(isCreate==0 || isReadWrite);
+  assert(isExclusive==0 || isCreate);
+  assert(isDelete==0 || isCreate);
+
+  /* The main DB, main journal, WAL file and master journal are never 
+  ** automatically deleted. Nor are they ever temporary files.  */
+  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_DB );
+  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_JOURNAL );
+  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MASTER_JOURNAL );
+  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_WAL );
+
+  /* Assert that the upper layer has set one of the "file-type" flags. */
+  assert( eType==SQLITE_OPEN_MAIN_DB      || eType==SQLITE_OPEN_TEMP_DB 
+       || eType==SQLITE_OPEN_MAIN_JOURNAL || eType==SQLITE_OPEN_TEMP_JOURNAL 
+       || eType==SQLITE_OPEN_SUBJOURNAL   || eType==SQLITE_OPEN_MASTER_JOURNAL 
+       || eType==SQLITE_OPEN_TRANSIENT_DB || eType==SQLITE_OPEN_WAL
+  );
 
   assert( id!=0 );
   UNUSED_PARAMETER(pVfs);
@@ -30669,7 +31540,8 @@
   ** temporary file name to use 
   */
   if( !zUtf8Name ){
-    int rc = getTempname(MAX_PATH+1, zTmpname);
+    assert(isDelete && !isOpenJournal);
+    rc = getTempname(MAX_PATH+1, zTmpname);
     if( rc!=SQLITE_OK ){
       return rc;
     }
@@ -30682,29 +31554,31 @@
     return SQLITE_NOMEM;
   }
 
-  if( flags & SQLITE_OPEN_READWRITE ){
+  if( isReadWrite ){
     dwDesiredAccess = GENERIC_READ | GENERIC_WRITE;
   }else{
     dwDesiredAccess = GENERIC_READ;
   }
+
   /* SQLITE_OPEN_EXCLUSIVE is used to make sure that a new file is 
   ** created. SQLite doesn't use it to indicate "exclusive access" 
   ** as it is usually understood.
   */
-  assert(!(flags & SQLITE_OPEN_EXCLUSIVE) || (flags & SQLITE_OPEN_CREATE));
-  if( flags & SQLITE_OPEN_EXCLUSIVE ){
+  if( isExclusive ){
     /* Creates a new file, only if it does not already exist. */
     /* If the file exists, it fails. */
     dwCreationDisposition = CREATE_NEW;
-  }else if( flags & SQLITE_OPEN_CREATE ){
+  }else if( isCreate ){
     /* Open existing file, or create if it doesn't exist */
     dwCreationDisposition = OPEN_ALWAYS;
   }else{
     /* Opens a file, only if it exists. */
     dwCreationDisposition = OPEN_EXISTING;
   }
+
   dwShareMode = FILE_SHARE_READ | FILE_SHARE_WRITE;
-  if( flags & SQLITE_OPEN_DELETEONCLOSE ){
+
+  if( isDelete ){
 #if SQLITE_OS_WINCE
     dwFlagsAndAttributes = FILE_ATTRIBUTE_HIDDEN;
     isTemp = 1;
@@ -30721,6 +31595,7 @@
 #if SQLITE_OS_WINCE
   dwFlagsAndAttributes |= FILE_FLAG_RANDOM_ACCESS;
 #endif
+
   if( isNT() ){
     h = CreateFileW((WCHAR*)zConverted,
        dwDesiredAccess,
@@ -30746,25 +31621,30 @@
     );
 #endif
   }
+
   OSTRACE(("OPEN %d %s 0x%lx %s\n", 
            h, zName, dwDesiredAccess, 
            h==INVALID_HANDLE_VALUE ? "failed" : "ok"));
+
   if( h==INVALID_HANDLE_VALUE ){
+    pFile->lastErrno = GetLastError();
     free(zConverted);
-    if( flags & SQLITE_OPEN_READWRITE ){
+    if( isReadWrite ){
       return winOpen(pVfs, zName, id, 
-             ((flags|SQLITE_OPEN_READONLY)&~SQLITE_OPEN_READWRITE), pOutFlags);
+             ((flags|SQLITE_OPEN_READONLY)&~(SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE)), pOutFlags);
     }else{
       return SQLITE_CANTOPEN_BKPT;
     }
   }
+
   if( pOutFlags ){
-    if( flags & SQLITE_OPEN_READWRITE ){
+    if( isReadWrite ){
       *pOutFlags = SQLITE_OPEN_READWRITE;
     }else{
       *pOutFlags = SQLITE_OPEN_READONLY;
     }
   }
+
   memset(pFile, 0, sizeof(*pFile));
   pFile->pMethod = &winIoMethod;
   pFile->h = h;
@@ -30773,9 +31653,9 @@
   pFile->pShm = 0;
   pFile->zPath = zName;
   pFile->sectorSize = getSectorSize(pVfs, zUtf8Name);
+
 #if SQLITE_OS_WINCE
-  if( (flags & (SQLITE_OPEN_READWRITE|SQLITE_OPEN_MAIN_DB)) ==
-               (SQLITE_OPEN_READWRITE|SQLITE_OPEN_MAIN_DB)
+  if( isReadWrite && eType==SQLITE_OPEN_MAIN_DB
        && !winceCreateLock(zName, pFile)
   ){
     CloseHandle(h);
@@ -30789,8 +31669,9 @@
   {
     free(zConverted);
   }
+
   OpenCounter(+1);
-  return SQLITE_OK;
+  return rc;
 }
 
 /*
@@ -30814,13 +31695,15 @@
   int cnt = 0;
   DWORD rc;
   DWORD error = 0;
-  void *zConverted = convertUtf8Filename(zFilename);
+  void *zConverted;
   UNUSED_PARAMETER(pVfs);
   UNUSED_PARAMETER(syncDir);
+
+  SimulateIOError(return SQLITE_IOERR_DELETE);
+  zConverted = convertUtf8Filename(zFilename);
   if( zConverted==0 ){
     return SQLITE_NOMEM;
   }
-  SimulateIOError(return SQLITE_IOERR_DELETE);
   if( isNT() ){
     do{
       DeleteFileW(zConverted);
@@ -30933,12 +31816,14 @@
 ){
   
 #if defined(__CYGWIN__)
+  SimulateIOError( return SQLITE_ERROR );
   UNUSED_PARAMETER(nFull);
   cygwin_conv_to_full_win32_path(zRelative, zFull);
   return SQLITE_OK;
 #endif
 
 #if SQLITE_OS_WINCE
+  SimulateIOError( return SQLITE_ERROR );
   UNUSED_PARAMETER(nFull);
   /* WinCE has no concept of a relative pathname, or so I am told. */
   sqlite3_snprintf(pVfs->mxPathname, zFull, "%s", zRelative);
@@ -30949,6 +31834,13 @@
   int nByte;
   void *zConverted;
   char *zOut;
+
+  /* It's odd to simulate an io-error here, but really this is just
+  ** using the io-error infrastructure to test that SQLite handles this
+  ** function failing. This function could fail if, for example, the
+  ** current working directory has been unlinked.
+  */
+  SimulateIOError( return SQLITE_ERROR );
   UNUSED_PARAMETER(nFull);
   zConverted = convertUtf8Filename(zRelative);
   if( isNT() ){
@@ -31016,7 +31908,9 @@
   ** to get the drive letter to look up the sector
   ** size.
   */
+  SimulateIOErrorBenign(1);
   rc = winFullPathname(pVfs, zRelative, MAX_PATH, zFullpath);
+  SimulateIOErrorBenign(0);
   if( rc == SQLITE_OK )
   {
     void *zConverted = convertUtf8Filename(zFullpath);
@@ -31296,6 +32190,13 @@
     winCurrentTimeInt64, /* xCurrentTimeInt64 */
   };
 
+#ifndef SQLITE_OMIT_WAL
+  /* get memory map allocation granularity */
+  memset(&winSysInfo, 0, sizeof(SYSTEM_INFO));
+  GetSystemInfo(&winSysInfo);
+  assert(winSysInfo.dwAllocationGranularity > 0);
+#endif
+
   sqlite3_vfs_register(&winVfs, 1);
   return SQLITE_OK; 
 }
@@ -31345,7 +32246,7 @@
 */
 
 /* Size of the Bitvec structure in bytes. */
-#define BITVEC_SZ        (sizeof(void*)*128)  /* 512 on 32bit.  1024 on 64bit */
+#define BITVEC_SZ        512
 
 /* Round the union size down to the nearest pointer boundary, since that's how 
 ** it will be aligned within the Bitvec struct. */
@@ -31860,12 +32761,16 @@
 */
 SQLITE_PRIVATE int sqlite3PcacheInitialize(void){
   if( sqlite3GlobalConfig.pcache.xInit==0 ){
+    /* IMPLEMENTATION-OF: R-26801-64137 If the xInit() method is NULL, then the
+    ** built-in default page cache is used instead of the application defined
+    ** page cache. */
     sqlite3PCacheSetDefault();
   }
   return sqlite3GlobalConfig.pcache.xInit(sqlite3GlobalConfig.pcache.pArg);
 }
 SQLITE_PRIVATE void sqlite3PcacheShutdown(void){
   if( sqlite3GlobalConfig.pcache.xShutdown ){
+    /* IMPLEMENTATION-OF: R-26000-56589 The xShutdown() method may be NULL. */
     sqlite3GlobalConfig.pcache.xShutdown(sqlite3GlobalConfig.pcache.pArg);
   }
 }
@@ -32326,8 +33231,13 @@
 typedef struct PgHdr1 PgHdr1;
 typedef struct PgFreeslot PgFreeslot;
 
-/* Pointers to structures of this type are cast and returned as 
-** opaque sqlite3_pcache* handles
+/* Each page cache is an instance of the following object.  Every
+** open database file (including each in-memory database and each
+** temporary or transient database) has a single page cache which
+** is an instance of this object.
+**
+** Pointers to structures of this type are cast and returned as 
+** opaque sqlite3_pcache* handles.
 */
 struct PCache1 {
   /* Cache configuration parameters. Page size (szPage) and the purgeable
@@ -32387,6 +33297,9 @@
 
   /* Variables related to SQLITE_CONFIG_PAGECACHE settings. */
   int szSlot;                         /* Size of each free slot */
+  int nSlot;                          /* The number of pcache slots */
+  int nFreeSlot;                      /* Number of unused pcache slots */
+  int nReserve;                       /* Try to keep nFreeSlot above this */
   void *pStart, *pEnd;                /* Bounds of pagecache malloc range */
   PgFreeslot *pFree;                  /* Free page blocks */
   int isInit;                         /* True if initialized */
@@ -32434,6 +33347,8 @@
     PgFreeslot *p;
     sz = ROUNDDOWN8(sz);
     pcache1.szSlot = sz;
+    pcache1.nSlot = pcache1.nFreeSlot = n;
+    pcache1.nReserve = n>90 ? 10 : (n/10 + 1);
     pcache1.pStart = pBuf;
     pcache1.pFree = 0;
     while( n-- ){
@@ -32455,11 +33370,13 @@
 static void *pcache1Alloc(int nByte){
   void *p;
   assert( sqlite3_mutex_held(pcache1.mutex) );
+  sqlite3StatusSet(SQLITE_STATUS_PAGECACHE_SIZE, nByte);
   if( nByte<=pcache1.szSlot && pcache1.pFree ){
     assert( pcache1.isInit );
     p = (PgHdr1 *)pcache1.pFree;
     pcache1.pFree = pcache1.pFree->pNext;
-    sqlite3StatusSet(SQLITE_STATUS_PAGECACHE_SIZE, nByte);
+    pcache1.nFreeSlot--;
+    assert( pcache1.nFreeSlot>=0 );
     sqlite3StatusAdd(SQLITE_STATUS_PAGECACHE_USED, 1);
   }else{
 
@@ -32493,6 +33410,8 @@
     pSlot = (PgFreeslot*)p;
     pSlot->pNext = pcache1.pFree;
     pcache1.pFree = pSlot;
+    pcache1.nFreeSlot++;
+    assert( pcache1.nFreeSlot<=pcache1.nSlot );
   }else{
     int iSize;
     assert( sqlite3MemdebugHasType(p, MEMTYPE_PCACHE) );
@@ -32503,6 +33422,25 @@
   }
 }
 
+#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
+/*
+** Return the size of a pcache allocation
+*/
+static int pcache1MemSize(void *p){
+  assert( sqlite3_mutex_held(pcache1.mutex) );
+  if( p>=pcache1.pStart && p<pcache1.pEnd ){
+    return pcache1.szSlot;
+  }else{
+    int iSize;
+    assert( sqlite3MemdebugHasType(p, MEMTYPE_PCACHE) );
+    sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
+    iSize = sqlite3MallocSize(p);
+    sqlite3MemdebugSetType(p, MEMTYPE_PCACHE);
+    return iSize;
+  }
+}
+#endif /* SQLITE_ENABLE_MEMORY_MANAGEMENT */
+
 /*
 ** Allocate a new page object initially associated with cache pCache.
 */
@@ -32559,6 +33497,32 @@
   pcache1LeaveMutex();
 }
 
+
+/*
+** Return true if it desirable to avoid allocating a new page cache
+** entry.
+**
+** If memory was allocated specifically to the page cache using
+** SQLITE_CONFIG_PAGECACHE but that memory has all been used, then
+** it is desirable to avoid allocating a new page cache entry because
+** presumably SQLITE_CONFIG_PAGECACHE was suppose to be sufficient
+** for all page cache needs and we should not need to spill the
+** allocation onto the heap.
+**
+** Or, the heap is used for all page cache memory put the heap is
+** under memory pressure, then again it is desirable to avoid
+** allocating a new page cache entry in order to avoid stressing
+** the heap even further.
+*/
+static int pcache1UnderMemoryPressure(PCache1 *pCache){
+  assert( sqlite3_mutex_held(pcache1.mutex) );
+  if( pcache1.nSlot && pCache->szPage<=pcache1.szSlot ){
+    return pcache1.nFreeSlot<pcache1.nReserve;
+  }else{
+    return sqlite3HeapNearlyFull();
+  }
+}
+
 /******************************************************************************/
 /******** General Implementation Functions ************************************/
 
@@ -32800,14 +33764,16 @@
 **   2. If createFlag==0 and the page is not already in the cache, NULL is
 **      returned.
 **
-**   3. If createFlag is 1, and the page is not already in the cache,
-**      and if either of the following are true, return NULL:
+**   3. If createFlag is 1, and the page is not already in the cache, then
+**      return NULL (do not allocate a new page) if any of the following
+**      conditions are true:
 **
 **       (a) the number of pages pinned by the cache is greater than
 **           PCache1.nMax, or
+**
 **       (b) the number of pages pinned by the cache is greater than
 **           the sum of nMax for all purgeable caches, less the sum of 
-**           nMin for all other purgeable caches. 
+**           nMin for all other purgeable caches, or
 **
 **   4. If none of the first three conditions apply and the cache is marked
 **      as purgeable, and if one of the following is true:
@@ -32819,6 +33785,9 @@
 **           already equal to or greater than the sum of nMax for all
 **           purgeable caches,
 **
+**       (c) The system is under memory pressure and wants to avoid
+**           unnecessary pages cache entry allocations
+**
 **      then attempt to recycle a page from the LRU list. If it is the right
 **      size, return the recycled buffer. Otherwise, free the buffer and
 **      proceed to step 5. 
@@ -32850,6 +33819,7 @@
   if( createFlag==1 && (
         nPinned>=(pcache1.nMaxPage+pCache->nMin-pcache1.nMinPage)
      || nPinned>=(pCache->nMax * 9 / 10)
+     || pcache1UnderMemoryPressure(pCache)
   )){
     goto fetch_out;
   }
@@ -32860,7 +33830,9 @@
 
   /* Step 4. Try to recycle a page buffer if appropriate. */
   if( pCache->bPurgeable && pcache1.pLruTail && (
-     (pCache->nPage+1>=pCache->nMax) || pcache1.nCurrentPage>=pcache1.nMaxPage
+         (pCache->nPage+1>=pCache->nMax)
+      || pcache1.nCurrentPage>=pcache1.nMaxPage
+      || pcache1UnderMemoryPressure(pCache)
   )){
     pPage = pcache1.pLruTail;
     pcache1RemoveFromHash(pPage);
@@ -33003,6 +33975,7 @@
 */
 static void pcache1Destroy(sqlite3_pcache *p){
   PCache1 *pCache = (PCache1 *)p;
+  assert( pCache->bPurgeable || (pCache->nMax==0 && pCache->nMin==0) );
   pcache1EnterMutex();
   pcache1TruncateUnsafe(pCache, 0);
   pcache1.nMaxPage -= pCache->nMax;
@@ -33050,8 +34023,8 @@
   if( pcache1.pStart==0 ){
     PgHdr1 *p;
     pcache1EnterMutex();
-    while( (nReq<0 || nFree<nReq) && (p=pcache1.pLruTail) ){
-      nFree += sqlite3MallocSize(PGHDR1_TO_PAGE(p));
+    while( (nReq<0 || nFree<nReq) && ((p=pcache1.pLruTail)!=0) ){
+      nFree += pcache1MemSize(PGHDR1_TO_PAGE(p));
       pcache1PinPage(p);
       pcache1RemoveFromHash(p);
       pcache1FreePage(p);
@@ -33560,7 +34533,7 @@
 # define sqlite3WalBeginReadTransaction(y,z)   0
 # define sqlite3WalEndReadTransaction(z)
 # define sqlite3WalRead(v,w,x,y,z)             0
-# define sqlite3WalDbsize(y,z)
+# define sqlite3WalDbsize(y)                   0
 # define sqlite3WalBeginWriteTransaction(y)    0
 # define sqlite3WalEndWriteTransaction(x)      0
 # define sqlite3WalUndo(x,y,z)                 0
@@ -33596,9 +34569,8 @@
 /* Read a page from the write-ahead log, if it is present. */
 SQLITE_PRIVATE int sqlite3WalRead(Wal *pWal, Pgno pgno, int *pInWal, int nOut, u8 *pOut);
 
-/* Return the size of the database as it existed at the beginning
-** of the snapshot */
-SQLITE_PRIVATE void sqlite3WalDbsize(Wal *pWal, Pgno *pPgno);
+/* If the WAL is not empty, return the size of the database. */
+SQLITE_PRIVATE Pgno sqlite3WalDbsize(Wal *pWal);
 
 /* Obtain or release the WRITER lock. */
 SQLITE_PRIVATE int sqlite3WalBeginWriteTransaction(Wal *pWal);
@@ -33644,8 +34616,12 @@
 /************** End of wal.h *************************************************/
 /************** Continuing where we left off in pager.c **********************/
 
-/*
-******************** NOTES ON THE DESIGN OF THE PAGER ************************
+
+/******************* NOTES ON THE DESIGN OF THE PAGER ************************
+**
+** This comment block describes invariants that hold when using a rollback
+** journal.  These invariants do not apply for journal_mode=WAL,
+** journal_mode=MEMORY, or journal_mode=OFF.
 **
 ** Within this comment block, a page is deemed to have been synced
 ** automatically as soon as it is written when PRAGMA synchronous=OFF.
@@ -33679,7 +34655,7 @@
 **     transaction.
 ** 
 ** (3) Writes to the database file are an integer multiple of the page size
-**     in length and are aligned to a page boundary.
+**     in length and are aligned on a page boundary.
 ** 
 ** (4) Reads from the database file are either aligned on a page boundary and
 **     an integer multiple of the page size in length or are taken from the
@@ -33710,7 +34686,8 @@
 ** 
 ** (9) Whenever the database file is modified, at least one bit in the range
 **     of bytes from 24 through 39 inclusive will be changed prior to releasing
-**     the EXCLUSIVE lock.
+**     the EXCLUSIVE lock, thus signaling other connections on the same
+**     database to flush their caches.
 **
 ** (10) The pattern of bits in bytes 24 through 39 shall not repeat in less
 **      than one billion transactions.
@@ -33723,7 +34700,8 @@
 **
 ** (13) A SHARED lock is held on the database file while reading any
 **      content out of the database file.
-*/
+**
+******************************************************************************/
 
 /*
 ** Macros for troubleshooting.  Normally turned off
@@ -33748,58 +34726,279 @@
 #define FILEHANDLEID(fd) ((int)fd)
 
 /*
-** The page cache as a whole is always in one of the following
-** states:
+** The Pager.eState variable stores the current 'state' of a pager. A
+** pager may be in any one of the seven states shown in the following
+** state diagram.
 **
-**   PAGER_UNLOCK        The page cache is not currently reading or 
-**                       writing the database file.  There is no
-**                       data held in memory.  This is the initial
-**                       state.
+**                            OPEN <------+------+
+**                              |         |      |
+**                              V         |      |
+**               +---------> READER-------+      |
+**               |              |                |
+**               |              V                |
+**               |<-------WRITER_LOCKED------> ERROR
+**               |              |                ^  
+**               |              V                |
+**               |<------WRITER_CACHEMOD-------->|
+**               |              |                |
+**               |              V                |
+**               |<-------WRITER_DBMOD---------->|
+**               |              |                |
+**               |              V                |
+**               +<------WRITER_FINISHED-------->+
 **
-**   PAGER_SHARED        The page cache is reading the database.
-**                       Writing is not permitted.  There can be
-**                       multiple readers accessing the same database
-**                       file at the same time.
 **
-**   PAGER_RESERVED      This process has reserved the database for writing
-**                       but has not yet made any changes.  Only one process
-**                       at a time can reserve the database.  The original
-**                       database file has not been modified so other
-**                       processes may still be reading the on-disk
-**                       database file.
+** List of state transitions and the C [function] that performs each:
+** 
+**   OPEN              -> READER              [sqlite3PagerSharedLock]
+**   READER            -> OPEN                [pager_unlock]
 **
-**   PAGER_EXCLUSIVE     The page cache is writing the database.
-**                       Access is exclusive.  No other processes or
-**                       threads can be reading or writing while one
-**                       process is writing.
+**   READER            -> WRITER_LOCKED       [sqlite3PagerBegin]
+**   WRITER_LOCKED     -> WRITER_CACHEMOD     [pager_open_journal]
+**   WRITER_CACHEMOD   -> WRITER_DBMOD        [syncJournal]
+**   WRITER_DBMOD      -> WRITER_FINISHED     [sqlite3PagerCommitPhaseOne]
+**   WRITER_***        -> READER              [pager_end_transaction]
 **
-**   PAGER_SYNCED        The pager moves to this state from PAGER_EXCLUSIVE
-**                       after all dirty pages have been written to the
-**                       database file and the file has been synced to
-**                       disk. All that remains to do is to remove or
-**                       truncate the journal file and the transaction 
-**                       will be committed.
+**   WRITER_***        -> ERROR               [pager_error]
+**   ERROR             -> OPEN                [pager_unlock]
+** 
 **
-** The page cache comes up in PAGER_UNLOCK.  The first time a
-** sqlite3PagerGet() occurs, the state transitions to PAGER_SHARED.
-** After all pages have been released using sqlite_page_unref(),
-** the state transitions back to PAGER_UNLOCK.  The first time
-** that sqlite3PagerWrite() is called, the state transitions to
-** PAGER_RESERVED.  (Note that sqlite3PagerWrite() can only be
-** called on an outstanding page which means that the pager must
-** be in PAGER_SHARED before it transitions to PAGER_RESERVED.)
-** PAGER_RESERVED means that there is an open rollback journal.
-** The transition to PAGER_EXCLUSIVE occurs before any changes
-** are made to the database file, though writes to the rollback
-** journal occurs with just PAGER_RESERVED.  After an sqlite3PagerRollback()
-** or sqlite3PagerCommitPhaseTwo(), the state can go back to PAGER_SHARED,
-** or it can stay at PAGER_EXCLUSIVE if we are in exclusive access mode.
+**  OPEN:
+**
+**    The pager starts up in this state. Nothing is guaranteed in this
+**    state - the file may or may not be locked and the database size is
+**    unknown. The database may not be read or written.
+**
+**    * No read or write transaction is active.
+**    * Any lock, or no lock at all, may be held on the database file.
+**    * The dbSize, dbOrigSize and dbFileSize variables may not be trusted.
+**
+**  READER:
+**
+**    In this state all the requirements for reading the database in 
+**    rollback (non-WAL) mode are met. Unless the pager is (or recently
+**    was) in exclusive-locking mode, a user-level read transaction is 
+**    open. The database size is known in this state.
+**
+**    A connection running with locking_mode=normal enters this state when
+**    it opens a read-transaction on the database and returns to state
+**    OPEN after the read-transaction is completed. However a connection
+**    running in locking_mode=exclusive (including temp databases) remains in
+**    this state even after the read-transaction is closed. The only way
+**    a locking_mode=exclusive connection can transition from READER to OPEN
+**    is via the ERROR state (see below).
+** 
+**    * A read transaction may be active (but a write-transaction cannot).
+**    * A SHARED or greater lock is held on the database file.
+**    * The dbSize variable may be trusted (even if a user-level read 
+**      transaction is not active). The dbOrigSize and dbFileSize variables
+**      may not be trusted at this point.
+**    * If the database is a WAL database, then the WAL connection is open.
+**    * Even if a read-transaction is not open, it is guaranteed that 
+**      there is no hot-journal in the file-system.
+**
+**  WRITER_LOCKED:
+**
+**    The pager moves to this state from READER when a write-transaction
+**    is first opened on the database. In WRITER_LOCKED state, all locks 
+**    required to start a write-transaction are held, but no actual 
+**    modifications to the cache or database have taken place.
+**
+**    In rollback mode, a RESERVED or (if the transaction was opened with 
+**    BEGIN EXCLUSIVE) EXCLUSIVE lock is obtained on the database file when
+**    moving to this state, but the journal file is not written to or opened 
+**    to in this state. If the transaction is committed or rolled back while 
+**    in WRITER_LOCKED state, all that is required is to unlock the database 
+**    file.
+**
+**    IN WAL mode, WalBeginWriteTransaction() is called to lock the log file.
+**    If the connection is running with locking_mode=exclusive, an attempt
+**    is made to obtain an EXCLUSIVE lock on the database file.
+**
+**    * A write transaction is active.
+**    * If the connection is open in rollback-mode, a RESERVED or greater 
+**      lock is held on the database file.
+**    * If the connection is open in WAL-mode, a WAL write transaction
+**      is open (i.e. sqlite3WalBeginWriteTransaction() has been successfully
+**      called).
+**    * The dbSize, dbOrigSize and dbFileSize variables are all valid.
+**    * The contents of the pager cache have not been modified.
+**    * The journal file may or may not be open.
+**    * Nothing (not even the first header) has been written to the journal.
+**
+**  WRITER_CACHEMOD:
+**
+**    A pager moves from WRITER_LOCKED state to this state when a page is
+**    first modified by the upper layer. In rollback mode the journal file
+**    is opened (if it is not already open) and a header written to the
+**    start of it. The database file on disk has not been modified.
+**
+**    * A write transaction is active.
+**    * A RESERVED or greater lock is held on the database file.
+**    * The journal file is open and the first header has been written 
+**      to it, but the header has not been synced to disk.
+**    * The contents of the page cache have been modified.
+**
+**  WRITER_DBMOD:
+**
+**    The pager transitions from WRITER_CACHEMOD into WRITER_DBMOD state
+**    when it modifies the contents of the database file. WAL connections
+**    never enter this state (since they do not modify the database file,
+**    just the log file).
+**
+**    * A write transaction is active.
+**    * An EXCLUSIVE or greater lock is held on the database file.
+**    * The journal file is open and the first header has been written 
+**      and synced to disk.
+**    * The contents of the page cache have been modified (and possibly
+**      written to disk).
+**
+**  WRITER_FINISHED:
+**
+**    It is not possible for a WAL connection to enter this state.
+**
+**    A rollback-mode pager changes to WRITER_FINISHED state from WRITER_DBMOD
+**    state after the entire transaction has been successfully written into the
+**    database file. In this state the transaction may be committed simply
+**    by finalizing the journal file. Once in WRITER_FINISHED state, it is 
+**    not possible to modify the database further. At this point, the upper 
+**    layer must either commit or rollback the transaction.
+**
+**    * A write transaction is active.
+**    * An EXCLUSIVE or greater lock is held on the database file.
+**    * All writing and syncing of journal and database data has finished.
+**      If no error occured, all that remains is to finalize the journal to
+**      commit the transaction. If an error did occur, the caller will need
+**      to rollback the transaction. 
+**
+**  ERROR:
+**
+**    The ERROR state is entered when an IO or disk-full error (including
+**    SQLITE_IOERR_NOMEM) occurs at a point in the code that makes it 
+**    difficult to be sure that the in-memory pager state (cache contents, 
+**    db size etc.) are consistent with the contents of the file-system.
+**
+**    Temporary pager files may enter the ERROR state, but in-memory pagers
+**    cannot.
+**
+**    For example, if an IO error occurs while performing a rollback, 
+**    the contents of the page-cache may be left in an inconsistent state.
+**    At this point it would be dangerous to change back to READER state
+**    (as usually happens after a rollback). Any subsequent readers might
+**    report database corruption (due to the inconsistent cache), and if
+**    they upgrade to writers, they may inadvertently corrupt the database
+**    file. To avoid this hazard, the pager switches into the ERROR state
+**    instead of READER following such an error.
+**
+**    Once it has entered the ERROR state, any attempt to use the pager
+**    to read or write data returns an error. Eventually, once all 
+**    outstanding transactions have been abandoned, the pager is able to
+**    transition back to OPEN state, discarding the contents of the 
+**    page-cache and any other in-memory state at the same time. Everything
+**    is reloaded from disk (and, if necessary, hot-journal rollback peformed)
+**    when a read-transaction is next opened on the pager (transitioning
+**    the pager into READER state). At that point the system has recovered 
+**    from the error.
+**
+**    Specifically, the pager jumps into the ERROR state if:
+**
+**      1. An error occurs while attempting a rollback. This happens in
+**         function sqlite3PagerRollback().
+**
+**      2. An error occurs while attempting to finalize a journal file
+**         following a commit in function sqlite3PagerCommitPhaseTwo().
+**
+**      3. An error occurs while attempting to write to the journal or
+**         database file in function pagerStress() in order to free up
+**         memory.
+**
+**    In other cases, the error is returned to the b-tree layer. The b-tree
+**    layer then attempts a rollback operation. If the error condition 
+**    persists, the pager enters the ERROR state via condition (1) above.
+**
+**    Condition (3) is necessary because it can be triggered by a read-only
+**    statement executed within a transaction. In this case, if the error
+**    code were simply returned to the user, the b-tree layer would not
+**    automatically attempt a rollback, as it assumes that an error in a
+**    read-only statement cannot leave the pager in an internally inconsistent 
+**    state.
+**
+**    * The Pager.errCode variable is set to something other than SQLITE_OK.
+**    * There are one or more outstanding references to pages (after the
+**      last reference is dropped the pager should move back to OPEN state).
+**    * The pager is not an in-memory pager.
+**    
+**
+** Notes:
+**
+**   * A pager is never in WRITER_DBMOD or WRITER_FINISHED state if the
+**     connection is open in WAL mode. A WAL connection is always in one
+**     of the first four states.
+**
+**   * Normally, a connection open in exclusive mode is never in PAGER_OPEN
+**     state. There are two exceptions: immediately after exclusive-mode has
+**     been turned on (and before any read or write transactions are 
+**     executed), and when the pager is leaving the "error state".
+**
+**   * See also: assert_pager_state().
 */
-#define PAGER_UNLOCK      0
-#define PAGER_SHARED      1   /* same as SHARED_LOCK */
-#define PAGER_RESERVED    2   /* same as RESERVED_LOCK */
-#define PAGER_EXCLUSIVE   4   /* same as EXCLUSIVE_LOCK */
-#define PAGER_SYNCED      5
+#define PAGER_OPEN                  0
+#define PAGER_READER                1
+#define PAGER_WRITER_LOCKED         2
+#define PAGER_WRITER_CACHEMOD       3
+#define PAGER_WRITER_DBMOD          4
+#define PAGER_WRITER_FINISHED       5
+#define PAGER_ERROR                 6
+
+/*
+** The Pager.eLock variable is almost always set to one of the 
+** following locking-states, according to the lock currently held on
+** the database file: NO_LOCK, SHARED_LOCK, RESERVED_LOCK or EXCLUSIVE_LOCK.
+** This variable is kept up to date as locks are taken and released by
+** the pagerLockDb() and pagerUnlockDb() wrappers.
+**
+** If the VFS xLock() or xUnlock() returns an error other than SQLITE_BUSY
+** (i.e. one of the SQLITE_IOERR subtypes), it is not clear whether or not
+** the operation was successful. In these circumstances pagerLockDb() and
+** pagerUnlockDb() take a conservative approach - eLock is always updated
+** when unlocking the file, and only updated when locking the file if the
+** VFS call is successful. This way, the Pager.eLock variable may be set
+** to a less exclusive (lower) value than the lock that is actually held
+** at the system level, but it is never set to a more exclusive value.
+**
+** This is usually safe. If an xUnlock fails or appears to fail, there may 
+** be a few redundant xLock() calls or a lock may be held for longer than
+** required, but nothing really goes wrong.
+**
+** The exception is when the database file is unlocked as the pager moves
+** from ERROR to OPEN state. At this point there may be a hot-journal file 
+** in the file-system that needs to be rolled back (as part of a OPEN->SHARED
+** transition, by the same pager or any other). If the call to xUnlock()
+** fails at this point and the pager is left holding an EXCLUSIVE lock, this
+** can confuse the call to xCheckReservedLock() call made later as part
+** of hot-journal detection.
+**
+** xCheckReservedLock() is defined as returning true "if there is a RESERVED 
+** lock held by this process or any others". So xCheckReservedLock may 
+** return true because the caller itself is holding an EXCLUSIVE lock (but
+** doesn't know it because of a previous error in xUnlock). If this happens
+** a hot-journal may be mistaken for a journal being created by an active
+** transaction in another process, causing SQLite to read from the database
+** without rolling it back.
+**
+** To work around this, if a call to xUnlock() fails when unlocking the
+** database in the ERROR state, Pager.eLock is set to UNKNOWN_LOCK. It
+** is only changed back to a real locking state after a successful call
+** to xLock(EXCLUSIVE). Also, the code to do the OPEN->SHARED state transition
+** omits the check for a hot-journal if Pager.eLock is set to UNKNOWN_LOCK 
+** lock. Instead, it assumes a hot-journal exists and obtains an EXCLUSIVE
+** lock on the database file before attempting to roll it back. See function
+** PagerSharedLock() for more detail.
+**
+** Pager.eLock may only be set to UNKNOWN_LOCK when the pager is in 
+** PAGER_OPEN state.
+*/
+#define UNKNOWN_LOCK                (EXCLUSIVE_LOCK+1)
 
 /*
 ** A macro used for invoking the codec if there is one
@@ -33849,33 +35048,28 @@
 };
 
 /*
-** A open page cache is an instance of the following structure.
+** A open page cache is an instance of struct Pager. A description of
+** some of the more important member variables follows:
 **
-** errCode
+** eState
 **
-**   Pager.errCode may be set to SQLITE_IOERR, SQLITE_CORRUPT, or
-**   or SQLITE_FULL. Once one of the first three errors occurs, it persists
-**   and is returned as the result of every major pager API call.  The
-**   SQLITE_FULL return code is slightly different. It persists only until the
-**   next successful rollback is performed on the pager cache. Also,
-**   SQLITE_FULL does not affect the sqlite3PagerGet() and sqlite3PagerLookup()
-**   APIs, they may still be used successfully.
+**   The current 'state' of the pager object. See the comment and state
+**   diagram above for a description of the pager state.
 **
-** dbSizeValid, dbSize, dbOrigSize, dbFileSize
+** eLock
 **
-**   Managing the size of the database file in pages is a little complicated.
-**   The variable Pager.dbSize contains the number of pages that the database
-**   image currently contains. As the database image grows or shrinks this
-**   variable is updated. The variable Pager.dbFileSize contains the number
-**   of pages in the database file. This may be different from Pager.dbSize
-**   if some pages have been appended to the database image but not yet written
-**   out from the cache to the actual file on disk. Or if the image has been
-**   truncated by an incremental-vacuum operation. The Pager.dbOrigSize variable
-**   contains the number of pages in the database image when the current
-**   transaction was opened. The contents of all three of these variables is
-**   only guaranteed to be correct if the boolean Pager.dbSizeValid is true.
+**   For a real on-disk database, the current lock held on the database file -
+**   NO_LOCK, SHARED_LOCK, RESERVED_LOCK or EXCLUSIVE_LOCK.
 **
-**   TODO: Under what conditions is dbSizeValid set? Cleared?
+**   For a temporary or in-memory database (neither of which require any
+**   locks), this variable is always set to EXCLUSIVE_LOCK. Since such
+**   databases always have Pager.exclusiveMode==1, this tricks the pager
+**   logic into thinking that it already has all the locks it will ever
+**   need (and no reason to release them).
+**
+**   In some (obscure) circumstances, this variable may also be set to
+**   UNKNOWN_LOCK. See the comment above the #define of UNKNOWN_LOCK for
+**   details.
 **
 ** changeCountDone
 **
@@ -33894,67 +35088,123 @@
 **   need only update the change-counter once, for the first transaction
 **   committed.
 **
-** dbModified
-**
-**   The dbModified flag is set whenever a database page is dirtied.
-**   It is cleared at the end of each transaction.
-**
-**   It is used when committing or otherwise ending a transaction. If
-**   the dbModified flag is clear then less work has to be done.
-**
-** journalStarted
-**
-**   This flag is set whenever the the main journal is opened and
-**   initialized
-**
-**   The point of this flag is that it must be set after the 
-**   first journal header in a journal file has been synced to disk.
-**   After this has happened, new pages appended to the database 
-**   do not need the PGHDR_NEED_SYNC flag set, as they do not need
-**   to wait for a journal sync before they can be written out to
-**   the database file (see function pager_write()).
-**   
 ** setMaster
 **
-**   This variable is used to ensure that the master journal file name
-**   (if any) is only written into the journal file once.
+**   When PagerCommitPhaseOne() is called to commit a transaction, it may
+**   (or may not) specify a master-journal name to be written into the 
+**   journal file before it is synced to disk.
 **
-**   When committing a transaction, the master journal file name (if any)
-**   may be written into the journal file while the pager is still in
-**   PAGER_RESERVED state (see CommitPhaseOne() for the action). It
-**   then attempts to upgrade to an exclusive lock. If this attempt
-**   fails, then SQLITE_BUSY may be returned to the user and the user
-**   may attempt to commit the transaction again later (calling
-**   CommitPhaseOne() again). This flag is used to ensure that the 
-**   master journal name is only written to the journal file the first
-**   time CommitPhaseOne() is called.
+**   Whether or not a journal file contains a master-journal pointer affects 
+**   the way in which the journal file is finalized after the transaction is 
+**   committed or rolled back when running in "journal_mode=PERSIST" mode.
+**   If a journal file does not contain a master-journal pointer, it is
+**   finalized by overwriting the first journal header with zeroes. If
+**   it does contain a master-journal pointer the journal file is finalized 
+**   by truncating it to zero bytes, just as if the connection were 
+**   running in "journal_mode=truncate" mode.
+**
+**   Journal files that contain master journal pointers cannot be finalized
+**   simply by overwriting the first journal-header with zeroes, as the
+**   master journal pointer could interfere with hot-journal rollback of any
+**   subsequently interrupted transaction that reuses the journal file.
+**
+**   The flag is cleared as soon as the journal file is finalized (either
+**   by PagerCommitPhaseTwo or PagerRollback). If an IO error prevents the
+**   journal file from being successfully finalized, the setMaster flag
+**   is cleared anyway (and the pager will move to ERROR state).
 **
 ** doNotSpill, doNotSyncSpill
 **
-**   When enabled, cache spills are prohibited.  The doNotSpill variable
-**   inhibits all cache spill and doNotSyncSpill inhibits those spills that
-**   would require a journal sync.  The doNotSyncSpill is set and cleared 
-**   by sqlite3PagerWrite() in order to prevent a journal sync from happening 
-**   in between the journalling of two pages on the same sector.  The
-**   doNotSpill value set to prevent pagerStress() from trying to use
-**   the journal during a rollback.
+**   These two boolean variables control the behaviour of cache-spills
+**   (calls made by the pcache module to the pagerStress() routine to
+**   write cached data to the file-system in order to free up memory).
 **
-** needSync
-**
-**   TODO: It might be easier to set this variable in writeJournalHdr()
-**   and writeMasterJournal() only. Change its meaning to "unsynced data
-**   has been written to the journal".
+**   When doNotSpill is non-zero, writing to the database from pagerStress()
+**   is disabled altogether. This is done in a very obscure case that
+**   comes up during savepoint rollback that requires the pcache module
+**   to allocate a new page to prevent the journal file from being written
+**   while it is being traversed by code in pager_playback().
+** 
+**   If doNotSyncSpill is non-zero, writing to the database from pagerStress()
+**   is permitted, but syncing the journal file is not. This flag is set
+**   by sqlite3PagerWrite() when the file-system sector-size is larger than
+**   the database page-size in order to prevent a journal sync from happening 
+**   in between the journalling of two pages on the same sector. 
 **
 ** subjInMemory
 **
 **   This is a boolean variable. If true, then any required sub-journal
 **   is opened as an in-memory journal file. If false, then in-memory
 **   sub-journals are only used for in-memory pager files.
+**
+**   This variable is updated by the upper layer each time a new 
+**   write-transaction is opened.
+**
+** dbSize, dbOrigSize, dbFileSize
+**
+**   Variable dbSize is set to the number of pages in the database file.
+**   It is valid in PAGER_READER and higher states (all states except for
+**   OPEN and ERROR). 
+**
+**   dbSize is set based on the size of the database file, which may be 
+**   larger than the size of the database (the value stored at offset
+**   28 of the database header by the btree). If the size of the file
+**   is not an integer multiple of the page-size, the value stored in
+**   dbSize is rounded down (i.e. a 5KB file with 2K page-size has dbSize==2).
+**   Except, any file that is greater than 0 bytes in size is considered
+**   to have at least one page. (i.e. a 1KB file with 2K page-size leads
+**   to dbSize==1).
+**
+**   During a write-transaction, if pages with page-numbers greater than
+**   dbSize are modified in the cache, dbSize is updated accordingly.
+**   Similarly, if the database is truncated using PagerTruncateImage(), 
+**   dbSize is updated.
+**
+**   Variables dbOrigSize and dbFileSize are valid in states 
+**   PAGER_WRITER_LOCKED and higher. dbOrigSize is a copy of the dbSize
+**   variable at the start of the transaction. It is used during rollback,
+**   and to determine whether or not pages need to be journalled before
+**   being modified.
+**
+**   Throughout a write-transaction, dbFileSize contains the size of
+**   the file on disk in pages. It is set to a copy of dbSize when the
+**   write-transaction is first opened, and updated when VFS calls are made
+**   to write or truncate the database file on disk. 
+**
+**   The only reason the dbFileSize variable is required is to suppress 
+**   unnecessary calls to xTruncate() after committing a transaction. If, 
+**   when a transaction is committed, the dbFileSize variable indicates 
+**   that the database file is larger than the database image (Pager.dbSize), 
+**   pager_truncate() is called. The pager_truncate() call uses xFilesize()
+**   to measure the database file on disk, and then truncates it if required.
+**   dbFileSize is not used when rolling back a transaction. In this case
+**   pager_truncate() is called unconditionally (which means there may be
+**   a call to xFilesize() that is not strictly required). In either case,
+**   pager_truncate() may cause the file to become smaller or larger.
+**
+** dbHintSize
+**
+**   The dbHintSize variable is used to limit the number of calls made to
+**   the VFS xFileControl(FCNTL_SIZE_HINT) method. 
+**
+**   dbHintSize is set to a copy of the dbSize variable when a
+**   write-transaction is opened (at the same time as dbFileSize and
+**   dbOrigSize). If the xFileControl(FCNTL_SIZE_HINT) method is called,
+**   dbHintSize is increased to the number of pages that correspond to the
+**   size-hint passed to the method call. See pager_write_pagelist() for 
+**   details.
+**
+** errCode
+**
+**   The Pager.errCode variable is only ever used in PAGER_ERROR state. It
+**   is set to zero in all other states. In PAGER_ERROR state, Pager.errCode 
+**   is always set to SQLITE_FULL, SQLITE_IOERR or one of the SQLITE_IOERR_XXX 
+**   sub-codes.
 */
 struct Pager {
   sqlite3_vfs *pVfs;          /* OS functions to use for IO */
   u8 exclusiveMode;           /* Boolean. True if locking_mode==EXCLUSIVE */
-  u8 journalMode;             /* On of the PAGER_JOURNALMODE_* values */
+  u8 journalMode;             /* One of the PAGER_JOURNALMODE_* values */
   u8 useJournal;              /* Use a rollback journal on this file */
   u8 noReadlock;              /* Do not bother to obtain readlocks */
   u8 noSync;                  /* Do not sync the journal if true */
@@ -33964,30 +35214,26 @@
   u8 readOnly;                /* True for a read-only database */
   u8 memDb;                   /* True to inhibit all file I/O */
 
-  /* The following block contains those class members that are dynamically
-  ** modified during normal operations. The other variables in this structure
-  ** are either constant throughout the lifetime of the pager, or else
-  ** used to store configuration parameters that affect the way the pager 
-  ** operates.
-  **
-  ** The 'state' variable is described in more detail along with the
-  ** descriptions of the values it may take - PAGER_UNLOCK etc. Many of the
-  ** other variables in this block are described in the comment directly 
-  ** above this class definition.
+  /**************************************************************************
+  ** The following block contains those class members that change during
+  ** routine opertion.  Class members not in this block are either fixed
+  ** when the pager is first created or else only change when there is a
+  ** significant mode change (such as changing the page_size, locking_mode,
+  ** or the journal_mode).  From another view, these class members describe
+  ** the "state" of the pager, while other class members describe the
+  ** "configuration" of the pager.
   */
-  u8 state;                   /* PAGER_UNLOCK, _SHARED, _RESERVED, etc. */
-  u8 dbModified;              /* True if there are any changes to the Db */
-  u8 needSync;                /* True if an fsync() is needed on the journal */
-  u8 journalStarted;          /* True if header of journal is synced */
+  u8 eState;                  /* Pager state (OPEN, READER, WRITER_LOCKED..) */
+  u8 eLock;                   /* Current lock held on database file */
   u8 changeCountDone;         /* Set after incrementing the change-counter */
   u8 setMaster;               /* True if a m-j name has been written to jrnl */
   u8 doNotSpill;              /* Do not spill the cache when non-zero */
   u8 doNotSyncSpill;          /* Do not do a spill that requires jrnl sync */
-  u8 dbSizeValid;             /* Set when dbSize is correct */
   u8 subjInMemory;            /* True to use in-memory sub-journals */
   Pgno dbSize;                /* Number of pages in the database */
   Pgno dbOrigSize;            /* dbSize before the current transaction */
   Pgno dbFileSize;            /* Number of pages in the database file */
+  Pgno dbHintSize;            /* Value passed to FCNTL_SIZE_HINT call */
   int errCode;                /* One of several kinds of errors */
   int nRec;                   /* Pages journalled since last j-header written */
   u32 cksumInit;              /* Quasi-random value added to every checksum */
@@ -33998,17 +35244,21 @@
   sqlite3_file *sjfd;         /* File descriptor for sub-journal */
   i64 journalOff;             /* Current write offset in the journal file */
   i64 journalHdr;             /* Byte offset to previous journal header */
-  i64 journalSizeLimit;       /* Size limit for persistent journal files */
+  sqlite3_backup *pBackup;    /* Pointer to list of ongoing backup processes */
   PagerSavepoint *aSavepoint; /* Array of active savepoints */
   int nSavepoint;             /* Number of elements in aSavepoint[] */
   char dbFileVers[16];        /* Changes whenever database file changes */
-  u32 sectorSize;             /* Assumed sector size during rollback */
+  /*
+  ** End of the routinely-changing class members
+  ***************************************************************************/
 
   u16 nExtra;                 /* Add this many bytes to each in-memory page */
   i16 nReserve;               /* Number of unused bytes at end of each page */
   u32 vfsFlags;               /* Flags for sqlite3_vfs.xOpen() */
+  u32 sectorSize;             /* Assumed sector size during rollback */
   int pageSize;               /* Number of bytes in a page */
   Pgno mxPgno;                /* Maximum allowed size of the database */
+  i64 journalSizeLimit;       /* Size limit for persistent journal files */
   char *zFilename;            /* Name of the database file */
   char *zJournal;             /* Name of the journal file */
   int (*xBusyHandler)(void*); /* Function to call when busy */
@@ -34026,7 +35276,6 @@
 #endif
   char *pTmpSpace;            /* Pager.pageSize bytes of space for tmp use */
   PCache *pPCache;            /* Pointer to page cache object */
-  sqlite3_backup *pBackup;    /* Pointer to list of ongoing backup processes */
 #ifndef SQLITE_OMIT_WAL
   Wal *pWal;                  /* Write-ahead log used by "journal_mode=wal" */
   char *zWal;                 /* File name for write-ahead log */
@@ -34105,22 +35354,221 @@
 */
 #define PAGER_MAX_PGNO 2147483647
 
+/*
+** The argument to this macro is a file descriptor (type sqlite3_file*).
+** Return 0 if it is not open, or non-zero (but not 1) if it is.
+**
+** This is so that expressions can be written as:
+**
+**   if( isOpen(pPager->jfd) ){ ...
+**
+** instead of
+**
+**   if( pPager->jfd->pMethods ){ ...
+*/
+#define isOpen(pFd) ((pFd)->pMethods)
+
+/*
+** Return true if this pager uses a write-ahead log instead of the usual
+** rollback journal. Otherwise false.
+*/
+#ifndef SQLITE_OMIT_WAL
+static int pagerUseWal(Pager *pPager){
+  return (pPager->pWal!=0);
+}
+#else
+# define pagerUseWal(x) 0
+# define pagerRollbackWal(x) 0
+# define pagerWalFrames(v,w,x,y,z) 0
+# define pagerOpenWalIfPresent(z) SQLITE_OK
+# define pagerBeginReadTransaction(z) SQLITE_OK
+#endif
+
 #ifndef NDEBUG 
 /*
 ** Usage:
 **
 **   assert( assert_pager_state(pPager) );
+**
+** This function runs many asserts to try to find inconsistencies in
+** the internal state of the Pager object.
 */
-static int assert_pager_state(Pager *pPager){
+static int assert_pager_state(Pager *p){
+  Pager *pPager = p;
 
-  /* A temp-file is always in PAGER_EXCLUSIVE or PAGER_SYNCED state. */
-  assert( pPager->tempFile==0 || pPager->state>=PAGER_EXCLUSIVE );
+  /* State must be valid. */
+  assert( p->eState==PAGER_OPEN
+       || p->eState==PAGER_READER
+       || p->eState==PAGER_WRITER_LOCKED
+       || p->eState==PAGER_WRITER_CACHEMOD
+       || p->eState==PAGER_WRITER_DBMOD
+       || p->eState==PAGER_WRITER_FINISHED
+       || p->eState==PAGER_ERROR
+  );
 
-  /* The changeCountDone flag is always set for temp-files */
-  assert( pPager->tempFile==0 || pPager->changeCountDone );
+  /* Regardless of the current state, a temp-file connection always behaves
+  ** as if it has an exclusive lock on the database file. It never updates
+  ** the change-counter field, so the changeCountDone flag is always set.
+  */
+  assert( p->tempFile==0 || p->eLock==EXCLUSIVE_LOCK );
+  assert( p->tempFile==0 || pPager->changeCountDone );
+
+  /* If the useJournal flag is clear, the journal-mode must be "OFF". 
+  ** And if the journal-mode is "OFF", the journal file must not be open.
+  */
+  assert( p->journalMode==PAGER_JOURNALMODE_OFF || p->useJournal );
+  assert( p->journalMode!=PAGER_JOURNALMODE_OFF || !isOpen(p->jfd) );
+
+  /* Check that MEMDB implies noSync. And an in-memory journal. Since 
+  ** this means an in-memory pager performs no IO at all, it cannot encounter 
+  ** either SQLITE_IOERR or SQLITE_FULL during rollback or while finalizing 
+  ** a journal file. (although the in-memory journal implementation may 
+  ** return SQLITE_IOERR_NOMEM while the journal file is being written). It 
+  ** is therefore not possible for an in-memory pager to enter the ERROR 
+  ** state.
+  */
+  if( MEMDB ){
+    assert( p->noSync );
+    assert( p->journalMode==PAGER_JOURNALMODE_OFF 
+         || p->journalMode==PAGER_JOURNALMODE_MEMORY 
+    );
+    assert( p->eState!=PAGER_ERROR && p->eState!=PAGER_OPEN );
+    assert( pagerUseWal(p)==0 );
+  }
+
+  /* If changeCountDone is set, a RESERVED lock or greater must be held
+  ** on the file.
+  */
+  assert( pPager->changeCountDone==0 || pPager->eLock>=RESERVED_LOCK );
+  assert( p->eLock!=PENDING_LOCK );
+
+  switch( p->eState ){
+    case PAGER_OPEN:
+      assert( !MEMDB );
+      assert( pPager->errCode==SQLITE_OK );
+      assert( sqlite3PcacheRefCount(pPager->pPCache)==0 || pPager->tempFile );
+      break;
+
+    case PAGER_READER:
+      assert( pPager->errCode==SQLITE_OK );
+      assert( p->eLock!=UNKNOWN_LOCK );
+      assert( p->eLock>=SHARED_LOCK || p->noReadlock );
+      break;
+
+    case PAGER_WRITER_LOCKED:
+      assert( p->eLock!=UNKNOWN_LOCK );
+      assert( pPager->errCode==SQLITE_OK );
+      if( !pagerUseWal(pPager) ){
+        assert( p->eLock>=RESERVED_LOCK );
+      }
+      assert( pPager->dbSize==pPager->dbOrigSize );
+      assert( pPager->dbOrigSize==pPager->dbFileSize );
+      assert( pPager->dbOrigSize==pPager->dbHintSize );
+      assert( pPager->setMaster==0 );
+      break;
+
+    case PAGER_WRITER_CACHEMOD:
+      assert( p->eLock!=UNKNOWN_LOCK );
+      assert( pPager->errCode==SQLITE_OK );
+      if( !pagerUseWal(pPager) ){
+        /* It is possible that if journal_mode=wal here that neither the
+        ** journal file nor the WAL file are open. This happens during
+        ** a rollback transaction that switches from journal_mode=off
+        ** to journal_mode=wal.
+        */
+        assert( p->eLock>=RESERVED_LOCK );
+        assert( isOpen(p->jfd) 
+             || p->journalMode==PAGER_JOURNALMODE_OFF 
+             || p->journalMode==PAGER_JOURNALMODE_WAL 
+        );
+      }
+      assert( pPager->dbOrigSize==pPager->dbFileSize );
+      assert( pPager->dbOrigSize==pPager->dbHintSize );
+      break;
+
+    case PAGER_WRITER_DBMOD:
+      assert( p->eLock==EXCLUSIVE_LOCK );
+      assert( pPager->errCode==SQLITE_OK );
+      assert( !pagerUseWal(pPager) );
+      assert( p->eLock>=EXCLUSIVE_LOCK );
+      assert( isOpen(p->jfd) 
+           || p->journalMode==PAGER_JOURNALMODE_OFF 
+           || p->journalMode==PAGER_JOURNALMODE_WAL 
+      );
+      assert( pPager->dbOrigSize<=pPager->dbHintSize );
+      break;
+
+    case PAGER_WRITER_FINISHED:
+      assert( p->eLock==EXCLUSIVE_LOCK );
+      assert( pPager->errCode==SQLITE_OK );
+      assert( !pagerUseWal(pPager) );
+      assert( isOpen(p->jfd) 
+           || p->journalMode==PAGER_JOURNALMODE_OFF 
+           || p->journalMode==PAGER_JOURNALMODE_WAL 
+      );
+      break;
+
+    case PAGER_ERROR:
+      /* There must be at least one outstanding reference to the pager if
+      ** in ERROR state. Otherwise the pager should have already dropped
+      ** back to OPEN state.
+      */
+      assert( pPager->errCode!=SQLITE_OK );
+      assert( sqlite3PcacheRefCount(pPager->pPCache)>0 );
+      break;
+  }
 
   return 1;
 }
+
+/*
+** Return a pointer to a human readable string in a static buffer
+** containing the state of the Pager object passed as an argument. This
+** is intended to be used within debuggers. For example, as an alternative
+** to "print *pPager" in gdb:
+**
+** (gdb) printf "%s", print_pager_state(pPager)
+*/
+static char *print_pager_state(Pager *p){
+  static char zRet[1024];
+
+  sqlite3_snprintf(1024, zRet,
+      "Filename:      %s\n"
+      "State:         %s errCode=%d\n"
+      "Lock:          %s\n"
+      "Locking mode:  locking_mode=%s\n"
+      "Journal mode:  journal_mode=%s\n"
+      "Backing store: tempFile=%d memDb=%d useJournal=%d\n"
+      "Journal:       journalOff=%lld journalHdr=%lld\n"
+      "Size:          dbsize=%d dbOrigSize=%d dbFileSize=%d\n"
+      , p->zFilename
+      , p->eState==PAGER_OPEN            ? "OPEN" :
+        p->eState==PAGER_READER          ? "READER" :
+        p->eState==PAGER_WRITER_LOCKED   ? "WRITER_LOCKED" :
+        p->eState==PAGER_WRITER_CACHEMOD ? "WRITER_CACHEMOD" :
+        p->eState==PAGER_WRITER_DBMOD    ? "WRITER_DBMOD" :
+        p->eState==PAGER_WRITER_FINISHED ? "WRITER_FINISHED" :
+        p->eState==PAGER_ERROR           ? "ERROR" : "?error?"
+      , (int)p->errCode
+      , p->eLock==NO_LOCK         ? "NO_LOCK" :
+        p->eLock==RESERVED_LOCK   ? "RESERVED" :
+        p->eLock==EXCLUSIVE_LOCK  ? "EXCLUSIVE" :
+        p->eLock==SHARED_LOCK     ? "SHARED" :
+        p->eLock==UNKNOWN_LOCK    ? "UNKNOWN" : "?error?"
+      , p->exclusiveMode ? "exclusive" : "normal"
+      , p->journalMode==PAGER_JOURNALMODE_MEMORY   ? "memory" :
+        p->journalMode==PAGER_JOURNALMODE_OFF      ? "off" :
+        p->journalMode==PAGER_JOURNALMODE_DELETE   ? "delete" :
+        p->journalMode==PAGER_JOURNALMODE_PERSIST  ? "persist" :
+        p->journalMode==PAGER_JOURNALMODE_TRUNCATE ? "truncate" :
+        p->journalMode==PAGER_JOURNALMODE_WAL      ? "wal" : "?error?"
+      , (int)p->tempFile, (int)p->memDb, (int)p->useJournal
+      , p->journalOff, p->journalHdr
+      , (int)p->dbSize, (int)p->dbOrigSize, (int)p->dbFileSize
+  );
+
+  return zRet;
+}
 #endif
 
 /*
@@ -34173,6 +35621,7 @@
 */
 #define put32bits(A,B)  sqlite3Put4byte((u8*)A,B)
 
+
 /*
 ** Write a 32-bit integer into the given file descriptor.  Return SQLITE_OK
 ** on success or an error code is something goes wrong.
@@ -34184,27 +35633,53 @@
 }
 
 /*
-** The argument to this macro is a file descriptor (type sqlite3_file*).
-** Return 0 if it is not open, or non-zero (but not 1) if it is.
+** Unlock the database file to level eLock, which must be either NO_LOCK
+** or SHARED_LOCK. Regardless of whether or not the call to xUnlock()
+** succeeds, set the Pager.eLock variable to match the (attempted) new lock.
 **
-** This is so that expressions can be written as:
-**
-**   if( isOpen(pPager->jfd) ){ ...
-**
-** instead of
-**
-**   if( pPager->jfd->pMethods ){ ...
+** Except, if Pager.eLock is set to UNKNOWN_LOCK when this function is
+** called, do not modify it. See the comment above the #define of 
+** UNKNOWN_LOCK for an explanation of this.
 */
-#define isOpen(pFd) ((pFd)->pMethods)
+static int pagerUnlockDb(Pager *pPager, int eLock){
+  int rc = SQLITE_OK;
+
+  assert( !pPager->exclusiveMode );
+  assert( eLock==NO_LOCK || eLock==SHARED_LOCK );
+  assert( eLock!=NO_LOCK || pagerUseWal(pPager)==0 );
+  if( isOpen(pPager->fd) ){
+    assert( pPager->eLock>=eLock );
+    rc = sqlite3OsUnlock(pPager->fd, eLock);
+    if( pPager->eLock!=UNKNOWN_LOCK ){
+      pPager->eLock = (u8)eLock;
+    }
+    IOTRACE(("UNLOCK %p %d\n", pPager, eLock))
+  }
+  return rc;
+}
 
 /*
-** If file pFd is open, call sqlite3OsUnlock() on it.
+** Lock the database file to level eLock, which must be either SHARED_LOCK,
+** RESERVED_LOCK or EXCLUSIVE_LOCK. If the caller is successful, set the
+** Pager.eLock variable to the new locking state. 
+**
+** Except, if Pager.eLock is set to UNKNOWN_LOCK when this function is 
+** called, do not modify it unless the new locking state is EXCLUSIVE_LOCK. 
+** See the comment above the #define of UNKNOWN_LOCK for an explanation 
+** of this.
 */
-static int osUnlock(sqlite3_file *pFd, int eLock){
-  if( !isOpen(pFd) ){
-    return SQLITE_OK;
+static int pagerLockDb(Pager *pPager, int eLock){
+  int rc = SQLITE_OK;
+
+  assert( eLock==SHARED_LOCK || eLock==RESERVED_LOCK || eLock==EXCLUSIVE_LOCK );
+  if( pPager->eLock<eLock || pPager->eLock==UNKNOWN_LOCK ){
+    rc = sqlite3OsLock(pPager->fd, eLock);
+    if( rc==SQLITE_OK && (pPager->eLock!=UNKNOWN_LOCK||eLock==EXCLUSIVE_LOCK) ){
+      pPager->eLock = (u8)eLock;
+      IOTRACE(("LOCK %p %d\n", pPager, eLock))
+    }
   }
-  return sqlite3OsUnlock(pFd, eLock);
+  return rc;
 }
 
 /*
@@ -34280,13 +35755,14 @@
 #define CHECK_PAGE(x) checkPage(x)
 static void checkPage(PgHdr *pPg){
   Pager *pPager = pPg->pPager;
-  assert( !pPg->pageHash || pPager->errCode
-      || (pPg->flags&PGHDR_DIRTY) || pPg->pageHash==pager_pagehash(pPg) );
+  assert( pPager->eState!=PAGER_ERROR );
+  assert( (pPg->flags&PGHDR_DIRTY) || pPg->pageHash==pager_pagehash(pPg) );
 }
 
 #else
 #define pager_datahash(X,Y)  0
 #define pager_pagehash(X)  0
+#define pager_set_pagehash(X)
 #define CHECK_PAGE(x)
 #endif  /* SQLITE_CHECK_PAGES */
 
@@ -34453,7 +35929,7 @@
 static int writeJournalHdr(Pager *pPager){
   int rc = SQLITE_OK;                 /* Return code */
   char *zHeader = pPager->pTmpSpace;  /* Temporary space used to build header */
-  u32 nHeader = pPager->pageSize;     /* Size of buffer pointed to by zHeader */
+  u32 nHeader = (u32)pPager->pageSize;/* Size of buffer pointed to by zHeader */
   u32 nWrite;                         /* Bytes of header sector written */
   int ii;                             /* Loop counter */
 
@@ -34496,7 +35972,7 @@
   **     that garbage data is never appended to the journal file.
   */
   assert( isOpen(pPager->fd) || pPager->noSync );
-  if( (pPager->noSync) || (pPager->journalMode==PAGER_JOURNALMODE_MEMORY)
+  if( pPager->noSync || (pPager->journalMode==PAGER_JOURNALMODE_MEMORY)
    || (sqlite3OsDeviceCharacteristics(pPager->fd)&SQLITE_IOCAP_SAFE_APPEND) 
   ){
     memcpy(zHeader, aJournalMagic, sizeof(aJournalMagic));
@@ -34620,7 +36096,6 @@
   if( pPager->journalOff==0 ){
     u32 iPageSize;               /* Page-size field of journal header */
     u32 iSectorSize;             /* Sector-size field of journal header */
-    u16 iPageSize16;             /* Copy of iPageSize in 16-bit variable */
 
     /* Read the page-size and sector-size journal header fields. */
     if( SQLITE_OK!=(rc = read32bits(pPager->jfd, iHdrOff+20, &iSectorSize))
@@ -34629,6 +36104,14 @@
       return rc;
     }
 
+    /* Versions of SQLite prior to 3.5.8 set the page-size field of the
+    ** journal header to zero. In this case, assume that the Pager.pageSize
+    ** variable is already set to the correct page size.
+    */
+    if( iPageSize==0 ){
+      iPageSize = pPager->pageSize;
+    }
+
     /* Check that the values read from the page-size and sector-size fields
     ** are within range. To be 'in range', both values need to be a power
     ** of two greater than or equal to 512 or 32, and not greater than their 
@@ -34650,10 +36133,8 @@
     ** Use a testcase() macro to make sure that malloc failure within 
     ** PagerSetPagesize() is tested.
     */
-    iPageSize16 = (u16)iPageSize;
-    rc = sqlite3PagerSetPagesize(pPager, &iPageSize16, -1);
+    rc = sqlite3PagerSetPagesize(pPager, &iPageSize, -1);
     testcase( rc!=SQLITE_OK );
-    assert( rc!=SQLITE_OK || iPageSize16==(u16)iPageSize );
 
     /* Update the assumed sector-size to match the value used by 
     ** the process that created this journal. If this journal was
@@ -34695,7 +36176,10 @@
   i64 jrnlSize;                    /* Size of journal file on disk */
   u32 cksum = 0;                   /* Checksum of string zMaster */
 
-  if( !zMaster || pPager->setMaster
+  assert( pPager->setMaster==0 );
+  assert( !pagerUseWal(pPager) );
+
+  if( !zMaster 
    || pPager->journalMode==PAGER_JOURNALMODE_MEMORY 
    || pPager->journalMode==PAGER_JOURNALMODE_OFF 
   ){
@@ -34731,7 +36215,6 @@
     return rc;
   }
   pPager->journalOff += (nMaster+20);
-  pPager->needSync = !pPager->noSync;
 
   /* If the pager is in peristent-journal mode, then the physical 
   ** journal-file may extend past the end of the master-journal name
@@ -34767,17 +36250,11 @@
 }
 
 /*
-** Unless the pager is in error-state, discard all in-memory pages. If
-** the pager is in error-state, then this call is a no-op.
-**
-** TODO: Why can we not reset the pager while in error state?
+** Discard the entire contents of the in-memory page-cache.
 */
 static void pager_reset(Pager *pPager){
-  if( SQLITE_OK==pPager->errCode ){
-    sqlite3BackupRestart(pPager->pBackup);
-    sqlite3PcacheClear(pPager->pPCache);
-    pPager->dbSizeValid = 0;
-  }
+  sqlite3BackupRestart(pPager->pBackup);
+  sqlite3PcacheClear(pPager->pPCache);
 }
 
 /*
@@ -34820,34 +36297,39 @@
 }
 
 /*
-** Return true if this pager uses a write-ahead log instead of the usual
-** rollback journal. Otherwise false.
-*/
-#ifndef SQLITE_OMIT_WAL
-static int pagerUseWal(Pager *pPager){
-  return (pPager->pWal!=0);
-}
-#else
-# define pagerUseWal(x) 0
-# define pagerRollbackWal(x) 0
-# define pagerWalFrames(v,w,x,y,z) 0
-# define pagerOpenWalIfPresent(z) SQLITE_OK
-# define pagerBeginReadTransaction(z) SQLITE_OK
-#endif
-
-/*
-** Unlock the database file. This function is a no-op if the pager
-** is in exclusive mode.
+** This function is a no-op if the pager is in exclusive mode and not
+** in the ERROR state. Otherwise, it switches the pager to PAGER_OPEN
+** state.
 **
-** If the pager is currently in error state, discard the contents of 
-** the cache and reset the Pager structure internal state. If there is
-** an open journal-file, then the next time a shared-lock is obtained
-** on the pager file (by this or any other process), it will be
-** treated as a hot-journal and rolled back.
+** If the pager is not in exclusive-access mode, the database file is
+** completely unlocked. If the file is unlocked and the file-system does
+** not exhibit the UNDELETABLE_WHEN_OPEN property, the journal file is
+** closed (if it is open).
+**
+** If the pager is in ERROR state when this function is called, the 
+** contents of the pager cache are discarded before switching back to 
+** the OPEN state. Regardless of whether the pager is in exclusive-mode
+** or not, any journal file left in the file-system will be treated
+** as a hot-journal and rolled back the next time a read-transaction
+** is opened (by this or by any other connection).
 */
 static void pager_unlock(Pager *pPager){
-  if( !pPager->exclusiveMode ){
-    int rc = SQLITE_OK;          /* Return code */
+
+  assert( pPager->eState==PAGER_READER 
+       || pPager->eState==PAGER_OPEN 
+       || pPager->eState==PAGER_ERROR 
+  );
+
+  sqlite3BitvecDestroy(pPager->pInJournal);
+  pPager->pInJournal = 0;
+  releaseAllSavepoints(pPager);
+
+  if( pagerUseWal(pPager) ){
+    assert( !isOpen(pPager->jfd) );
+    sqlite3WalEndReadTransaction(pPager->pWal);
+    pPager->eState = PAGER_OPEN;
+  }else if( !pPager->exclusiveMode ){
+    int rc;                       /* Error code returned by pagerUnlockDb() */
     int iDc = isOpen(pPager->fd)?sqlite3OsDeviceCharacteristics(pPager->fd):0;
 
     /* If the operating system support deletion of open files, then
@@ -34867,58 +36349,56 @@
       sqlite3OsClose(pPager->jfd);
     }
 
-    sqlite3BitvecDestroy(pPager->pInJournal);
-    pPager->pInJournal = 0;
-    releaseAllSavepoints(pPager);
-
-    /* If the file is unlocked, somebody else might change it. The
-    ** values stored in Pager.dbSize etc. might become invalid if
-    ** this happens.  One can argue that this doesn't need to be cleared
-    ** until the change-counter check fails in PagerSharedLock().
-    ** Clearing the page size cache here is being conservative.
+    /* If the pager is in the ERROR state and the call to unlock the database
+    ** file fails, set the current lock to UNKNOWN_LOCK. See the comment
+    ** above the #define for UNKNOWN_LOCK for an explanation of why this
+    ** is necessary.
     */
-    pPager->dbSizeValid = 0;
-
-    if( pagerUseWal(pPager) ){
-      sqlite3WalEndReadTransaction(pPager->pWal);
-    }else{
-      rc = osUnlock(pPager->fd, NO_LOCK);
+    rc = pagerUnlockDb(pPager, NO_LOCK);
+    if( rc!=SQLITE_OK && pPager->eState==PAGER_ERROR ){
+      pPager->eLock = UNKNOWN_LOCK;
     }
-    if( rc ){
-      pPager->errCode = rc;
-    }
-    IOTRACE(("UNLOCK %p\n", pPager))
 
-    /* If Pager.errCode is set, the contents of the pager cache cannot be
-    ** trusted. Now that the pager file is unlocked, the contents of the
-    ** cache can be discarded and the error code safely cleared.
+    /* The pager state may be changed from PAGER_ERROR to PAGER_OPEN here
+    ** without clearing the error code. This is intentional - the error
+    ** code is cleared and the cache reset in the block below.
     */
-    if( pPager->errCode ){
-      if( rc==SQLITE_OK ){
-        pPager->errCode = SQLITE_OK;
-      }
-      pager_reset(pPager);
-    }
-
+    assert( pPager->errCode || pPager->eState!=PAGER_ERROR );
     pPager->changeCountDone = 0;
-    pPager->state = PAGER_UNLOCK;
-    pPager->dbModified = 0;
+    pPager->eState = PAGER_OPEN;
   }
+
+  /* If Pager.errCode is set, the contents of the pager cache cannot be
+  ** trusted. Now that there are no outstanding references to the pager,
+  ** it can safely move back to PAGER_OPEN state. This happens in both
+  ** normal and exclusive-locking mode.
+  */
+  if( pPager->errCode ){
+    assert( !MEMDB );
+    pager_reset(pPager);
+    pPager->changeCountDone = pPager->tempFile;
+    pPager->eState = PAGER_OPEN;
+    pPager->errCode = SQLITE_OK;
+  }
+
+  pPager->journalOff = 0;
+  pPager->journalHdr = 0;
+  pPager->setMaster = 0;
 }
 
 /*
-** This function should be called when an IOERR, CORRUPT or FULL error
-** may have occurred. The first argument is a pointer to the pager 
-** structure, the second the error-code about to be returned by a pager 
-** API function. The value returned is a copy of the second argument 
-** to this function. 
+** This function is called whenever an IOERR or FULL error that requires
+** the pager to transition into the ERROR state may ahve occurred.
+** The first argument is a pointer to the pager structure, the second 
+** the error-code about to be returned by a pager API function. The 
+** value returned is a copy of the second argument to this function. 
 **
-** If the second argument is SQLITE_IOERR, SQLITE_CORRUPT, or SQLITE_FULL
-** the error becomes persistent. Until the persistent error is cleared,
-** subsequent API calls on this Pager will immediately return the same 
-** error code.
+** If the second argument is SQLITE_FULL, SQLITE_IOERR or one of the
+** IOERR sub-codes, the pager enters the ERROR state and the error code
+** is stored in Pager.errCode. While the pager remains in the ERROR state,
+** all major API calls on the Pager will immediately return Pager.errCode.
 **
-** A persistent error indicates that the contents of the pager-cache 
+** The ERROR state indicates that the contents of the pager-cache 
 ** cannot be trusted. This state can be cleared by completely discarding 
 ** the contents of the pager-cache. If a transaction was active when
 ** the persistent error occurred, then the rollback journal may need
@@ -34935,45 +36415,21 @@
   );
   if( rc2==SQLITE_FULL || rc2==SQLITE_IOERR ){
     pPager->errCode = rc;
+    pPager->eState = PAGER_ERROR;
   }
   return rc;
 }
 
 /*
-** Execute a rollback if a transaction is active and unlock the 
-** database file. 
-**
-** If the pager has already entered the error state, do not attempt 
-** the rollback at this time. Instead, pager_unlock() is called. The
-** call to pager_unlock() will discard all in-memory pages, unlock
-** the database file and clear the error state. If this means that
-** there is a hot-journal left in the file-system, the next connection
-** to obtain a shared lock on the pager (which may be this one) will
-** roll it back.
-**
-** If the pager has not already entered the error state, but an IO or
-** malloc error occurs during a rollback, then this will itself cause 
-** the pager to enter the error state. Which will be cleared by the
-** call to pager_unlock(), as described above.
-*/
-static void pagerUnlockAndRollback(Pager *pPager){
-  if( pPager->errCode==SQLITE_OK && pPager->state>=PAGER_RESERVED ){
-    sqlite3BeginBenignMalloc();
-    sqlite3PagerRollback(pPager);
-    sqlite3EndBenignMalloc();
-  }
-  pager_unlock(pPager);
-}
-
-/*
 ** This routine ends a transaction. A transaction is usually ended by 
 ** either a COMMIT or a ROLLBACK operation. This routine may be called 
 ** after rollback of a hot-journal, or if an error occurs while opening
 ** the journal file or writing the very first journal-header of a
 ** database transaction.
 ** 
-** If the pager is in PAGER_SHARED or PAGER_UNLOCK state when this
-** routine is called, it is a no-op (returns SQLITE_OK).
+** This routine is never called in PAGER_ERROR state. If it is called
+** in PAGER_NONE or PAGER_SHARED state and the lock held is less
+** exclusive than a RESERVED lock, it is a no-op.
 **
 ** Otherwise, any active savepoints are released.
 **
@@ -35004,13 +36460,9 @@
 **     DELETE and the pager is in exclusive mode, the method described under
 **     journalMode==PERSIST is used instead.
 **
-** After the journal is finalized, if running in non-exclusive mode, the
-** pager moves to PAGER_SHARED state (and downgrades the lock on the
-** database file accordingly).
-**
-** If the pager is running in exclusive mode and is in PAGER_SYNCED state,
-** it moves to PAGER_EXCLUSIVE. No locks are downgraded when running in
-** exclusive mode.
+** After the journal is finalized, the pager moves to PAGER_READER state.
+** If running in non-exclusive rollback mode, the lock on the file is 
+** downgraded to a SHARED_LOCK.
 **
 ** SQLITE_OK is returned if no error occurs. If an error occurs during
 ** any of the IO operations to finalize the journal file or unlock the
@@ -35025,11 +36477,26 @@
   int rc = SQLITE_OK;      /* Error code from journal finalization operation */
   int rc2 = SQLITE_OK;     /* Error code from db file unlock operation */
 
-  if( pPager->state<PAGER_RESERVED ){
+  /* Do nothing if the pager does not have an open write transaction
+  ** or at least a RESERVED lock. This function may be called when there
+  ** is no write-transaction active but a RESERVED or greater lock is
+  ** held under two circumstances:
+  **
+  **   1. After a successful hot-journal rollback, it is called with
+  **      eState==PAGER_NONE and eLock==EXCLUSIVE_LOCK.
+  **
+  **   2. If a connection with locking_mode=exclusive holding an EXCLUSIVE 
+  **      lock switches back to locking_mode=normal and then executes a
+  **      read-transaction, this function is called with eState==PAGER_READER 
+  **      and eLock==EXCLUSIVE_LOCK when the read-transaction is closed.
+  */
+  assert( assert_pager_state(pPager) );
+  assert( pPager->eState!=PAGER_ERROR );
+  if( pPager->eState<PAGER_WRITER_LOCKED && pPager->eLock<RESERVED_LOCK ){
     return SQLITE_OK;
   }
-  releaseAllSavepoints(pPager);
 
+  releaseAllSavepoints(pPager);
   assert( isOpen(pPager->jfd) || pPager->pInJournal==0 );
   if( isOpen(pPager->jfd) ){
     assert( !pagerUseWal(pPager) );
@@ -35045,14 +36512,11 @@
         rc = sqlite3OsTruncate(pPager->jfd, 0);
       }
       pPager->journalOff = 0;
-      pPager->journalStarted = 0;
     }else if( pPager->journalMode==PAGER_JOURNALMODE_PERSIST
       || (pPager->exclusiveMode && pPager->journalMode!=PAGER_JOURNALMODE_WAL)
     ){
       rc = zeroJournalHdr(pPager, hasMaster);
-      pager_error(pPager, rc);
       pPager->journalOff = 0;
-      pPager->journalStarted = 0;
     }else{
       /* This branch may be executed with Pager.journalMode==MEMORY if
       ** a hot-journal was just rolled back. In this case the journal
@@ -35068,50 +36532,78 @@
         rc = sqlite3OsDelete(pPager->pVfs, pPager->zJournal, 0);
       }
     }
+  }
 
 #ifdef SQLITE_CHECK_PAGES
-    sqlite3PcacheIterateDirty(pPager->pPCache, pager_set_pagehash);
-#endif
+  sqlite3PcacheIterateDirty(pPager->pPCache, pager_set_pagehash);
+  if( pPager->dbSize==0 && sqlite3PcacheRefCount(pPager->pPCache)>0 ){
+    PgHdr *p = pager_lookup(pPager, 1);
+    if( p ){
+      p->pageHash = 0;
+      sqlite3PagerUnref(p);
+    }
   }
+#endif
+
   sqlite3BitvecDestroy(pPager->pInJournal);
   pPager->pInJournal = 0;
   pPager->nRec = 0;
   sqlite3PcacheCleanAll(pPager->pPCache);
+  sqlite3PcacheTruncate(pPager->pPCache, pPager->dbSize);
 
   if( pagerUseWal(pPager) ){
+    /* Drop the WAL write-lock, if any. Also, if the connection was in 
+    ** locking_mode=exclusive mode but is no longer, drop the EXCLUSIVE 
+    ** lock held on the database file.
+    */
     rc2 = sqlite3WalEndWriteTransaction(pPager->pWal);
     assert( rc2==SQLITE_OK );
-    pPager->state = PAGER_SHARED;
-
-    /* If the connection was in locking_mode=exclusive mode but is no longer,
-    ** drop the EXCLUSIVE lock held on the database file.
-    */
-    if( !pPager->exclusiveMode && sqlite3WalExclusiveMode(pPager->pWal, 0) ){
-      rc2 = osUnlock(pPager->fd, SHARED_LOCK);
-    }
-  }else if( !pPager->exclusiveMode ){
-    rc2 = osUnlock(pPager->fd, SHARED_LOCK);
-    pPager->state = PAGER_SHARED;
+  }
+  if( !pPager->exclusiveMode 
+   && (!pagerUseWal(pPager) || sqlite3WalExclusiveMode(pPager->pWal, 0))
+  ){
+    rc2 = pagerUnlockDb(pPager, SHARED_LOCK);
     pPager->changeCountDone = 0;
-  }else if( pPager->state==PAGER_SYNCED ){
-    pPager->state = PAGER_EXCLUSIVE;
   }
+  pPager->eState = PAGER_READER;
   pPager->setMaster = 0;
-  pPager->needSync = 0;
-  pPager->dbModified = 0;
-
-  /* TODO: Is this optimal? Why is the db size invalidated here 
-  ** when the database file is not unlocked? */
-  pPager->dbOrigSize = 0;
-  sqlite3PcacheTruncate(pPager->pPCache, pPager->dbSize);
-  if( !MEMDB ){
-    pPager->dbSizeValid = 0;
-  }
 
   return (rc==SQLITE_OK?rc2:rc);
 }
 
 /*
+** Execute a rollback if a transaction is active and unlock the 
+** database file. 
+**
+** If the pager has already entered the ERROR state, do not attempt 
+** the rollback at this time. Instead, pager_unlock() is called. The
+** call to pager_unlock() will discard all in-memory pages, unlock
+** the database file and move the pager back to OPEN state. If this 
+** means that there is a hot-journal left in the file-system, the next 
+** connection to obtain a shared lock on the pager (which may be this one) 
+** will roll it back.
+**
+** If the pager has not already entered the ERROR state, but an IO or
+** malloc error occurs during a rollback, then this will itself cause 
+** the pager to enter the ERROR state. Which will be cleared by the
+** call to pager_unlock(), as described above.
+*/
+static void pagerUnlockAndRollback(Pager *pPager){
+  if( pPager->eState!=PAGER_ERROR && pPager->eState!=PAGER_OPEN ){
+    assert( assert_pager_state(pPager) );
+    if( pPager->eState>=PAGER_WRITER_LOCKED ){
+      sqlite3BeginBenignMalloc();
+      sqlite3PagerRollback(pPager);
+      sqlite3EndBenignMalloc();
+    }else if( !pPager->exclusiveMode ){
+      assert( pPager->eState==PAGER_READER );
+      pager_end_transaction(pPager, 0);
+    }
+  }
+  pager_unlock(pPager);
+}
+
+/*
 ** Parameter aData must point to a buffer of pPager->pageSize bytes
 ** of data. Compute and return a checksum based ont the contents of the 
 ** page of data and the current value of pPager->cksumInit.
@@ -35161,9 +36653,8 @@
 ** The page begins at offset *pOffset into the file. The *pOffset
 ** value is increased to the start of the next page in the journal.
 **
-** The isMainJrnl flag is true if this is the main rollback journal and
-** false for the statement journal.  The main rollback journal uses
-** checksums - the statement journal does not.
+** The main rollback journal uses checksums - the statement journal does 
+** not.
 **
 ** If the page number of the page record read from the (sub-)journal file
 ** is greater than the current value of Pager.dbSize, then playback is
@@ -35217,6 +36708,17 @@
   assert( aData );         /* Temp storage must have already been allocated */
   assert( pagerUseWal(pPager)==0 || (!isMainJrnl && isSavepnt) );
 
+  /* Either the state is greater than PAGER_WRITER_CACHEMOD (a transaction 
+  ** or savepoint rollback done at the request of the caller) or this is
+  ** a hot-journal rollback. If it is a hot-journal rollback, the pager
+  ** is in state OPEN and holds an EXCLUSIVE lock. Hot-journal rollback
+  ** only reads from the main journal, not the sub-journal.
+  */
+  assert( pPager->eState>=PAGER_WRITER_CACHEMOD
+       || (pPager->eState==PAGER_OPEN && pPager->eLock==EXCLUSIVE_LOCK)
+  );
+  assert( pPager->eState>=PAGER_WRITER_CACHEMOD || isMainJrnl );
+
   /* Read the page number and page data from the journal or sub-journal
   ** file. Return an error code to the caller if an IO error occurs.
   */
@@ -35253,7 +36755,6 @@
   if( pDone && (rc = sqlite3BitvecSet(pDone, pgno))!=SQLITE_OK ){
     return rc;
   }
-  assert( pPager->state==PAGER_RESERVED || pPager->state>=PAGER_EXCLUSIVE );
 
   /* When playing back page 1, restore the nReserve setting
   */
@@ -35262,7 +36763,7 @@
     pagerReportSize(pPager);
   }
 
-  /* If the pager is in RESERVED state, then there must be a copy of this
+  /* If the pager is in CACHEMOD state, then there must be a copy of this
   ** page in the pager cache. In this case just update the pager cache,
   ** not the database file. The page is left marked dirty in this case.
   **
@@ -35273,8 +36774,11 @@
   ** either. So the condition described in the above paragraph is not
   ** assert()able.
   **
-  ** If in EXCLUSIVE state, then we update the pager cache if it exists
-  ** and the main file. The page is then marked not dirty.
+  ** If in WRITER_DBMOD, WRITER_FINISHED or OPEN state, then we update the
+  ** pager cache if it exists and the main file. The page is then marked 
+  ** not dirty. Since this code is only executed in PAGER_OPEN state for
+  ** a hot-journal rollback, it is guaranteed that the page-cache is empty
+  ** if the pager is in OPEN state.
   **
   ** Ticket #1171:  The statement journal might contain page content that is
   ** different from the page content at the start of the transaction.
@@ -35300,6 +36804,7 @@
     pPg = pager_lookup(pPager, pgno);
   }
   assert( pPg || !MEMDB );
+  assert( pPager->eState!=PAGER_OPEN || pPg==0 );
   PAGERTRACE(("PLAYBACK %d page %d hash(%08x) %s\n",
            PAGERID(pPager), pgno, pager_datahash(pPager->pageSize, (u8*)aData),
            (isMainJrnl?"main-journal":"sub-journal")
@@ -35309,8 +36814,8 @@
   }else{
     isSynced = (pPg==0 || 0==(pPg->flags & PGHDR_NEED_SYNC));
   }
-  if( (pPager->state>=PAGER_EXCLUSIVE)
-   && isOpen(pPager->fd)
+  if( isOpen(pPager->fd)
+   && (pPager->eState>=PAGER_WRITER_DBMOD || pPager->eState==PAGER_OPEN)
    && isSynced
   ){
     i64 ofst = (pgno-1)*(i64)pPager->pageSize;
@@ -35386,9 +36891,8 @@
       assert( !pagerUseWal(pPager) );
       sqlite3PcacheMakeClean(pPg);
     }
-#ifdef SQLITE_CHECK_PAGES
-    pPg->pageHash = pager_pagehash(pPg);
-#endif
+    pager_set_pagehash(pPg);
+
     /* If this was page 1, then restore the value of Pager.dbFileVers.
     ** Do this before any decoding. */
     if( pgno==1 ){
@@ -35540,10 +37044,10 @@
 ** file in the file-system. This only happens when committing a transaction,
 ** or rolling back a transaction (including rolling back a hot-journal).
 **
-** If the main database file is not open, or an exclusive lock is not
-** held, this function is a no-op. Otherwise, the size of the file is
-** changed to nPage pages (nPage*pPager->pageSize bytes). If the file
-** on disk is currently larger than nPage pages, then use the VFS
+** If the main database file is not open, or the pager is not in either
+** DBMOD or OPEN state, this function is a no-op. Otherwise, the size 
+** of the file is changed to nPage pages (nPage*pPager->pageSize bytes). 
+** If the file on disk is currently larger than nPage pages, then use the VFS
 ** xTruncate() method to truncate it.
 **
 ** Or, it might might be the case that the file on disk is smaller than 
@@ -35557,8 +37061,14 @@
 */
 static int pager_truncate(Pager *pPager, Pgno nPage){
   int rc = SQLITE_OK;
-  if( pPager->state>=PAGER_EXCLUSIVE && isOpen(pPager->fd) ){
+  assert( pPager->eState!=PAGER_ERROR );
+  assert( pPager->eState!=PAGER_READER );
+  
+  if( isOpen(pPager->fd) 
+   && (pPager->eState>=PAGER_WRITER_DBMOD || pPager->eState==PAGER_OPEN) 
+  ){
     i64 currentSize, newSize;
+    assert( pPager->eLock==EXCLUSIVE_LOCK );
     /* TODO: Is it safe to use Pager.dbFileSize here? */
     rc = sqlite3OsFileSize(pPager->fd, &currentSize);
     newSize = pPager->pageSize*(i64)nPage;
@@ -35682,7 +37192,7 @@
   */
   assert( isOpen(pPager->jfd) );
   rc = sqlite3OsFileSize(pPager->jfd, &szJ);
-  if( rc!=SQLITE_OK || szJ==0 ){
+  if( rc!=SQLITE_OK ){
     goto end_playback;
   }
 
@@ -35716,7 +37226,7 @@
   while( 1 ){
     /* Read the next journal header from the journal file.  If there are
     ** not enough bytes left in the journal file for a complete header, or
-    ** it is corrupted, then a process must of failed while writing it.
+    ** it is corrupted, then a process must have failed while writing it.
     ** This indicates nothing more needs to be rolled back.
     */
     rc = readJournalHdr(pPager, isHot, szJ, &nRec, &mxPg);
@@ -35830,10 +37340,9 @@
     rc = readMasterJournal(pPager->jfd, zMaster, pPager->pVfs->mxPathname+1);
     testcase( rc!=SQLITE_OK );
   }
-  if( rc==SQLITE_OK && pPager->noSync==0 && pPager->state>=PAGER_EXCLUSIVE ){
-    rc = sqlite3OsSync(pPager->fd, pPager->sync_flags);
-  }
-  if( rc==SQLITE_OK && pPager->noSync==0 && pPager->state>=PAGER_EXCLUSIVE ){
+  if( rc==SQLITE_OK && !pPager->noSync 
+   && (pPager->eState>=PAGER_WRITER_DBMOD || pPager->eState==PAGER_OPEN)
+  ){
     rc = sqlite3OsSync(pPager->fd, pPager->sync_flags);
   }
   if( rc==SQLITE_OK ){
@@ -35875,7 +37384,7 @@
   int isInWal = 0;             /* True if page is in log file */
   int pgsz = pPager->pageSize; /* Number of bytes to read */
 
-  assert( pPager->state>=PAGER_SHARED && !MEMDB );
+  assert( pPager->eState>=PAGER_READER && !MEMDB );
   assert( isOpen(pPager->fd) );
 
   if( NEVER(!isOpen(pPager->fd)) ){
@@ -36022,6 +37531,14 @@
       sqlite3BackupUpdate(pPager->pBackup, p->pgno, (u8 *)p->pData);
     }
   }
+
+#ifdef SQLITE_CHECK_PAGES
+  {
+    PgHdr *p;
+    for(p=pList; p; p=p->pDirty) pager_set_pagehash(p);
+  }
+#endif
+
   return rc;
 }
 
@@ -36038,6 +37555,7 @@
   int changed = 0;                /* True if cache must be reset */
 
   assert( pagerUseWal(pPager) );
+  assert( pPager->eState==PAGER_OPEN || pPager->eState==PAGER_READER );
 
   /* sqlite3WalEndReadTransaction() was not called for the previous
   ** transaction in locking_mode=EXCLUSIVE.  So call it now.  If we
@@ -36047,20 +37565,71 @@
   sqlite3WalEndReadTransaction(pPager->pWal);
 
   rc = sqlite3WalBeginReadTransaction(pPager->pWal, &changed);
-  if( rc==SQLITE_OK ){
-    int dummy;
-    if( changed ){
-      pager_reset(pPager);
-      assert( pPager->errCode || pPager->dbSizeValid==0 );
-    }
-    rc = sqlite3PagerPagecount(pPager, &dummy);
+  if( rc!=SQLITE_OK || changed ){
+    pager_reset(pPager);
   }
-  pPager->state = PAGER_SHARED;
 
   return rc;
 }
+#endif
 
 /*
+** This function is called as part of the transition from PAGER_OPEN
+** to PAGER_READER state to determine the size of the database file
+** in pages (assuming the page size currently stored in Pager.pageSize).
+**
+** If no error occurs, SQLITE_OK is returned and the size of the database
+** in pages is stored in *pnPage. Otherwise, an error code (perhaps
+** SQLITE_IOERR_FSTAT) is returned and *pnPage is left unmodified.
+*/
+static int pagerPagecount(Pager *pPager, Pgno *pnPage){
+  Pgno nPage;                     /* Value to return via *pnPage */
+
+  /* Query the WAL sub-system for the database size. The WalDbsize()
+  ** function returns zero if the WAL is not open (i.e. Pager.pWal==0), or
+  ** if the database size is not available. The database size is not
+  ** available from the WAL sub-system if the log file is empty or
+  ** contains no valid committed transactions.
+  */
+  assert( pPager->eState==PAGER_OPEN );
+  assert( pPager->eLock>=SHARED_LOCK || pPager->noReadlock );
+  nPage = sqlite3WalDbsize(pPager->pWal);
+
+  /* If the database size was not available from the WAL sub-system,
+  ** determine it based on the size of the database file. If the size
+  ** of the database file is not an integer multiple of the page-size,
+  ** round down to the nearest page. Except, any file larger than 0
+  ** bytes in size is considered to contain at least one page.
+  */
+  if( nPage==0 ){
+    i64 n = 0;                    /* Size of db file in bytes */
+    assert( isOpen(pPager->fd) || pPager->tempFile );
+    if( isOpen(pPager->fd) ){
+      int rc = sqlite3OsFileSize(pPager->fd, &n);
+      if( rc!=SQLITE_OK ){
+        return rc;
+      }
+    }
+    nPage = (Pgno)(n / pPager->pageSize);
+    if( nPage==0 && n>0 ){
+      nPage = 1;
+    }
+  }
+
+  /* If the current number of pages in the file is greater than the
+  ** configured maximum pager number, increase the allowed limit so
+  ** that the file can be read.
+  */
+  if( nPage>pPager->mxPgno ){
+    pPager->mxPgno = (Pgno)nPage;
+  }
+
+  *pnPage = nPage;
+  return SQLITE_OK;
+}
+
+#ifndef SQLITE_OMIT_WAL
+/*
 ** Check if the *-wal file that corresponds to the database opened by pPager
 ** exists if the database is not empy, or verify that the *-wal file does
 ** not exist (by deleting it) if the database file is empty.
@@ -36072,8 +37641,6 @@
 **
 ** Return SQLITE_OK or an error code.
 **
-** If the WAL file is opened, also open a snapshot (read transaction).
-**
 ** The caller must hold a SHARED lock on the database file to call this
 ** function. Because an EXCLUSIVE lock on the db file is required to delete 
 ** a WAL on a none-empty database, this ensures there is no race condition 
@@ -36082,11 +37649,14 @@
 */
 static int pagerOpenWalIfPresent(Pager *pPager){
   int rc = SQLITE_OK;
+  assert( pPager->eState==PAGER_OPEN );
+  assert( pPager->eLock>=SHARED_LOCK || pPager->noReadlock );
+
   if( !pPager->tempFile ){
     int isWal;                    /* True if WAL file exists */
-    int nPage;                    /* Size of the database file */
-    assert( pPager->state>=SHARED_LOCK );
-    rc = sqlite3PagerPagecount(pPager, &nPage);
+    Pgno nPage;                   /* Size of the database file */
+
+    rc = pagerPagecount(pPager, &nPage);
     if( rc ) return rc;
     if( nPage==0 ){
       rc = sqlite3OsDelete(pPager->pVfs, pPager->zWal, 0);
@@ -36098,11 +37668,8 @@
     }
     if( rc==SQLITE_OK ){
       if( isWal ){
-        pager_reset(pPager);
+        testcase( sqlite3PcachePagecount(pPager->pPCache)==0 );
         rc = sqlite3PagerOpenWal(pPager, 0);
-        if( rc==SQLITE_OK ){
-          rc = pagerBeginReadTransaction(pPager);
-        }
       }else if( pPager->journalMode==PAGER_JOURNALMODE_WAL ){
         pPager->journalMode = PAGER_JOURNALMODE_DELETE;
       }
@@ -36154,7 +37721,8 @@
   int rc = SQLITE_OK;      /* Return code */
   Bitvec *pDone = 0;       /* Bitvec to ensure pages played back only once */
 
-  assert( pPager->state>=PAGER_SHARED );
+  assert( pPager->eState!=PAGER_ERROR );
+  assert( pPager->eState>=PAGER_WRITER_LOCKED );
 
   /* Allocate a bitvec to use to store the set of pages rolled back */
   if( pSavepoint ){
@@ -36168,6 +37736,7 @@
   ** being reverted was opened.
   */
   pPager->dbSize = pSavepoint ? pSavepoint->nOrig : pPager->dbOrigSize;
+  pPager->changeCountDone = pPager->tempFile;
 
   if( !pSavepoint && pagerUseWal(pPager) ){
     return pagerRollbackWal(pPager);
@@ -36292,7 +37861,6 @@
   pPager->noSync =  (level==1 || pPager->tempFile) ?1:0;
   pPager->fullSync = (level==3 && !pPager->tempFile) ?1:0;
   pPager->sync_flags = (bFullFsync?SQLITE_SYNC_FULL:SQLITE_SYNC_NORMAL);
-  if( pPager->noSync ) pPager->needSync = 0;
 }
 #endif
 
@@ -36374,7 +37942,7 @@
 **
 ** If the pager is in the error state when this function is called, it
 ** is a no-op. The value returned is the error state error code (i.e. 
-** one of SQLITE_IOERR, SQLITE_CORRUPT or SQLITE_FULL).
+** one of SQLITE_IOERR, an SQLITE_IOERR_xxx sub-code or SQLITE_FULL).
 **
 ** Otherwise, if all of the following are true:
 **
@@ -36398,28 +37966,48 @@
 ** function was called, or because the memory allocation attempt failed, 
 ** then *pPageSize is set to the old, retained page size before returning.
 */
-SQLITE_PRIVATE int sqlite3PagerSetPagesize(Pager *pPager, u16 *pPageSize, int nReserve){
-  int rc = pPager->errCode;
+SQLITE_PRIVATE int sqlite3PagerSetPagesize(Pager *pPager, u32 *pPageSize, int nReserve){
+  int rc = SQLITE_OK;
 
-  if( rc==SQLITE_OK ){
-    u16 pageSize = *pPageSize;
-    assert( pageSize==0 || (pageSize>=512 && pageSize<=SQLITE_MAX_PAGE_SIZE) );
-    if( (pPager->memDb==0 || pPager->dbSize==0)
-     && sqlite3PcacheRefCount(pPager->pPCache)==0 
-     && pageSize && pageSize!=pPager->pageSize 
-    ){
-      char *pNew = (char *)sqlite3PageMalloc(pageSize);
-      if( !pNew ){
-        rc = SQLITE_NOMEM;
-      }else{
-        pager_reset(pPager);
-        pPager->pageSize = pageSize;
-        sqlite3PageFree(pPager->pTmpSpace);
-        pPager->pTmpSpace = pNew;
-        sqlite3PcacheSetPageSize(pPager->pPCache, pageSize);
-      }
+  /* It is not possible to do a full assert_pager_state() here, as this
+  ** function may be called from within PagerOpen(), before the state
+  ** of the Pager object is internally consistent.
+  **
+  ** At one point this function returned an error if the pager was in 
+  ** PAGER_ERROR state. But since PAGER_ERROR state guarantees that
+  ** there is at least one outstanding page reference, this function
+  ** is a no-op for that case anyhow.
+  */
+
+  u32 pageSize = *pPageSize;
+  assert( pageSize==0 || (pageSize>=512 && pageSize<=SQLITE_MAX_PAGE_SIZE) );
+  if( (pPager->memDb==0 || pPager->dbSize==0)
+   && sqlite3PcacheRefCount(pPager->pPCache)==0 
+   && pageSize && pageSize!=(u32)pPager->pageSize 
+  ){
+    char *pNew = NULL;             /* New temp space */
+    i64 nByte = 0;
+
+    if( pPager->eState>PAGER_OPEN && isOpen(pPager->fd) ){
+      rc = sqlite3OsFileSize(pPager->fd, &nByte);
     }
-    *pPageSize = (u16)pPager->pageSize;
+    if( rc==SQLITE_OK ){
+      pNew = (char *)sqlite3PageMalloc(pageSize);
+      if( !pNew ) rc = SQLITE_NOMEM;
+    }
+
+    if( rc==SQLITE_OK ){
+      pager_reset(pPager);
+      pPager->dbSize = (Pgno)(nByte/pageSize);
+      pPager->pageSize = pageSize;
+      sqlite3PageFree(pPager->pTmpSpace);
+      pPager->pTmpSpace = pNew;
+      sqlite3PcacheSetPageSize(pPager->pPCache, pageSize);
+    }
+  }
+
+  *pPageSize = pPager->pageSize;
+  if( rc==SQLITE_OK ){
     if( nReserve<0 ) nReserve = pPager->nReserve;
     assert( nReserve>=0 && nReserve<1000 );
     pPager->nReserve = (i16)nReserve;
@@ -36448,13 +38036,11 @@
 ** Regardless of mxPage, return the current maximum page count.
 */
 SQLITE_PRIVATE int sqlite3PagerMaxPageCount(Pager *pPager, int mxPage){
-  int nPage;
   if( mxPage>0 ){
     pPager->mxPgno = mxPage;
   }
-  if( pPager->state!=PAGER_UNLOCK ){
-    sqlite3PagerPagecount(pPager, &nPage);
-    assert( (int)pPager->mxPgno>=nPage );
+  if( pPager->eState!=PAGER_OPEN && pPager->mxPgno<pPager->dbSize ){
+    pPager->mxPgno = pPager->dbSize;
   }
   return pPager->mxPgno;
 }
@@ -36519,66 +38105,16 @@
 }
 
 /*
-** Return the total number of pages in the database file associated 
-** with pPager. Normally, this is calculated as (<db file size>/<page-size>).
+** This function may only be called when a read-transaction is open on
+** the pager. It returns the total number of pages in the database.
+**
 ** However, if the file is between 1 and <page-size> bytes in size, then 
 ** this is considered a 1 page file.
-**
-** If the pager is in error state when this function is called, then the
-** error state error code is returned and *pnPage left unchanged. Or,
-** if the file system has to be queried for the size of the file and
-** the query attempt returns an IO error, the IO error code is returned
-** and *pnPage is left unchanged.
-**
-** Otherwise, if everything is successful, then SQLITE_OK is returned
-** and *pnPage is set to the number of pages in the database.
 */
-SQLITE_PRIVATE int sqlite3PagerPagecount(Pager *pPager, int *pnPage){
-  Pgno nPage = 0;           /* Value to return via *pnPage */
-
-  /* Determine the number of pages in the file. Store this in nPage. */
-  if( pPager->dbSizeValid ){
-    nPage = pPager->dbSize;
-  }else{
-    int rc;                 /* Error returned by OsFileSize() */
-    i64 n = 0;              /* File size in bytes returned by OsFileSize() */
-
-    if( pagerUseWal(pPager) && pPager->state!=PAGER_UNLOCK ){
-      sqlite3WalDbsize(pPager->pWal, &nPage);
-    }
-
-    if( nPage==0 ){
-      assert( isOpen(pPager->fd) || pPager->tempFile );
-      if( isOpen(pPager->fd) ){
-        if( SQLITE_OK!=(rc = sqlite3OsFileSize(pPager->fd, &n)) ){
-          pager_error(pPager, rc);
-          return rc;
-        }
-      }
-      if( n>0 && n<pPager->pageSize ){
-        nPage = 1;
-      }else{
-        nPage = (Pgno)(n / pPager->pageSize);
-      }
-    }
-    if( pPager->state!=PAGER_UNLOCK ){
-      pPager->dbSize = nPage;
-      pPager->dbFileSize = nPage;
-      pPager->dbSizeValid = 1;
-    }
-  }
-
-  /* If the current number of pages in the file is greater than the 
-  ** configured maximum pager number, increase the allowed limit so
-  ** that the file can be read.
-  */
-  if( nPage>pPager->mxPgno ){
-    pPager->mxPgno = (Pgno)nPage;
-  }
-
-  /* Set the output variable and return SQLITE_OK */
-  *pnPage = nPage;
-  return SQLITE_OK;
+SQLITE_PRIVATE void sqlite3PagerPagecount(Pager *pPager, int *pnPage){
+  assert( pPager->eState>=PAGER_READER );
+  assert( pPager->eState!=PAGER_WRITER_FINISHED );
+  *pnPage = (int)pPager->dbSize;
 }
 
 
@@ -36599,38 +38135,19 @@
 static int pager_wait_on_lock(Pager *pPager, int locktype){
   int rc;                              /* Return code */
 
-  /* The OS lock values must be the same as the Pager lock values */
-  assert( PAGER_SHARED==SHARED_LOCK );
-  assert( PAGER_RESERVED==RESERVED_LOCK );
-  assert( PAGER_EXCLUSIVE==EXCLUSIVE_LOCK );
-
-  /* If the file is currently unlocked then the size must be unknown. It
-  ** must not have been modified at this point.
-  */
-  assert( pPager->state>=PAGER_SHARED || pPager->dbSizeValid==0 );
-  assert( pPager->state>=PAGER_SHARED || pPager->dbModified==0 );
-
   /* Check that this is either a no-op (because the requested lock is 
   ** already held, or one of the transistions that the busy-handler
   ** may be invoked during, according to the comment above
   ** sqlite3PagerSetBusyhandler().
   */
-  assert( (pPager->state>=locktype)
-       || (pPager->state==PAGER_UNLOCK && locktype==PAGER_SHARED)
-       || (pPager->state==PAGER_RESERVED && locktype==PAGER_EXCLUSIVE)
+  assert( (pPager->eLock>=locktype)
+       || (pPager->eLock==NO_LOCK && locktype==SHARED_LOCK)
+       || (pPager->eLock==RESERVED_LOCK && locktype==EXCLUSIVE_LOCK)
   );
 
-  if( pPager->state>=locktype ){
-    rc = SQLITE_OK;
-  }else{
-    do {
-      rc = sqlite3OsLock(pPager->fd, locktype);
-    }while( rc==SQLITE_BUSY && pPager->xBusyHandler(pPager->pBusyHandlerArg) );
-    if( rc==SQLITE_OK ){
-      pPager->state = (u8)locktype;
-      IOTRACE(("LOCK %p %d\n", pPager, locktype))
-    }
-  }
+  do {
+    rc = pagerLockDb(pPager, locktype);
+  }while( rc==SQLITE_BUSY && pPager->xBusyHandler(pPager->pBusyHandlerArg) );
   return rc;
 }
 
@@ -36675,9 +38192,8 @@
 ** truncation will be done when the current transaction is committed.
 */
 SQLITE_PRIVATE void sqlite3PagerTruncateImage(Pager *pPager, Pgno nPage){
-  assert( pPager->dbSizeValid );
   assert( pPager->dbSize>=nPage );
-  assert( pPager->state>=PAGER_RESERVED );
+  assert( pPager->eState>=PAGER_WRITER_CACHEMOD );
   pPager->dbSize = nPage;
   assertTruncateConstraint(pPager);
 }
@@ -36727,7 +38243,7 @@
 
   disable_simulated_io_errors();
   sqlite3BeginBenignMalloc();
-  pPager->errCode = 0;
+  /* pPager->errCode = 0; */
   pPager->exclusiveMode = 0;
 #ifndef SQLITE_OMIT_WAL
   sqlite3WalClose(pPager->pWal,
@@ -36740,14 +38256,19 @@
   if( MEMDB ){
     pager_unlock(pPager);
   }else{
-    /* Set Pager.journalHdr to -1 for the benefit of the pager_playback() 
-    ** call which may be made from within pagerUnlockAndRollback(). If it
-    ** is not -1, then the unsynced portion of an open journal file may
-    ** be played back into the database. If a power failure occurs while
-    ** this is happening, the database may become corrupt.
+    /* If it is open, sync the journal file before calling UnlockAndRollback.
+    ** If this is not done, then an unsynced portion of the open journal 
+    ** file may be played back into the database. If a power failure occurs 
+    ** while this is happening, the database could become corrupt.
+    **
+    ** If an error occurs while trying to sync the journal, shift the pager
+    ** into the ERROR state. This causes UnlockAndRollback to unlock the
+    ** database and close the journal file without attempting to roll it
+    ** back or finalize it. The next database user will have to do hot-journal
+    ** rollback before accessing the database file.
     */
     if( isOpen(pPager->jfd) ){
-      pPager->errCode = pagerSyncHotJournal(pPager);
+      pager_error(pPager, pagerSyncHotJournal(pPager));
     }
     pagerUnlockAndRollback(pPager);
   }
@@ -36792,9 +38313,9 @@
 ** been written to the journal have actually reached the surface of the
 ** disk and can be restored in the event of a hot-journal rollback.
 **
-** If the Pager.needSync flag is not set, then this function is a
-** no-op. Otherwise, the actions required depend on the journal-mode
-** and the device characteristics of the the file-system, as follows:
+** If the Pager.noSync flag is set, then this function is a no-op.
+** Otherwise, the actions required depend on the journal-mode and the 
+** device characteristics of the the file-system, as follows:
 **
 **   * If the journal file is an in-memory journal file, no action need
 **     be taken.
@@ -36818,18 +38339,25 @@
 **     if( NOT SEQUENTIAL ) xSync(<journal file>);
 **   }
 **
-** The Pager.needSync flag is never be set for temporary files, or any
-** file operating in no-sync mode (Pager.noSync set to non-zero).
-**
 ** If successful, this routine clears the PGHDR_NEED_SYNC flag of every 
 ** page currently held in memory before returning SQLITE_OK. If an IO
 ** error is encountered, then the IO error code is returned to the caller.
 */
-static int syncJournal(Pager *pPager){
-  if( pPager->needSync ){
+static int syncJournal(Pager *pPager, int newHdr){
+  int rc;                         /* Return code */
+
+  assert( pPager->eState==PAGER_WRITER_CACHEMOD
+       || pPager->eState==PAGER_WRITER_DBMOD
+  );
+  assert( assert_pager_state(pPager) );
+  assert( !pagerUseWal(pPager) );
+
+  rc = sqlite3PagerExclusiveLock(pPager);
+  if( rc!=SQLITE_OK ) return rc;
+
+  if( !pPager->noSync ){
     assert( !pPager->tempFile );
-    if( pPager->journalMode!=PAGER_JOURNALMODE_MEMORY ){
-      int rc;                              /* Return code */
+    if( isOpen(pPager->jfd) && pPager->journalMode!=PAGER_JOURNALMODE_MEMORY ){
       const int iDc = sqlite3OsDeviceCharacteristics(pPager->fd);
       assert( isOpen(pPager->jfd) );
 
@@ -36904,17 +38432,25 @@
         );
         if( rc!=SQLITE_OK ) return rc;
       }
-    }
 
-    /* The journal file was just successfully synced. Set Pager.needSync 
-    ** to zero and clear the PGHDR_NEED_SYNC flag on all pagess.
-    */
-    pPager->needSync = 0;
-    pPager->journalStarted = 1;
-    pPager->journalHdr = pPager->journalOff;
-    sqlite3PcacheClearSyncFlags(pPager->pPCache);
+      pPager->journalHdr = pPager->journalOff;
+      if( newHdr && 0==(iDc&SQLITE_IOCAP_SAFE_APPEND) ){
+        pPager->nRec = 0;
+        rc = writeJournalHdr(pPager);
+        if( rc!=SQLITE_OK ) return rc;
+      }
+    }else{
+      pPager->journalHdr = pPager->journalOff;
+    }
   }
 
+  /* Unless the pager is in noSync mode, the journal file was just 
+  ** successfully synced. Either way, clear the PGHDR_NEED_SYNC flag on 
+  ** all pages.
+  */
+  sqlite3PcacheClearSyncFlags(pPager->pPCache);
+  pPager->eState = PAGER_WRITER_DBMOD;
+  assert( assert_pager_state(pPager) );
   return SQLITE_OK;
 }
 
@@ -36951,27 +38487,12 @@
 ** be obtained, SQLITE_BUSY is returned.
 */
 static int pager_write_pagelist(Pager *pPager, PgHdr *pList){
-  int rc;                              /* Return code */
+  int rc = SQLITE_OK;                  /* Return code */
 
-  /* At this point there may be either a RESERVED or EXCLUSIVE lock on the
-  ** database file. If there is already an EXCLUSIVE lock, the following
-  ** call is a no-op.
-  **
-  ** Moving the lock from RESERVED to EXCLUSIVE actually involves going
-  ** through an intermediate state PENDING.   A PENDING lock prevents new
-  ** readers from attaching to the database but is unsufficient for us to
-  ** write.  The idea of a PENDING lock is to prevent new readers from
-  ** coming in while we wait for existing readers to clear.
-  **
-  ** While the pager is in the RESERVED state, the original database file
-  ** is unchanged and we can rollback without having to playback the
-  ** journal into the original database file.  Once we transition to
-  ** EXCLUSIVE, it means the database file has been changed and any rollback
-  ** will require a journal playback.
-  */
+  /* This function is only called for rollback pagers in WRITER_DBMOD state. */
   assert( !pagerUseWal(pPager) );
-  assert( pPager->state>=PAGER_RESERVED );
-  rc = pager_wait_on_lock(pPager, EXCLUSIVE_LOCK);
+  assert( pPager->eState==PAGER_WRITER_DBMOD );
+  assert( pPager->eLock==EXCLUSIVE_LOCK );
 
   /* If the file is a temp-file has not yet been opened, open it now. It
   ** is not possible for rc to be other than SQLITE_OK if this branch
@@ -36985,9 +38506,11 @@
   /* Before the first write, give the VFS a hint of what the final
   ** file size will be.
   */
-  if( pPager->dbSize > (pPager->dbOrigSize+1) && isOpen(pPager->fd) ){
+  assert( rc!=SQLITE_OK || isOpen(pPager->fd) );
+  if( rc==SQLITE_OK && pPager->dbSize>pPager->dbHintSize ){
     sqlite3_int64 szFile = pPager->pageSize * (sqlite3_int64)pPager->dbSize;
     sqlite3OsFileControl(pPager->fd, SQLITE_FCNTL_SIZE_HINT, &szFile);
+    pPager->dbHintSize = pPager->dbSize;
   }
 
   while( rc==SQLITE_OK && pList ){
@@ -37005,6 +38528,8 @@
       i64 offset = (pgno-1)*(i64)pPager->pageSize;   /* Offset to write */
       char *pData;                                   /* Data to write */    
 
+      assert( (pList->flags&PGHDR_NEED_SYNC)==0 );
+
       /* Encode the database */
       CODEC2(pPager, pList->pData, pgno, 6, return SQLITE_NOMEM, pData);
 
@@ -37033,9 +38558,7 @@
     }else{
       PAGERTRACE(("NOSTORE %d page %d\n", PAGERID(pPager), pgno));
     }
-#ifdef SQLITE_CHECK_PAGES
-    pList->pageHash = pager_pagehash(pList);
-#endif
+    pager_set_pagehash(pList);
     pList = pList->pDirty;
   }
 
@@ -37147,9 +38670,14 @@
   ** The doNotSpill flag inhibits all cache spilling regardless of whether
   ** or not a sync is required.  This is set during a rollback.
   **
-  ** Spilling is also inhibited when in an error state.
+  ** Spilling is also prohibited when in an error state since that could
+  ** lead to database corruption.   In the current implementaton it 
+  ** is impossible for sqlite3PCacheFetch() to be called with createFlag==1
+  ** while in the error state, hence it is impossible for this routine to
+  ** be called in the error state.  Nevertheless, we include a NEVER()
+  ** test for the error state as a safeguard against future changes.
   */
-  if( pPager->errCode ) return SQLITE_OK;
+  if( NEVER(pPager->errCode) ) return SQLITE_OK;
   if( pPager->doNotSpill ) return SQLITE_OK;
   if( pPager->doNotSyncSpill && (pPg->flags & PGHDR_NEED_SYNC)!=0 ){
     return SQLITE_OK;
@@ -37167,16 +38695,10 @@
   }else{
   
     /* Sync the journal file if required. */
-    if( pPg->flags&PGHDR_NEED_SYNC ){
-      assert( !pPager->noSync );
-      rc = syncJournal(pPager);
-      if( rc==SQLITE_OK && 
-        !(pPager->journalMode==PAGER_JOURNALMODE_MEMORY) &&
-        !(sqlite3OsDeviceCharacteristics(pPager->fd)&SQLITE_IOCAP_SAFE_APPEND)
-      ){
-        pPager->nRec = 0;
-        rc = writeJournalHdr(pPager);
-      }
+    if( pPg->flags&PGHDR_NEED_SYNC 
+     || pPager->eState==PAGER_WRITER_CACHEMOD
+    ){
+      rc = syncJournal(pPager, 1);
     }
   
     /* If the page number of this page is larger than the current size of
@@ -37214,6 +38736,7 @@
   
     /* Write the contents of the page out to the database file. */
     if( rc==SQLITE_OK ){
+      assert( (pPg->flags&PGHDR_NEED_SYNC)==0 );
       rc = pager_write_pagelist(pPager, pPg);
     }
   }
@@ -37224,7 +38747,7 @@
     sqlite3PcacheMakeClean(pPg);
   }
 
-  return pager_error(pPager, rc);
+  return pager_error(pPager, rc); 
 }
 
 
@@ -37279,7 +38802,7 @@
   int useJournal = (flags & PAGER_OMIT_JOURNAL)==0; /* False to omit journal */
   int noReadlock = (flags & PAGER_NO_READLOCK)!=0;  /* True to omit read-lock */
   int pcacheSize = sqlite3PcacheSize();       /* Bytes to allocate for PCache */
-  u16 szPageDflt = SQLITE_DEFAULT_PAGE_SIZE;  /* Default page size */
+  u32 szPageDflt = SQLITE_DEFAULT_PAGE_SIZE;  /* Default page size */
 
   /* Figure out how much space is required for each journal file-handle
   ** (there are two of them, the main journal and the sub-journal). This
@@ -37298,6 +38821,13 @@
   /* Set the output variable to NULL in case an error occurs. */
   *ppPager = 0;
 
+#ifndef SQLITE_OMIT_MEMORYDB
+  if( flags & PAGER_MEMORY ){
+    memDb = 1;
+    zFilename = 0;
+  }
+#endif
+
   /* Compute and store the full pathname in an allocated buffer pointed
   ** to by zPathname, length nPathname. Or, if this is a temporary file,
   ** leave both nPathname and zPathname set to 0.
@@ -37308,17 +38838,8 @@
     if( zPathname==0 ){
       return SQLITE_NOMEM;
     }
-#ifndef SQLITE_OMIT_MEMORYDB
-    if( strcmp(zFilename,":memory:")==0 ){
-      memDb = 1;
-      zPathname[0] = 0;
-    }else
-#endif
-    {
-      zPathname[0] = 0; /* Make sure initialized even if FullPathname() fails */
-      rc = sqlite3OsFullPathname(pVfs, zFilename, nPathname, zPathname);
-    }
-
+    zPathname[0] = 0; /* Make sure initialized even if FullPathname() fails */
+    rc = sqlite3OsFullPathname(pVfs, zFilename, nPathname, zPathname);
     nPathname = sqlite3Strlen30(zPathname);
     if( rc==SQLITE_OK && nPathname+8>pVfs->mxPathname ){
       /* This branch is taken when the journal path required by
@@ -37373,19 +38894,15 @@
 
   /* Fill in the Pager.zFilename and Pager.zJournal buffers, if required. */
   if( zPathname ){
+    assert( nPathname>0 );
     pPager->zJournal =   (char*)(pPtr += nPathname + 1);
     memcpy(pPager->zFilename, zPathname, nPathname);
     memcpy(pPager->zJournal, zPathname, nPathname);
     memcpy(&pPager->zJournal[nPathname], "-journal", 8);
-    if( pPager->zFilename[0]==0 ){
-      pPager->zJournal[0] = 0;
-    }
 #ifndef SQLITE_OMIT_WAL
-    else{
-      pPager->zWal = &pPager->zJournal[nPathname+8+1];
-      memcpy(pPager->zWal, zPathname, nPathname);
-      memcpy(&pPager->zWal[nPathname], "-wal", 4);
-    }
+    pPager->zWal = &pPager->zJournal[nPathname+8+1];
+    memcpy(pPager->zWal, zPathname, nPathname);
+    memcpy(&pPager->zWal[nPathname], "-wal", 4);
 #endif
     sqlite3_free(zPathname);
   }
@@ -37394,9 +38911,10 @@
 
   /* Open the pager file.
   */
-  if( zFilename && zFilename[0] && !memDb ){
+  if( zFilename && zFilename[0] ){
     int fout = 0;                    /* VFS flags returned by xOpen() */
     rc = sqlite3OsOpen(pVfs, pPager->zFilename, pPager->fd, vfsFlags, &fout);
+    assert( !memDb );
     readOnly = (fout&SQLITE_OPEN_READONLY);
 
     /* If the file was successfully opened for read/write access,
@@ -37414,7 +38932,7 @@
         if( pPager->sectorSize>SQLITE_MAX_DEFAULT_PAGE_SIZE ){
           szPageDflt = SQLITE_MAX_DEFAULT_PAGE_SIZE;
         }else{
-          szPageDflt = (u16)pPager->sectorSize;
+          szPageDflt = (u32)pPager->sectorSize;
         }
       }
 #ifdef SQLITE_ENABLE_ATOMIC_WRITE
@@ -37442,7 +38960,8 @@
     ** disk and uses an in-memory rollback journal.
     */ 
     tempFile = 1;
-    pPager->state = PAGER_EXCLUSIVE;
+    pPager->eState = PAGER_READER;
+    pPager->eLock = EXCLUSIVE_LOCK;
     readOnly = (vfsFlags&SQLITE_OPEN_READONLY);
   }
 
@@ -37479,13 +38998,14 @@
   /* pPager->stmtOpen = 0; */
   /* pPager->stmtInUse = 0; */
   /* pPager->nRef = 0; */
-  pPager->dbSizeValid = (u8)memDb;
   /* pPager->stmtSize = 0; */
   /* pPager->stmtJSize = 0; */
   /* pPager->nPage = 0; */
   pPager->mxPgno = SQLITE_MAX_PAGE_COUNT;
   /* pPager->state = PAGER_UNLOCK; */
+#if 0
   assert( pPager->state == (tempFile ? PAGER_EXCLUSIVE : PAGER_UNLOCK) );
+#endif
   /* pPager->errMask = 0; */
   pPager->tempFile = (u8)tempFile;
   assert( tempFile==PAGER_LOCKINGMODE_NORMAL 
@@ -37495,7 +39015,6 @@
   pPager->changeCountDone = pPager->tempFile;
   pPager->memDb = (u8)memDb;
   pPager->readOnly = (u8)readOnly;
-  /* pPager->needSync = 0; */
   assert( useJournal || pPager->tempFile );
   pPager->noSync = pPager->tempFile;
   pPager->fullSync = pPager->noSync ?0:1;
@@ -37560,10 +39079,10 @@
   int exists = 1;               /* True if a journal file is present */
   int jrnlOpen = !!isOpen(pPager->jfd);
 
-  assert( pPager!=0 );
   assert( pPager->useJournal );
   assert( isOpen(pPager->fd) );
-  assert( pPager->state <= PAGER_SHARED );
+  assert( pPager->eState==PAGER_OPEN );
+
   assert( jrnlOpen==0 || ( sqlite3OsDeviceCharacteristics(pPager->jfd) &
     SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN
   ));
@@ -37573,7 +39092,7 @@
     rc = sqlite3OsAccess(pVfs, pPager->zJournal, SQLITE_ACCESS_EXISTS, &exists);
   }
   if( rc==SQLITE_OK && exists ){
-    int locked;                 /* True if some process holds a RESERVED lock */
+    int locked = 0;             /* True if some process holds a RESERVED lock */
 
     /* Race condition here:  Another process might have been holding the
     ** the RESERVED lock and have a journal open at the sqlite3OsAccess() 
@@ -37585,7 +39104,7 @@
     */
     rc = sqlite3OsCheckReservedLock(pPager->fd, &locked);
     if( rc==SQLITE_OK && !locked ){
-      int nPage;
+      Pgno nPage;                 /* Number of pages in database file */
 
       /* Check the size of the database file. If it consists of 0 pages,
       ** then delete the journal file. See the header comment above for 
@@ -37593,13 +39112,13 @@
       ** a RESERVED lock to avoid race conditions and to avoid violating
       ** [H33020].
       */
-      rc = sqlite3PagerPagecount(pPager, &nPage);
+      rc = pagerPagecount(pPager, &nPage);
       if( rc==SQLITE_OK ){
         if( nPage==0 ){
           sqlite3BeginBenignMalloc();
-          if( sqlite3OsLock(pPager->fd, RESERVED_LOCK)==SQLITE_OK ){
+          if( pagerLockDb(pPager, RESERVED_LOCK)==SQLITE_OK ){
             sqlite3OsDelete(pVfs, pPager->zJournal, 0);
-            sqlite3OsUnlock(pPager->fd, SHARED_LOCK);
+            pagerUnlockDb(pPager, SHARED_LOCK);
           }
           sqlite3EndBenignMalloc();
         }else{
@@ -37652,7 +39171,7 @@
 **
 ** The following operations are also performed by this function.
 **
-**   1) If the pager is currently in PAGER_UNLOCK state (no lock held
+**   1) If the pager is currently in PAGER_OPEN state (no lock held
 **      on the database file), then an attempt is made to obtain a
 **      SHARED lock on the database file. Immediately after obtaining
 **      the SHARED lock, the file-system is checked for a hot-journal,
@@ -37667,66 +39186,47 @@
 **      the contents of the page cache and rolling back any open journal
 **      file.
 **
-** If the operation described by (2) above is not attempted, and if the
-** pager is in an error state other than SQLITE_FULL when this is called,
-** the error state error code is returned. It is permitted to read the
-** database when in SQLITE_FULL error state.
-**
-** Otherwise, if everything is successful, SQLITE_OK is returned. If an
-** IO error occurs while locking the database, checking for a hot-journal
-** file or rolling back a journal file, the IO error code is returned.
+** If everything is successful, SQLITE_OK is returned. If an IO error 
+** occurs while locking the database, checking for a hot-journal file or 
+** rolling back a journal file, the IO error code is returned.
 */
 SQLITE_PRIVATE int sqlite3PagerSharedLock(Pager *pPager){
   int rc = SQLITE_OK;                /* Return code */
-  int isErrorReset = 0;              /* True if recovering from error state */
 
   /* This routine is only called from b-tree and only when there are no
-  ** outstanding pages */
+  ** outstanding pages. This implies that the pager state should either
+  ** be OPEN or READER. READER is only possible if the pager is or was in 
+  ** exclusive access mode.
+  */
   assert( sqlite3PcacheRefCount(pPager->pPCache)==0 );
+  assert( assert_pager_state(pPager) );
+  assert( pPager->eState==PAGER_OPEN || pPager->eState==PAGER_READER );
   if( NEVER(MEMDB && pPager->errCode) ){ return pPager->errCode; }
 
-  /* If this database is in an error-state, now is a chance to clear
-  ** the error. Discard the contents of the pager-cache and rollback
-  ** any hot journal in the file-system.
-  */
-  if( pPager->errCode ){
-    if( isOpen(pPager->jfd) || pPager->zJournal ){
-      isErrorReset = 1;
-    }
-    pPager->errCode = SQLITE_OK;
-    pager_reset(pPager);
-  }
+  if( !pagerUseWal(pPager) && pPager->eState==PAGER_OPEN ){
+    int bHotJournal = 1;          /* True if there exists a hot journal-file */
 
-  if( pagerUseWal(pPager) ){
-    rc = pagerBeginReadTransaction(pPager);
-  }else if( pPager->state==PAGER_UNLOCK || isErrorReset ){
-    sqlite3_vfs * const pVfs = pPager->pVfs;
-    int isHotJournal = 0;
     assert( !MEMDB );
-    assert( sqlite3PcacheRefCount(pPager->pPCache)==0 );
-    if( pPager->noReadlock ){
-      assert( pPager->readOnly );
-      pPager->state = PAGER_SHARED;
-    }else{
+    assert( pPager->noReadlock==0 || pPager->readOnly );
+
+    if( pPager->noReadlock==0 ){
       rc = pager_wait_on_lock(pPager, SHARED_LOCK);
       if( rc!=SQLITE_OK ){
-        assert( pPager->state==PAGER_UNLOCK );
-        return pager_error(pPager, rc);
+        assert( pPager->eLock==NO_LOCK || pPager->eLock==UNKNOWN_LOCK );
+        goto failed;
       }
     }
-    assert( pPager->state>=SHARED_LOCK );
 
     /* If a journal file exists, and there is no RESERVED lock on the
     ** database file, then it either needs to be played back or deleted.
     */
-    if( !isErrorReset ){
-      assert( pPager->state <= PAGER_SHARED );
-      rc = hasHotJournal(pPager, &isHotJournal);
-      if( rc!=SQLITE_OK ){
-        goto failed;
-      }
+    if( pPager->eLock<=SHARED_LOCK ){
+      rc = hasHotJournal(pPager, &bHotJournal);
     }
-    if( isErrorReset || isHotJournal ){
+    if( rc!=SQLITE_OK ){
+      goto failed;
+    }
+    if( bHotJournal ){
       /* Get an EXCLUSIVE lock on the database file. At this point it is
       ** important that a RESERVED lock is not obtained on the way to the
       ** EXCLUSIVE lock. If it were, another process might open the
@@ -37738,58 +39238,45 @@
       ** other process attempting to access the database file will get to 
       ** this point in the code and fail to obtain its own EXCLUSIVE lock 
       ** on the database file.
+      **
+      ** Unless the pager is in locking_mode=exclusive mode, the lock is
+      ** downgraded to SHARED_LOCK before this function returns.
       */
-      if( pPager->state<EXCLUSIVE_LOCK ){
-        rc = sqlite3OsLock(pPager->fd, EXCLUSIVE_LOCK);
-        if( rc!=SQLITE_OK ){
-          rc = pager_error(pPager, rc);
-          goto failed;
-        }
-        pPager->state = PAGER_EXCLUSIVE;
-      }
- 
-      /* Open the journal for read/write access. This is because in 
-      ** exclusive-access mode the file descriptor will be kept open and
-      ** possibly used for a transaction later on. On some systems, the
-      ** OsTruncate() call used in exclusive-access mode also requires
-      ** a read/write file handle.
-      */
-      if( !isOpen(pPager->jfd) ){
-        int res;
-        rc = sqlite3OsAccess(pVfs,pPager->zJournal,SQLITE_ACCESS_EXISTS,&res);
-        if( rc==SQLITE_OK ){
-          if( res ){
-            int fout = 0;
-            int f = SQLITE_OPEN_READWRITE|SQLITE_OPEN_MAIN_JOURNAL;
-            assert( !pPager->tempFile );
-            rc = sqlite3OsOpen(pVfs, pPager->zJournal, pPager->jfd, f, &fout);
-            assert( rc!=SQLITE_OK || isOpen(pPager->jfd) );
-            if( rc==SQLITE_OK && fout&SQLITE_OPEN_READONLY ){
-              rc = SQLITE_CANTOPEN_BKPT;
-              sqlite3OsClose(pPager->jfd);
-            }
-          }else{
-            /* If the journal does not exist, it usually means that some 
-            ** other connection managed to get in and roll it back before 
-            ** this connection obtained the exclusive lock above. Or, it 
-            ** may mean that the pager was in the error-state when this
-            ** function was called and the journal file does not exist.  */
-            rc = pager_end_transaction(pPager, 0);
-          }
-        }
-      }
+      rc = pagerLockDb(pPager, EXCLUSIVE_LOCK);
       if( rc!=SQLITE_OK ){
         goto failed;
       }
-
-      /* Reset the journal status fields to indicates that we have no
-      ** rollback journal at this time. */
-      pPager->journalStarted = 0;
-      pPager->journalOff = 0;
-      pPager->setMaster = 0;
-      pPager->journalHdr = 0;
  
-      /* Make sure the journal file has been synced to disk. */
+      /* If it is not already open and the file exists on disk, open the 
+      ** journal for read/write access. Write access is required because 
+      ** in exclusive-access mode the file descriptor will be kept open 
+      ** and possibly used for a transaction later on. Also, write-access 
+      ** is usually required to finalize the journal in journal_mode=persist 
+      ** mode (and also for journal_mode=truncate on some systems).
+      **
+      ** If the journal does not exist, it usually means that some 
+      ** other connection managed to get in and roll it back before 
+      ** this connection obtained the exclusive lock above. Or, it 
+      ** may mean that the pager was in the error-state when this
+      ** function was called and the journal file does not exist.
+      */
+      if( !isOpen(pPager->jfd) ){
+        sqlite3_vfs * const pVfs = pPager->pVfs;
+        int bExists;              /* True if journal file exists */
+        rc = sqlite3OsAccess(
+            pVfs, pPager->zJournal, SQLITE_ACCESS_EXISTS, &bExists);
+        if( rc==SQLITE_OK && bExists ){
+          int fout = 0;
+          int f = SQLITE_OPEN_READWRITE|SQLITE_OPEN_MAIN_JOURNAL;
+          assert( !pPager->tempFile );
+          rc = sqlite3OsOpen(pVfs, pPager->zJournal, pPager->jfd, f, &fout);
+          assert( rc!=SQLITE_OK || isOpen(pPager->jfd) );
+          if( rc==SQLITE_OK && fout&SQLITE_OPEN_READONLY ){
+            rc = SQLITE_CANTOPEN_BKPT;
+            sqlite3OsClose(pPager->jfd);
+          }
+        }
+      }
  
       /* Playback and delete the journal.  Drop the database write
       ** lock and reacquire the read lock. Purge the cache before
@@ -37800,21 +39287,46 @@
       ** the journal before playing it back.
       */
       if( isOpen(pPager->jfd) ){
+        assert( rc==SQLITE_OK );
         rc = pagerSyncHotJournal(pPager);
         if( rc==SQLITE_OK ){
           rc = pager_playback(pPager, 1);
+          pPager->eState = PAGER_OPEN;
         }
-        if( rc!=SQLITE_OK ){
-          rc = pager_error(pPager, rc);
-          goto failed;
-        }
+      }else if( !pPager->exclusiveMode ){
+        pagerUnlockDb(pPager, SHARED_LOCK);
       }
-      assert( (pPager->state==PAGER_SHARED)
-           || (pPager->exclusiveMode && pPager->state>PAGER_SHARED)
+
+      if( rc!=SQLITE_OK ){
+        /* This branch is taken if an error occurs while trying to open
+        ** or roll back a hot-journal while holding an EXCLUSIVE lock. The
+        ** pager_unlock() routine will be called before returning to unlock
+        ** the file. If the unlock attempt fails, then Pager.eLock must be
+        ** set to UNKNOWN_LOCK (see the comment above the #define for 
+        ** UNKNOWN_LOCK above for an explanation). 
+        **
+        ** In order to get pager_unlock() to do this, set Pager.eState to
+        ** PAGER_ERROR now. This is not actually counted as a transition
+        ** to ERROR state in the state diagram at the top of this file,
+        ** since we know that the same call to pager_unlock() will very
+        ** shortly transition the pager object to the OPEN state. Calling
+        ** assert_pager_state() would fail now, as it should not be possible
+        ** to be in ERROR state when there are zero outstanding page 
+        ** references.
+        */
+        pager_error(pPager, rc);
+        goto failed;
+      }
+
+      assert( pPager->eState==PAGER_OPEN );
+      assert( (pPager->eLock==SHARED_LOCK)
+           || (pPager->exclusiveMode && pPager->eLock>SHARED_LOCK)
       );
     }
 
-    if( pPager->pBackup || sqlite3PcachePagecount(pPager->pPCache)>0 ){
+    if( !pPager->tempFile 
+     && (pPager->pBackup || sqlite3PcachePagecount(pPager->pPCache)>0) 
+    ){
       /* The shared-lock has just been acquired on the database file
       ** and there are already pages in the cache (from a previous
       ** read or write transaction).  Check to see if the database
@@ -37831,14 +39343,11 @@
       ** detected.  The chance of an undetected change is so small that
       ** it can be neglected.
       */
-      int nPage = 0;
+      Pgno nPage = 0;
       char dbFileVers[sizeof(pPager->dbFileVers)];
-      sqlite3PagerPagecount(pPager, &nPage);
 
-      if( pPager->errCode ){
-        rc = pPager->errCode;
-        goto failed;
-      }
+      rc = pagerPagecount(pPager, &nPage);
+      if( rc ) goto failed;
 
       if( nPage>0 ){
         IOTRACE(("CKVERS %p %d\n", pPager, sizeof(dbFileVers)));
@@ -37854,18 +39363,32 @@
         pager_reset(pPager);
       }
     }
-    assert( pPager->exclusiveMode || pPager->state==PAGER_SHARED );
 
     /* If there is a WAL file in the file-system, open this database in WAL
     ** mode. Otherwise, the following function call is a no-op.
     */
     rc = pagerOpenWalIfPresent(pPager);
+#ifndef SQLITE_OMIT_WAL
+    assert( pPager->pWal==0 || rc==SQLITE_OK );
+#endif
+  }
+
+  if( pagerUseWal(pPager) ){
+    assert( rc==SQLITE_OK );
+    rc = pagerBeginReadTransaction(pPager);
+  }
+
+  if( pPager->eState==PAGER_OPEN && rc==SQLITE_OK ){
+    rc = pagerPagecount(pPager, &pPager->dbSize);
   }
 
  failed:
   if( rc!=SQLITE_OK ){
-    /* pager_unlock() is a no-op for exclusive mode and in-memory databases. */
+    assert( !MEMDB );
     pager_unlock(pPager);
+    assert( pPager->eState==PAGER_OPEN );
+  }else{
+    pPager->eState = PAGER_READER;
   }
   return rc;
 }
@@ -37879,9 +39402,7 @@
 ** nothing to rollback, so this routine is a no-op.
 */ 
 static void pagerUnlockIfUnused(Pager *pPager){
-  if( (sqlite3PcacheRefCount(pPager->pPCache)==0)
-   && (!pPager->exclusiveMode || pPager->journalOff>0) 
-  ){
+  if( (sqlite3PcacheRefCount(pPager->pPCache)==0) ){
     pagerUnlockAndRollback(pPager);
   }
 }
@@ -37945,8 +39466,8 @@
   int rc;
   PgHdr *pPg;
 
+  assert( pPager->eState>=PAGER_READER );
   assert( assert_pager_state(pPager) );
-  assert( pPager->state>PAGER_UNLOCK );
 
   if( pgno==0 ){
     return SQLITE_CORRUPT_BKPT;
@@ -37954,7 +39475,7 @@
 
   /* If the pager is in the error state, return an error immediately. 
   ** Otherwise, request the page from the PCache layer. */
-  if( pPager->errCode!=SQLITE_OK && pPager->errCode!=SQLITE_FULL ){
+  if( pPager->errCode!=SQLITE_OK ){
     rc = pPager->errCode;
   }else{
     rc = sqlite3PcacheFetch(pPager->pPCache, pgno, 1, ppPage);
@@ -37980,7 +39501,6 @@
   }else{
     /* The pager cache has created a new page. Its content needs to 
     ** be initialized.  */
-    int nMax;
 
     PAGER_INCR(pPager->nMiss);
     pPg = *ppPage;
@@ -37993,12 +39513,7 @@
       goto pager_acquire_err;
     }
 
-    rc = sqlite3PagerPagecount(pPager, &nMax);
-    if( rc!=SQLITE_OK ){
-      goto pager_acquire_err;
-    }
-
-    if( MEMDB || nMax<(int)pgno || noContent || !isOpen(pPager->fd) ){
+    if( MEMDB || pPager->dbSize<pgno || noContent || !isOpen(pPager->fd) ){
       if( pgno>pPager->mxPgno ){
         rc = SQLITE_FULL;
         goto pager_acquire_err;
@@ -38028,9 +39543,7 @@
         goto pager_acquire_err;
       }
     }
-#ifdef SQLITE_CHECK_PAGES
-    pPg->pageHash = pager_pagehash(pPg);
-#endif
+    pager_set_pagehash(pPg);
   }
 
   return SQLITE_OK;
@@ -38049,9 +39562,7 @@
 /*
 ** Acquire a page if it is already in the in-memory cache.  Do
 ** not read the page from disk.  Return a pointer to the page,
-** or 0 if the page is not in cache. Also, return 0 if the 
-** pager is in PAGER_UNLOCK state when this function is called,
-** or if the pager is in an error state other than SQLITE_FULL.
+** or 0 if the page is not in cache. 
 **
 ** See also sqlite3PagerGet().  The difference between this routine
 ** and sqlite3PagerGet() is that _get() will go to the disk and read
@@ -38064,7 +39575,7 @@
   assert( pPager!=0 );
   assert( pgno!=0 );
   assert( pPager->pPCache!=0 );
-  assert( pPager->state > PAGER_UNLOCK );
+  assert( pPager->eState>=PAGER_READER && pPager->eState!=PAGER_ERROR );
   sqlite3PcacheFetch(pPager->pPCache, pgno, 0, &pPg);
   return pPg;
 }
@@ -38109,12 +39620,10 @@
 */
 static int pager_open_journal(Pager *pPager){
   int rc = SQLITE_OK;                        /* Return code */
-  int nPage;                                 /* Size of database file */
   sqlite3_vfs * const pVfs = pPager->pVfs;   /* Local cache of vfs pointer */
 
-  assert( pPager->state>=PAGER_RESERVED );
-  assert( pPager->useJournal );
-  assert( pPager->journalMode!=PAGER_JOURNALMODE_OFF );
+  assert( pPager->eState==PAGER_WRITER_LOCKED );
+  assert( assert_pager_state(pPager) );
   assert( pPager->pInJournal==0 );
   
   /* If already in the error state, this function is a no-op.  But on
@@ -38122,56 +39631,56 @@
   ** an error state. */
   if( NEVER(pPager->errCode) ) return pPager->errCode;
 
-  testcase( pPager->dbSizeValid==0 );
-  rc = sqlite3PagerPagecount(pPager, &nPage);
-  if( rc ) return rc;
-  pPager->pInJournal = sqlite3BitvecCreate(nPage);
-  if( pPager->pInJournal==0 ){
-    return SQLITE_NOMEM;
-  }
-
-  /* Open the journal file if it is not already open. */
-  if( !isOpen(pPager->jfd) ){
-    if( pPager->journalMode==PAGER_JOURNALMODE_MEMORY ){
-      sqlite3MemJournalOpen(pPager->jfd);
-    }else{
-      const int flags =                   /* VFS flags to open journal file */
-        SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE|
-        (pPager->tempFile ? 
-          (SQLITE_OPEN_DELETEONCLOSE|SQLITE_OPEN_TEMP_JOURNAL):
-          (SQLITE_OPEN_MAIN_JOURNAL)
-        );
-#ifdef SQLITE_ENABLE_ATOMIC_WRITE
-      rc = sqlite3JournalOpen(
-          pVfs, pPager->zJournal, pPager->jfd, flags, jrnlBufferSize(pPager)
-      );
-#else
-      rc = sqlite3OsOpen(pVfs, pPager->zJournal, pPager->jfd, flags, 0);
-#endif
+  if( !pagerUseWal(pPager) && pPager->journalMode!=PAGER_JOURNALMODE_OFF ){
+    pPager->pInJournal = sqlite3BitvecCreate(pPager->dbSize);
+    if( pPager->pInJournal==0 ){
+      return SQLITE_NOMEM;
     }
-    assert( rc!=SQLITE_OK || isOpen(pPager->jfd) );
-  }
-
-
-  /* Write the first journal header to the journal file and open 
-  ** the sub-journal if necessary.
-  */
-  if( rc==SQLITE_OK ){
-    /* TODO: Check if all of these are really required. */
-    pPager->dbOrigSize = pPager->dbSize;
-    pPager->journalStarted = 0;
-    pPager->needSync = 0;
-    pPager->nRec = 0;
-    pPager->journalOff = 0;
-    pPager->setMaster = 0;
-    pPager->journalHdr = 0;
-    rc = writeJournalHdr(pPager);
+  
+    /* Open the journal file if it is not already open. */
+    if( !isOpen(pPager->jfd) ){
+      if( pPager->journalMode==PAGER_JOURNALMODE_MEMORY ){
+        sqlite3MemJournalOpen(pPager->jfd);
+      }else{
+        const int flags =                   /* VFS flags to open journal file */
+          SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE|
+          (pPager->tempFile ? 
+            (SQLITE_OPEN_DELETEONCLOSE|SQLITE_OPEN_TEMP_JOURNAL):
+            (SQLITE_OPEN_MAIN_JOURNAL)
+          );
+  #ifdef SQLITE_ENABLE_ATOMIC_WRITE
+        rc = sqlite3JournalOpen(
+            pVfs, pPager->zJournal, pPager->jfd, flags, jrnlBufferSize(pPager)
+        );
+  #else
+        rc = sqlite3OsOpen(pVfs, pPager->zJournal, pPager->jfd, flags, 0);
+  #endif
+      }
+      assert( rc!=SQLITE_OK || isOpen(pPager->jfd) );
+    }
+  
+  
+    /* Write the first journal header to the journal file and open 
+    ** the sub-journal if necessary.
+    */
+    if( rc==SQLITE_OK ){
+      /* TODO: Check if all of these are really required. */
+      pPager->nRec = 0;
+      pPager->journalOff = 0;
+      pPager->setMaster = 0;
+      pPager->journalHdr = 0;
+      rc = writeJournalHdr(pPager);
+    }
   }
 
   if( rc!=SQLITE_OK ){
     sqlite3BitvecDestroy(pPager->pInJournal);
     pPager->pInJournal = 0;
+  }else{
+    assert( pPager->eState==PAGER_WRITER_LOCKED );
+    pPager->eState = PAGER_WRITER_CACHEMOD;
   }
+
   return rc;
 }
 
@@ -38184,14 +39693,6 @@
 ** an EXCLUSIVE lock. If such a lock is already held, no locking 
 ** functions need be called.
 **
-** If this is not a temporary or in-memory file and, the journal file is 
-** opened if it has not been already. For a temporary file, the opening 
-** of the journal file is deferred until there is an actual need to 
-** write to the journal. TODO: Why handle temporary files differently?
-**
-** If the journal file is opened (or if it is already open), then a
-** journal-header is written to the start of it.
-**
 ** If the subjInMemory argument is non-zero, then any sub-journal opened
 ** within this transaction will be opened as an in-memory file. This
 ** has no effect if the sub-journal is already opened (as it may be when
@@ -38202,20 +39703,20 @@
 */
 SQLITE_PRIVATE int sqlite3PagerBegin(Pager *pPager, int exFlag, int subjInMemory){
   int rc = SQLITE_OK;
-  assert( pPager->state!=PAGER_UNLOCK );
+
+  if( pPager->errCode ) return pPager->errCode;
+  assert( pPager->eState>=PAGER_READER && pPager->eState<PAGER_ERROR );
   pPager->subjInMemory = (u8)subjInMemory;
 
-  if( pPager->state==PAGER_SHARED ){
+  if( ALWAYS(pPager->eState==PAGER_READER) ){
     assert( pPager->pInJournal==0 );
-    assert( !MEMDB && !pPager->tempFile );
 
     if( pagerUseWal(pPager) ){
       /* If the pager is configured to use locking_mode=exclusive, and an
       ** exclusive lock on the database is not already held, obtain it now.
       */
       if( pPager->exclusiveMode && sqlite3WalExclusiveMode(pPager->pWal, -1) ){
-        rc = sqlite3OsLock(pPager->fd, EXCLUSIVE_LOCK);
-        pPager->state = PAGER_SHARED;
+        rc = pagerLockDb(pPager, EXCLUSIVE_LOCK);
         if( rc!=SQLITE_OK ){
           return rc;
         }
@@ -38226,52 +39727,40 @@
       ** PAGER_RESERVED state. Otherwise, return an error code to the caller.
       ** The busy-handler is not invoked if another connection already
       ** holds the write-lock. If possible, the upper layer will call it.
-      **
-      ** WAL mode sets Pager.state to PAGER_RESERVED when it has an open
-      ** transaction, but never to PAGER_EXCLUSIVE. This is because in 
-      ** PAGER_EXCLUSIVE state the code to roll back savepoint transactions
-      ** may copy data from the sub-journal into the database file as well
-      ** as into the page cache. Which would be incorrect in WAL mode.
       */
       rc = sqlite3WalBeginWriteTransaction(pPager->pWal);
-      if( rc==SQLITE_OK ){
-        pPager->dbOrigSize = pPager->dbSize;
-        pPager->state = PAGER_RESERVED;
-        pPager->journalOff = 0;
-      }
-
-      assert( rc!=SQLITE_OK || pPager->state==PAGER_RESERVED );
-      assert( rc==SQLITE_OK || pPager->state==PAGER_SHARED );
     }else{
       /* Obtain a RESERVED lock on the database file. If the exFlag parameter
       ** is true, then immediately upgrade this to an EXCLUSIVE lock. The
       ** busy-handler callback can be used when upgrading to the EXCLUSIVE
       ** lock, but not when obtaining the RESERVED lock.
       */
-      rc = sqlite3OsLock(pPager->fd, RESERVED_LOCK);
-      if( rc==SQLITE_OK ){
-        pPager->state = PAGER_RESERVED;
-        if( exFlag ){
-          rc = pager_wait_on_lock(pPager, EXCLUSIVE_LOCK);
-        }
+      rc = pagerLockDb(pPager, RESERVED_LOCK);
+      if( rc==SQLITE_OK && exFlag ){
+        rc = pager_wait_on_lock(pPager, EXCLUSIVE_LOCK);
       }
     }
 
-    /* No need to open the journal file at this time.  It will be
-    ** opened before it is written to.  If we defer opening the journal,
-    ** we might save the work of creating a file if the transaction
-    ** ends up being a no-op.
-    */
-
-    if( rc!=SQLITE_OK ){
-      assert( !pPager->dbModified );
-      /* Ignore any IO error that occurs within pager_end_transaction(). The
-      ** purpose of this call is to reset the internal state of the pager
-      ** sub-system. It doesn't matter if the journal-file is not properly
-      ** finalized at this point (since it is not a valid journal file anyway).
+    if( rc==SQLITE_OK ){
+      /* Change to WRITER_LOCKED state.
+      **
+      ** WAL mode sets Pager.eState to PAGER_WRITER_LOCKED or CACHEMOD
+      ** when it has an open transaction, but never to DBMOD or FINISHED.
+      ** This is because in those states the code to roll back savepoint 
+      ** transactions may copy data from the sub-journal into the database 
+      ** file as well as into the page cache. Which would be incorrect in 
+      ** WAL mode.
       */
-      pager_end_transaction(pPager, 0);
+      pPager->eState = PAGER_WRITER_LOCKED;
+      pPager->dbHintSize = pPager->dbSize;
+      pPager->dbFileSize = pPager->dbSize;
+      pPager->dbOrigSize = pPager->dbSize;
+      pPager->journalOff = 0;
     }
+
+    assert( rc==SQLITE_OK || pPager->eState==PAGER_READER );
+    assert( rc!=SQLITE_OK || pPager->eState==PAGER_WRITER_LOCKED );
+    assert( assert_pager_state(pPager) );
   }
 
   PAGERTRACE(("TRANSACTION %d\n", PAGERID(pPager)));
@@ -38290,22 +39779,24 @@
   Pager *pPager = pPg->pPager;
   int rc = SQLITE_OK;
 
-  /* This routine is not called unless a transaction has already been
-  ** started.
+  /* This routine is not called unless a write-transaction has already 
+  ** been started. The journal file may or may not be open at this point.
+  ** It is never called in the ERROR state.
   */
-  assert( pPager->state>=PAGER_RESERVED );
+  assert( pPager->eState==PAGER_WRITER_LOCKED
+       || pPager->eState==PAGER_WRITER_CACHEMOD
+       || pPager->eState==PAGER_WRITER_DBMOD
+  );
+  assert( assert_pager_state(pPager) );
 
   /* If an error has been previously detected, report the same error
-  ** again.
-  */
+  ** again. This should not happen, but the check provides robustness. */
   if( NEVER(pPager->errCode) )  return pPager->errCode;
 
   /* Higher-level routines never call this function if database is not
   ** writable.  But check anyway, just for robustness. */
   if( NEVER(pPager->readOnly) ) return SQLITE_PERM;
 
-  assert( !pPager->setMaster );
-
   CHECK_PAGE(pPg);
 
   /* Mark the page as dirty.  If the page has already been written
@@ -38314,56 +39805,60 @@
   sqlite3PcacheMakeDirty(pPg);
   if( pageInJournal(pPg) && !subjRequiresPage(pPg) ){
     assert( !pagerUseWal(pPager) );
-    pPager->dbModified = 1;
+    assert( pPager->eState>=PAGER_WRITER_CACHEMOD );
   }else{
 
     /* If we get this far, it means that the page needs to be
-    ** written to the transaction journal or the ckeckpoint journal
+    ** written to the transaction journal or the checkpoint journal
     ** or both.
     **
-    ** Higher level routines should have already started a transaction,
-    ** which means they have acquired the necessary locks but the rollback
-    ** journal might not yet be open.
+    ** Higher level routines have already obtained the necessary locks
+    ** to begin the write-transaction, but the rollback journal might not 
+    ** yet be open. Open it now if this is the case.
     */
-    assert( pPager->state>=RESERVED_LOCK );
-    if( pPager->pInJournal==0
-     && pPager->journalMode!=PAGER_JOURNALMODE_OFF 
-     && !pagerUseWal(pPager)
-    ){
-      assert( pPager->useJournal );
+    if( pPager->eState==PAGER_WRITER_LOCKED ){
       rc = pager_open_journal(pPager);
       if( rc!=SQLITE_OK ) return rc;
     }
-    pPager->dbModified = 1;
+    assert( pPager->eState>=PAGER_WRITER_CACHEMOD );
+    assert( assert_pager_state(pPager) );
   
     /* The transaction journal now exists and we have a RESERVED or an
     ** EXCLUSIVE lock on the main database file.  Write the current page to
     ** the transaction journal if it is not there already.
     */
-    if( !pageInJournal(pPg) && isOpen(pPager->jfd) ){
-      assert( !pagerUseWal(pPager) );
-      if( pPg->pgno<=pPager->dbOrigSize ){
+    if( !pageInJournal(pPg) && !pagerUseWal(pPager) ){
+      assert( pagerUseWal(pPager)==0 );
+      if( pPg->pgno<=pPager->dbOrigSize && isOpen(pPager->jfd) ){
         u32 cksum;
         char *pData2;
+        i64 iOff = pPager->journalOff;
 
         /* We should never write to the journal file the page that
         ** contains the database locks.  The following assert verifies
         ** that we do not. */
         assert( pPg->pgno!=PAGER_MJ_PGNO(pPager) );
 
-        assert( pPager->journalHdr <= pPager->journalOff );
+        assert( pPager->journalHdr<=pPager->journalOff );
         CODEC2(pPager, pData, pPg->pgno, 7, return SQLITE_NOMEM, pData2);
         cksum = pager_cksum(pPager, (u8*)pData2);
-        rc = write32bits(pPager->jfd, pPager->journalOff, pPg->pgno);
-        if( rc==SQLITE_OK ){
-          rc = sqlite3OsWrite(pPager->jfd, pData2, pPager->pageSize,
-                              pPager->journalOff + 4);
-          pPager->journalOff += pPager->pageSize+4;
-        }
-        if( rc==SQLITE_OK ){
-          rc = write32bits(pPager->jfd, pPager->journalOff, cksum);
-          pPager->journalOff += 4;
-        }
+
+        /* Even if an IO or diskfull error occurs while journalling the
+        ** page in the block above, set the need-sync flag for the page.
+        ** Otherwise, when the transaction is rolled back, the logic in
+        ** playback_one_page() will think that the page needs to be restored
+        ** in the database file. And if an IO error occurs while doing so,
+        ** then corruption may follow.
+        */
+        pPg->flags |= PGHDR_NEED_SYNC;
+
+        rc = write32bits(pPager->jfd, iOff, pPg->pgno);
+        if( rc!=SQLITE_OK ) return rc;
+        rc = sqlite3OsWrite(pPager->jfd, pData2, pPager->pageSize, iOff+4);
+        if( rc!=SQLITE_OK ) return rc;
+        rc = write32bits(pPager->jfd, iOff+pPager->pageSize+4, cksum);
+        if( rc!=SQLITE_OK ) return rc;
+
         IOTRACE(("JOUT %p %d %lld %d\n", pPager, pPg->pgno, 
                  pPager->journalOff, pPager->pageSize));
         PAGER_INCR(sqlite3_pager_writej_count);
@@ -38371,25 +39866,7 @@
              PAGERID(pPager), pPg->pgno, 
              ((pPg->flags&PGHDR_NEED_SYNC)?1:0), pager_pagehash(pPg)));
 
-        /* Even if an IO or diskfull error occurred while journalling the
-        ** page in the block above, set the need-sync flag for the page.
-        ** Otherwise, when the transaction is rolled back, the logic in
-        ** playback_one_page() will think that the page needs to be restored
-        ** in the database file. And if an IO error occurs while doing so,
-        ** then corruption may follow.
-        */
-        if( !pPager->noSync ){
-          pPg->flags |= PGHDR_NEED_SYNC;
-          pPager->needSync = 1;
-        }
-
-        /* An error has occurred writing to the journal file. The 
-        ** transaction will be rolled back by the layer above.
-        */
-        if( rc!=SQLITE_OK ){
-          return rc;
-        }
-
+        pPager->journalOff += 8 + pPager->pageSize;
         pPager->nRec++;
         assert( pPager->pInJournal!=0 );
         rc = sqlite3BitvecSet(pPager->pInJournal, pPg->pgno);
@@ -38401,9 +39878,8 @@
           return rc;
         }
       }else{
-        if( !pPager->journalStarted && !pPager->noSync ){
+        if( pPager->eState!=PAGER_WRITER_DBMOD ){
           pPg->flags |= PGHDR_NEED_SYNC;
-          pPager->needSync = 1;
         }
         PAGERTRACE(("APPEND %d page %d needSync=%d\n",
                 PAGERID(pPager), pPg->pgno,
@@ -38423,7 +39899,6 @@
 
   /* Update the database size and return.
   */
-  assert( pPager->state>=PAGER_SHARED );
   if( pPager->dbSize<pPg->pgno ){
     pPager->dbSize = pPg->pgno;
   }
@@ -38451,6 +39926,10 @@
   Pager *pPager = pPg->pPager;
   Pgno nPagePerSector = (pPager->sectorSize/pPager->pageSize);
 
+  assert( pPager->eState>=PAGER_WRITER_LOCKED );
+  assert( pPager->eState!=PAGER_ERROR );
+  assert( assert_pager_state(pPager) );
+
   if( nPagePerSector>1 ){
     Pgno nPageCount;          /* Total number of pages in database file */
     Pgno pg1;                 /* First page of the sector pPg is located on. */
@@ -38472,19 +39951,17 @@
     */
     pg1 = ((pPg->pgno-1) & ~(nPagePerSector-1)) + 1;
 
-    rc = sqlite3PagerPagecount(pPager, (int *)&nPageCount);
-    if( rc==SQLITE_OK ){
-      if( pPg->pgno>nPageCount ){
-        nPage = (pPg->pgno - pg1)+1;
-      }else if( (pg1+nPagePerSector-1)>nPageCount ){
-        nPage = nPageCount+1-pg1;
-      }else{
-        nPage = nPagePerSector;
-      }
-      assert(nPage>0);
-      assert(pg1<=pPg->pgno);
-      assert((pg1+nPage)>pPg->pgno);
+    nPageCount = pPager->dbSize;
+    if( pPg->pgno>nPageCount ){
+      nPage = (pPg->pgno - pg1)+1;
+    }else if( (pg1+nPagePerSector-1)>nPageCount ){
+      nPage = nPageCount+1-pg1;
+    }else{
+      nPage = nPagePerSector;
     }
+    assert(nPage>0);
+    assert(pg1<=pPg->pgno);
+    assert((pg1+nPage)>pPg->pgno);
 
     for(ii=0; ii<nPage && rc==SQLITE_OK; ii++){
       Pgno pg = pg1+ii;
@@ -38496,7 +39973,6 @@
             rc = pager_write(pPage);
             if( pPage->flags&PGHDR_NEED_SYNC ){
               needSync = 1;
-              assert(pPager->needSync);
             }
             sqlite3PagerUnref(pPage);
           }
@@ -38516,7 +39992,7 @@
     ** before any of them can be written out to the database file.
     */
     if( rc==SQLITE_OK && needSync ){
-      assert( !MEMDB && pPager->noSync==0 );
+      assert( !MEMDB );
       for(ii=0; ii<nPage; ii++){
         PgHdr *pPage = pager_lookup(pPager, pg1+ii);
         if( pPage ){
@@ -38524,7 +40000,6 @@
           sqlite3PagerUnref(pPage);
         }
       }
-      assert(pPager->needSync);
     }
 
     assert( pPager->doNotSyncSpill==1 );
@@ -38566,9 +40041,7 @@
     PAGERTRACE(("DONT_WRITE page %d of %d\n", pPg->pgno, PAGERID(pPager)));
     IOTRACE(("CLEAN %p %d\n", pPager, pPg->pgno))
     pPg->flags |= PGHDR_DONT_WRITE;
-#ifdef SQLITE_CHECK_PAGES
-    pPg->pageHash = pager_pagehash(pPg);
-#endif
+    pager_set_pagehash(pPg);
   }
 }
 
@@ -38591,6 +40064,11 @@
 static int pager_incr_changecounter(Pager *pPager, int isDirectMode){
   int rc = SQLITE_OK;
 
+  assert( pPager->eState==PAGER_WRITER_CACHEMOD
+       || pPager->eState==PAGER_WRITER_DBMOD
+  );
+  assert( assert_pager_state(pPager) );
+
   /* Declare and initialize constant integer 'isDirect'. If the
   ** atomic-write optimization is enabled in this build, then isDirect
   ** is initialized to the value passed as the isDirectMode parameter
@@ -38609,7 +40087,6 @@
 # define DIRECT_MODE isDirectMode
 #endif
 
-  assert( pPager->state>=PAGER_RESERVED );
   if( !pPager->changeCountDone && pPager->dbSize>0 ){
     PgHdr *pPgHdr;                /* Reference to page 1 */
     u32 change_counter;           /* Initial value of change-counter field */
@@ -38682,6 +40159,30 @@
 }
 
 /*
+** This function may only be called while a write-transaction is active in
+** rollback. If the connection is in WAL mode, this call is a no-op. 
+** Otherwise, if the connection does not already have an EXCLUSIVE lock on 
+** the database file, an attempt is made to obtain one.
+**
+** If the EXCLUSIVE lock is already held or the attempt to obtain it is
+** successful, or the connection is in WAL mode, SQLITE_OK is returned.
+** Otherwise, either SQLITE_BUSY or an SQLITE_IOERR_XXX error code is 
+** returned.
+*/
+SQLITE_PRIVATE int sqlite3PagerExclusiveLock(Pager *pPager){
+  int rc = SQLITE_OK;
+  assert( pPager->eState==PAGER_WRITER_CACHEMOD 
+       || pPager->eState==PAGER_WRITER_DBMOD 
+       || pPager->eState==PAGER_WRITER_LOCKED 
+  );
+  assert( assert_pager_state(pPager) );
+  if( 0==pagerUseWal(pPager) ){
+    rc = pager_wait_on_lock(pPager, EXCLUSIVE_LOCK);
+  }
+  return rc;
+}
+
+/*
 ** Sync the database file for the pager pPager. zMaster points to the name
 ** of a master journal file that should be written into the individual
 ** journal file. zMaster may be NULL, which is interpreted as no master
@@ -38714,22 +40215,29 @@
 ){
   int rc = SQLITE_OK;             /* Return code */
 
-  /* The dbOrigSize is never set if journal_mode=OFF */
-  assert( pPager->journalMode!=PAGER_JOURNALMODE_OFF || pPager->dbOrigSize==0 );
+  assert( pPager->eState==PAGER_WRITER_LOCKED
+       || pPager->eState==PAGER_WRITER_CACHEMOD
+       || pPager->eState==PAGER_WRITER_DBMOD
+       || pPager->eState==PAGER_ERROR
+  );
+  assert( assert_pager_state(pPager) );
 
   /* If a prior error occurred, report that error again. */
-  if( pPager->errCode ) return pPager->errCode;
+  if( NEVER(pPager->errCode) ) return pPager->errCode;
 
   PAGERTRACE(("DATABASE SYNC: File=%s zMaster=%s nSize=%d\n", 
       pPager->zFilename, zMaster, pPager->dbSize));
 
-  if( MEMDB && pPager->dbModified ){
+  /* If no database changes have been made, return early. */
+  if( pPager->eState<PAGER_WRITER_CACHEMOD ) return SQLITE_OK;
+
+  if( MEMDB ){
     /* If this is an in-memory db, or no pages have been written to, or this
     ** function has already been called, it is mostly a no-op.  However, any
     ** backup in progress needs to be restarted.
     */
     sqlite3BackupRestart(pPager->pBackup);
-  }else if( pPager->state!=PAGER_SYNCED && pPager->dbModified ){
+  }else{
     if( pagerUseWal(pPager) ){
       PgHdr *pList = sqlite3PcacheDirtyList(pPager->pPCache);
       if( pList ){
@@ -38772,7 +40280,7 @@
       );
       if( !zMaster && isOpen(pPager->jfd) 
        && pPager->journalOff==jrnlBufferSize(pPager) 
-       && pPager->dbSize>=pPager->dbFileSize
+       && pPager->dbSize>=pPager->dbOrigSize
        && (0==(pPg = sqlite3PcacheDirtyList(pPager->pPCache)) || 0==pPg->pDirty)
       ){
         /* Update the db file change counter via the direct-write method. The 
@@ -38802,13 +40310,10 @@
       ** that it took at the start of the transaction. Otherwise, the
       ** calls to sqlite3PagerGet() return zeroed pages instead of 
       ** reading data from the database file.
-      **
-      ** When journal_mode==OFF the dbOrigSize is always zero, so this
-      ** block never runs if journal_mode=OFF.
       */
   #ifndef SQLITE_OMIT_AUTOVACUUM
       if( pPager->dbSize<pPager->dbOrigSize 
-       && ALWAYS(pPager->journalMode!=PAGER_JOURNALMODE_OFF)
+       && pPager->journalMode!=PAGER_JOURNALMODE_OFF
       ){
         Pgno i;                                   /* Iterator variable */
         const Pgno iSkip = PAGER_MJ_PGNO(pPager); /* Pending lock page */
@@ -38835,14 +40340,20 @@
       rc = writeMasterJournal(pPager, zMaster);
       if( rc!=SQLITE_OK ) goto commit_phase_one_exit;
   
-      /* Sync the journal file. If the atomic-update optimization is being
-      ** used, this call will not create the journal file or perform any
-      ** real IO.
+      /* Sync the journal file and write all dirty pages to the database.
+      ** If the atomic-update optimization is being used, this sync will not 
+      ** create the journal file or perform any real IO.
+      **
+      ** Because the change-counter page was just modified, unless the
+      ** atomic-update optimization is used it is almost certain that the
+      ** journal requires a sync here. However, in locking_mode=exclusive
+      ** on a system under memory pressure it is just possible that this is 
+      ** not the case. In this case it is likely enough that the redundant
+      ** xSync() call will be changed to a no-op by the OS anyhow. 
       */
-      rc = syncJournal(pPager);
+      rc = syncJournal(pPager, 0);
       if( rc!=SQLITE_OK ) goto commit_phase_one_exit;
   
-      /* Write all dirty pages to the database file. */
       rc = pager_write_pagelist(pPager,sqlite3PcacheDirtyList(pPager->pPCache));
       if( rc!=SQLITE_OK ){
         assert( rc!=SQLITE_IOERR_BLOCKED );
@@ -38855,7 +40366,7 @@
       */
       if( pPager->dbSize!=pPager->dbFileSize ){
         Pgno nNew = pPager->dbSize - (pPager->dbSize==PAGER_MJ_PGNO(pPager));
-        assert( pPager->state>=PAGER_EXCLUSIVE );
+        assert( pPager->eState==PAGER_WRITER_DBMOD );
         rc = pager_truncate(pPager, nNew);
         if( rc!=SQLITE_OK ) goto commit_phase_one_exit;
       }
@@ -38866,11 +40377,12 @@
       }
       IOTRACE(("DBSYNC %p\n", pPager))
     }
-
-    pPager->state = PAGER_SYNCED;
   }
 
 commit_phase_one_exit:
+  if( rc==SQLITE_OK && !pagerUseWal(pPager) ){
+    pPager->eState = PAGER_WRITER_FINISHED;
+  }
   return rc;
 }
 
@@ -38898,12 +40410,11 @@
   ** called, just return the same error code without doing anything. */
   if( NEVER(pPager->errCode) ) return pPager->errCode;
 
-  /* This function should not be called if the pager is not in at least
-  ** PAGER_RESERVED state. **FIXME**: Make it so that this test always
-  ** fails - make it so that we never reach this point if we do not hold
-  ** all necessary locks.
-  */
-  if( NEVER(pPager->state<PAGER_RESERVED) ) return SQLITE_ERROR;
+  assert( pPager->eState==PAGER_WRITER_LOCKED
+       || pPager->eState==PAGER_WRITER_FINISHED
+       || (pagerUseWal(pPager) && pPager->eState==PAGER_WRITER_CACHEMOD)
+  );
+  assert( assert_pager_state(pPager) );
 
   /* An optimization. If the database was not actually modified during
   ** this transaction, the pager is running in exclusive-mode and is
@@ -38916,102 +40427,76 @@
   ** header. Since the pager is in exclusive mode, there is no need
   ** to drop any locks either.
   */
-  if( pPager->dbModified==0 && pPager->exclusiveMode 
+  if( pPager->eState==PAGER_WRITER_LOCKED 
+   && pPager->exclusiveMode 
    && pPager->journalMode==PAGER_JOURNALMODE_PERSIST
   ){
     assert( pPager->journalOff==JOURNAL_HDR_SZ(pPager) || !pPager->journalOff );
+    pPager->eState = PAGER_READER;
     return SQLITE_OK;
   }
 
   PAGERTRACE(("COMMIT %d\n", PAGERID(pPager)));
-  assert( pPager->state==PAGER_SYNCED || MEMDB || !pPager->dbModified );
   rc = pager_end_transaction(pPager, pPager->setMaster);
   return pager_error(pPager, rc);
 }
 
 /*
-** Rollback all changes. The database falls back to PAGER_SHARED mode.
+** If a write transaction is open, then all changes made within the 
+** transaction are reverted and the current write-transaction is closed.
+** The pager falls back to PAGER_READER state if successful, or PAGER_ERROR
+** state if an error occurs.
 **
-** This function performs two tasks:
+** If the pager is already in PAGER_ERROR state when this function is called,
+** it returns Pager.errCode immediately. No work is performed in this case.
+**
+** Otherwise, in rollback mode, this function performs two functions:
 **
 **   1) It rolls back the journal file, restoring all database file and 
 **      in-memory cache pages to the state they were in when the transaction
 **      was opened, and
+**
 **   2) It finalizes the journal file, so that it is not used for hot
 **      rollback at any point in the future.
 **
-** subject to the following qualifications:
+** Finalization of the journal file (task 2) is only performed if the 
+** rollback is successful.
 **
-** * If the journal file is not yet open when this function is called,
-**   then only (2) is performed. In this case there is no journal file
-**   to roll back.
-**
-** * If in an error state other than SQLITE_FULL, then task (1) is 
-**   performed. If successful, task (2). Regardless of the outcome
-**   of either, the error state error code is returned to the caller
-**   (i.e. either SQLITE_IOERR or SQLITE_CORRUPT).
-**
-** * If the pager is in PAGER_RESERVED state, then attempt (1). Whether
-**   or not (1) is successful, also attempt (2). If successful, return
-**   SQLITE_OK. Otherwise, enter the error state and return the first 
-**   error code encountered. 
-**
-**   In this case there is no chance that the database was written to. 
-**   So is safe to finalize the journal file even if the playback 
-**   (operation 1) failed. However the pager must enter the error state
-**   as the contents of the in-memory cache are now suspect.
-**
-** * Finally, if in PAGER_EXCLUSIVE state, then attempt (1). Only
-**   attempt (2) if (1) is successful. Return SQLITE_OK if successful,
-**   otherwise enter the error state and return the error code from the 
-**   failing operation.
-**
-**   In this case the database file may have been written to. So if the
-**   playback operation did not succeed it would not be safe to finalize
-**   the journal file. It needs to be left in the file-system so that
-**   some other process can use it to restore the database state (by
-**   hot-journal rollback).
+** In WAL mode, all cache-entries containing data modified within the
+** current transaction are either expelled from the cache or reverted to
+** their pre-transaction state by re-reading data from the database or
+** WAL files. The WAL transaction is then closed.
 */
 SQLITE_PRIVATE int sqlite3PagerRollback(Pager *pPager){
   int rc = SQLITE_OK;                  /* Return code */
   PAGERTRACE(("ROLLBACK %d\n", PAGERID(pPager)));
+
+  /* PagerRollback() is a no-op if called in READER or OPEN state. If
+  ** the pager is already in the ERROR state, the rollback is not 
+  ** attempted here. Instead, the error code is returned to the caller.
+  */
+  assert( assert_pager_state(pPager) );
+  if( pPager->eState==PAGER_ERROR ) return pPager->errCode;
+  if( pPager->eState<=PAGER_READER ) return SQLITE_OK;
+
   if( pagerUseWal(pPager) ){
     int rc2;
-
     rc = sqlite3PagerSavepoint(pPager, SAVEPOINT_ROLLBACK, -1);
     rc2 = pager_end_transaction(pPager, pPager->setMaster);
     if( rc==SQLITE_OK ) rc = rc2;
-    rc = pager_error(pPager, rc);
-  }else if( !pPager->dbModified || !isOpen(pPager->jfd) ){
-    rc = pager_end_transaction(pPager, pPager->setMaster);
-  }else if( pPager->errCode && pPager->errCode!=SQLITE_FULL ){
-    if( pPager->state>=PAGER_EXCLUSIVE ){
-      pager_playback(pPager, 0);
-    }
-    rc = pPager->errCode;
+  }else if( !isOpen(pPager->jfd) || pPager->eState==PAGER_WRITER_LOCKED ){
+    rc = pager_end_transaction(pPager, 0);
   }else{
-    if( pPager->state==PAGER_RESERVED ){
-      int rc2;
-      rc = pager_playback(pPager, 0);
-      rc2 = pager_end_transaction(pPager, pPager->setMaster);
-      if( rc==SQLITE_OK ){
-        rc = rc2;
-      }
-    }else{
-      rc = pager_playback(pPager, 0);
-    }
-
-    if( !MEMDB ){
-      pPager->dbSizeValid = 0;
-    }
-
-    /* If an error occurs during a ROLLBACK, we can no longer trust the pager
-    ** cache. So call pager_error() on the way out to make any error 
-    ** persistent.
-    */
-    rc = pager_error(pPager, rc);
+    rc = pager_playback(pPager, 0);
   }
-  return rc;
+
+  assert( pPager->eState==PAGER_READER || rc!=SQLITE_OK );
+  assert( rc==SQLITE_OK || rc==SQLITE_FULL || (rc&0xFF)==SQLITE_IOERR );
+
+  /* If an error occurs during a ROLLBACK, we can no longer trust the pager
+  ** cache. So call pager_error() on the way out to make any error persistent.
+  */
+  return pager_error(pPager, rc);
 }
 
 /*
@@ -39034,9 +40519,11 @@
 ** used by the pager and its associated cache.
 */
 SQLITE_PRIVATE int sqlite3PagerMemUsed(Pager *pPager){
-  int perPageSize = pPager->pageSize + pPager->nExtra + 20;
+  int perPageSize = pPager->pageSize + pPager->nExtra + sizeof(PgHdr)
+                                     + 5*sizeof(void*);
   return perPageSize*sqlite3PcachePagecount(pPager->pPCache)
-           + sqlite3MallocSize(pPager);
+           + sqlite3MallocSize(pPager)
+           + pPager->pageSize;
 }
 
 /*
@@ -39055,8 +40542,8 @@
   a[0] = sqlite3PcacheRefCount(pPager->pPCache);
   a[1] = sqlite3PcachePagecount(pPager->pPCache);
   a[2] = sqlite3PcacheGetCachesize(pPager->pPCache);
-  a[3] = pPager->dbSizeValid ? (int) pPager->dbSize : -1;
-  a[4] = pPager->state;
+  a[3] = pPager->eState==PAGER_OPEN ? -1 : (int) pPager->dbSize;
+  a[4] = pPager->eState;
   a[5] = pPager->errCode;
   a[6] = pPager->nHit;
   a[7] = pPager->nMiss;
@@ -39088,13 +40575,12 @@
   int rc = SQLITE_OK;                       /* Return code */
   int nCurrent = pPager->nSavepoint;        /* Current number of savepoints */
 
+  assert( pPager->eState>=PAGER_WRITER_LOCKED );
+  assert( assert_pager_state(pPager) );
+
   if( nSavepoint>nCurrent && pPager->useJournal ){
     int ii;                                 /* Iterator variable */
     PagerSavepoint *aNew;                   /* New Pager.aSavepoint array */
-    int nPage;                              /* Size of database file */
-
-    rc = sqlite3PagerPagecount(pPager, &nPage);
-    if( rc ) return rc;
 
     /* Grow the Pager.aSavepoint array using realloc(). Return SQLITE_NOMEM
     ** if the allocation fails. Otherwise, zero the new portion in case a 
@@ -39111,14 +40597,14 @@
 
     /* Populate the PagerSavepoint structures just allocated. */
     for(ii=nCurrent; ii<nSavepoint; ii++){
-      aNew[ii].nOrig = nPage;
+      aNew[ii].nOrig = pPager->dbSize;
       if( isOpen(pPager->jfd) && pPager->journalOff>0 ){
         aNew[ii].iOffset = pPager->journalOff;
       }else{
         aNew[ii].iOffset = JOURNAL_HDR_SZ(pPager);
       }
       aNew[ii].iSubRec = pPager->nSubRec;
-      aNew[ii].pInSavepoint = sqlite3BitvecCreate(nPage);
+      aNew[ii].pInSavepoint = sqlite3BitvecCreate(pPager->dbSize);
       if( !aNew[ii].pInSavepoint ){
         return SQLITE_NOMEM;
       }
@@ -39165,12 +40651,12 @@
 ** savepoint. If no errors occur, SQLITE_OK is returned.
 */ 
 SQLITE_PRIVATE int sqlite3PagerSavepoint(Pager *pPager, int op, int iSavepoint){
-  int rc = SQLITE_OK;
+  int rc = pPager->errCode;       /* Return code */
 
   assert( op==SAVEPOINT_RELEASE || op==SAVEPOINT_ROLLBACK );
   assert( iSavepoint>=0 || op==SAVEPOINT_ROLLBACK );
 
-  if( iSavepoint<pPager->nSavepoint ){
+  if( rc==SQLITE_OK && iSavepoint<pPager->nSavepoint ){
     int ii;            /* Iterator variable */
     int nNew;          /* Number of remaining savepoints after this op. */
 
@@ -39206,8 +40692,8 @@
       rc = pagerPlaybackSavepoint(pPager, pSavepoint);
       assert(rc!=SQLITE_DONE);
     }
-  
   }
+
   return rc;
 }
 
@@ -39305,6 +40791,10 @@
   Pgno origPgno;               /* The original page number */
 
   assert( pPg->nRef>0 );
+  assert( pPager->eState==PAGER_WRITER_CACHEMOD
+       || pPager->eState==PAGER_WRITER_DBMOD
+  );
+  assert( assert_pager_state(pPager) );
 
   /* In order to be able to rollback, an in-memory database must journal
   ** the page we are moving from.
@@ -39354,11 +40844,10 @@
     needSyncPgno = pPg->pgno;
     assert( pageInJournal(pPg) || pPg->pgno>pPager->dbOrigSize );
     assert( pPg->flags&PGHDR_DIRTY );
-    assert( pPager->needSync );
   }
 
   /* If the cache contains a page with page-number pgno, remove it
-  ** from its hash chain. Also, if the PgHdr.needSync was set for 
+  ** from its hash chain. Also, if the PGHDR_NEED_SYNC flag was set for 
   ** page pgno before the 'move' operation, it needs to be retained 
   ** for the page moved there.
   */
@@ -39370,7 +40859,6 @@
     if( MEMDB ){
       /* Do not discard pages from an in-memory database since we might
       ** need to rollback later.  Just move the page out of the way. */
-      assert( pPager->dbSizeValid );
       sqlite3PcacheMove(pPgOld, pPager->dbSize+1);
     }else{
       sqlite3PcacheDrop(pPgOld);
@@ -39380,14 +40868,23 @@
   origPgno = pPg->pgno;
   sqlite3PcacheMove(pPg, pgno);
   sqlite3PcacheMakeDirty(pPg);
-  pPager->dbModified = 1;
+
+  /* For an in-memory database, make sure the original page continues
+  ** to exist, in case the transaction needs to roll back.  Use pPgOld
+  ** as the original page since it has already been allocated.
+  */
+  if( MEMDB ){
+    assert( pPgOld );
+    sqlite3PcacheMove(pPgOld, origPgno);
+    sqlite3PagerUnref(pPgOld);
+  }
 
   if( needSyncPgno ){
     /* If needSyncPgno is non-zero, then the journal file needs to be 
     ** sync()ed before any data is written to database file page needSyncPgno.
     ** Currently, no such page exists in the page-cache and the 
     ** "is journaled" bitvec flag has been set. This needs to be remedied by
-    ** loading the page into the pager-cache and setting the PgHdr.needSync 
+    ** loading the page into the pager-cache and setting the PGHDR_NEED_SYNC
     ** flag.
     **
     ** If the attempt to load the page into the page-cache fails, (due
@@ -39396,12 +40893,8 @@
     ** this transaction, it may be written to the database file before
     ** it is synced into the journal file. This way, it may end up in
     ** the journal file twice, but that is not a problem.
-    **
-    ** The sqlite3PagerGet() call may cause the journal to sync. So make
-    ** sure the Pager.needSync flag is set too.
     */
     PgHdr *pPgHdr;
-    assert( pPager->needSync );
     rc = sqlite3PagerGet(pPager, needSyncPgno, &pPgHdr);
     if( rc!=SQLITE_OK ){
       if( needSyncPgno<=pPager->dbOrigSize ){
@@ -39410,23 +40903,11 @@
       }
       return rc;
     }
-    pPager->needSync = 1;
-    assert( pPager->noSync==0 && !MEMDB );
     pPgHdr->flags |= PGHDR_NEED_SYNC;
     sqlite3PcacheMakeDirty(pPgHdr);
     sqlite3PagerUnref(pPgHdr);
   }
 
-  /*
-  ** For an in-memory database, make sure the original page continues
-  ** to exist, in case the transaction needs to roll back.  Use pPgOld
-  ** as the original page since it has already been allocated.
-  */
-  if( MEMDB ){
-    sqlite3PcacheMove(pPgOld, origPgno);
-    sqlite3PagerUnref(pPgOld);
-  }
-
   return SQLITE_OK;
 }
 #endif
@@ -39492,6 +40973,13 @@
 SQLITE_PRIVATE int sqlite3PagerSetJournalMode(Pager *pPager, int eMode){
   u8 eOld = pPager->journalMode;    /* Prior journalmode */
 
+#ifdef SQLITE_DEBUG
+  /* The print_pager_state() routine is intended to be used by the debugger
+  ** only.  We invoke it once here to suppress a compiler warning. */
+  print_pager_state(pPager);
+#endif
+
+
   /* The eMode parameter is always valid */
   assert(      eMode==PAGER_JOURNALMODE_DELETE
             || eMode==PAGER_JOURNALMODE_TRUNCATE
@@ -39500,12 +40988,11 @@
             || eMode==PAGER_JOURNALMODE_WAL 
             || eMode==PAGER_JOURNALMODE_MEMORY );
 
-  /* Do not allow the journalmode of a TEMP database to be changed to WAL
+  /* This routine is only called from the OP_JournalMode opcode, and
+  ** the logic there will never allow a temporary file to be changed
+  ** to WAL mode.
   */
-  if( pPager->tempFile && eMode==PAGER_JOURNALMODE_WAL ){
-    assert( eOld!=PAGER_JOURNALMODE_WAL );
-    eMode = eOld;
-  }
+  assert( pPager->tempFile==0 || eMode!=PAGER_JOURNALMODE_WAL );
 
   /* Do allow the journalmode of an in-memory database to be set to
   ** anything other than MEMORY or OFF
@@ -39518,20 +41005,13 @@
   }
 
   if( eMode!=eOld ){
-    /* When changing between rollback modes, close the journal file prior
-    ** to the change.  But when changing from a rollback mode to WAL, keep
-    ** the journal open since there is a rollback-style transaction in play
-    ** used to convert the version numbers in the btree header.
-    */
-    if( isOpen(pPager->jfd) && eMode!=PAGER_JOURNALMODE_WAL ){
-      sqlite3OsClose(pPager->jfd);
-    }
 
     /* Change the journal mode. */
+    assert( pPager->eState!=PAGER_ERROR );
     pPager->journalMode = (u8)eMode;
 
     /* When transistioning from TRUNCATE or PERSIST to any other journal
-    ** mode except WAL (and we are not in locking_mode=EXCLUSIVE) then 
+    ** mode except WAL, unless the pager is in locking_mode=exclusive mode,
     ** delete the journal file.
     */
     assert( (PAGER_JOURNALMODE_TRUNCATE & 5)==1 );
@@ -39552,24 +41032,30 @@
       ** database file. This ensures that the journal file is not deleted
       ** while it is in use by some other client.
       */
-      int rc = SQLITE_OK;
-      int state = pPager->state;
-      if( state<PAGER_SHARED ){
-        rc = sqlite3PagerSharedLock(pPager);
-      }
-      if( pPager->state==PAGER_SHARED ){
-        assert( rc==SQLITE_OK );
-        rc = sqlite3OsLock(pPager->fd, RESERVED_LOCK);
-      }
-      if( rc==SQLITE_OK ){
+      sqlite3OsClose(pPager->jfd);
+      if( pPager->eLock>=RESERVED_LOCK ){
         sqlite3OsDelete(pPager->pVfs, pPager->zJournal, 0);
+      }else{
+        int rc = SQLITE_OK;
+        int state = pPager->eState;
+        assert( state==PAGER_OPEN || state==PAGER_READER );
+        if( state==PAGER_OPEN ){
+          rc = sqlite3PagerSharedLock(pPager);
+        }
+        if( pPager->eState==PAGER_READER ){
+          assert( rc==SQLITE_OK );
+          rc = pagerLockDb(pPager, RESERVED_LOCK);
+        }
+        if( rc==SQLITE_OK ){
+          sqlite3OsDelete(pPager->pVfs, pPager->zJournal, 0);
+        }
+        if( rc==SQLITE_OK && state==PAGER_READER ){
+          pagerUnlockDb(pPager, SHARED_LOCK);
+        }else if( state==PAGER_OPEN ){
+          pager_unlock(pPager);
+        }
+        assert( state==pPager->eState );
       }
-      if( rc==SQLITE_OK && state==PAGER_SHARED ){
-        sqlite3OsUnlock(pPager->fd, SHARED_LOCK);
-      }else if( state==PAGER_UNLOCK ){
-        pager_unlock(pPager);
-      }
-      assert( state==pPager->state );
     }
   }
 
@@ -39590,7 +41076,8 @@
 ** is unmodified.
 */
 SQLITE_PRIVATE int sqlite3PagerOkToChangeJournalMode(Pager *pPager){
-  if( pPager->dbModified ) return 0;
+  assert( assert_pager_state(pPager) );
+  if( pPager->eState>=PAGER_WRITER_CACHEMOD ) return 0;
   if( NEVER(isOpen(pPager->jfd) && pPager->journalOff>0) ) return 0;
   return 1;
 }
@@ -39644,7 +41131,7 @@
 */
 SQLITE_PRIVATE int sqlite3PagerWalSupported(Pager *pPager){
   const sqlite3_io_methods *pMethods = pPager->fd->pMethods;
-  return pMethods->iVersion>=2 && pMethods->xShmOpen!=0;
+  return pMethods->iVersion>=2 && pMethods->xShmMap!=0;
 }
 
 /*
@@ -39655,25 +41142,31 @@
 ** file (not a temp file or an in-memory database), and the WAL file
 ** is not already open, make an attempt to open it now. If successful,
 ** return SQLITE_OK. If an error occurs or the VFS used by the pager does 
-** not support the xShmXXX() methods, return an error code. *pisOpen is
+** not support the xShmXXX() methods, return an error code. *pbOpen is
 ** not modified in either case.
 **
 ** If the pager is open on a temp-file (or in-memory database), or if
-** the WAL file is already open, set *pisOpen to 1 and return SQLITE_OK
+** the WAL file is already open, set *pbOpen to 1 and return SQLITE_OK
 ** without doing anything.
 */
 SQLITE_PRIVATE int sqlite3PagerOpenWal(
   Pager *pPager,                  /* Pager object */
-  int *pisOpen                    /* OUT: Set to true if call is a no-op */
+  int *pbOpen                     /* OUT: Set to true if call is a no-op */
 ){
   int rc = SQLITE_OK;             /* Return code */
 
-  assert( pPager->state>=PAGER_SHARED );
-  assert( (pisOpen==0 && !pPager->tempFile && !pPager->pWal) || *pisOpen==0 );
+  assert( assert_pager_state(pPager) );
+  assert( pPager->eState==PAGER_OPEN   || pbOpen );
+  assert( pPager->eState==PAGER_READER || !pbOpen );
+  assert( pbOpen==0 || *pbOpen==0 );
+  assert( pbOpen!=0 || (!pPager->tempFile && !pPager->pWal) );
 
   if( !pPager->tempFile && !pPager->pWal ){
     if( !sqlite3PagerWalSupported(pPager) ) return SQLITE_CANTOPEN;
 
+    /* Close any rollback journal previously open */
+    sqlite3OsClose(pPager->jfd);
+
     /* Open the connection to the log file. If this operation fails, 
     ** (e.g. due to malloc() failure), unlock the database file and 
     ** return an error code.
@@ -39681,9 +41174,10 @@
     rc = sqlite3WalOpen(pPager->pVfs, pPager->fd, pPager->zWal, &pPager->pWal);
     if( rc==SQLITE_OK ){
       pPager->journalMode = PAGER_JOURNALMODE_WAL;
+      pPager->eState = PAGER_OPEN;
     }
   }else{
-    *pisOpen = 1;
+    *pbOpen = 1;
   }
 
   return rc;
@@ -39709,7 +41203,7 @@
   */
   if( !pPager->pWal ){
     int logexists = 0;
-    rc = sqlite3OsLock(pPager->fd, SQLITE_LOCK_SHARED);
+    rc = pagerLockDb(pPager, SHARED_LOCK);
     if( rc==SQLITE_OK ){
       rc = sqlite3OsAccess(
           pPager->pVfs, pPager->zWal, SQLITE_ACCESS_EXISTS, &logexists
@@ -39725,7 +41219,7 @@
   ** the database file, the log and log-summary files will be deleted.
   */
   if( rc==SQLITE_OK && pPager->pWal ){
-    rc = sqlite3OsLock(pPager->fd, SQLITE_LOCK_EXCLUSIVE);
+    rc = pagerLockDb(pPager, EXCLUSIVE_LOCK);
     if( rc==SQLITE_OK ){
       rc = sqlite3WalClose(pPager->pWal,
                            (pPager->noSync ? 0 : pPager->sync_flags), 
@@ -39735,7 +41229,7 @@
     }else{
       /* If we cannot get an EXCLUSIVE lock, downgrade the PENDING lock
       ** that we did get back to SHARED. */
-      sqlite3OsUnlock(pPager->fd, SQLITE_LOCK_SHARED);
+      pagerUnlockDb(pPager, SQLITE_LOCK_SHARED);
     }
   }
   return rc;
@@ -40055,6 +41549,10 @@
 **
 ** The actual header in the wal-index consists of two copies of this
 ** object.
+**
+** The szPage value can be any power of 2 between 512 and 32768, inclusive.
+** Or it can be 1 to represent a 65536-byte page.  The latter case was
+** added in 3.7.1 when support for 64K pages was added.  
 */
 struct WalIndexHdr {
   u32 iVersion;                   /* Wal-index version */
@@ -40062,7 +41560,7 @@
   u32 iChange;                    /* Counter incremented each transaction */
   u8 isInit;                      /* 1 when initialized */
   u8 bigEndCksum;                 /* True if checksums in WAL are big-endian */
-  u16 szPage;                     /* Database page size in bytes */
+  u16 szPage;                     /* Database page size in bytes. 1==64K */
   u32 mxFrame;                    /* Index of last valid frame in the WAL */
   u32 nPage;                      /* Size of database in pages */
   u32 aFrameCksum[2];             /* Checksum of last frame in log */
@@ -40173,12 +41671,12 @@
   u32 iCallback;             /* Value to pass to log callback (or 0) */
   int nWiData;               /* Size of array apWiData */
   volatile u32 **apWiData;   /* Pointer to wal-index content in memory */
-  u16 szPage;                /* Database page size */
+  u32 szPage;                /* Database page size */
   i16 readLock;              /* Which read lock is being held.  -1 for none */
   u8 exclusiveMode;          /* Non-zero if connection is in exclusive mode */
-  u8 isWIndexOpen;           /* True if ShmOpen() called on pDbFd */
   u8 writeLock;              /* True if in a write transaction */
   u8 ckptLock;               /* True if holding a checkpoint lock */
+  u8 readOnly;               /* True if the WAL file is open read-only */
   WalIndexHdr hdr;           /* Wal-index header for current transaction */
   const char *zWalName;      /* Name of WAL file */
   u32 nCkpt;                 /* Checkpoint sequence counter in the wal-header */
@@ -40258,14 +41756,15 @@
 
   /* Enlarge the pWal->apWiData[] array if required */
   if( pWal->nWiData<=iPage ){
-    int nByte = sizeof(u32 *)*(iPage+1);
+    int nByte = sizeof(u32*)*(iPage+1);
     volatile u32 **apNew;
     apNew = (volatile u32 **)sqlite3_realloc((void *)pWal->apWiData, nByte);
     if( !apNew ){
       *ppPage = 0;
       return SQLITE_NOMEM;
     }
-    memset((void *)&apNew[pWal->nWiData], 0, sizeof(u32 *)*(iPage+1-pWal->nWiData));
+    memset((void*)&apNew[pWal->nWiData], 0,
+           sizeof(u32*)*(iPage+1-pWal->nWiData));
     pWal->apWiData = apNew;
     pWal->nWiData = iPage+1;
   }
@@ -40441,9 +41940,10 @@
     return 0;
   }
 
-  /* A frame is only valid if a checksum of the first 16 bytes
-  ** of the frame-header, and the frame-data matches
-  ** the checksum in the last 8 bytes of the frame-header.
+  /* A frame is only valid if a checksum of the WAL header,
+  ** all prior frams, the first 16 bytes of this frame-header, 
+  ** and the frame-data matches the checksum in the last 8 
+  ** bytes of this frame-header.
   */
   nativeCksum = (pWal->hdr.bigEndCksum==SQLITE_BIGENDIAN);
   walChecksumBytes(nativeCksum, aFrame, 8, aCksum, aCksum);
@@ -40703,7 +42203,7 @@
   if( rc==SQLITE_OK ){
     int iKey;                     /* Hash table key */
     int idx;                      /* Value to write to hash-table slot */
-    TESTONLY( int nCollide = 0;   /* Number of hash collisions */ )
+    int nCollide;                 /* Number of hash collisions */
 
     idx = iFrame - iZero;
     assert( idx <= HASHTABLE_NSLOT/2 + 1 );
@@ -40728,8 +42228,9 @@
     }
 
     /* Write the aPgno[] array entry and the hash-table slot. */
+    nCollide = idx;
     for(iKey=walHash(iPage); aHash[iKey]; iKey=walNextHash(iKey)){
-      assert( nCollide++ < idx );
+      if( (nCollide--)==0 ) return SQLITE_CORRUPT_BKPT;
     }
     aPgno[idx] = iPage;
     aHash[iKey] = (ht_slot)idx;
@@ -40841,7 +42342,7 @@
       goto finished;
     }
     pWal->hdr.bigEndCksum = (u8)(magic&0x00000001);
-    pWal->szPage = (u16)szPage;
+    pWal->szPage = szPage;
     pWal->nCkpt = sqlite3Get4byte(&aBuf[12]);
     memcpy(&pWal->hdr.aSalt, &aBuf[16], 8);
 
@@ -40891,7 +42392,9 @@
       if( nTruncate ){
         pWal->hdr.mxFrame = iFrame;
         pWal->hdr.nPage = nTruncate;
-        pWal->hdr.szPage = (u16)szPage;
+        pWal->hdr.szPage = (u16)((szPage&0xff00) | (szPage>>16));
+        testcase( szPage<=32768 );
+        testcase( szPage>=65536 );
         aFrameCksum[0] = pWal->hdr.aFrameCksum[0];
         aFrameCksum[1] = pWal->hdr.aFrameCksum[1];
       }
@@ -40916,6 +42419,17 @@
     pInfo->nBackfill = 0;
     pInfo->aReadMark[0] = 0;
     for(i=1; i<WAL_NREADER; i++) pInfo->aReadMark[i] = READMARK_NOT_USED;
+
+    /* If more than one frame was recovered from the log file, report an
+    ** event via sqlite3_log(). This is to help with identifying performance
+    ** problems caused by applications routinely shutting down without
+    ** checkpointing the log file.
+    */
+    if( pWal->hdr.nPage ){
+      sqlite3_log(SQLITE_OK, "Recovered %d frames from WAL file %s",
+          pWal->hdr.nPage, pWal->zWalName
+      );
+    }
   }
 
 recovery_error:
@@ -40928,10 +42442,7 @@
 ** Close an open wal-index.
 */
 static void walIndexClose(Wal *pWal, int isDelete){
-  if( pWal->isWIndexOpen ){
-    sqlite3OsShmClose(pWal->pDbFd, isDelete);
-    pWal->isWIndexOpen = 0;
-  }
+  sqlite3OsShmUnmap(pWal->pDbFd, isDelete);
 }
 
 /* 
@@ -40985,15 +42496,13 @@
   pRet->pWalFd = (sqlite3_file *)&pRet[1];
   pRet->pDbFd = pDbFd;
   pRet->readLock = -1;
-  sqlite3_randomness(8, &pRet->hdr.aSalt);
   pRet->zWalName = zWalName;
-  rc = sqlite3OsShmOpen(pDbFd);
 
   /* Open file handle on the write-ahead log file. */
-  if( rc==SQLITE_OK ){
-    pRet->isWIndexOpen = 1;
-    flags = (SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE|SQLITE_OPEN_MAIN_JOURNAL);
-    rc = sqlite3OsOpen(pVfs, zWalName, pRet->pWalFd, flags, &flags);
+  flags = (SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE|SQLITE_OPEN_WAL);
+  rc = sqlite3OsOpen(pVfs, zWalName, pRet->pWalFd, flags, &flags);
+  if( rc==SQLITE_OK && flags&SQLITE_OPEN_READONLY ){
+    pRet->readOnly = 1;
   }
 
   if( rc!=SQLITE_OK ){
@@ -41216,7 +42725,11 @@
       ht_slot *aIndex;            /* Sorted index for this segment */
 
       aPgno++;
-      nEntry = (int)(((i+1)==nSegment)?(int)(iLast-iZero):(u32 *)aHash-(u32 *)aPgno);
+      if( (i+1)==nSegment ){
+        nEntry = (int)(iLast - iZero);
+      }else{
+        nEntry = (int)((u32*)aHash - (u32*)aPgno);
+      }
       aIndex = &((ht_slot *)&p->aSegment[p->nSegment])[iZero];
       iZero++;
   
@@ -41277,14 +42790,18 @@
   u8 *zBuf                        /* Temporary buffer to use */
 ){
   int rc;                         /* Return code */
-  int szPage = pWal->hdr.szPage;  /* Database page-size */
+  int szPage;                     /* Database page-size */
   WalIterator *pIter = 0;         /* Wal iterator context */
   u32 iDbpage = 0;                /* Next database page to write */
   u32 iFrame = 0;                 /* Wal frame containing data for iDbpage */
   u32 mxSafeFrame;                /* Max frame that can be backfilled */
+  u32 mxPage;                     /* Max database page to write */
   int i;                          /* Loop counter */
   volatile WalCkptInfo *pInfo;    /* The checkpoint status information */
 
+  szPage = (pWal->hdr.szPage&0xfe00) + ((pWal->hdr.szPage&0x0001)<<16);
+  testcase( szPage<=32768 );
+  testcase( szPage>=65536 );
   if( pWal->hdr.mxFrame==0 ) return SQLITE_OK;
 
   /* Allocate the iterator */
@@ -41295,7 +42812,7 @@
   assert( pIter );
 
   /*** TODO:  Move this test out to the caller.  Make it an assert() here ***/
-  if( pWal->hdr.szPage!=nBuf ){
+  if( szPage!=nBuf ){
     rc = SQLITE_CORRUPT_BKPT;
     goto walcheckpoint_out;
   }
@@ -41306,6 +42823,7 @@
   ** cannot be backfilled from the WAL.
   */
   mxSafeFrame = pWal->hdr.mxFrame;
+  mxPage = pWal->hdr.nPage;
   pInfo = walCkptInfo(pWal);
   for(i=1; i<WAL_NREADER; i++){
     u32 y = pInfo->aReadMark[i];
@@ -41326,6 +42844,7 @@
   if( pInfo->nBackfill<mxSafeFrame
    && (rc = walLockExclusive(pWal, WAL_READ_LOCK(0), 1))==SQLITE_OK
   ){
+    i64 nSize;                    /* Current size of database file */
     u32 nBackfill = pInfo->nBackfill;
 
     /* Sync the WAL to disk */
@@ -41333,11 +42852,22 @@
       rc = sqlite3OsSync(pWal->pWalFd, sync_flags);
     }
 
+    /* If the database file may grow as a result of this checkpoint, hint
+    ** about the eventual size of the db file to the VFS layer. 
+    */
+    if( rc==SQLITE_OK ){
+      i64 nReq = ((i64)mxPage * szPage);
+      rc = sqlite3OsFileSize(pWal->pDbFd, &nSize);
+      if( rc==SQLITE_OK && nSize<nReq ){
+        sqlite3OsFileControl(pWal->pDbFd, SQLITE_FCNTL_SIZE_HINT, &nReq);
+      }
+    }
+
     /* Iterate through the contents of the WAL, copying data to the db file. */
     while( rc==SQLITE_OK && 0==walIteratorNext(pIter, &iDbpage, &iFrame) ){
       i64 iOffset;
       assert( walFramePgno(pWal, iFrame)==iDbpage );
-      if( iFrame<=nBackfill || iFrame>mxSafeFrame ) continue;
+      if( iFrame<=nBackfill || iFrame>mxSafeFrame || iDbpage>mxPage ) continue;
       iOffset = walFrameOffset(iFrame, szPage) + WAL_FRAME_HDRSIZE;
       /* testcase( IS_BIG_INT(iOffset) ); // requires a 4GiB WAL file */
       rc = sqlite3OsRead(pWal->pWalFd, zBuf, szPage, iOffset);
@@ -41444,7 +42974,7 @@
   /* The first page of the wal-index must be mapped at this point. */
   assert( pWal->nWiData>0 && pWal->apWiData[0] );
 
-  /* Read the header. This might happen currently with a write to the
+  /* Read the header. This might happen concurrently with a write to the
   ** same area of shared memory on a different CPU in a SMP,
   ** meaning it is possible that an inconsistent snapshot is read
   ** from the file. If this happens, return non-zero.
@@ -41473,7 +43003,9 @@
   if( memcmp(&pWal->hdr, &h1, sizeof(WalIndexHdr)) ){
     *pChanged = 1;
     memcpy(&pWal->hdr, &h1, sizeof(WalIndexHdr));
-    pWal->szPage = pWal->hdr.szPage;
+    pWal->szPage = (pWal->hdr.szPage&0xfe00) + ((pWal->hdr.szPage&0x0001)<<16);
+    testcase( pWal->szPage<=32768 );
+    testcase( pWal->szPage>=65536 );
   }
 
   /* The header was successfully read. Return zero. */
@@ -41628,8 +43160,16 @@
       ** WAL_RETRY this routine will be called again and will probably be
       ** right on the second iteration.
       */
-      rc = walLockShared(pWal, WAL_RECOVER_LOCK);
-      if( rc==SQLITE_OK ){
+      if( pWal->apWiData[0]==0 ){
+        /* This branch is taken when the xShmMap() method returns SQLITE_BUSY.
+        ** We assume this is a transient condition, so return WAL_RETRY. The
+        ** xShmMap() implementation used by the default unix and win32 VFS 
+        ** modules may return SQLITE_BUSY due to a race condition in the 
+        ** code that determines whether or not the shared-memory region 
+        ** must be zeroed before the requested page is returned.
+        */
+        rc = WAL_RETRY;
+      }else if( SQLITE_OK==(rc = walLockShared(pWal, WAL_RECOVER_LOCK)) ){
         walUnlockShared(pWal, WAL_RECOVER_LOCK);
         rc = WAL_RETRY;
       }else if( rc==SQLITE_BUSY ){
@@ -41784,6 +43324,7 @@
 ** read-lock.
 */
 SQLITE_PRIVATE void sqlite3WalEndReadTransaction(Wal *pWal){
+  sqlite3WalEndWriteTransaction(pWal);
   if( pWal->readLock>=0 ){
     walUnlockShared(pWal, WAL_READ_LOCK(pWal->readLock));
     pWal->readLock = -1;
@@ -41853,18 +43394,23 @@
     volatile u32 *aPgno;          /* Pointer to array of page numbers */
     u32 iZero;                    /* Frame number corresponding to aPgno[0] */
     int iKey;                     /* Hash slot index */
-    int rc;
+    int nCollide;                 /* Number of hash collisions remaining */
+    int rc;                       /* Error code */
 
     rc = walHashGet(pWal, iHash, &aHash, &aPgno, &iZero);
     if( rc!=SQLITE_OK ){
       return rc;
     }
+    nCollide = HASHTABLE_NSLOT;
     for(iKey=walHash(pgno); aHash[iKey]; iKey=walNextHash(iKey)){
       u32 iFrame = aHash[iKey] + iZero;
       if( iFrame<=iLast && aPgno[aHash[iKey]]==pgno ){
         assert( iFrame>iRead );
         iRead = iFrame;
       }
+      if( (nCollide--)==0 ){
+        return SQLITE_CORRUPT_BKPT;
+      }
     }
   }
 
@@ -41889,7 +43435,13 @@
   ** required page. Read and return data from the log file.
   */
   if( iRead ){
-    i64 iOffset = walFrameOffset(iRead, pWal->hdr.szPage) + WAL_FRAME_HDRSIZE;
+    int sz;
+    i64 iOffset;
+    sz = pWal->hdr.szPage;
+    sz = (pWal->hdr.szPage&0xfe00) + ((pWal->hdr.szPage&0x0001)<<16);
+    testcase( sz<=32768 );
+    testcase( sz>=65536 );
+    iOffset = walFrameOffset(iRead, sz) + WAL_FRAME_HDRSIZE;
     *pInWal = 1;
     /* testcase( IS_BIG_INT(iOffset) ); // requires a 4GiB WAL */
     return sqlite3OsRead(pWal->pWalFd, pOut, nOut, iOffset);
@@ -41901,11 +43453,13 @@
 
 
 /* 
-** Set *pPgno to the size of the database file (or zero, if unknown).
+** Return the size of the database in pages (or zero, if unknown).
 */
-SQLITE_PRIVATE void sqlite3WalDbsize(Wal *pWal, Pgno *pPgno){
-  assert( pWal->readLock>=0 || pWal->lockError );
-  *pPgno = pWal->hdr.nPage;
+SQLITE_PRIVATE Pgno sqlite3WalDbsize(Wal *pWal){
+  if( pWal && ALWAYS(pWal->readLock>=0) ){
+    return pWal->hdr.nPage;
+  }
+  return 0;
 }
 
 
@@ -41929,6 +43483,10 @@
   ** transaction. */
   assert( pWal->readLock>=0 );
 
+  if( pWal->readOnly ){
+    return SQLITE_READONLY;
+  }
+
   /* Only one writer allowed at a time.  Get the write lock.  Return
   ** SQLITE_BUSY if unable.
   */
@@ -41956,8 +43514,10 @@
 ** routine merely releases the lock.
 */
 SQLITE_PRIVATE int sqlite3WalEndWriteTransaction(Wal *pWal){
-  walUnlockExclusive(pWal, WAL_WRITE_LOCK, 1);
-  pWal->writeLock = 0;
+  if( pWal->writeLock ){
+    walUnlockExclusive(pWal, WAL_WRITE_LOCK, 1);
+    pWal->writeLock = 0;
+  }
   return SQLITE_OK;
 }
 
@@ -41975,7 +43535,7 @@
 */
 SQLITE_PRIVATE int sqlite3WalUndo(Wal *pWal, int (*xUndo)(void *, Pgno), void *pUndoCtx){
   int rc = SQLITE_OK;
-  if( pWal->writeLock ){
+  if( ALWAYS(pWal->writeLock) ){
     Pgno iMax = pWal->hdr.mxFrame;
     Pgno iFrame;
   
@@ -42158,12 +43718,13 @@
     sqlite3Put4byte(&aWalHdr[4], WAL_MAX_VERSION);
     sqlite3Put4byte(&aWalHdr[8], szPage);
     sqlite3Put4byte(&aWalHdr[12], pWal->nCkpt);
+    sqlite3_randomness(8, pWal->hdr.aSalt);
     memcpy(&aWalHdr[16], pWal->hdr.aSalt, 8);
     walChecksumBytes(1, aWalHdr, WAL_HDRSIZE-2*4, 0, aCksum);
     sqlite3Put4byte(&aWalHdr[24], aCksum[0]);
     sqlite3Put4byte(&aWalHdr[28], aCksum[1]);
     
-    pWal->szPage = (u16)szPage;
+    pWal->szPage = szPage;
     pWal->hdr.bigEndCksum = SQLITE_BIGENDIAN;
     pWal->hdr.aFrameCksum[0] = aCksum[0];
     pWal->hdr.aFrameCksum[1] = aCksum[1];
@@ -42174,7 +43735,7 @@
       return rc;
     }
   }
-  assert( pWal->szPage==szPage );
+  assert( (int)pWal->szPage==szPage );
 
   /* Write the log file. */
   for(p=pList; p; p=p->pDirty){
@@ -42258,7 +43819,9 @@
 
   if( rc==SQLITE_OK ){
     /* Update the private copy of the header. */
-    pWal->hdr.szPage = (u16)szPage;
+    pWal->hdr.szPage = (u16)((szPage&0xff00) | (szPage>>16));
+    testcase( szPage<=32768 );
+    testcase( szPage>=65536 );
     pWal->hdr.mxFrame = iFrame;
     if( isCommit ){
       pWal->hdr.iChange++;
@@ -42470,7 +44033,7 @@
 **
 ** The file is divided into pages.  The first page is called page 1,
 ** the second is page 2, and so forth.  A page number of zero indicates
-** "no such page".  The page size can be any power of 2 between 512 and 32768.
+** "no such page".  The page size can be any power of 2 between 512 and 65536.
 ** Each page can be either a btree page, a freelist page, an overflow
 ** page, or a pointer-map page.
 **
@@ -42832,18 +44395,19 @@
   u8 pageSizeFixed;     /* True if the page size can no longer be changed */
   u8 secureDelete;      /* True if secure_delete is enabled */
   u8 initiallyEmpty;    /* Database is empty at start of transaction */
+  u8 openFlags;         /* Flags to sqlite3BtreeOpen() */
 #ifndef SQLITE_OMIT_AUTOVACUUM
   u8 autoVacuum;        /* True if auto-vacuum is enabled */
   u8 incrVacuum;        /* True if incr-vacuum is enabled */
 #endif
-  u16 pageSize;         /* Total number of bytes on a page */
-  u16 usableSize;       /* Number of usable bytes on each page */
   u16 maxLocal;         /* Maximum local payload in non-LEAFDATA tables */
   u16 minLocal;         /* Minimum local payload in non-LEAFDATA tables */
   u16 maxLeaf;          /* Maximum local payload in a LEAFDATA table */
   u16 minLeaf;          /* Minimum local payload in a LEAFDATA table */
   u8 inTransaction;     /* Transaction state */
   u8 doNotUseWAL;       /* If true, do not open write-ahead-log file */
+  u32 pageSize;         /* Total number of bytes on a page */
+  u32 usableSize;       /* Number of usable bytes on each page */
   int nTransaction;     /* Number of open transactions (read + write) */
   u32 nPage;            /* Number of pages in the database */
   void *pSchema;        /* Pointer to space allocated by sqlite3BtreeSchema() */
@@ -43442,7 +45006,16 @@
 # define TRACE(X)
 #endif
 
-
+/*
+** Extract a 2-byte big-endian integer from an array of unsigned bytes.
+** But if the value is zero, make it 65536.
+**
+** This routine is used to extract the "offset to cell content area" value
+** from the header of a btree page.  If the page size is 65536 and the page
+** is empty, the offset should be 65536, but the 2-byte value stores zero.
+** This routine makes the necessary adjustment to 65536.
+*/
+#define get2byteNotZero(X)  (((((int)get2byte(X))-1)&0xffff)+1)
 
 #ifndef SQLITE_OMIT_SHARED_CACHE
 /*
@@ -44131,11 +45704,16 @@
 ** Given a page number of a regular database page, return the page
 ** number for the pointer-map page that contains the entry for the
 ** input page number.
+**
+** Return 0 (not a valid page) for pgno==1 since there is
+** no pointer map associated with page 1.  The integrity_check logic
+** requires that ptrmapPageno(*,1)!=1.
 */
 static Pgno ptrmapPageno(BtShared *pBt, Pgno pgno){
   int nPagesPerMapPage;
   Pgno iPtrMap, ret;
   assert( sqlite3_mutex_held(pBt->mutex) );
+  if( pgno<2 ) return 0;
   nPagesPerMapPage = (pBt->usableSize/5)+1;
   iPtrMap = (pgno-2)/nPagesPerMapPage;
   ret = (iPtrMap*nPagesPerMapPage) + 2; 
@@ -44564,7 +46142,7 @@
   nFrag = data[hdr+7];
   assert( pPage->cellOffset == hdr + 12 - 4*pPage->leaf );
   gap = pPage->cellOffset + 2*pPage->nCell;
-  top = get2byte(&data[hdr+5]);
+  top = get2byteNotZero(&data[hdr+5]);
   if( gap>top ) return SQLITE_CORRUPT_BKPT;
   testcase( gap+2==top );
   testcase( gap+1==top );
@@ -44574,7 +46152,7 @@
     /* Always defragment highly fragmented pages */
     rc = defragmentPage(pPage);
     if( rc ) return rc;
-    top = get2byte(&data[hdr+5]);
+    top = get2byteNotZero(&data[hdr+5]);
   }else if( gap+2<=top ){
     /* Search the freelist looking for a free slot big enough to satisfy 
     ** the request. The allocation is made from the first free slot in 
@@ -44616,7 +46194,7 @@
   if( gap+2+nByte>top ){
     rc = defragmentPage(pPage);
     if( rc ) return rc;
-    top = get2byte(&data[hdr+5]);
+    top = get2byteNotZero(&data[hdr+5]);
     assert( gap+nByte<=top );
   }
 
@@ -44782,10 +46360,10 @@
     u8 hdr;            /* Offset to beginning of page header */
     u8 *data;          /* Equal to pPage->aData */
     BtShared *pBt;        /* The main btree structure */
-    u16 usableSize;    /* Amount of usable space on each page */
+    int usableSize;    /* Amount of usable space on each page */
     u16 cellOffset;    /* Offset from start of page to first cell pointer */
-    u16 nFree;         /* Number of unused bytes on the page */
-    u16 top;           /* First byte of the cell content area */
+    int nFree;         /* Number of unused bytes on the page */
+    int top;           /* First byte of the cell content area */
     int iCellFirst;    /* First allowable cell or freeblock offset */
     int iCellLast;     /* Last possible cell or freeblock offset */
 
@@ -44794,12 +46372,12 @@
     hdr = pPage->hdrOffset;
     data = pPage->aData;
     if( decodeFlags(pPage, data[hdr]) ) return SQLITE_CORRUPT_BKPT;
-    assert( pBt->pageSize>=512 && pBt->pageSize<=32768 );
-    pPage->maskPage = pBt->pageSize - 1;
+    assert( pBt->pageSize>=512 && pBt->pageSize<=65536 );
+    pPage->maskPage = (u16)(pBt->pageSize - 1);
     pPage->nOverflow = 0;
     usableSize = pBt->usableSize;
     pPage->cellOffset = cellOffset = hdr + 12 - 4*pPage->leaf;
-    top = get2byte(&data[hdr+5]);
+    top = get2byteNotZero(&data[hdr+5]);
     pPage->nCell = get2byte(&data[hdr+3]);
     if( pPage->nCell>MX_CELL(pBt) ){
       /* To many cells for a single page.  The page must be corrupt */
@@ -44898,13 +46476,13 @@
   memset(&data[hdr+1], 0, 4);
   data[hdr+7] = 0;
   put2byte(&data[hdr+5], pBt->usableSize);
-  pPage->nFree = pBt->usableSize - first;
+  pPage->nFree = (u16)(pBt->usableSize - first);
   decodeFlags(pPage, flags);
   pPage->hdrOffset = hdr;
   pPage->cellOffset = first;
   pPage->nOverflow = 0;
-  assert( pBt->pageSize>=512 && pBt->pageSize<=32768 );
-  pPage->maskPage = pBt->pageSize - 1;
+  assert( pBt->pageSize>=512 && pBt->pageSize<=65536 );
+  pPage->maskPage = (u16)(pBt->pageSize - 1);
   pPage->nCell = 0;
   pPage->isInit = 1;
 }
@@ -45068,11 +46646,20 @@
 ** Open a database file.
 ** 
 ** zFilename is the name of the database file.  If zFilename is NULL
-** a new database with a random name is created.  This randomly named
-** database file will be deleted when sqlite3BtreeClose() is called.
+** then an ephemeral database is created.  The ephemeral database might
+** be exclusively in memory, or it might use a disk-based memory cache.
+** Either way, the ephemeral database will be automatically deleted 
+** when sqlite3BtreeClose() is called.
+**
 ** If zFilename is ":memory:" then an in-memory database is created
 ** that is automatically destroyed when it is closed.
 **
+** The "flags" parameter is a bitmask that might contain bits
+** BTREE_OMIT_JOURNAL and/or BTREE_NO_READLOCK.  The BTREE_NO_READLOCK
+** bit is also set if the SQLITE_NoReadlock flags is set in db->flags.
+** These flags are passed through into sqlite3PagerOpen() and must
+** be the same values as PAGER_OMIT_JOURNAL and PAGER_NO_READLOCK.
+**
 ** If the database is already opened in the same database connection
 ** and we are in shared cache mode, then the open will fail with an
 ** SQLITE_CONSTRAINT error.  We cannot allow two or more BtShared
@@ -45094,6 +46681,9 @@
   u8 nReserve;                   /* Byte of unused space on each page */
   unsigned char zDbHeader[100];  /* Database header content */
 
+  /* True if opening an ephemeral, temporary database */
+  const int isTempDb = zFilename==0 || zFilename[0]==0;
+
   /* Set the variable isMemdb to true for an in-memory database, or 
   ** false for a file-based database. This symbol is only required if
   ** either of the shared-data or autovacuum features are compiled 
@@ -45103,13 +46693,30 @@
   #ifdef SQLITE_OMIT_MEMORYDB
     const int isMemdb = 0;
   #else
-    const int isMemdb = zFilename && !strcmp(zFilename, ":memory:");
+    const int isMemdb = (zFilename && strcmp(zFilename, ":memory:")==0)
+                         || (isTempDb && sqlite3TempInMemory(db));
   #endif
 #endif
 
   assert( db!=0 );
   assert( sqlite3_mutex_held(db->mutex) );
+  assert( (flags&0xff)==flags );   /* flags fit in 8 bits */
 
+  /* Only a BTREE_SINGLE database can be BTREE_UNORDERED */
+  assert( (flags & BTREE_UNORDERED)==0 || (flags & BTREE_SINGLE)!=0 );
+
+  /* A BTREE_SINGLE database is always a temporary and/or ephemeral */
+  assert( (flags & BTREE_SINGLE)==0 || isTempDb );
+
+  if( db->flags & SQLITE_NoReadlock ){
+    flags |= BTREE_NO_READLOCK;
+  }
+  if( isMemdb ){
+    flags |= BTREE_MEMORY;
+  }
+  if( (vfsFlags & SQLITE_OPEN_MAIN_DB)!=0 && (isMemdb || isTempDb) ){
+    vfsFlags = (vfsFlags & ~SQLITE_OPEN_MAIN_DB) | SQLITE_OPEN_TEMP_DB;
+  }
   pVfs = db->pVfs;
   p = sqlite3MallocZero(sizeof(Btree));
   if( !p ){
@@ -45127,7 +46734,7 @@
   ** If this Btree is a candidate for shared cache, try to find an
   ** existing BtShared object that we can share with
   */
-  if( isMemdb==0 && zFilename && zFilename[0] ){
+  if( isMemdb==0 && isTempDb==0 ){
     if( vfsFlags & SQLITE_OPEN_SHAREDCACHE ){
       int nFullPathname = pVfs->mxPathname+1;
       char *zFullPathname = sqlite3Malloc(nFullPathname);
@@ -45202,6 +46809,7 @@
     if( rc!=SQLITE_OK ){
       goto btree_open_out;
     }
+    pBt->openFlags = (u8)flags;
     pBt->db = db;
     sqlite3PagerSetBusyhandler(pBt->pPager, btreeInvokeBusyHandler, pBt);
     p->pBt = pBt;
@@ -45212,7 +46820,7 @@
 #ifdef SQLITE_SECURE_DELETE
     pBt->secureDelete = 1;
 #endif
-    pBt->pageSize = get2byte(&zDbHeader[16]);
+    pBt->pageSize = (zDbHeader[16]<<8) | (zDbHeader[17]<<16);
     if( pBt->pageSize<512 || pBt->pageSize>SQLITE_MAX_PAGE_SIZE
          || ((pBt->pageSize-1)&pBt->pageSize)!=0 ){
       pBt->pageSize = 0;
@@ -45306,6 +46914,14 @@
     sqlite3_free(pBt);
     sqlite3_free(p);
     *ppBtree = 0;
+  }else{
+    /* If the B-Tree was successfully opened, set the pager-cache size to the
+    ** default value. Except, when opening on an existing shared pager-cache,
+    ** do not change the pager-cache size.
+    */
+    if( sqlite3BtreeSchema(p, 0, 0)==0 ){
+      sqlite3PagerSetCachesize(p->pBt->pPager, SQLITE_DEFAULT_CACHE_SIZE);
+    }
   }
   if( mutexOpen ){
     assert( sqlite3_mutex_held(mutexOpen) );
@@ -45414,7 +47030,7 @@
     if( pBt->xFreeSchema && pBt->pSchema ){
       pBt->xFreeSchema(pBt->pSchema);
     }
-    sqlite3_free(pBt->pSchema);
+    sqlite3DbFree(0, pBt->pSchema);
     freeTempSpace(pBt);
     sqlite3_free(pBt);
   }
@@ -45526,7 +47142,7 @@
         ((pageSize-1)&pageSize)==0 ){
     assert( (pageSize & 7)==0 );
     assert( !pBt->pPage1 && !pBt->pCursor );
-    pBt->pageSize = (u16)pageSize;
+    pBt->pageSize = (u32)pageSize;
     freeTempSpace(pBt);
   }
   rc = sqlite3PagerSetPagesize(pBt->pPager, &pBt->pageSize, nReserve);
@@ -45661,15 +47277,13 @@
   ** a valid database file. 
   */
   nPage = nPageHeader = get4byte(28+(u8*)pPage1->aData);
-  if( (rc = sqlite3PagerPagecount(pBt->pPager, &nPageFile))!=SQLITE_OK ){;
-    goto page1_init_failed;
-  }
+  sqlite3PagerPagecount(pBt->pPager, &nPageFile);
   if( nPage==0 || memcmp(24+(u8*)pPage1->aData, 92+(u8*)pPage1->aData,4)!=0 ){
     nPage = nPageFile;
   }
   if( nPage>0 ){
-    int pageSize;
-    int usableSize;
+    u32 pageSize;
+    u32 usableSize;
     u8 *page1 = pPage1->aData;
     rc = SQLITE_NOTADB;
     if( memcmp(page1, zMagicHeader, 16)!=0 ){
@@ -45720,15 +47334,16 @@
     if( memcmp(&page1[21], "\100\040\040",3)!=0 ){
       goto page1_init_failed;
     }
-    pageSize = get2byte(&page1[16]);
-    if( ((pageSize-1)&pageSize)!=0 || pageSize<512 ||
-        (SQLITE_MAX_PAGE_SIZE<32768 && pageSize>SQLITE_MAX_PAGE_SIZE)
+    pageSize = (page1[16]<<8) | (page1[17]<<16);
+    if( ((pageSize-1)&pageSize)!=0
+     || pageSize>SQLITE_MAX_PAGE_SIZE 
+     || pageSize<=256 
     ){
       goto page1_init_failed;
     }
     assert( (pageSize & 7)==0 );
     usableSize = pageSize - page1[20];
-    if( pageSize!=pBt->pageSize ){
+    if( (u32)pageSize!=pBt->pageSize ){
       /* After reading the first page of the database assuming a page size
       ** of BtShared.pageSize, we have discovered that the page-size is
       ** actually pageSize. Unlock the database, leave pBt->pPage1 at
@@ -45736,8 +47351,8 @@
       ** again with the correct page-size.
       */
       releasePage(pPage1);
-      pBt->usableSize = (u16)usableSize;
-      pBt->pageSize = (u16)pageSize;
+      pBt->usableSize = usableSize;
+      pBt->pageSize = pageSize;
       freeTempSpace(pBt);
       rc = sqlite3PagerSetPagesize(pBt->pPager, &pBt->pageSize,
                                    pageSize-usableSize);
@@ -45750,8 +47365,8 @@
     if( usableSize<480 ){
       goto page1_init_failed;
     }
-    pBt->pageSize = (u16)pageSize;
-    pBt->usableSize = (u16)usableSize;
+    pBt->pageSize = pageSize;
+    pBt->usableSize = usableSize;
 #ifndef SQLITE_OMIT_AUTOVACUUM
     pBt->autoVacuum = (get4byte(&page1[36 + 4*4])?1:0);
     pBt->incrVacuum = (get4byte(&page1[36 + 7*4])?1:0);
@@ -45767,14 +47382,14 @@
   **     9-byte nKey value
   **     4-byte nData value
   **     4-byte overflow page pointer
-  ** So a cell consists of a 2-byte poiner, a header which is as much as
+  ** So a cell consists of a 2-byte pointer, a header which is as much as
   ** 17 bytes long, 0 to N bytes of payload, and an optional 4 byte overflow
   ** page pointer.
   */
-  pBt->maxLocal = (pBt->usableSize-12)*64/255 - 23;
-  pBt->minLocal = (pBt->usableSize-12)*32/255 - 23;
-  pBt->maxLeaf = pBt->usableSize - 35;
-  pBt->minLeaf = (pBt->usableSize-12)*32/255 - 23;
+  pBt->maxLocal = (u16)((pBt->usableSize-12)*64/255 - 23);
+  pBt->minLocal = (u16)((pBt->usableSize-12)*32/255 - 23);
+  pBt->maxLeaf = (u16)(pBt->usableSize - 35);
+  pBt->minLeaf = (u16)((pBt->usableSize-12)*32/255 - 23);
   assert( pBt->maxLeaf + 23 <= MX_CELL_SIZE(pBt) );
   pBt->pPage1 = pPage1;
   pBt->nPage = nPage;
@@ -45827,7 +47442,8 @@
   if( rc ) return rc;
   memcpy(data, zMagicHeader, sizeof(zMagicHeader));
   assert( sizeof(zMagicHeader)==16 );
-  put2byte(&data[16], pBt->pageSize);
+  data[16] = (u8)((pBt->pageSize>>8)&0xff);
+  data[17] = (u8)((pBt->pageSize>>16)&0xff);
   data[18] = 1;
   data[19] = 1;
   assert( pBt->usableSize<=pBt->pageSize && pBt->usableSize+255>=pBt->pageSize);
@@ -45979,13 +47595,27 @@
     if( p->inTrans>pBt->inTransaction ){
       pBt->inTransaction = p->inTrans;
     }
-#ifndef SQLITE_OMIT_SHARED_CACHE
     if( wrflag ){
+      MemPage *pPage1 = pBt->pPage1;
+#ifndef SQLITE_OMIT_SHARED_CACHE
       assert( !pBt->pWriter );
       pBt->pWriter = p;
       pBt->isExclusive = (u8)(wrflag>1);
-    }
 #endif
+
+      /* If the db-size header field is incorrect (as it may be if an old
+      ** client has been writing the database file), update it now. Doing
+      ** this sooner rather than later means the database size can safely 
+      ** re-read the database size from page 1 if a savepoint or transaction
+      ** rollback occurs within the transaction.
+      */
+      if( pBt->nPage!=get4byte(&pPage1->aData[28]) ){
+        rc = sqlite3PagerWrite(pPage1->pDbPage);
+        if( rc==SQLITE_OK ){
+          put4byte(&pPage1->aData[28], pBt->nPage);
+        }
+      }
+    }
   }
 
 
@@ -46724,9 +48354,11 @@
       if( iSavepoint<0 && pBt->initiallyEmpty ) pBt->nPage = 0;
       rc = newDatabase(pBt);
       pBt->nPage = get4byte(28 + pBt->pPage1->aData);
-      if( pBt->nPage==0 ){
-        sqlite3PagerPagecount(pBt->pPager, (int*)&pBt->nPage);
-      }
+
+      /* The database size was written into the offset 28 of the header
+      ** when the transaction started, so we know that the value at offset
+      ** 28 is nonzero. */
+      assert( pBt->nPage>0 );
     }
     sqlite3BtreeLeave(p);
   }
@@ -47822,9 +49454,9 @@
         pCur->validNKey = 1;
         pCur->info.nKey = nCellKey;
       }else{
-        /* The maximum supported page-size is 32768 bytes. This means that
+        /* The maximum supported page-size is 65536 bytes. This means that
         ** the maximum number of record bytes stored on an index B-Tree
-        ** page is at most 8198 bytes, which may be stored as a 2-byte
+        ** page is less than 16384 bytes and may be stored as a 2-byte
         ** varint. This information is used to attempt to avoid parsing 
         ** the entire cell by checking for the cases where the record is 
         ** stored entirely within the b-tree page by inspecting the first 
@@ -48187,6 +49819,10 @@
           if( !pPrevTrunk ){
             memcpy(&pPage1->aData[32], &pTrunk->aData[0], 4);
           }else{
+            rc = sqlite3PagerWrite(pPrevTrunk->pDbPage);
+            if( rc!=SQLITE_OK ){
+              goto end_allocate_page;
+            }
             memcpy(&pPrevTrunk->aData[0], &pTrunk->aData[0], 4);
           }
         }else{
@@ -48493,7 +50129,7 @@
   Pgno ovflPgno;
   int rc;
   int nOvfl;
-  u16 ovflPageSize;
+  u32 ovflPageSize;
 
   assert( sqlite3_mutex_held(pPage->pBt->mutex) );
   btreeParseCellPtr(pPage, pCell, &info);
@@ -48718,7 +50354,7 @@
 */
 static void dropCell(MemPage *pPage, int idx, int sz, int *pRC){
   int i;          /* Loop counter */
-  int pc;         /* Offset to cell content of cell being deleted */
+  u32 pc;         /* Offset to cell content of cell being deleted */
   u8 *data;       /* pPage->aData */
   u8 *ptr;        /* Used to move bytes around within data[] */
   int rc;         /* The return code */
@@ -48736,7 +50372,7 @@
   hdr = pPage->hdrOffset;
   testcase( pc==get2byte(&data[hdr+5]) );
   testcase( pc+sz==pPage->pBt->usableSize );
-  if( pc < get2byte(&data[hdr+5]) || pc+sz > pPage->pBt->usableSize ){
+  if( pc < (u32)get2byte(&data[hdr+5]) || pc+sz > pPage->pBt->usableSize ){
     *pRC = SQLITE_CORRUPT_BKPT;
     return;
   }
@@ -48793,7 +50429,7 @@
   if( *pRC ) return;
 
   assert( i>=0 && i<=pPage->nCell+pPage->nOverflow );
-  assert( pPage->nCell<=MX_CELL(pPage->pBt) && MX_CELL(pPage->pBt)<=5460 );
+  assert( pPage->nCell<=MX_CELL(pPage->pBt) && MX_CELL(pPage->pBt)<=10921 );
   assert( pPage->nOverflow<=ArraySize(pPage->aOvfl) );
   assert( sqlite3_mutex_held(pPage->pBt->mutex) );
   /* The cell should normally be sized correctly.  However, when moving a
@@ -48873,12 +50509,12 @@
 
   assert( pPage->nOverflow==0 );
   assert( sqlite3_mutex_held(pPage->pBt->mutex) );
-  assert( nCell>=0 && nCell<=MX_CELL(pPage->pBt) && MX_CELL(pPage->pBt)<=5460 );
+  assert( nCell>=0 && nCell<=MX_CELL(pPage->pBt) && MX_CELL(pPage->pBt)<=10921);
   assert( sqlite3PagerIswriteable(pPage->pDbPage) );
 
   /* Check that the page has just been zeroed by zeroPage() */
   assert( pPage->nCell==0 );
-  assert( get2byte(&data[hdr+5])==nUsable );
+  assert( get2byteNotZero(&data[hdr+5])==nUsable );
 
   pCellptr = &data[pPage->cellOffset + nCell*2];
   cellbody = nUsable;
@@ -48944,6 +50580,7 @@
   assert( sqlite3PagerIswriteable(pParent->pDbPage) );
   assert( pPage->nOverflow==1 );
 
+  /* This error condition is now caught prior to reaching this function */
   if( pPage->nCell<=0 ) return SQLITE_CORRUPT_BKPT;
 
   /* Allocate a new page. This page will become the right-sibling of 
@@ -49273,7 +50910,7 @@
       ** is allocated.  */
       if( pBt->secureDelete ){
         int iOff = SQLITE_PTR_TO_INT(apDiv[i]) - SQLITE_PTR_TO_INT(pParent->aData);
-        if( (iOff+szNew[i])>pBt->usableSize ){
+        if( (iOff+szNew[i])>(int)pBt->usableSize ){
           rc = SQLITE_CORRUPT_BKPT;
           memset(apOld, 0, (i+1)*sizeof(MemPage*));
           goto balance_cleanup;
@@ -49352,7 +50989,7 @@
       szCell[nCell] = sz;
       pTemp = &aSpace1[iSpace1];
       iSpace1 += sz;
-      assert( sz<=pBt->pageSize/4 );
+      assert( sz<=pBt->maxLocal+23 );
       assert( iSpace1<=pBt->pageSize );
       memcpy(pTemp, apDiv[i], sz);
       apCell[nCell] = pTemp+leafCorrection;
@@ -49598,7 +51235,7 @@
         }
       }
       iOvflSpace += sz;
-      assert( sz<=pBt->pageSize/4 );
+      assert( sz<=pBt->maxLocal+23 );
       assert( iOvflSpace<=pBt->pageSize );
       insertCell(pParent, nxDiv, pCell, sz, pTemp, pNew->pgno, &rc);
       if( rc!=SQLITE_OK ) goto balance_cleanup;
@@ -50235,11 +51872,12 @@
 **     BTREE_INTKEY|BTREE_LEAFDATA     Used for SQL tables with rowid keys
 **     BTREE_ZERODATA                  Used for SQL indices
 */
-static int btreeCreateTable(Btree *p, int *piTable, int flags){
+static int btreeCreateTable(Btree *p, int *piTable, int createTabFlags){
   BtShared *pBt = p->pBt;
   MemPage *pRoot;
   Pgno pgnoRoot;
   int rc;
+  int ptfFlags;          /* Page-type flage for the root page of new table */
 
   assert( sqlite3BtreeHoldsMutex(p) );
   assert( pBt->inTransaction==TRANS_WRITE );
@@ -50358,8 +51996,14 @@
   }
 #endif
   assert( sqlite3PagerIswriteable(pRoot->pDbPage) );
-  zeroPage(pRoot, flags | PTF_LEAF);
+  if( createTabFlags & BTREE_INTKEY ){
+    ptfFlags = PTF_INTKEY | PTF_LEAFDATA | PTF_LEAF;
+  }else{
+    ptfFlags = PTF_ZERODATA | PTF_LEAF;
+  }
+  zeroPage(pRoot, ptfFlags);
   sqlite3PagerUnref(pRoot->pDbPage);
+  assert( (pBt->openFlags & BTREE_SINGLE)==0 || pgnoRoot==2 );
   *piTable = (int)pgnoRoot;
   return SQLITE_OK;
 }
@@ -50842,7 +52486,7 @@
         checkPtrmap(pCheck, iPage, PTRMAP_FREEPAGE, 0, zContext);
       }
 #endif
-      if( n>pCheck->pBt->usableSize/4-2 ){
+      if( n>(int)pCheck->pBt->usableSize/4-2 ){
         checkAppendMsg(pCheck, zContext,
            "freelist leaf count too big on page %d", iPage);
         N--;
@@ -51053,7 +52697,7 @@
   if( hit==0 ){
     pCheck->mallocFailed = 1;
   }else{
-    u16 contentOffset = get2byte(&data[hdr+5]);
+    int contentOffset = get2byteNotZero(&data[hdr+5]);
     assert( contentOffset<=usableSize );  /* Enforced by btreeInitPage() */
     memset(hit+contentOffset, 0, usableSize-contentOffset);
     memset(hit, 1, contentOffset);
@@ -51061,12 +52705,12 @@
     cellStart = hdr + 12 - 4*pPage->leaf;
     for(i=0; i<nCell; i++){
       int pc = get2byte(&data[cellStart+i*2]);
-      u16 size = 1024;
+      u32 size = 65536;
       int j;
       if( pc<=usableSize-4 ){
         size = cellSizePtr(pPage, &data[pc]);
       }
-      if( (pc+size-1)>=usableSize ){
+      if( (int)(pc+size-1)>=usableSize ){
         checkAppendMsg(pCheck, 0, 
             "Corruption detected in cell %d on page %d",i,iPage);
       }else{
@@ -51159,6 +52803,7 @@
     sCheck.anRef[i] = 1;
   }
   sqlite3StrAccumInit(&sCheck.errMsg, zErr, sizeof(zErr), 20000);
+  sCheck.errMsg.useMalloc = 2;
 
   /* Check the integrity of the freelist
   */
@@ -51257,6 +52902,29 @@
   return (p && (p->inTrans==TRANS_WRITE));
 }
 
+#ifndef SQLITE_OMIT_WAL
+/*
+** Run a checkpoint on the Btree passed as the first argument.
+**
+** Return SQLITE_LOCKED if this or any other connection has an open 
+** transaction on the shared-cache the argument Btree is connected to.
+*/
+SQLITE_PRIVATE int sqlite3BtreeCheckpoint(Btree *p){
+  int rc = SQLITE_OK;
+  if( p ){
+    BtShared *pBt = p->pBt;
+    sqlite3BtreeEnter(p);
+    if( pBt->inTransaction!=TRANS_NONE ){
+      rc = SQLITE_LOCKED;
+    }else{
+      rc = sqlite3PagerCheckpoint(pBt->pPager);
+    }
+    sqlite3BtreeLeave(p);
+  }
+  return rc;
+}
+#endif
+
 /*
 ** Return non-zero if a read (or write) transaction is active.
 */
@@ -51296,7 +52964,7 @@
   BtShared *pBt = p->pBt;
   sqlite3BtreeEnter(p);
   if( !pBt->pSchema && nBytes ){
-    pBt->pSchema = sqlite3MallocZero(nBytes);
+    pBt->pSchema = sqlite3DbMallocZero(0, nBytes);
     pBt->xFreeSchema = xFree;
   }
   sqlite3BtreeLeave(p);
@@ -51595,7 +53263,10 @@
     );
     p = 0;
   }else {
-    /* Allocate space for a new sqlite3_backup object */
+    /* Allocate space for a new sqlite3_backup object...
+    ** EVIDENCE-OF: R-64852-21591 The sqlite3_backup object is created by a
+    ** call to sqlite3_backup_init() and is destroyed by a call to
+    ** sqlite3_backup_finish(). */
     p = (sqlite3_backup *)sqlite3_malloc(sizeof(sqlite3_backup));
     if( !p ){
       sqlite3Error(pDestDb, SQLITE_NOMEM, 0);
@@ -51666,6 +53337,15 @@
     rc = SQLITE_READONLY;
   }
 
+#ifdef SQLITE_HAS_CODEC
+  /* Backup is not possible if the page size of the destination is changing
+  ** a a codec is in use.
+  */
+  if( nSrcPgsz!=nDestPgsz && sqlite3PagerGetCodec(pDestPager)!=0 ){
+    rc = SQLITE_READONLY;
+  }
+#endif
+
   /* This loop runs once for each destination page spanned by the source 
   ** page. For each iteration, variable iOff is set to the byte offset
   ** of the destination page.
@@ -51969,6 +53649,9 @@
   }
   sqlite3BtreeLeave(p->pSrc);
   if( p->pDestDb ){
+    /* EVIDENCE-OF: R-64852-21591 The sqlite3_backup object is created by a
+    ** call to sqlite3_backup_init() and is destroyed by a call to
+    ** sqlite3_backup_finish(). */
     sqlite3_free(p);
   }
   sqlite3_mutex_leave(mutex);
@@ -52220,6 +53903,9 @@
     pMem->z[pMem->n] = 0;
     pMem->z[pMem->n+1] = 0;
     pMem->flags |= MEM_Term;
+#ifdef SQLITE_DEBUG
+    pMem->pScopyFrom = 0;
+#endif
   }
 
   return SQLITE_OK;
@@ -52340,7 +54026,7 @@
     ctx.s.db = pMem->db;
     ctx.pMem = pMem;
     ctx.pFunc = pFunc;
-    pFunc->xFinalize(&ctx);
+    pFunc->xFinalize(&ctx); /* IMP: R-24505-23230 */
     assert( 0==(pMem->flags&MEM_Dyn) && !pMem->xDel );
     sqlite3DbFree(pMem->db, pMem->zMalloc);
     memcpy(pMem, &ctx.s, sizeof(ctx.s));
@@ -52681,6 +54367,28 @@
   return 0; 
 }
 
+#ifdef SQLITE_DEBUG
+/*
+** This routine prepares a memory cell for modication by breaking
+** its link to a shallow copy and by marking any current shallow
+** copies of this cell as invalid.
+**
+** This is used for testing and debugging only - to make sure shallow
+** copies are not misused.
+*/
+SQLITE_PRIVATE void sqlite3VdbeMemPrepareToChange(Vdbe *pVdbe, Mem *pMem){
+  int i;
+  Mem *pX;
+  for(i=1, pX=&pVdbe->aMem[1]; i<=pVdbe->nMem; i++, pX++){
+    if( pX->pScopyFrom==pMem ){
+      pX->flags |= MEM_Invalid;
+      pX->pScopyFrom = 0;
+    }
+  }
+  pMem->pScopyFrom = 0;
+}
+#endif /* SQLITE_DEBUG */
+
 /*
 ** Size of struct Mem not including the Mem.zMalloc member.
 */
@@ -53049,7 +54757,7 @@
         return 0;
       }
     }
-    sqlite3VdbeMemNulTerminate(pVal);
+    sqlite3VdbeMemNulTerminate(pVal); /* IMP: R-59893-45467 */
   }else{
     assert( (pVal->flags&MEM_Blob)==0 );
     sqlite3VdbeMemStringify(pVal, enc);
@@ -53104,7 +54812,7 @@
   }
   op = pExpr->op;
 
-  /* op can only be TK_REGISTER is we have compiled with SQLITE_ENABLE_STAT2.
+  /* op can only be TK_REGISTER if we have compiled with SQLITE_ENABLE_STAT2.
   ** The ifdef here is to enable us to achieve 100% branch test coverage even
   ** when SQLITE_ENABLE_STAT2 is omitted.
   */
@@ -53782,15 +55490,17 @@
   }
 }
 
+static void vdbeFreeOpArray(sqlite3 *, Op *, int);
+
 /*
 ** Delete a P4 value if necessary.
 */
 static void freeP4(sqlite3 *db, int p4type, void *p4){
   if( p4 ){
+    assert( db );
     switch( p4type ){
       case P4_REAL:
       case P4_INT64:
-      case P4_MPRINTF:
       case P4_DYNAMIC:
       case P4_KEYINFO:
       case P4_INTARRAY:
@@ -53798,10 +55508,14 @@
         sqlite3DbFree(db, p4);
         break;
       }
+      case P4_MPRINTF: {
+        if( db->pnBytesFreed==0 ) sqlite3_free(p4);
+        break;
+      }
       case P4_VDBEFUNC: {
         VdbeFunc *pVdbeFunc = (VdbeFunc *)p4;
         freeEphemeralFunction(db, pVdbeFunc->pFunc);
-        sqlite3VdbeDeleteAuxData(pVdbeFunc, 0);
+        if( db->pnBytesFreed==0 ) sqlite3VdbeDeleteAuxData(pVdbeFunc, 0);
         sqlite3DbFree(db, pVdbeFunc);
         break;
       }
@@ -53810,15 +55524,17 @@
         break;
       }
       case P4_MEM: {
-        sqlite3ValueFree((sqlite3_value*)p4);
+        if( db->pnBytesFreed==0 ){
+          sqlite3ValueFree((sqlite3_value*)p4);
+        }else{
+          Mem *p = (Mem*)p4;
+          sqlite3DbFree(db, p->zMalloc);
+          sqlite3DbFree(db, p);
+        }
         break;
       }
       case P4_VTAB : {
-        sqlite3VtabUnlock((VTable *)p4);
-        break;
-      }
-      case P4_SUBPROGRAM : {
-        sqlite3VdbeProgramDelete(db, (SubProgram *)p4, 1);
+        if( db->pnBytesFreed==0 ) sqlite3VtabUnlock((VTable *)p4);
         break;
       }
     }
@@ -53844,35 +55560,15 @@
 }
 
 /*
-** Decrement the ref-count on the SubProgram structure passed as the
-** second argument. If the ref-count reaches zero, free the structure.
-**
-** The array of VDBE opcodes stored as SubProgram.aOp is freed if
-** either the ref-count reaches zero or parameter freeop is non-zero.
-**
-** Since the array of opcodes pointed to by SubProgram.aOp may directly
-** or indirectly contain a reference to the SubProgram structure itself.
-** By passing a non-zero freeop parameter, the caller may ensure that all
-** SubProgram structures and their aOp arrays are freed, even when there
-** are such circular references.
+** Link the SubProgram object passed as the second argument into the linked
+** list at Vdbe.pSubProgram. This list is used to delete all sub-program
+** objects when the VM is no longer required.
 */
-SQLITE_PRIVATE void sqlite3VdbeProgramDelete(sqlite3 *db, SubProgram *p, int freeop){
-  if( p ){
-    assert( p->nRef>0 );
-    if( freeop || p->nRef==1 ){
-      Op *aOp = p->aOp;
-      p->aOp = 0;
-      vdbeFreeOpArray(db, aOp, p->nOp);
-      p->nOp = 0;
-    }
-    p->nRef--;
-    if( p->nRef==0 ){
-      sqlite3DbFree(db, p);
-    }
-  }
+SQLITE_PRIVATE void sqlite3VdbeLinkSubProgram(Vdbe *pVdbe, SubProgram *p){
+  p->pNext = pVdbe->pProgram;
+  pVdbe->pProgram = p;
 }
 
-
 /*
 ** Change N opcodes starting at addr to No-ops.
 */
@@ -53948,7 +55644,7 @@
 
     nField = ((KeyInfo*)zP4)->nField;
     nByte = sizeof(*pKeyInfo) + (nField-1)*sizeof(pKeyInfo->aColl[0]) + nField;
-    pKeyInfo = sqlite3Malloc( nByte );
+    pKeyInfo = sqlite3DbMallocRaw(0, nByte);
     pOp->p4.pKeyInfo = pKeyInfo;
     if( pKeyInfo ){
       u8 *aSortOrder;
@@ -54212,6 +55908,12 @@
     Mem *pEnd;
     sqlite3 *db = p->db;
     u8 malloc_failed = db->mallocFailed;
+    if( db->pnBytesFreed ){
+      for(pEnd=&p[N]; p<pEnd; p++){
+        sqlite3DbFree(db, p->zMalloc);
+      }
+      return;
+    }
     for(pEnd=&p[N]; p<pEnd; p++){
       assert( (&p[1])==pEnd || p[0].db==p[1].db );
 
@@ -54861,9 +56563,6 @@
   ** to the transaction.
   */
   rc = sqlite3VtabSync(db, &p->zErrMsg);
-  if( rc!=SQLITE_OK ){
-    return rc;
-  }
 
   /* This loop determines (a) if the commit hook should be invoked and
   ** (b) how many database files have open write transactions, not 
@@ -54871,13 +56570,17 @@
   ** one database file has an open write transaction, a master journal
   ** file is required for an atomic commit.
   */ 
-  for(i=0; i<db->nDb; i++){ 
+  for(i=0; rc==SQLITE_OK && i<db->nDb; i++){ 
     Btree *pBt = db->aDb[i].pBt;
     if( sqlite3BtreeIsInTrans(pBt) ){
       needXcommit = 1;
       if( i!=1 ) nTrans++;
+      rc = sqlite3PagerExclusiveLock(sqlite3BtreePager(pBt));
     }
   }
+  if( rc!=SQLITE_OK ){
+    return rc;
+  }
 
   /* If there are any write-transactions at all, invoke the commit hook */
   if( needXcommit && db->xCommitCallback ){
@@ -54969,9 +56672,10 @@
       Btree *pBt = db->aDb[i].pBt;
       if( sqlite3BtreeIsInTrans(pBt) ){
         char const *zFile = sqlite3BtreeGetJournalname(pBt);
-        if( zFile==0 || zFile[0]==0 ){
+        if( zFile==0 ){
           continue;  /* Ignore TEMP and :memory: databases */
         }
+        assert( zFile[0]!=0 );
         if( !needSync && !sqlite3BtreeSyncDisabled(pBt) ){
           needSync = 1;
         }
@@ -55016,6 +56720,7 @@
       }
     }
     sqlite3OsCloseFree(pMaster);
+    assert( rc!=SQLITE_BUSY );
     if( rc!=SQLITE_OK ){
       sqlite3DbFree(db, zMaster);
       return rc;
@@ -55274,8 +56979,17 @@
     isSpecialError = mrc==SQLITE_NOMEM || mrc==SQLITE_IOERR
                      || mrc==SQLITE_INTERRUPT || mrc==SQLITE_FULL;
     if( isSpecialError ){
-      /* If the query was read-only, we need do no rollback at all. Otherwise,
-      ** proceed with the special handling.
+      /* If the query was read-only and the error code is SQLITE_INTERRUPT, 
+      ** no rollback is necessary. Otherwise, at least a savepoint 
+      ** transaction must be rolled back to restore the database to a 
+      ** consistent state.
+      **
+      ** Even if the statement is read-only, it is important to perform
+      ** a statement or transaction rollback operation. If the error 
+      ** occured while writing to the journal, sub-journal or database
+      ** file as part of an effort to free up cache space (see function
+      ** pagerStress() in pager.c), the rollback is required to restore 
+      ** the pager to a consistent state.
       */
       if( !p->readOnly || mrc!=SQLITE_INTERRUPT ){
         if( (mrc==SQLITE_NOMEM || mrc==SQLITE_FULL) && p->usesStmtJournal ){
@@ -55545,6 +57259,30 @@
 }
 
 /*
+** Free all memory associated with the Vdbe passed as the second argument.
+** The difference between this function and sqlite3VdbeDelete() is that
+** VdbeDelete() also unlinks the Vdbe from the list of VMs associated with
+** the database connection.
+*/
+SQLITE_PRIVATE void sqlite3VdbeDeleteObject(sqlite3 *db, Vdbe *p){
+  SubProgram *pSub, *pNext;
+  assert( p->db==0 || p->db==db );
+  releaseMemArray(p->aVar, p->nVar);
+  releaseMemArray(p->aColName, p->nResColumn*COLNAME_N);
+  for(pSub=p->pProgram; pSub; pSub=pNext){
+    pNext = pSub->pNext;
+    vdbeFreeOpArray(db, pSub->aOp, pSub->nOp);
+    sqlite3DbFree(db, pSub);
+  }
+  vdbeFreeOpArray(db, p->aOp, p->nOp);
+  sqlite3DbFree(db, p->aLabel);
+  sqlite3DbFree(db, p->aColName);
+  sqlite3DbFree(db, p->zSql);
+  sqlite3DbFree(db, p->pFree);
+  sqlite3DbFree(db, p);
+}
+
+/*
 ** Delete an entire VDBE.
 */
 SQLITE_PRIVATE void sqlite3VdbeDelete(Vdbe *p){
@@ -55561,16 +57299,9 @@
   if( p->pNext ){
     p->pNext->pPrev = p->pPrev;
   }
-  releaseMemArray(p->aVar, p->nVar);
-  releaseMemArray(p->aColName, p->nResColumn*COLNAME_N);
-  vdbeFreeOpArray(db, p->aOp, p->nOp);
-  sqlite3DbFree(db, p->aLabel);
-  sqlite3DbFree(db, p->aColName);
-  sqlite3DbFree(db, p->zSql);
   p->magic = VDBE_MAGIC_DEAD;
-  sqlite3DbFree(db, p->pFree);
   p->db = 0;
-  sqlite3DbFree(db, p);
+  sqlite3VdbeDeleteObject(db, p);
 }
 
 /*
@@ -55596,11 +57327,8 @@
     rc = sqlite3BtreeMovetoUnpacked(p->pCursor, 0, p->movetoTarget, 0, &res);
     if( rc ) return rc;
     p->lastRowid = p->movetoTarget;
-    p->rowidIsValid = ALWAYS(res==0) ?1:0;
-    if( NEVER(res<0) ){
-      rc = sqlite3BtreeNext(p->pCursor, &res);
-      if( rc ) return rc;
-    }
+    if( res!=0 ) return SQLITE_CORRUPT_BKPT;
+    p->rowidIsValid = 1;
 #ifdef SQLITE_TEST
     sqlite3_search_count++;
 #endif
@@ -56487,7 +58215,7 @@
     sqlite3VdbeMemExpandBlob(p);
     p->flags &= ~MEM_Str;
     p->flags |= MEM_Blob;
-    return p->z;
+    return p->n ? p->z : 0;
   }else{
     return sqlite3_value_text(pVal);
   }
@@ -56744,7 +58472,7 @@
   if( rc!=SQLITE_ROW && db->xProfile && !db->init.busy && p->zSql ){
     sqlite3_int64 iNow;
     sqlite3OsCurrentTimeInt64(db->pVfs, &iNow);
-    db->xProfile(db->pProfileArg, p->zSql, iNow - p->startTime);
+    db->xProfile(db->pProfileArg, p->zSql, (iNow - p->startTime)*1000000);
   }
 #endif
 
@@ -56841,6 +58569,12 @@
 /*
 ** Extract the user data from a sqlite3_context structure and return a
 ** pointer to it.
+**
+** IMPLEMENTATION-OF: R-46798-50301 The sqlite3_context_db_handle() interface
+** returns a copy of the pointer to the database connection (the 1st
+** parameter) of the sqlite3_create_function() and
+** sqlite3_create_function16() routines that originally registered the
+** application defined function.
 */
 SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context *p){
   assert( p && p->pFunc );
@@ -57050,8 +58784,7 @@
 **     sqlite3_column_real()
 **     sqlite3_column_bytes()
 **     sqlite3_column_bytes16()
-**
-** But not for sqlite3_column_blob(), which never calls malloc().
+**     sqiite3_column_blob()
 */
 static void columnMallocFailure(sqlite3_stmt *pStmt)
 {
@@ -57319,6 +59052,12 @@
 
   /* If the bit corresponding to this variable in Vdbe.expmask is set, then 
   ** binding a new value to this variable invalidates the current query plan.
+  **
+  ** IMPLEMENTATION-OF: R-48440-37595 If the specific value bound to host
+  ** parameter in the WHERE clause might influence the choice of query plan
+  ** for a statement, then the statement will be automatically recompiled,
+  ** as if there had been a schema change, on the first sqlite3_step() call
+  ** following any change to the bindings of that parameter.
   */
   if( p->isPrepareV2 &&
      ((i<32 && p->expmask & ((u32)1 << i)) || p->expmask==0xffffffff)
@@ -57817,6 +59556,17 @@
 */
 
 /*
+** Invoke this macro on memory cells just prior to changing the
+** value of the cell.  This macro verifies that shallow copies are
+** not misused.
+*/
+#ifdef SQLITE_DEBUG
+# define memAboutToChange(P,M) sqlite3VdbeMemPrepareToChange(P,M)
+#else
+# define memAboutToChange(P,M)
+#endif
+
+/*
 ** The following global variable is incremented every time a cursor
 ** moves, either by the OP_SeekXX, OP_Next, or OP_Prev opcodes.  The test
 ** procedures use this information to make sure that indices are
@@ -58361,6 +60111,20 @@
 #endif
 
 /*
+** Transfer error message text from an sqlite3_vtab.zErrMsg (text stored
+** in memory obtained from sqlite3_malloc) into a Vdbe.zErrMsg (text stored
+** in memory obtained from sqlite3DbMalloc).
+*/
+static void importVtabErrMsg(Vdbe *p, sqlite3_vtab *pVtab){
+  sqlite3 *db = p->db;
+  sqlite3DbFree(db, p->zErrMsg);
+  p->zErrMsg = sqlite3DbStrDup(db, pVtab->zErrMsg);
+  sqlite3_free(pVtab->zErrMsg);
+  pVtab->zErrMsg = 0;
+}
+
+
+/*
 ** Execute as much of a VDBE program as we can then return.
 **
 ** sqlite3VdbeMakeReady() must be called before this routine in order to
@@ -58911,6 +60675,7 @@
       assert( pOp->p2>0 );
       assert( pOp->p2<=p->nMem );
       pOut = &aMem[pOp->p2];
+      memAboutToChange(p, pOut);
       sqlite3VdbeMemReleaseExternal(pOut);
       pOut->flags = MEM_Int;
     }
@@ -58920,25 +60685,30 @@
     if( (pOp->opflags & OPFLG_IN1)!=0 ){
       assert( pOp->p1>0 );
       assert( pOp->p1<=p->nMem );
+      assert( memIsValid(&aMem[pOp->p1]) );
       REGISTER_TRACE(pOp->p1, &aMem[pOp->p1]);
     }
     if( (pOp->opflags & OPFLG_IN2)!=0 ){
       assert( pOp->p2>0 );
       assert( pOp->p2<=p->nMem );
+      assert( memIsValid(&aMem[pOp->p2]) );
       REGISTER_TRACE(pOp->p2, &aMem[pOp->p2]);
     }
     if( (pOp->opflags & OPFLG_IN3)!=0 ){
       assert( pOp->p3>0 );
       assert( pOp->p3<=p->nMem );
+      assert( memIsValid(&aMem[pOp->p3]) );
       REGISTER_TRACE(pOp->p3, &aMem[pOp->p3]);
     }
     if( (pOp->opflags & OPFLG_OUT2)!=0 ){
       assert( pOp->p2>0 );
       assert( pOp->p2<=p->nMem );
+      memAboutToChange(p, &aMem[pOp->p2]);
     }
     if( (pOp->opflags & OPFLG_OUT3)!=0 ){
       assert( pOp->p3>0 );
       assert( pOp->p3<=p->nMem );
+      memAboutToChange(p, &aMem[pOp->p3]);
     }
 #endif
   
@@ -59000,6 +60770,7 @@
 case OP_Gosub: {            /* jump, in1 */
   pIn1 = &aMem[pOp->p1];
   assert( (pIn1->flags & MEM_Dyn)==0 );
+  memAboutToChange(p, pIn1);
   pIn1->flags = MEM_Int;
   pIn1->u.i = pc;
   REGISTER_TRACE(pOp->p1, pIn1);
@@ -59207,11 +60978,7 @@
 /* Opcode: Blob P1 P2 * P4
 **
 ** P4 points to a blob of data P1 bytes long.  Store this
-** blob in register P2. This instruction is not coded directly
-** by the compiler. Instead, the compiler layer specifies
-** an OP_HexBlob opcode, with the hex string representation of
-** the blob as P4. This opcode is transformed to an OP_Blob
-** the first time it is executed.
+** blob in register P2.
 */
 case OP_Blob: {                /* out2-prerelease */
   assert( pOp->p1 <= SQLITE_MAX_LENGTH );
@@ -59269,6 +61036,8 @@
   while( u.ac.n-- ){
     assert( pOut<=&aMem[p->nMem] );
     assert( pIn1<=&aMem[p->nMem] );
+    assert( memIsValid(pIn1) );
+    memAboutToChange(p, pOut);
     u.ac.zMalloc = pOut->zMalloc;
     pOut->zMalloc = 0;
     sqlite3VdbeMemMove(pOut, pIn1);
@@ -59314,6 +61083,9 @@
   pOut = &aMem[pOp->p2];
   assert( pOut!=pIn1 );
   sqlite3VdbeMemShallowCopy(pOut, pIn1, MEM_Ephem);
+#ifdef SQLITE_DEBUG
+  if( pOut->pScopyFrom==0 ) pOut->pScopyFrom = pIn1;
+#endif
   REGISTER_TRACE(pOp->p2, pOut);
   break;
 }
@@ -59374,6 +61146,10 @@
   */
   u.ad.pMem = p->pResultSet = &aMem[pOp->p1];
   for(u.ad.i=0; u.ad.i<pOp->p2; u.ad.i++){
+    assert( memIsValid(&u.ad.pMem[u.ad.i]) );
+    Deephemeralize(&u.ad.pMem[u.ad.i]);
+    assert( (u.ad.pMem[u.ad.i].flags & MEM_Ephem)==0
+            || (u.ad.pMem[u.ad.i].flags & (MEM_Str|MEM_Blob))==0 );
     sqlite3VdbeMemNulTerminate(&u.ad.pMem[u.ad.i]);
     sqlite3VdbeMemStoreType(&u.ad.pMem[u.ad.i]);
     REGISTER_TRACE(pOp->p1+u.ad.i, &u.ad.pMem[u.ad.i]);
@@ -59605,12 +61381,17 @@
   u.ag.n = pOp->p5;
   u.ag.apVal = p->apArg;
   assert( u.ag.apVal || u.ag.n==0 );
+  assert( pOp->p3>0 && pOp->p3<=p->nMem );
+  pOut = &aMem[pOp->p3];
+  memAboutToChange(p, pOut);
 
   assert( u.ag.n==0 || (pOp->p2>0 && pOp->p2+u.ag.n<=p->nMem+1) );
   assert( pOp->p3<pOp->p2 || pOp->p3>=pOp->p2+u.ag.n );
   u.ag.pArg = &aMem[pOp->p2];
   for(u.ag.i=0; u.ag.i<u.ag.n; u.ag.i++, u.ag.pArg++){
+    assert( memIsValid(u.ag.pArg) );
     u.ag.apVal[u.ag.i] = u.ag.pArg;
+    Deephemeralize(u.ag.pArg);
     sqlite3VdbeMemStoreType(u.ag.pArg);
     REGISTER_TRACE(pOp->p2+u.ag.i, u.ag.pArg);
   }
@@ -59624,8 +61405,6 @@
     u.ag.ctx.pFunc = u.ag.ctx.pVdbeFunc->pFunc;
   }
 
-  assert( pOp->p3>0 && pOp->p3<=p->nMem );
-  pOut = &aMem[pOp->p3];
   u.ag.ctx.s.flags = MEM_Null;
   u.ag.ctx.s.db = db;
   u.ag.ctx.s.xDel = 0;
@@ -59645,7 +61424,7 @@
     assert( pOp[-1].opcode==OP_CollSeq );
     u.ag.ctx.pColl = pOp[-1].p4.pColl;
   }
-  (*u.ag.ctx.pFunc->xFunc)(&u.ag.ctx, u.ag.n, u.ag.apVal);
+  (*u.ag.ctx.pFunc->xFunc)(&u.ag.ctx, u.ag.n, u.ag.apVal); /* IMP: R-24505-23230 */
   if( db->mallocFailed ){
     /* Even though a malloc() has failed, the implementation of the
     ** user function may have called an sqlite3_result_XXX() function
@@ -59697,7 +61476,7 @@
 /* Opcode: ShiftLeft P1 P2 P3 * *
 **
 ** Shift the integer value in register P2 to the left by the
-** number of bits specified by the integer in regiser P1.
+** number of bits specified by the integer in register P1.
 ** Store the result in register P3.
 ** If either input is NULL, the result is NULL.
 */
@@ -59747,6 +61526,7 @@
 */
 case OP_AddImm: {            /* in1 */
   pIn1 = &aMem[pOp->p1];
+  memAboutToChange(p, pIn1);
   sqlite3VdbeMemIntegerify(pIn1);
   pIn1->u.i += pOp->p2;
   break;
@@ -59761,6 +61541,7 @@
 */
 case OP_MustBeInt: {            /* jump, in1 */
   pIn1 = &aMem[pOp->p1];
+  memAboutToChange(p, pIn1);
   applyAffinity(pIn1, SQLITE_AFF_NUMERIC, encoding);
   if( (pIn1->flags & MEM_Int)==0 ){
     if( pOp->p2==0 ){
@@ -59787,6 +61568,7 @@
 */
 case OP_RealAffinity: {                  /* in1 */
   pIn1 = &aMem[pOp->p1];
+  memAboutToChange(p, pIn1);
   if( pIn1->flags & MEM_Int ){
     sqlite3VdbeMemRealify(pIn1);
   }
@@ -59806,6 +61588,7 @@
 */
 case OP_ToText: {                  /* same as TK_TO_TEXT, in1 */
   pIn1 = &aMem[pOp->p1];
+  memAboutToChange(p, pIn1);
   if( pIn1->flags & MEM_Null ) break;
   assert( MEM_Str==(MEM_Blob>>3) );
   pIn1->flags |= (pIn1->flags&MEM_Blob)>>3;
@@ -59828,6 +61611,7 @@
 */
 case OP_ToBlob: {                  /* same as TK_TO_BLOB, in1 */
   pIn1 = &aMem[pOp->p1];
+  memAboutToChange(p, pIn1);
   if( pIn1->flags & MEM_Null ) break;
   if( (pIn1->flags & MEM_Blob)==0 ){
     applyAffinity(pIn1, SQLITE_AFF_TEXT, encoding);
@@ -59852,6 +61636,7 @@
 */
 case OP_ToNumeric: {                  /* same as TK_TO_NUMERIC, in1 */
   pIn1 = &aMem[pOp->p1];
+  memAboutToChange(p, pIn1);
   if( (pIn1->flags & (MEM_Null|MEM_Int|MEM_Real))==0 ){
     sqlite3VdbeMemNumerify(pIn1);
   }
@@ -59861,7 +61646,7 @@
 
 /* Opcode: ToInt P1 * * * *
 **
-** Force the value in register P1 be an integer.  If
+** Force the value in register P1 to be an integer.  If
 ** The value is currently a real number, drop its fractional part.
 ** If the value is text or blob, try to convert it to an integer using the
 ** equivalent of atoi() and store 0 if no such conversion is possible.
@@ -59870,6 +61655,7 @@
 */
 case OP_ToInt: {                  /* same as TK_TO_INT, in1 */
   pIn1 = &aMem[pOp->p1];
+  memAboutToChange(p, pIn1);
   if( (pIn1->flags & MEM_Null)==0 ){
     sqlite3VdbeMemIntegerify(pIn1);
   }
@@ -59888,6 +61674,7 @@
 */
 case OP_ToReal: {                  /* same as TK_TO_REAL, in1 */
   pIn1 = &aMem[pOp->p1];
+  memAboutToChange(p, pIn1);
   if( (pIn1->flags & MEM_Null)==0 ){
     sqlite3VdbeMemRealify(pIn1);
   }
@@ -59902,7 +61689,7 @@
 **
 ** If the SQLITE_JUMPIFNULL bit of P5 is set and either reg(P1) or
 ** reg(P3) is NULL then take the jump.  If the SQLITE_JUMPIFNULL 
-** bit is clear then fall thru if either operand is NULL.
+** bit is clear then fall through if either operand is NULL.
 **
 ** The SQLITE_AFF_MASK portion of P5 must be an affinity character -
 ** SQLITE_AFF_TEXT, SQLITE_AFF_INTEGER, and so forth. An attempt is made 
@@ -59982,6 +61769,8 @@
 
   pIn1 = &aMem[pOp->p1];
   pIn3 = &aMem[pOp->p3];
+  memAboutToChange(p, pIn1);
+  memAboutToChange(p, pIn3);
   u.ai.flags1 = pIn1->flags;
   u.ai.flags3 = pIn3->flags;
   if( (pIn1->flags | pIn3->flags)&MEM_Null ){
@@ -60032,6 +61821,7 @@
 
   if( pOp->p5 & SQLITE_STOREP2 ){
     pOut = &aMem[pOp->p2];
+    memAboutToChange(p, pOut);
     MemSetTypeFlag(pOut, MEM_Int);
     pOut->u.i = u.ai.res;
     REGISTER_TRACE(pOp->p2, pOut);
@@ -60063,8 +61853,8 @@
 
 /* Opcode: Compare P1 P2 P3 P4 *
 **
-** Compare to vectors of registers in reg(P1)..reg(P1+P3-1) (all this
-** one "A") and in reg(P2)..reg(P2+P3-1) ("B").  Save the result of
+** Compare two vectors of registers in reg(P1)..reg(P1+P3-1) (call this
+** vector "A") and in reg(P2)..reg(P2+P3-1) ("B").  Save the result of
 ** the comparison for use by the next OP_Jump instruct.
 **
 ** P4 is a KeyInfo structure that defines collating sequences and sort
@@ -60106,6 +61896,8 @@
 #endif /* SQLITE_DEBUG */
   for(u.aj.i=0; u.aj.i<u.aj.n; u.aj.i++){
     u.aj.idx = aPermute ? aPermute[u.aj.i] : u.aj.i;
+    assert( memIsValid(&aMem[u.aj.p1+u.aj.idx]) );
+    assert( memIsValid(&aMem[u.aj.p2+u.aj.idx]) );
     REGISTER_TRACE(u.aj.p1+u.aj.idx, &aMem[u.aj.p1+u.aj.idx]);
     REGISTER_TRACE(u.aj.p2+u.aj.idx, &aMem[u.aj.p2+u.aj.idx]);
     assert( u.aj.i<u.aj.pKeyInfo->nField );
@@ -60337,6 +62129,7 @@
   assert( u.am.p1<p->nCursor );
   assert( pOp->p3>0 && pOp->p3<=p->nMem );
   u.am.pDest = &aMem[pOp->p3];
+  memAboutToChange(p, u.am.pDest);
   MemSetTypeFlag(u.am.pDest, MEM_Null);
   u.am.zRec = 0;
 
@@ -60384,6 +62177,7 @@
   }else if( u.am.pC->pseudoTableReg>0 ){
     u.am.pReg = &aMem[u.am.pC->pseudoTableReg];
     assert( u.am.pReg->flags & MEM_Blob );
+    assert( memIsValid(u.am.pReg) );
     u.am.payloadSize = u.am.pReg->n;
     u.am.zRec = u.am.pReg->z;
     u.am.pC->cacheStatus = (pOp->p5&OPFLAG_CLEARCACHE) ? CACHE_STALE : p->cacheCtr;
@@ -60608,6 +62402,8 @@
   pIn1 = &aMem[pOp->p1];
   while( (u.an.cAff = *(u.an.zAffinity++))!=0 ){
     assert( pIn1 <= &p->aMem[p->nMem] );
+    assert( memIsValid(pIn1) );
+    memAboutToChange(p, pIn1);
     ExpandBlob(pIn1);
     applyAffinity(pIn1, u.an.cAff, encoding);
     pIn1++;
@@ -60617,12 +62413,9 @@
 
 /* Opcode: MakeRecord P1 P2 P3 P4 *
 **
-** Convert P2 registers beginning with P1 into a single entry
-** suitable for use as a data record in a database table or as a key
-** in an index.  The details of the format are irrelevant as long as
-** the OP_Column opcode can decode the record later.
-** Refer to source code comments for the details of the record
-** format.
+** Convert P2 registers beginning with P1 into the [record format]
+** use as a data record in a database table or as a key
+** in an index.  The OP_Column opcode can decode the record later.
 **
 ** P4 may be a string that is P2 characters long.  The nth character of the
 ** string indicates the column affinity that should be used for the nth
@@ -60679,11 +62472,18 @@
   u.ao.pLast = &u.ao.pData0[u.ao.nField-1];
   u.ao.file_format = p->minWriteFileFormat;
 
+  /* Identify the output register */
+  assert( pOp->p3<pOp->p1 || pOp->p3>=pOp->p1+pOp->p2 );
+  pOut = &aMem[pOp->p3];
+  memAboutToChange(p, pOut);
+
   /* Loop through the elements that will make up the record to figure
   ** out how much space is required for the new record.
   */
   for(u.ao.pRec=u.ao.pData0; u.ao.pRec<=u.ao.pLast; u.ao.pRec++){
+    assert( memIsValid(u.ao.pRec) );
     if( u.ao.zAffinity ){
+      memAboutToChange(p, u.ao.pRec);
       applyAffinity(u.ao.pRec, u.ao.zAffinity[u.ao.pRec-u.ao.pData0], encoding);
     }
     if( u.ao.pRec->flags&MEM_Zero && u.ao.pRec->n>0 ){
@@ -60717,8 +62517,6 @@
   ** be one of the input registers (because the following call to
   ** sqlite3VdbeMemGrow() could clobber the value before it is used).
   */
-  assert( pOp->p3<pOp->p1 || pOp->p3>=pOp->p1+pOp->p2 );
-  pOut = &aMem[pOp->p3];
   if( sqlite3VdbeMemGrow(pOut, (int)u.ao.nByte, 0) ){
     goto no_mem;
   }
@@ -60891,6 +62689,7 @@
         if( u.aq.p1==SAVEPOINT_ROLLBACK && (db->flags&SQLITE_InternChanges)!=0 ){
           sqlite3ExpirePreparedStatements(db);
           sqlite3ResetInternalSchema(db, 0);
+          db->flags = (db->flags | SQLITE_InternChanges);
         }
       }
 
@@ -61281,6 +63080,8 @@
     assert( u.aw.p2>0 );
     assert( u.aw.p2<=p->nMem );
     pIn2 = &aMem[u.aw.p2];
+    assert( memIsValid(pIn2) );
+    assert( (pIn2->flags & MEM_Int)!=0 );
     sqlite3VdbeMemIntegerify(pIn2);
     u.aw.p2 = (int)pIn2->u.i;
     /* The u.aw.p2 value always comes from a prior OP_CreateTable opcode and
@@ -61303,6 +63104,7 @@
   u.aw.pCur = allocateCursor(p, pOp->p1, u.aw.nField, u.aw.iDb, 1);
   if( u.aw.pCur==0 ) goto no_mem;
   u.aw.pCur->nullRow = 1;
+  u.aw.pCur->isOrdered = 1;
   rc = sqlite3BtreeCursor(u.aw.pX, u.aw.p2, u.aw.wrFlag, u.aw.pKeyInfo, u.aw.pCur->pCursor);
   u.aw.pCur->pKeyInfo = u.aw.pKeyInfo;
 
@@ -61355,7 +63157,7 @@
 #if 0  /* local variables moved into u.ax */
   VdbeCursor *pCx;
 #endif /* local variables moved into u.ax */
-  static const int openFlags =
+  static const int vfsFlags =
       SQLITE_OPEN_READWRITE |
       SQLITE_OPEN_CREATE |
       SQLITE_OPEN_EXCLUSIVE |
@@ -61366,21 +63168,21 @@
   u.ax.pCx = allocateCursor(p, pOp->p1, pOp->p2, -1, 1);
   if( u.ax.pCx==0 ) goto no_mem;
   u.ax.pCx->nullRow = 1;
-  rc = sqlite3BtreeFactory(db, 0, 1, SQLITE_DEFAULT_TEMP_CACHE_SIZE, openFlags,
-                           &u.ax.pCx->pBt);
+  rc = sqlite3BtreeOpen(0, db, &u.ax.pCx->pBt,
+                        BTREE_OMIT_JOURNAL | BTREE_SINGLE | pOp->p5, vfsFlags);
   if( rc==SQLITE_OK ){
     rc = sqlite3BtreeBeginTrans(u.ax.pCx->pBt, 1);
   }
   if( rc==SQLITE_OK ){
     /* If a transient index is required, create it by calling
-    ** sqlite3BtreeCreateTable() with the BTREE_ZERODATA flag before
+    ** sqlite3BtreeCreateTable() with the BTREE_BLOBKEY flag before
     ** opening it. If a transient table is required, just use the
-    ** automatically created table with root-page 1 (an INTKEY table).
+    ** automatically created table with root-page 1 (an BLOB_INTKEY table).
     */
     if( pOp->p4.pKeyInfo ){
       int pgno;
       assert( pOp->p4type==P4_KEYINFO );
-      rc = sqlite3BtreeCreateTable(u.ax.pCx->pBt, &pgno, BTREE_ZERODATA);
+      rc = sqlite3BtreeCreateTable(u.ax.pCx->pBt, &pgno, BTREE_BLOBKEY);
       if( rc==SQLITE_OK ){
         assert( pgno==MASTER_ROOT+1 );
         rc = sqlite3BtreeCursor(u.ax.pCx->pBt, pgno, 1,
@@ -61394,6 +63196,7 @@
       u.ax.pCx->isTable = 1;
     }
   }
+  u.ax.pCx->isOrdered = (pOp->p5!=BTREE_UNORDERED);
   u.ax.pCx->isIndex = !u.ax.pCx->isTable;
   break;
 }
@@ -61513,6 +63316,7 @@
   assert( OP_SeekLe == OP_SeekLt+1 );
   assert( OP_SeekGe == OP_SeekLt+2 );
   assert( OP_SeekGt == OP_SeekLt+3 );
+  assert( u.az.pC->isOrdered );
   if( u.az.pC->pCursor!=0 ){
     u.az.oc = pOp->opcode;
     u.az.pC->nullRow = 0;
@@ -61595,6 +63399,9 @@
       assert( u.az.oc!=OP_SeekLt || u.az.r.flags==0 );
 
       u.az.r.aMem = &aMem[pOp->p3];
+#ifdef SQLITE_DEBUG
+      { int i; for(i=0; i<u.az.r.nField; i++) assert( memIsValid(&u.az.r.aMem[i]) ); }
+#endif
       ExpandBlob(u.az.r.aMem);
       rc = sqlite3BtreeMovetoUnpacked(u.az.pC->pCursor, &u.az.r, 0, 0, &u.az.res);
       if( rc!=SQLITE_OK ){
@@ -61723,11 +63530,14 @@
       u.bb.r.pKeyInfo = u.bb.pC->pKeyInfo;
       u.bb.r.nField = (u16)pOp->p4.i;
       u.bb.r.aMem = pIn3;
+#ifdef SQLITE_DEBUG
+      { int i; for(i=0; i<u.bb.r.nField; i++) assert( memIsValid(&u.bb.r.aMem[i]) ); }
+#endif
       u.bb.r.flags = UNPACKED_PREFIX_MATCH;
       u.bb.pIdxKey = &u.bb.r;
     }else{
       assert( pIn3->flags & MEM_Blob );
-      ExpandBlob(pIn3);
+      assert( (pIn3->flags & MEM_Zero)==0 );  /* zeroblobs already expanded */
       u.bb.pIdxKey = sqlite3VdbeRecordUnpack(u.bb.pC->pKeyInfo, pIn3->n, pIn3->z,
                                         u.bb.aTempRec, sizeof(u.bb.aTempRec));
       if( u.bb.pIdxKey==0 ){
@@ -61822,6 +63632,9 @@
     u.bc.r.nField = u.bc.nField + 1;
     u.bc.r.flags = UNPACKED_PREFIX_SEARCH;
     u.bc.r.aMem = u.bc.aMx;
+#ifdef SQLITE_DEBUG
+    { int i; for(i=0; i<u.bc.r.nField; i++) assert( memIsValid(&u.bc.r.aMem[i]) ); }
+#endif
 
     /* Extract the value of u.bc.R from register P3. */
     sqlite3VdbeMemIntegerify(pIn3);
@@ -61844,7 +63657,7 @@
 **
 ** Use the content of register P3 as a integer key.  If a record 
 ** with that key does not exist in table of P1, then jump to P2. 
-** If the record does exist, then fall thru.  The cursor is left 
+** If the record does exist, then fall through.  The cursor is left 
 ** pointing to the record if it exists.
 **
 ** The difference between this operation and NotFound is that this
@@ -62002,7 +63815,9 @@
           /* Assert that P3 is a valid memory cell. */
           assert( pOp->p3<=p->nMem );
           u.be.pMem = &aMem[pOp->p3];
+          memAboutToChange(p, u.be.pMem);
         }
+        assert( memIsValid(u.be.pMem) );
 
         REGISTER_TRACE(pOp->p3, u.be.pMem);
         sqlite3VdbeMemIntegerify(u.be.pMem);
@@ -62021,29 +63836,36 @@
       sqlite3BtreeSetCachedRowid(u.be.pC->pCursor, u.be.v<MAX_ROWID ? u.be.v+1 : 0);
     }
     if( u.be.pC->useRandomRowid ){
-      /* IMPLEMENTATION-OF: R-48598-02938 If the largest ROWID is equal to the
+      /* IMPLEMENTATION-OF: R-07677-41881 If the largest ROWID is equal to the
       ** largest possible integer (9223372036854775807) then the database
-      ** engine starts picking candidate ROWIDs at random until it finds one
-      ** that is not previously used.
-      */
+      ** engine starts picking positive candidate ROWIDs at random until
+      ** it finds one that is not previously used. */
       assert( pOp->p3==0 );  /* We cannot be in random rowid mode if this is
                              ** an AUTOINCREMENT table. */
+      /* on the first attempt, simply do one more than previous */
       u.be.v = db->lastRowid;
+      u.be.v &= (MAX_ROWID>>1); /* ensure doesn't go negative */
+      u.be.v++; /* ensure non-zero */
       u.be.cnt = 0;
-      do{
-        if( u.be.cnt==0 && (u.be.v&0xffffff)==u.be.v ){
-          u.be.v++;
+      while(   ((rc = sqlite3BtreeMovetoUnpacked(u.be.pC->pCursor, 0, (u64)u.be.v,
+                                                 0, &u.be.res))==SQLITE_OK)
+            && (u.be.res==0)
+            && (++u.be.cnt<100)){
+        /* collision - try another random rowid */
+        sqlite3_randomness(sizeof(u.be.v), &u.be.v);
+        if( u.be.cnt<5 ){
+          /* try "small" random rowids for the initial attempts */
+          u.be.v &= 0xffffff;
         }else{
-          sqlite3_randomness(sizeof(u.be.v), &u.be.v);
-          if( u.be.cnt<5 ) u.be.v &= 0xffffff;
+          u.be.v &= (MAX_ROWID>>1); /* ensure doesn't go negative */
         }
-        rc = sqlite3BtreeMovetoUnpacked(u.be.pC->pCursor, 0, (u64)u.be.v, 0, &u.be.res);
-        u.be.cnt++;
-      }while( u.be.cnt<100 && rc==SQLITE_OK && u.be.res==0 );
+        u.be.v++; /* ensure non-zero */
+      }
       if( rc==SQLITE_OK && u.be.res==0 ){
         rc = SQLITE_FULL;   /* IMP: R-38219-53002 */
         goto abort_due_to_error;
       }
+      assert( u.be.v>0 );  /* EV: R-40812-03570 */
     }
     u.be.pC->rowidIsValid = 0;
     u.be.pC->deferredMoveto = 0;
@@ -62113,6 +63935,7 @@
 
   u.bf.pData = &aMem[pOp->p2];
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
+  assert( memIsValid(u.bf.pData) );
   u.bf.pC = p->apCsr[pOp->p1];
   assert( u.bf.pC!=0 );
   assert( u.bf.pC->pCursor!=0 );
@@ -62123,6 +63946,7 @@
   if( pOp->opcode==OP_Insert ){
     u.bf.pKey = &aMem[pOp->p3];
     assert( u.bf.pKey->flags & MEM_Int );
+    assert( memIsValid(u.bf.pKey) );
     REGISTER_TRACE(pOp->p3, u.bf.pKey);
     u.bf.iKey = u.bf.pKey->u.i;
   }else{
@@ -62274,6 +64098,7 @@
 #endif /* local variables moved into u.bh */
 
   pOut = &aMem[pOp->p2];
+  memAboutToChange(p, pOut);
 
   /* Note that RowKey and RowData are really exactly the same instruction */
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
@@ -62358,9 +64183,7 @@
     u.bi.pModule = u.bi.pVtab->pModule;
     assert( u.bi.pModule->xRowid );
     rc = u.bi.pModule->xRowid(u.bi.pC->pVtabCursor, &u.bi.v);
-    sqlite3DbFree(db, p->zErrMsg);
-    p->zErrMsg = u.bi.pVtab->zErrMsg;
-    u.bi.pVtab->zErrMsg = 0;
+    importVtabErrMsg(p, u.bi.pVtab);
 #endif /* SQLITE_OMIT_VIRTUALTABLE */
   }else{
     assert( u.bi.pC->pCursor!=0 );
@@ -62618,6 +64441,9 @@
     u.bo.r.nField = (u16)pOp->p3;
     u.bo.r.flags = 0;
     u.bo.r.aMem = &aMem[pOp->p2];
+#ifdef SQLITE_DEBUG
+    { int i; for(i=0; i<u.bo.r.nField; i++) assert( memIsValid(&u.bo.r.aMem[i]) ); }
+#endif
     rc = sqlite3BtreeMovetoUnpacked(u.bo.pCrsr, &u.bo.r, 0, 0, &u.bo.res);
     if( rc==SQLITE_OK && u.bo.res==0 ){
       rc = sqlite3BtreeDelete(u.bo.pCrsr);
@@ -62679,7 +64505,7 @@
 ** that if the key from register P3 is a prefix of the key in the cursor,
 ** the result is false whereas it would be true with IdxGT.
 */
-/* Opcode: IdxLT P1 P2 P3 * P5
+/* Opcode: IdxLT P1 P2 P3 P4 P5
 **
 ** The P4 register values beginning with P3 form an unpacked index 
 ** key that omits the ROWID.  Compare this key value against the index 
@@ -62702,6 +64528,7 @@
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
   u.bq.pC = p->apCsr[pOp->p1];
   assert( u.bq.pC!=0 );
+  assert( u.bq.pC->isOrdered );
   if( ALWAYS(u.bq.pC->pCursor!=0) ){
     assert( u.bq.pC->deferredMoveto==0 );
     assert( pOp->p5==0 || pOp->p5==1 );
@@ -62714,6 +64541,9 @@
       u.bq.r.flags = UNPACKED_IGNORE_ROWID;
     }
     u.bq.r.aMem = &aMem[pOp->p3];
+#ifdef SQLITE_DEBUG
+    { int i; for(i=0; i<u.bq.r.nField; i++) assert( memIsValid(&u.bq.r.aMem[i]) ); }
+#endif
     rc = sqlite3VdbeIdxKeyCompare(u.bq.pC, &u.bq.r, &u.bq.res);
     if( pOp->opcode==OP_IdxLT ){
       u.bq.res = -u.bq.res;
@@ -62817,6 +64647,8 @@
   if( pOp->p3 ){
     p->nChange += u.bs.nChange;
     if( pOp->p3>0 ){
+      assert( memIsValid(&aMem[pOp->p3]) );
+      memAboutToChange(p, &aMem[pOp->p3]);
       aMem[pOp->p3].u.i += u.bs.nChange;
     }
   }
@@ -62860,9 +64692,9 @@
   assert( u.bt.pDb->pBt!=0 );
   if( pOp->opcode==OP_CreateTable ){
     /* u.bt.flags = BTREE_INTKEY; */
-    u.bt.flags = BTREE_LEAFDATA|BTREE_INTKEY;
+    u.bt.flags = BTREE_INTKEY;
   }else{
-    u.bt.flags = BTREE_ZERODATA;
+    u.bt.flags = BTREE_BLOBKEY;
   }
   rc = sqlite3BtreeCreateTable(u.bt.pDb->pBt, &u.bt.pgno, u.bt.flags);
   pOut->u.i = u.bt.pgno;
@@ -63191,6 +65023,7 @@
 
   u.by.pProgram = pOp->p4.pProgram;
   u.by.pRt = &aMem[pOp->p3];
+  assert( memIsValid(u.by.pRt) );
   assert( u.by.pProgram->nOp>0 );
 
   /* If the p5 flag is clear, then recursive invocation of triggers is
@@ -63364,6 +65197,7 @@
   }else{
     u.ca.pIn1 = &aMem[pOp->p1];
   }
+  assert( memIsValid(u.ca.pIn1) );
   sqlite3VdbeMemIntegerify(u.ca.pIn1);
   pIn2 = &aMem[pOp->p2];
   sqlite3VdbeMemIntegerify(pIn2);
@@ -63450,7 +65284,9 @@
   u.cb.apVal = p->apArg;
   assert( u.cb.apVal || u.cb.n==0 );
   for(u.cb.i=0; u.cb.i<u.cb.n; u.cb.i++, u.cb.pRec++){
+    assert( memIsValid(u.cb.pRec) );
     u.cb.apVal[u.cb.i] = u.cb.pRec;
+    memAboutToChange(p, u.cb.pRec);
     sqlite3VdbeMemStoreType(u.cb.pRec);
   }
   u.cb.ctx.pFunc = pOp->p4.pFunc;
@@ -63470,7 +65306,7 @@
     assert( pOp[-1].opcode==OP_CollSeq );
     u.cb.ctx.pColl = pOp[-1].p4.pColl;
   }
-  (u.cb.ctx.pFunc->xStep)(&u.cb.ctx, u.cb.n, u.cb.apVal);
+  (u.cb.ctx.pFunc->xStep)(&u.cb.ctx, u.cb.n, u.cb.apVal); /* IMP: R-24505-23230 */
   if( u.cb.ctx.isError ){
     sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3_value_text(&u.cb.ctx.s));
     rc = u.cb.ctx.isError;
@@ -63533,11 +65369,6 @@
 ** If changing into or out of WAL mode the procedure is more complicated.
 **
 ** Write a string containing the final journal-mode to register P2.
-**
-** If an attempt to change in to or out of WAL mode fails because another
-** connection also has the same database open, then an SQLITE_BUSY error
-** is raised if P5==0, or of P5!=0 the journal mode changed is skipped
-** without signaling the error.
 */
 case OP_JournalMode: {    /* out2-prerelease */
 #if 0  /* local variables moved into u.cd */
@@ -63588,11 +65419,11 @@
   u.cd.zFilename = sqlite3PagerFilename(u.cd.pPager);
 
   /* Do not allow a transition to journal_mode=WAL for a database
-  ** in temporary storage or if the VFS does not support xShmOpen.
+  ** in temporary storage or if the VFS does not support shared memory
   */
   if( u.cd.eNew==PAGER_JOURNALMODE_WAL
    && (u.cd.zFilename[0]==0                         /* Temp file */
-       || !sqlite3PagerWalSupported(u.cd.pPager))   /* No xShmOpen support */
+       || !sqlite3PagerWalSupported(u.cd.pPager))   /* No shared-memory support */
   ){
     u.cd.eNew = u.cd.eOld;
   }
@@ -63637,7 +65468,6 @@
 #endif /* ifndef SQLITE_OMIT_WAL */
 
   if( rc ){
-    if( rc==SQLITE_BUSY && pOp->p5!=0 ) rc = SQLITE_OK;
     u.cd.eNew = u.cd.eOld;
   }
   u.cd.eNew = sqlite3PagerSetJournalMode(u.cd.pPager, u.cd.eNew);
@@ -63755,11 +65585,7 @@
 #endif /* local variables moved into u.cf */
   u.cf.pVTab = pOp->p4.pVtab;
   rc = sqlite3VtabBegin(db, u.cf.pVTab);
-  if( u.cf.pVTab ){
-    sqlite3DbFree(db, p->zErrMsg);
-    p->zErrMsg = u.cf.pVTab->pVtab->zErrMsg;
-    u.cf.pVTab->pVtab->zErrMsg = 0;
-  }
+  if( u.cf.pVTab ) importVtabErrMsg(p, u.cf.pVTab->pVtab);
   break;
 }
 #endif /* SQLITE_OMIT_VIRTUALTABLE */
@@ -63811,9 +65637,7 @@
   u.cg.pModule = (sqlite3_module *)u.cg.pVtab->pModule;
   assert(u.cg.pVtab && u.cg.pModule);
   rc = u.cg.pModule->xOpen(u.cg.pVtab, &u.cg.pVtabCursor);
-  sqlite3DbFree(db, p->zErrMsg);
-  p->zErrMsg = u.cg.pVtab->zErrMsg;
-  u.cg.pVtab->zErrMsg = 0;
+  importVtabErrMsg(p, u.cg.pVtab);
   if( SQLITE_OK==rc ){
     /* Initialize sqlite3_vtab_cursor base class */
     u.cg.pVtabCursor->pVtab = u.cg.pVtab;
@@ -63869,6 +65693,7 @@
   u.ch.pQuery = &aMem[pOp->p3];
   u.ch.pArgc = &u.ch.pQuery[1];
   u.ch.pCur = p->apCsr[pOp->p1];
+  assert( memIsValid(u.ch.pQuery) );
   REGISTER_TRACE(pOp->p3, u.ch.pQuery);
   assert( u.ch.pCur->pVtabCursor );
   u.ch.pVtabCursor = u.ch.pCur->pVtabCursor;
@@ -63892,9 +65717,7 @@
     p->inVtabMethod = 1;
     rc = u.ch.pModule->xFilter(u.ch.pVtabCursor, u.ch.iQuery, pOp->p4.z, u.ch.nArg, u.ch.apArg);
     p->inVtabMethod = 0;
-    sqlite3DbFree(db, p->zErrMsg);
-    p->zErrMsg = u.ch.pVtab->zErrMsg;
-    u.ch.pVtab->zErrMsg = 0;
+    importVtabErrMsg(p, u.ch.pVtab);
     if( rc==SQLITE_OK ){
       u.ch.res = u.ch.pModule->xEof(u.ch.pVtabCursor);
     }
@@ -63928,6 +65751,7 @@
   assert( pCur->pVtabCursor );
   assert( pOp->p3>0 && pOp->p3<=p->nMem );
   u.ci.pDest = &aMem[pOp->p3];
+  memAboutToChange(p, u.ci.pDest);
   if( pCur->nullRow ){
     sqlite3VdbeMemSetNull(u.ci.pDest);
     break;
@@ -63946,9 +65770,7 @@
   MemSetTypeFlag(&u.ci.sContext.s, MEM_Null);
 
   rc = u.ci.pModule->xColumn(pCur->pVtabCursor, &u.ci.sContext, pOp->p2);
-  sqlite3DbFree(db, p->zErrMsg);
-  p->zErrMsg = u.ci.pVtab->zErrMsg;
-  u.ci.pVtab->zErrMsg = 0;
+  importVtabErrMsg(p, u.ci.pVtab);
   if( u.ci.sContext.isError ){
     rc = u.ci.sContext.isError;
   }
@@ -64003,9 +65825,7 @@
   p->inVtabMethod = 1;
   rc = u.cj.pModule->xNext(u.cj.pCur->pVtabCursor);
   p->inVtabMethod = 0;
-  sqlite3DbFree(db, p->zErrMsg);
-  p->zErrMsg = u.cj.pVtab->zErrMsg;
-  u.cj.pVtab->zErrMsg = 0;
+  importVtabErrMsg(p, u.cj.pVtab);
   if( rc==SQLITE_OK ){
     u.cj.res = u.cj.pModule->xEof(u.cj.pCur->pVtabCursor);
   }
@@ -64034,12 +65854,12 @@
   u.ck.pVtab = pOp->p4.pVtab->pVtab;
   u.ck.pName = &aMem[pOp->p1];
   assert( u.ck.pVtab->pModule->xRename );
+  assert( memIsValid(u.ck.pName) );
   REGISTER_TRACE(pOp->p1, u.ck.pName);
   assert( u.ck.pName->flags & MEM_Str );
   rc = u.ck.pVtab->pModule->xRename(u.ck.pVtab, u.ck.pName->z);
-  sqlite3DbFree(db, p->zErrMsg);
-  p->zErrMsg = u.ck.pVtab->zErrMsg;
-  u.ck.pVtab->zErrMsg = 0;
+  importVtabErrMsg(p, u.ck.pVtab);
+  p->expired = 0;
 
   break;
 }
@@ -64088,14 +65908,14 @@
     u.cl.apArg = p->apArg;
     u.cl.pX = &aMem[pOp->p3];
     for(u.cl.i=0; u.cl.i<u.cl.nArg; u.cl.i++){
+      assert( memIsValid(u.cl.pX) );
+      memAboutToChange(p, u.cl.pX);
       sqlite3VdbeMemStoreType(u.cl.pX);
       u.cl.apArg[u.cl.i] = u.cl.pX;
       u.cl.pX++;
     }
     rc = u.cl.pModule->xUpdate(u.cl.pVtab, u.cl.nArg, u.cl.apArg, &u.cl.rowid);
-    sqlite3DbFree(db, p->zErrMsg);
-    p->zErrMsg = u.cl.pVtab->zErrMsg;
-    u.cl.pVtab->zErrMsg = 0;
+    importVtabErrMsg(p, u.cl.pVtab);
     if( rc==SQLITE_OK && pOp->p1 ){
       assert( u.cl.nArg>1 && u.cl.apArg[0] && (u.cl.apArg[0]->flags&MEM_Null) );
       db->lastRowid = u.cl.rowid;
@@ -64835,11 +66655,10 @@
   0,             /* xFileControl */
   0,             /* xSectorSize */
   0,             /* xDeviceCharacteristics */
-  0,             /* xShmOpen */
-  0,             /* xShmLock */
   0,             /* xShmMap */
+  0,             /* xShmLock */
   0,             /* xShmBarrier */
-  0              /* xShmClose */
+  0              /* xShmUnmap */
 };
 
 /* 
@@ -65120,11 +66939,10 @@
   0,                /* xFileControl */
   0,                /* xSectorSize */
   0,                /* xDeviceCharacteristics */
-  0,                /* xShmOpen */
-  0,                /* xShmLock */
   0,                /* xShmMap */
+  0,                /* xShmLock */
   0,                /* xShmBarrier */
-  0                 /* xShmClose */
+  0                 /* xShmUnlock */
 };
 
 /* 
@@ -65146,8 +66964,7 @@
 }
 
 /* 
-** Return the number of bytes required to store a MemJournal that uses vfs
-** pVfs to create the underlying on-disk files.
+** Return the number of bytes required to store a MemJournal file descriptor.
 */
 SQLITE_PRIVATE int sqlite3MemJournalSize(void){
   return sizeof(MemJournal);
@@ -66552,24 +68369,31 @@
 }
 
 /*
+** Set the explicit collating sequence for an expression to the
+** collating sequence supplied in the second argument.
+*/
+SQLITE_PRIVATE Expr *sqlite3ExprSetColl(Expr *pExpr, CollSeq *pColl){
+  if( pExpr && pColl ){
+    pExpr->pColl = pColl;
+    pExpr->flags |= EP_ExpCollate;
+  }
+  return pExpr;
+}
+
+/*
 ** Set the collating sequence for expression pExpr to be the collating
 ** sequence named by pToken.   Return a pointer to the revised expression.
 ** The collating sequence is marked as "explicit" using the EP_ExpCollate
 ** flag.  An explicit collating sequence will override implicit
 ** collating sequences.
 */
-SQLITE_PRIVATE Expr *sqlite3ExprSetColl(Parse *pParse, Expr *pExpr, Token *pCollName){
+SQLITE_PRIVATE Expr *sqlite3ExprSetCollByToken(Parse *pParse, Expr *pExpr, Token *pCollName){
   char *zColl = 0;            /* Dequoted name of collation sequence */
   CollSeq *pColl;
   sqlite3 *db = pParse->db;
   zColl = sqlite3NameFromToken(db, pCollName);
-  if( pExpr && zColl ){
-    pColl = sqlite3LocateCollSeq(pParse, zColl);
-    if( pColl ){
-      pExpr->pColl = pColl;
-      pExpr->flags |= EP_ExpCollate;
-    }
-  }
+  pColl = sqlite3LocateCollSeq(pParse, zColl);
+  sqlite3ExprSetColl(pExpr, pColl);
   sqlite3DbFree(db, zColl);
   return pExpr;
 }
@@ -67043,18 +68867,19 @@
   }else if( z[0]=='?' ){
     /* Wildcard of the form "?nnn".  Convert "nnn" to an integer and
     ** use it as the variable number */
-    int i = atoi((char*)&z[1]);
+    i64 i;
+    int bOk = sqlite3Atoi64(&z[1], &i);
     pExpr->iColumn = (ynVar)i;
     testcase( i==0 );
     testcase( i==1 );
     testcase( i==db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER]-1 );
     testcase( i==db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] );
-    if( i<1 || i>db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] ){
+    if( bOk==0 || i<1 || i>db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] ){
       sqlite3ErrorMsg(pParse, "variable number must be between ?1 and ?%d",
           db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER]);
     }
     if( i>pParse->nVar ){
-      pParse->nVar = i;
+      pParse->nVar = (int)i;
     }
   }else{
     /* Wildcards like ":aaa", "$aaa" or "@aaa".  Reuse the same variable
@@ -68001,14 +69826,20 @@
     /* Could not found an existing table or index to use as the RHS b-tree.
     ** We will have to generate an ephemeral table to do the job.
     */
+    double savedNQueryLoop = pParse->nQueryLoop;
     int rMayHaveNull = 0;
     eType = IN_INDEX_EPH;
     if( prNotFound ){
       *prNotFound = rMayHaveNull = ++pParse->nMem;
-    }else if( pX->pLeft->iColumn<0 && !ExprHasAnyProperty(pX, EP_xIsSelect) ){
-      eType = IN_INDEX_ROWID;
+    }else{
+      testcase( pParse->nQueryLoop>(double)1 );
+      pParse->nQueryLoop = (double)1;
+      if( pX->pLeft->iColumn<0 && !ExprHasAnyProperty(pX, EP_xIsSelect) ){
+        eType = IN_INDEX_ROWID;
+      }
     }
     sqlite3CodeSubselect(pParse, pX, rMayHaveNull, eType==IN_INDEX_ROWID);
+    pParse->nQueryLoop = savedNQueryLoop;
   }else{
     pX->iTable = iTab;
   }
@@ -68017,8 +69848,8 @@
 #endif
 
 /*
-** Generate code for scalar subqueries used as an expression
-** and IN operators.  Examples:
+** Generate code for scalar subqueries used as a subquery expression, EXISTS,
+** or IN operators.  Examples:
 **
 **     (SELECT a FROM b)          -- subquery
 **     EXISTS (SELECT a FROM b)   -- EXISTS subquery
@@ -68081,10 +69912,10 @@
 
   switch( pExpr->op ){
     case TK_IN: {
-      char affinity;
-      KeyInfo keyInfo;
-      int addr;        /* Address of OP_OpenEphemeral instruction */
-      Expr *pLeft = pExpr->pLeft;
+      char affinity;              /* Affinity of the LHS of the IN */
+      KeyInfo keyInfo;            /* Keyinfo for the generated table */
+      int addr;                   /* Address of OP_OpenEphemeral instruction */
+      Expr *pLeft = pExpr->pLeft; /* the LHS of the IN operator */
 
       if( rMayHaveNull ){
         sqlite3VdbeAddOp2(v, OP_Null, 0, rMayHaveNull);
@@ -68107,6 +69938,7 @@
       */
       pExpr->iTable = pParse->nTab++;
       addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pExpr->iTable, !isRowid);
+      if( rMayHaveNull==0 ) sqlite3VdbeChangeP5(v, BTREE_UNORDERED);
       memset(&keyInfo, 0, sizeof(keyInfo));
       keyInfo.nField = 1;
 
@@ -68131,7 +69963,7 @@
           keyInfo.aColl[0] = sqlite3BinaryCompareCollSeq(pParse, pExpr->pLeft,
               pEList->a[0].pExpr);
         }
-      }else if( pExpr->x.pList!=0 ){
+      }else if( ALWAYS(pExpr->x.pList!=0) ){
         /* Case 2:     expr IN (exprlist)
         **
         ** For each expression, build an index key from the evaluation and
@@ -68201,7 +70033,6 @@
       ** an integer 0 (not exists) or 1 (exists) into a memory cell
       ** and record that memory cell in iColumn.
       */
-      static const Token one = { "1", 1 };  /* Token for literal value 1 */
       Select *pSel;                         /* SELECT statement to encode */
       SelectDest dest;                      /* How to deal with SELECt result */
 
@@ -68222,7 +70053,8 @@
         VdbeComment((v, "Init EXISTS result"));
       }
       sqlite3ExprDelete(pParse->db, pSel->pLimit);
-      pSel->pLimit = sqlite3PExpr(pParse, TK_INTEGER, 0, 0, &one);
+      pSel->pLimit = sqlite3PExpr(pParse, TK_INTEGER, 0, 0,
+                                  &sqlite3IntTokens[1]);
       if( sqlite3Select(pParse, pSel, &dest) ){
         return 0;
       }
@@ -68290,8 +70122,20 @@
   sqlite3ExprCachePush(pParse);
   r1 = sqlite3GetTempReg(pParse);
   sqlite3ExprCode(pParse, pExpr->pLeft, r1);
-  sqlite3VdbeAddOp2(v, OP_IsNull, r1, destIfNull);
 
+  /* If the LHS is NULL, then the result is either false or NULL depending
+  ** on whether the RHS is empty or not, respectively.
+  */
+  if( destIfNull==destIfFalse ){
+    /* Shortcut for the common case where the false and NULL outcomes are
+    ** the same. */
+    sqlite3VdbeAddOp2(v, OP_IsNull, r1, destIfNull);
+  }else{
+    int addr1 = sqlite3VdbeAddOp1(v, OP_NotNull, r1);
+    sqlite3VdbeAddOp2(v, OP_Rewind, pExpr->iTable, destIfFalse);
+    sqlite3VdbeAddOp2(v, OP_Goto, 0, destIfNull);
+    sqlite3VdbeJumpHere(v, addr1);
+  }
 
   if( eType==IN_INDEX_ROWID ){
     /* In this case, the RHS is the ROWID of table b-tree
@@ -68704,73 +70548,6 @@
 #endif /* SQLITE_DEBUG || SQLITE_COVERAGE_TEST */
 
 /*
-** If the last instruction coded is an ephemeral copy of any of
-** the registers in the nReg registers beginning with iReg, then
-** convert the last instruction from OP_SCopy to OP_Copy.
-*/
-SQLITE_PRIVATE void sqlite3ExprHardCopy(Parse *pParse, int iReg, int nReg){
-  VdbeOp *pOp;
-  Vdbe *v;
-
-  assert( pParse->db->mallocFailed==0 );
-  v = pParse->pVdbe;
-  assert( v!=0 );
-  pOp = sqlite3VdbeGetOp(v, -1);
-  assert( pOp!=0 );
-  if( pOp->opcode==OP_SCopy && pOp->p1>=iReg && pOp->p1<iReg+nReg ){
-    pOp->opcode = OP_Copy;
-  }
-}
-
-/*
-** Generate code to store the value of the iAlias-th alias in register
-** target.  The first time this is called, pExpr is evaluated to compute
-** the value of the alias.  The value is stored in an auxiliary register
-** and the number of that register is returned.  On subsequent calls,
-** the register number is returned without generating any code.
-**
-** Note that in order for this to work, code must be generated in the
-** same order that it is executed.
-**
-** Aliases are numbered starting with 1.  So iAlias is in the range
-** of 1 to pParse->nAlias inclusive.  
-**
-** pParse->aAlias[iAlias-1] records the register number where the value
-** of the iAlias-th alias is stored.  If zero, that means that the
-** alias has not yet been computed.
-*/
-static int codeAlias(Parse *pParse, int iAlias, Expr *pExpr, int target){
-#if 0
-  sqlite3 *db = pParse->db;
-  int iReg;
-  if( pParse->nAliasAlloc<pParse->nAlias ){
-    pParse->aAlias = sqlite3DbReallocOrFree(db, pParse->aAlias,
-                                 sizeof(pParse->aAlias[0])*pParse->nAlias );
-    testcase( db->mallocFailed && pParse->nAliasAlloc>0 );
-    if( db->mallocFailed ) return 0;
-    memset(&pParse->aAlias[pParse->nAliasAlloc], 0,
-           (pParse->nAlias-pParse->nAliasAlloc)*sizeof(pParse->aAlias[0]));
-    pParse->nAliasAlloc = pParse->nAlias;
-  }
-  assert( iAlias>0 && iAlias<=pParse->nAlias );
-  iReg = pParse->aAlias[iAlias-1];
-  if( iReg==0 ){
-    if( pParse->iCacheLevel>0 ){
-      iReg = sqlite3ExprCodeTarget(pParse, pExpr, target);
-    }else{
-      iReg = ++pParse->nMem;
-      sqlite3ExprCode(pParse, pExpr, iReg);
-      pParse->aAlias[iAlias-1] = iReg;
-    }
-  }
-  return iReg;
-#else
-  UNUSED_PARAMETER(iAlias);
-  return sqlite3ExprCodeTarget(pParse, pExpr, target);
-#endif
-}
-
-/*
 ** Generate code into the current Vdbe to evaluate the given
 ** expression.  Attempt to store the results in register "target".
 ** Return the register where results are stored.
@@ -68878,7 +70655,7 @@
       break;
     }
     case TK_AS: {
-      inReg = codeAlias(pParse, pExpr->iTable, pExpr->pLeft, target);
+      inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
       break;
     }
 #ifndef SQLITE_OMIT_CAST
@@ -69310,6 +71087,11 @@
         opCompare.op = TK_EQ;
         opCompare.pLeft = &cacheX;
         pTest = &opCompare;
+        /* Ticket b351d95f9cd5ef17e9d9dbae18f5ca8611190001:
+        ** The value in regFree1 might get SCopy-ed into the file result.
+        ** So make sure that the regFree1 register is not reused for other
+        ** purposes and possibly overwritten.  */
+        regFree1 = 0;
       }
       for(i=0; i<nExpr; i=i+2){
         sqlite3ExprCachePush(pParse);
@@ -69403,10 +71185,14 @@
   int inReg;
 
   assert( target>0 && target<=pParse->nMem );
-  inReg = sqlite3ExprCodeTarget(pParse, pExpr, target);
-  assert( pParse->pVdbe || pParse->db->mallocFailed );
-  if( inReg!=target && pParse->pVdbe ){
-    sqlite3VdbeAddOp2(pParse->pVdbe, OP_SCopy, inReg, target);
+  if( pExpr && pExpr->op==TK_REGISTER ){
+    sqlite3VdbeAddOp2(pParse->pVdbe, OP_Copy, pExpr->iTable, target);
+  }else{
+    inReg = sqlite3ExprCodeTarget(pParse, pExpr, target);
+    assert( pParse->pVdbe || pParse->db->mallocFailed );
+    if( inReg!=target && pParse->pVdbe ){
+      sqlite3VdbeAddOp2(pParse->pVdbe, OP_SCopy, inReg, target);
+    }
   }
   return target;
 }
@@ -69579,19 +71365,14 @@
   int i, n;
   assert( pList!=0 );
   assert( target>0 );
+  assert( pParse->pVdbe!=0 );  /* Never gets this far otherwise */
   n = pList->nExpr;
   for(pItem=pList->a, i=0; i<n; i++, pItem++){
-    if( pItem->iAlias ){
-      int iReg = codeAlias(pParse, pItem->iAlias, pItem->pExpr, target+i);
-      Vdbe *v = sqlite3GetVdbe(pParse);
-      if( iReg!=target+i ){
-        sqlite3VdbeAddOp2(v, OP_SCopy, iReg, target+i);
-      }
-    }else{
-      sqlite3ExprCode(pParse, pItem->pExpr, target+i);
-    }
-    if( doHardCopy && !pParse->db->mallocFailed ){
-      sqlite3ExprHardCopy(pParse, target, n);
+    Expr *pExpr = pItem->pExpr;
+    int inReg = sqlite3ExprCodeTarget(pParse, pExpr, target+i);
+    if( inReg!=target+i ){
+      sqlite3VdbeAddOp2(pParse->pVdbe, doHardCopy ? OP_Copy : OP_SCopy,
+                        inReg, target+i);
     }
   }
   return n;
@@ -71029,7 +72810,6 @@
   if( !pNew ) goto exit_begin_add_column;
   pParse->pNewTable = pNew;
   pNew->nRef = 1;
-  pNew->dbMem = pTab->dbMem;
   pNew->nCol = pTab->nCol;
   assert( pNew->nCol>0 );
   nAlloc = (((pNew->nCol-1)/8)*8)+8;
@@ -71182,6 +72962,7 @@
   int topOfLoop;               /* The top of the loop */
   int endOfLoop;               /* The end of the loop */
   int addr;                    /* The address of an instruction */
+  int jZeroRows = 0;           /* Jump from here if number of rows is zero */
   int iDb;                     /* Index of database containing pTab */
   int regTabname = iMem++;     /* Register containing table name */
   int regIdxname = iMem++;     /* Register containing index name */
@@ -71200,8 +72981,15 @@
 #endif
 
   v = sqlite3GetVdbe(pParse);
-  if( v==0 || NEVER(pTab==0) || pTab->pIndex==0 ){
-    /* Do no analysis for tables that have no indices */
+  if( v==0 || NEVER(pTab==0) ){
+    return;
+  }
+  if( pTab->pSelect ){
+    /* Do not gather statistics on views */
+    return;
+  }
+  if( memcmp(pTab->zName, "sqlite_", 7)==0 ){
+    /* Do not gather statistics on system tables */
     return;
   }
   assert( sqlite3BtreeHoldsAllMutexes(db) );
@@ -71218,6 +73006,7 @@
   sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);
 
   iIdxCur = pParse->nTab++;
+  sqlite3VdbeAddOp4(v, OP_String8, 0, regTabname, 0, pTab->zName, 0);
   for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
     int nCol = pIdx->nColumn;
     KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx);
@@ -71232,10 +73021,7 @@
         (char *)pKey, P4_KEYINFO_HANDOFF);
     VdbeComment((v, "%s", pIdx->zName));
 
-    /* Populate the registers containing the table and index names. */
-    if( pTab->pIndex==pIdx ){
-      sqlite3VdbeAddOp4(v, OP_String8, 0, regTabname, 0, pTab->zName, 0);
-    }
+    /* Populate the register containing the index name. */
     sqlite3VdbeAddOp4(v, OP_String8, 0, regIdxname, 0, pIdx->zName, 0);
 
 #ifdef SQLITE_ENABLE_STAT2
@@ -71370,8 +73156,10 @@
     ** If K>0 then it is always the case the D>0 so division by zero
     ** is never possible.
     */
-    addr = sqlite3VdbeAddOp1(v, OP_IfNot, iMem);
     sqlite3VdbeAddOp2(v, OP_SCopy, iMem, regSampleno);
+    if( jZeroRows==0 ){
+      jZeroRows = sqlite3VdbeAddOp1(v, OP_IfNot, iMem);
+    }
     for(i=0; i<nCol; i++){
       sqlite3VdbeAddOp4(v, OP_String8, 0, regTemp, 0, " ", 0);
       sqlite3VdbeAddOp3(v, OP_Concat, regTemp, regSampleno, regSampleno);
@@ -71385,13 +73173,35 @@
     sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur, regRowid);
     sqlite3VdbeAddOp3(v, OP_Insert, iStatCur, regRec, regRowid);
     sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
+  }
+
+  /* If the table has no indices, create a single sqlite_stat1 entry
+  ** containing NULL as the index name and the row count as the content.
+  */
+  if( pTab->pIndex==0 ){
+    sqlite3VdbeAddOp3(v, OP_OpenRead, iIdxCur, pTab->tnum, iDb);
+    VdbeComment((v, "%s", pTab->zName));
+    sqlite3VdbeAddOp2(v, OP_Count, iIdxCur, regSampleno);
+    sqlite3VdbeAddOp1(v, OP_Close, iIdxCur);
+  }else{
+    assert( jZeroRows>0 );
+    addr = sqlite3VdbeAddOp0(v, OP_Goto);
+    sqlite3VdbeJumpHere(v, jZeroRows);
+  }
+  sqlite3VdbeAddOp2(v, OP_Null, 0, regIdxname);
+  sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 3, regRec, "aaa", 0);
+  sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur, regRowid);
+  sqlite3VdbeAddOp3(v, OP_Insert, iStatCur, regRec, regRowid);
+  sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
+  if( pParse->nMem<regRec ) pParse->nMem = regRec;
+  if( jZeroRows ){
     sqlite3VdbeJumpHere(v, addr);
   }
 }
 
 /*
 ** Generate code that will cause the most recent index analysis to
-** be laoded into internal hash tables where is can be used.
+** be loaded into internal hash tables where is can be used.
 */
 static void loadAnalysis(Parse *pParse, int iDb){
   Vdbe *v = sqlite3GetVdbe(pParse);
@@ -71521,33 +73331,46 @@
 ** This callback is invoked once for each index when reading the
 ** sqlite_stat1 table.  
 **
-**     argv[0] = name of the index
-**     argv[1] = results of analysis - on integer for each column
+**     argv[0] = name of the table
+**     argv[1] = name of the index (might be NULL)
+**     argv[2] = results of analysis - on integer for each column
+**
+** Entries for which argv[1]==NULL simply record the number of rows in
+** the table.
 */
 static int analysisLoader(void *pData, int argc, char **argv, char **NotUsed){
   analysisInfo *pInfo = (analysisInfo*)pData;
   Index *pIndex;
-  int i, c;
+  Table *pTable;
+  int i, c, n;
   unsigned int v;
   const char *z;
 
-  assert( argc==2 );
+  assert( argc==3 );
   UNUSED_PARAMETER2(NotUsed, argc);
 
-  if( argv==0 || argv[0]==0 || argv[1]==0 ){
+  if( argv==0 || argv[0]==0 || argv[2]==0 ){
     return 0;
   }
-  pIndex = sqlite3FindIndex(pInfo->db, argv[0], pInfo->zDatabase);
-  if( pIndex==0 ){
+  pTable = sqlite3FindTable(pInfo->db, argv[0], pInfo->zDatabase);
+  if( pTable==0 ){
     return 0;
   }
-  z = argv[1];
-  for(i=0; *z && i<=pIndex->nColumn; i++){
+  if( argv[1] ){
+    pIndex = sqlite3FindIndex(pInfo->db, argv[1], pInfo->zDatabase);
+  }else{
+    pIndex = 0;
+  }
+  n = pIndex ? pIndex->nColumn : 0;
+  z = argv[2];
+  for(i=0; *z && i<=n; i++){
     v = 0;
     while( (c=z[0])>='0' && c<='9' ){
       v = v*10 + c - '0';
       z++;
     }
+    if( i==0 ) pTable->nRowEst = v;
+    if( pIndex==0 ) break;
     pIndex->aiRowEst[i] = v;
     if( *z==' ' ) z++;
   }
@@ -71558,21 +73381,20 @@
 ** If the Index.aSample variable is not NULL, delete the aSample[] array
 ** and its contents.
 */
-SQLITE_PRIVATE void sqlite3DeleteIndexSamples(Index *pIdx){
+SQLITE_PRIVATE void sqlite3DeleteIndexSamples(sqlite3 *db, Index *pIdx){
 #ifdef SQLITE_ENABLE_STAT2
   if( pIdx->aSample ){
     int j;
-    sqlite3 *dbMem = pIdx->pTable->dbMem;
     for(j=0; j<SQLITE_INDEX_SAMPLES; j++){
       IndexSample *p = &pIdx->aSample[j];
       if( p->eType==SQLITE_TEXT || p->eType==SQLITE_BLOB ){
-        sqlite3DbFree(pIdx->pTable->dbMem, p->u.z);
+        sqlite3DbFree(db, p->u.z);
       }
     }
-    sqlite3DbFree(dbMem, pIdx->aSample);
-    pIdx->aSample = 0;
+    sqlite3DbFree(db, pIdx->aSample);
   }
 #else
+  UNUSED_PARAMETER(db);
   UNUSED_PARAMETER(pIdx);
 #endif
 }
@@ -71611,7 +73433,8 @@
   for(i=sqliteHashFirst(&db->aDb[iDb].pSchema->idxHash);i;i=sqliteHashNext(i)){
     Index *pIdx = sqliteHashData(i);
     sqlite3DefaultRowEst(pIdx);
-    sqlite3DeleteIndexSamples(pIdx);
+    sqlite3DeleteIndexSamples(db, pIdx);
+    pIdx->aSample = 0;
   }
 
   /* Check to make sure the sqlite_stat1 table exists */
@@ -71623,7 +73446,7 @@
 
   /* Load new statistics out of the sqlite_stat1 table */
   zSql = sqlite3MPrintf(db, 
-      "SELECT idx, stat FROM %Q.sqlite_stat1", sInfo.zDatabase);
+      "SELECT tbl, idx, stat FROM %Q.sqlite_stat1", sInfo.zDatabase);
   if( zSql==0 ){
     rc = SQLITE_NOMEM;
   }else{
@@ -71655,18 +73478,17 @@
         Index *pIdx = sqlite3FindIndex(db, zIndex, sInfo.zDatabase);
         if( pIdx ){
           int iSample = sqlite3_column_int(pStmt, 1);
-          sqlite3 *dbMem = pIdx->pTable->dbMem;
-          assert( dbMem==db || dbMem==0 );
           if( iSample<SQLITE_INDEX_SAMPLES && iSample>=0 ){
             int eType = sqlite3_column_type(pStmt, 2);
 
             if( pIdx->aSample==0 ){
               static const int sz = sizeof(IndexSample)*SQLITE_INDEX_SAMPLES;
-              pIdx->aSample = (IndexSample *)sqlite3DbMallocZero(dbMem, sz);
+              pIdx->aSample = (IndexSample *)sqlite3DbMallocRaw(0, sz);
               if( pIdx->aSample==0 ){
                 db->mallocFailed = 1;
                 break;
               }
+	      memset(pIdx->aSample, 0, sz);
             }
 
             assert( pIdx->aSample );
@@ -71689,10 +73511,8 @@
                 if( n < 1){
                   pSample->u.z = 0;
                 }else{
-                  pSample->u.z = sqlite3DbMallocRaw(dbMem, n);
-                  if( pSample->u.z ){
-                    memcpy(pSample->u.z, z, n);
-                  }else{
+                  pSample->u.z = sqlite3DbStrNDup(0, z, n);
+                  if( pSample->u.z==0 ){
                     db->mallocFailed = 1;
                     break;
                   }
@@ -71843,9 +73663,8 @@
   ** it to obtain the database schema. At this point the schema may
   ** or may not be initialised.
   */
-  rc = sqlite3BtreeFactory(db, zFile, 0, SQLITE_DEFAULT_CACHE_SIZE,
-                           db->openFlags | SQLITE_OPEN_MAIN_DB,
-                           &aNew->pBt);
+  rc = sqlite3BtreeOpen(zFile, db, &aNew->pBt, 0,
+                        db->openFlags | SQLITE_OPEN_MAIN_DB);
   db->nDb++;
   if( rc==SQLITE_CONSTRAINT ){
     rc = SQLITE_ERROR;
@@ -71862,8 +73681,6 @@
     }
     pPager = sqlite3BtreePager(aNew->pBt);
     sqlite3PagerLockingMode(pPager, db->dfltLockMode);
-    /* journal_mode set by the OP_JournalMode opcode that will following
-    ** the OP_Function opcode that invoked this function. */
     sqlite3BtreeSecureDelete(aNew->pBt,
                              sqlite3BtreeSecureDelete(db->aDb[0].pBt,-1) );
   }
@@ -72059,17 +73876,6 @@
     sqlite3VdbeChangeP5(v, (u8)(pFunc->nArg));
     sqlite3VdbeChangeP4(v, -1, (char *)pFunc, P4_FUNCDEF);
 
-    if( type==SQLITE_ATTACH ){
-      /* On an attach, also set the journal mode.  Note that
-      ** sqlite3VdbeUsesBtree() is not call here since the iDb index
-      ** will be out of range prior to the new database being attached.
-      ** The OP_JournalMode opcode will all sqlite3VdbeUsesBtree() for us.
-      */
-      sqlite3VdbeAddOp3(v, OP_JournalMode, db->nDb, regArgs+3, 
-                           db->dfltJournalMode);
-      sqlite3VdbeChangeP5(v, 1);
-    }
-
     /* Code an OP_Expire. For an ATTACH statement, set P1 to true (expire this
     ** statement only). For DETACH, set it to false (expire all existing
     ** statements).
@@ -72868,34 +74674,15 @@
 /*
 ** Reclaim the memory used by an index
 */
-static void freeIndex(Index *p){
-  sqlite3 *db = p->pTable->dbMem;
+static void freeIndex(sqlite3 *db, Index *p){
 #ifndef SQLITE_OMIT_ANALYZE
-  sqlite3DeleteIndexSamples(p);
+  sqlite3DeleteIndexSamples(db, p);
 #endif
   sqlite3DbFree(db, p->zColAff);
   sqlite3DbFree(db, p);
 }
 
 /*
-** Remove the given index from the index hash table, and free
-** its memory structures.
-**
-** The index is removed from the database hash tables but
-** it is not unlinked from the Table that it indexes.
-** Unlinking from the Table must be done by the calling function.
-*/
-static void sqlite3DeleteIndex(Index *p){
-  Index *pOld;
-  const char *zName = p->zName;
-
-  pOld = sqlite3HashInsert(&p->pSchema->idxHash, zName,
-                           sqlite3Strlen30(zName), 0);
-  assert( pOld==0 || pOld==p );
-  freeIndex(p);
-}
-
-/*
 ** For the index called zIdxName which is found in the database iDb,
 ** unlike that index from its Table then remove the index from
 ** the index hash table and free all memory structures associated
@@ -72921,7 +74708,7 @@
         p->pNext = pIndex->pNext;
       }
     }
-    freeIndex(pIndex);
+    freeIndex(db, pIndex);
   }
   db->flags |= SQLITE_InternChanges;
 }
@@ -72992,13 +74779,12 @@
 }
 
 /*
-** Clear the column names from a table or view.
+** Delete memory allocated for the column names of a table or view (the
+** Table.aCol[] array).
 */
-static void sqliteResetColumnNames(Table *pTable){
+static void sqliteDeleteColumnNames(sqlite3 *db, Table *pTable){
   int i;
   Column *pCol;
-  sqlite3 *db = pTable->dbMem;
-  testcase( db==0 );
   assert( pTable!=0 );
   if( (pCol = pTable->aCol)!=0 ){
     for(i=0; i<pTable->nCol; i++, pCol++){
@@ -73010,8 +74796,6 @@
     }
     sqlite3DbFree(db, pTable->aCol);
   }
-  pTable->aCol = 0;
-  pTable->nCol = 0;
 }
 
 /*
@@ -73023,42 +74807,44 @@
 ** memory structures of the indices and foreign keys associated with 
 ** the table.
 */
-SQLITE_PRIVATE void sqlite3DeleteTable(Table *pTable){
+SQLITE_PRIVATE void sqlite3DeleteTable(sqlite3 *db, Table *pTable){
   Index *pIndex, *pNext;
-  sqlite3 *db;
 
-  if( pTable==0 ) return;
-  db = pTable->dbMem;
-  testcase( db==0 );
+  assert( !pTable || pTable->nRef>0 );
 
   /* Do not delete the table until the reference count reaches zero. */
-  pTable->nRef--;
-  if( pTable->nRef>0 ){
-    return;
-  }
-  assert( pTable->nRef==0 );
+  if( !pTable ) return;
+  if( ((!db || db->pnBytesFreed==0) && (--pTable->nRef)>0) ) return;
 
-  /* Delete all indices associated with this table
-  */
+  /* Delete all indices associated with this table. */
   for(pIndex = pTable->pIndex; pIndex; pIndex=pNext){
     pNext = pIndex->pNext;
     assert( pIndex->pSchema==pTable->pSchema );
-    sqlite3DeleteIndex(pIndex);
+    if( !db || db->pnBytesFreed==0 ){
+      char *zName = pIndex->zName; 
+      TESTONLY ( Index *pOld = ) sqlite3HashInsert(
+	  &pIndex->pSchema->idxHash, zName, sqlite3Strlen30(zName), 0
+      );
+      assert( pOld==pIndex || pOld==0 );
+    }
+    freeIndex(db, pIndex);
   }
 
   /* Delete any foreign keys attached to this table. */
-  sqlite3FkDelete(pTable);
+  sqlite3FkDelete(db, pTable);
 
   /* Delete the Table structure itself.
   */
-  sqliteResetColumnNames(pTable);
+  sqliteDeleteColumnNames(db, pTable);
   sqlite3DbFree(db, pTable->zName);
   sqlite3DbFree(db, pTable->zColAff);
   sqlite3SelectDelete(db, pTable->pSelect);
 #ifndef SQLITE_OMIT_CHECK
   sqlite3ExprDelete(db, pTable->pCheck);
 #endif
-  sqlite3VtabClear(pTable);
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+  sqlite3VtabClear(db, pTable);
+#endif
   sqlite3DbFree(db, pTable);
 }
 
@@ -73077,7 +74863,7 @@
   pDb = &db->aDb[iDb];
   p = sqlite3HashInsert(&pDb->pSchema->tblHash, zTabName,
                         sqlite3Strlen30(zTabName),0);
-  sqlite3DeleteTable(p);
+  sqlite3DeleteTable(db, p);
   db->flags |= SQLITE_InternChanges;
 }
 
@@ -73345,7 +75131,7 @@
   pTable->iPKey = -1;
   pTable->pSchema = db->aDb[iDb].pSchema;
   pTable->nRef = 1;
-  pTable->dbMem = 0;
+  pTable->nRowEst = 1000000;
   assert( pParse->pNewTable==0 );
   pParse->pNewTable = pTable;
 
@@ -73897,7 +75683,7 @@
     zEnd = "\n)";
   }
   n += 35 + 6*p->nCol;
-  zStmt = sqlite3Malloc( n );
+  zStmt = sqlite3DbMallocRaw(0, n);
   if( zStmt==0 ){
     db->mallocFailed = 1;
     return 0;
@@ -74078,7 +75864,7 @@
         p->aCol = pSelTab->aCol;
         pSelTab->nCol = 0;
         pSelTab->aCol = 0;
-        sqlite3DeleteTable(pSelTab);
+        sqlite3DeleteTable(db, pSelTab);
       }
     }
 
@@ -74192,12 +75978,10 @@
   }
   sqlite3StartTable(pParse, pName1, pName2, isTemp, 1, 0, noErr);
   p = pParse->pNewTable;
-  if( p==0 ){
+  if( p==0 || pParse->nErr ){
     sqlite3SelectDelete(db, pSelect);
     return;
   }
-  assert( pParse->nErr==0 ); /* If sqlite3StartTable return non-NULL then
-                             ** there could not have been an error */
   sqlite3TwoPartName(pParse, pName1, pName2, &pName);
   iDb = sqlite3SchemaToIndex(db, p->pSchema);
   if( sqlite3FixInit(&sFix, pParse, iDb, "view", pName)
@@ -74322,7 +76106,7 @@
       pTable->aCol = pSelTab->aCol;
       pSelTab->nCol = 0;
       pSelTab->aCol = 0;
-      sqlite3DeleteTable(pSelTab);
+      sqlite3DeleteTable(db, pSelTab);
       pTable->pSchema->flags |= DB_UnresetViews;
     }else{
       pTable->nCol = 0;
@@ -74347,7 +76131,9 @@
   for(i=sqliteHashFirst(&db->aDb[idx].pSchema->tblHash); i;i=sqliteHashNext(i)){
     Table *pTab = sqliteHashData(i);
     if( pTab->pSelect ){
-      sqliteResetColumnNames(pTab);
+      sqliteDeleteColumnNames(db, pTab);
+      pTab->aCol = 0;
+      pTab->nCol = 0;
     }
   }
   DbClearProperty(db, idx, DB_UnresetViews);
@@ -75344,7 +77130,7 @@
   /* Clean up before exiting */
 exit_create_index:
   if( pIndex ){
-    sqlite3_free(pIndex->zColAff);
+    sqlite3DbFree(db, pIndex->zColAff);
     sqlite3DbFree(db, pIndex);
   }
   sqlite3ExprListDelete(db, pList);
@@ -75374,14 +77160,14 @@
 SQLITE_PRIVATE void sqlite3DefaultRowEst(Index *pIdx){
   unsigned *a = pIdx->aiRowEst;
   int i;
+  unsigned n;
   assert( a!=0 );
-  a[0] = 1000000;
-  for(i=pIdx->nColumn; i>=5; i--){
-    a[i] = 5;
-  }
-  while( i>=1 ){
-    a[i] = 11 - i;
-    i--;
+  a[0] = pIdx->pTable->nRowEst;
+  if( a[0]<10 ) a[0] = 10;
+  n = 10;
+  for(i=1; i<=pIdx->nColumn; i++){
+    a[i] = n;
+    if( n>5 ) n--;
   }
   if( pIdx->onError!=OE_None ){
     a[pIdx->nColumn] = 1;
@@ -75723,7 +77509,7 @@
     sqlite3DbFree(db, pItem->zName);
     sqlite3DbFree(db, pItem->zAlias);
     sqlite3DbFree(db, pItem->zIndex);
-    sqlite3DeleteTable(pItem->pTab);
+    sqlite3DeleteTable(db, pItem->pTab);
     sqlite3SelectDelete(db, pItem->pSelect);
     sqlite3ExprDelete(db, pItem->pOn);
     sqlite3IdListDelete(db, pItem->pUsing);
@@ -75933,7 +77719,7 @@
           SQLITE_OPEN_DELETEONCLOSE |
           SQLITE_OPEN_TEMP_DB;
 
-    rc = sqlite3BtreeFactory(db, 0, 0, SQLITE_DEFAULT_CACHE_SIZE, flags, &pBt);
+    rc = sqlite3BtreeOpen(0, db, &pBt, 0, flags);
     if( rc!=SQLITE_OK ){
       sqlite3ErrorMsg(pParse, "unable to open a temporary database "
         "file for storing temporary tables");
@@ -75946,7 +77732,6 @@
       db->mallocFailed = 1;
       return 1;
     }
-    sqlite3PagerSetJournalMode(sqlite3BtreePager(pBt), db->dfltJournalMode);
   }
   return 0;
 }
@@ -76591,7 +78376,7 @@
   ** priority to built-in functions.
   **
   ** Except, if createFlag is true, that means that we are trying to
-  ** install a new function.  Whatever FuncDef structure is returned will
+  ** install a new function.  Whatever FuncDef structure is returned it will
   ** have fields overwritten with new information appropriate for the
   ** new function.  But the FuncDefs for built-in functions are read-only.
   ** So we must not search for built-ins when creating a new function.
@@ -76655,8 +78440,7 @@
   sqlite3HashInit(&pSchema->tblHash);
   for(pElem=sqliteHashFirst(&temp1); pElem; pElem=sqliteHashNext(pElem)){
     Table *pTab = sqliteHashData(pElem);
-    assert( pTab->dbMem==0 );
-    sqlite3DeleteTable(pTab);
+    sqlite3DeleteTable(0, pTab);
   }
   sqlite3HashClear(&temp1);
   sqlite3HashClear(&pSchema->fkeyHash);
@@ -76673,7 +78457,7 @@
   if( pBt ){
     p = (Schema *)sqlite3BtreeSchema(pBt, sizeof(Schema), sqlite3SchemaFree);
   }else{
-    p = (Schema *)sqlite3MallocZero(sizeof(Schema));
+    p = (Schema *)sqlite3DbMallocZero(0, sizeof(Schema));
   }
   if( !p ){
     db->mallocFailed = 1;
@@ -76714,7 +78498,7 @@
   Table *pTab;
   assert( pItem && pSrc->nSrc==1 );
   pTab = sqlite3LocateTable(pParse, 0, pItem->zName, pItem->zDatabase);
-  sqlite3DeleteTable(pItem->pTab);
+  sqlite3DeleteTable(pParse->db, pItem->pTab);
   pItem->pTab = pTab;
   if( pTab ){
     pTab->nRef++;
@@ -78111,8 +79895,10 @@
   const char *zOptName;
   assert( argc==1 );
   UNUSED_PARAMETER(argc);
-  /* IMP: R-xxxx This function is an SQL wrapper around the
-  ** sqlite3_compileoption_used() C interface. */
+  /* IMP: R-39564-36305 The sqlite_compileoption_used() SQL
+  ** function is a wrapper around the sqlite3_compileoption_used() C/C++
+  ** function.
+  */
   if( (zOptName = (const char*)sqlite3_value_text(argv[0]))!=0 ){
     sqlite3_result_int(context, sqlite3_compileoption_used(zOptName));
   }
@@ -78133,8 +79919,9 @@
   int n;
   assert( argc==1 );
   UNUSED_PARAMETER(argc);
-  /* IMP: R-xxxx This function is an SQL wrapper around the
-  ** sqlite3_compileoption_get() C interface. */
+  /* IMP: R-04922-24076 The sqlite_compileoption_get() SQL function
+  ** is a wrapper around the sqlite3_compileoption_get() C/C++ function.
+  */
   n = sqlite3_value_int(argv[0]);
   sqlite3_result_text(context, sqlite3_compileoption_get(n), -1, SQLITE_STATIC);
 }
@@ -78333,14 +80120,14 @@
       testcase( nOut-2==db->aLimit[SQLITE_LIMIT_LENGTH] );
       if( nOut-1>db->aLimit[SQLITE_LIMIT_LENGTH] ){
         sqlite3_result_error_toobig(context);
-        sqlite3DbFree(db, zOut);
+        sqlite3_free(zOut);
         return;
       }
       zOld = zOut;
       zOut = sqlite3_realloc(zOut, (int)nOut);
       if( zOut==0 ){
         sqlite3_result_error_nomem(context);
-        sqlite3DbFree(db, zOld);
+        sqlite3_free(zOld);
         return;
       }
       memcpy(&zOut[j], zRep, nRep);
@@ -78701,7 +80488,7 @@
   if( pAccum ){
     sqlite3 *db = sqlite3_context_db_handle(context);
     int firstTerm = pAccum->useMalloc==0;
-    pAccum->useMalloc = 1;
+    pAccum->useMalloc = 2;
     pAccum->mxAlloc = db->aLimit[SQLITE_LIMIT_LENGTH];
     if( !firstTerm ){
       if( argc==2 ){
@@ -78770,10 +80557,10 @@
   }else{
     pInfo = (struct compareInfo*)&likeInfoNorm;
   }
-  sqlite3CreateFunc(db, "like", 2, SQLITE_ANY, pInfo, likeFunc, 0, 0);
-  sqlite3CreateFunc(db, "like", 3, SQLITE_ANY, pInfo, likeFunc, 0, 0);
+  sqlite3CreateFunc(db, "like", 2, SQLITE_ANY, pInfo, likeFunc, 0, 0, 0);
+  sqlite3CreateFunc(db, "like", 3, SQLITE_ANY, pInfo, likeFunc, 0, 0, 0);
   sqlite3CreateFunc(db, "glob", 2, SQLITE_ANY, 
-      (struct compareInfo*)&globInfo, likeFunc, 0,0);
+      (struct compareInfo*)&globInfo, likeFunc, 0, 0, 0);
   setLikeOptFlag(db, "glob", SQLITE_FUNC_LIKE | SQLITE_FUNC_CASE);
   setLikeOptFlag(db, "like", 
       caseSensitive ? (SQLITE_FUNC_LIKE | SQLITE_FUNC_CASE) : SQLITE_FUNC_LIKE);
@@ -79298,7 +81085,7 @@
       sqlite3VdbeAddOp3(v, OP_OpenRead, iCur, pIdx->tnum, iDb);
       sqlite3VdbeChangeP4(v, -1, (char*)pKey, P4_KEYINFO_HANDOFF);
       for(i=0; i<nCol; i++){
-        sqlite3VdbeAddOp2(v, OP_SCopy, aiCol[i]+1+regData, regTemp+i);
+        sqlite3VdbeAddOp2(v, OP_Copy, aiCol[i]+1+regData, regTemp+i);
       }
   
       /* If the parent table is the same as the child table, and we are about
@@ -79418,7 +81205,8 @@
       if( pIdx ){
         Column *pCol;
         iCol = pIdx->aiColumn[i];
-        pCol = &pIdx->pTable->aCol[iCol];
+        pCol = &pTab->aCol[iCol];
+        if( pTab->iPKey==iCol ) iCol = -1;
         pLeft->iTable = regData+iCol+1;
         pLeft->affinity = pCol->affinity;
         pLeft->pColl = sqlite3LocateCollSeq(pParse, pCol->zColl);
@@ -79979,11 +81767,7 @@
       pWhere = 0;
     }
 
-    /* In the current implementation, pTab->dbMem==0 for all tables except
-    ** for temporary tables used to describe subqueries.  And temporary
-    ** tables do not have foreign key constraints.  Hence, pTab->dbMem
-    ** should always be 0 there.
-    */
+    /* Disable lookaside memory allocation */
     enableLookaside = db->lookaside.bEnabled;
     db->lookaside.bEnabled = 0;
 
@@ -80073,37 +81857,39 @@
 ** table pTab. Remove the deleted foreign keys from the Schema.fkeyHash
 ** hash table.
 */
-SQLITE_PRIVATE void sqlite3FkDelete(Table *pTab){
+SQLITE_PRIVATE void sqlite3FkDelete(sqlite3 *db, Table *pTab){
   FKey *pFKey;                    /* Iterator variable */
   FKey *pNext;                    /* Copy of pFKey->pNextFrom */
 
   for(pFKey=pTab->pFKey; pFKey; pFKey=pNext){
 
     /* Remove the FK from the fkeyHash hash table. */
-    if( pFKey->pPrevTo ){
-      pFKey->pPrevTo->pNextTo = pFKey->pNextTo;
-    }else{
-      void *data = (void *)pFKey->pNextTo;
-      const char *z = (data ? pFKey->pNextTo->zTo : pFKey->zTo);
-      sqlite3HashInsert(&pTab->pSchema->fkeyHash, z, sqlite3Strlen30(z), data);
+    if( !db || db->pnBytesFreed==0 ){
+      if( pFKey->pPrevTo ){
+        pFKey->pPrevTo->pNextTo = pFKey->pNextTo;
+      }else{
+        void *p = (void *)pFKey->pNextTo;
+        const char *z = (p ? pFKey->pNextTo->zTo : pFKey->zTo);
+        sqlite3HashInsert(&pTab->pSchema->fkeyHash, z, sqlite3Strlen30(z), p);
+      }
+      if( pFKey->pNextTo ){
+        pFKey->pNextTo->pPrevTo = pFKey->pPrevTo;
+      }
     }
-    if( pFKey->pNextTo ){
-      pFKey->pNextTo->pPrevTo = pFKey->pPrevTo;
-    }
-
-    /* Delete any triggers created to implement actions for this FK. */
-#ifndef SQLITE_OMIT_TRIGGER
-    fkTriggerDelete(pTab->dbMem, pFKey->apTrigger[0]);
-    fkTriggerDelete(pTab->dbMem, pFKey->apTrigger[1]);
-#endif
 
     /* EV: R-30323-21917 Each foreign key constraint in SQLite is
     ** classified as either immediate or deferred.
     */
     assert( pFKey->isDeferred==0 || pFKey->isDeferred==1 );
 
+    /* Delete any triggers created to implement actions for this FK. */
+#ifndef SQLITE_OMIT_TRIGGER
+    fkTriggerDelete(db, pFKey->apTrigger[0]);
+    fkTriggerDelete(db, pFKey->apTrigger[1]);
+#endif
+
     pNext = pFKey->pNextFrom;
-    sqlite3DbFree(pTab->dbMem, pFKey);
+    sqlite3DbFree(db, pFKey);
   }
 }
 #endif /* ifndef SQLITE_OMIT_FOREIGN_KEY */
@@ -80178,7 +81964,7 @@
     int n;
     Table *pTab = pIdx->pTable;
     sqlite3 *db = sqlite3VdbeDb(v);
-    pIdx->zColAff = (char *)sqlite3Malloc(pIdx->nColumn+2);
+    pIdx->zColAff = (char *)sqlite3DbMallocRaw(0, pIdx->nColumn+2);
     if( !pIdx->zColAff ){
       db->mallocFailed = 1;
       return 0;
@@ -80220,7 +82006,7 @@
     int i;
     sqlite3 *db = sqlite3VdbeDb(v);
 
-    zColAff = (char *)sqlite3Malloc(pTab->nCol+1);
+    zColAff = (char *)sqlite3DbMallocRaw(0, pTab->nCol+1);
     if( !zColAff ){
       db->mallocFailed = 1;
       return;
@@ -81331,6 +83117,7 @@
     if( onError==OE_Ignore ){
       sqlite3VdbeAddOp2(v, OP_Goto, 0, ignoreDest);
     }else{
+      if( onError==OE_Replace ) onError = OE_Abort; /* IMP: R-15569-63625 */
       sqlite3HaltConstraint(pParse, onError, 0, 0);
     }
     sqlite3VdbeResolveLabel(v, allOk);
@@ -82845,13 +84632,11 @@
   handle = sqlite3OsDlOpen(pVfs, zFile);
   if( handle==0 ){
     if( pzErrMsg ){
-      zErrmsg = sqlite3StackAllocZero(db, nMsg);
+      *pzErrMsg = zErrmsg = sqlite3_malloc(nMsg);
       if( zErrmsg ){
         sqlite3_snprintf(nMsg, zErrmsg, 
             "unable to open shared library [%s]", zFile);
         sqlite3OsDlError(pVfs, nMsg-1, zErrmsg);
-        *pzErrMsg = sqlite3DbStrDup(0, zErrmsg);
-        sqlite3StackFree(db, zErrmsg);
       }
     }
     return SQLITE_ERROR;
@@ -82860,13 +84645,11 @@
                    sqlite3OsDlSym(pVfs, handle, zProc);
   if( xInit==0 ){
     if( pzErrMsg ){
-      zErrmsg = sqlite3StackAllocZero(db, nMsg);
+      *pzErrMsg = zErrmsg = sqlite3_malloc(nMsg);
       if( zErrmsg ){
         sqlite3_snprintf(nMsg, zErrmsg,
             "no entry point [%s] in shared library [%s]", zProc,zFile);
         sqlite3OsDlError(pVfs, nMsg-1, zErrmsg);
-        *pzErrMsg = sqlite3DbStrDup(0, zErrmsg);
-        sqlite3StackFree(db, zErrmsg);
       }
       sqlite3OsDlClose(pVfs, handle);
     }
@@ -83615,8 +85398,11 @@
   **                      (delete|persist|off|truncate|memory|wal|off)
   */
   if( sqlite3StrICmp(zLeft,"journal_mode")==0 ){
-    int eMode;                    /* One of the PAGER_JOURNALMODE_XXX symbols */
+    int eMode;        /* One of the PAGER_JOURNALMODE_XXX symbols */
+    int ii;           /* Loop counter */
 
+    /* Force the schema to be loaded on all databases.  This cases all
+    ** database files to be opened and the journal_modes set. */
     if( sqlite3ReadSchema(pParse) ){
       goto pragma_out;
     }
@@ -83625,6 +85411,8 @@
     sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "journal_mode", SQLITE_STATIC);
 
     if( zRight==0 ){
+      /* If there is no "=MODE" part of the pragma, do a query for the
+      ** current mode */
       eMode = PAGER_JOURNALMODE_QUERY;
     }else{
       const char *zMode;
@@ -83633,40 +85421,22 @@
         if( sqlite3StrNICmp(zRight, zMode, n)==0 ) break;
       }
       if( !zMode ){
+        /* If the "=MODE" part does not match any known journal mode,
+        ** then do a query */
         eMode = PAGER_JOURNALMODE_QUERY;
       }
     }
-    if( pId2->n==0 && eMode==PAGER_JOURNALMODE_QUERY ){
-      /* Simple "PRAGMA journal_mode;" statement. This is a query for
-      ** the current default journal mode (which may be different to
-      ** the journal-mode of the main database).
-      */
-      eMode = db->dfltJournalMode;
-      sqlite3VdbeAddOp2(v, OP_String8, 0, 1);
-      sqlite3VdbeChangeP4(v, -1, sqlite3JournalModename(eMode), P4_STATIC);
-    }else{
-      int ii;
-
-      if( pId2->n==0 ){
-        /* When there is no database name before the "journal_mode" keyword
-        ** in the PRAGMA, then the journal-mode will be set on
-        ** all attached databases, as well as the main db file.
-        **
-        ** Also, the sqlite3.dfltJournalMode variable is set so that
-        ** any subsequently attached databases also use the specified
-        ** journal mode.
-        */
-        db->dfltJournalMode = (u8)eMode;
-      }
-
-      for(ii=db->nDb-1; ii>=0; ii--){
-        if( db->aDb[ii].pBt && (ii==iDb || pId2->n==0) ){
-          sqlite3VdbeUsesBtree(v, ii);
-          sqlite3VdbeAddOp3(v, OP_JournalMode, ii, 1, eMode);
-        }
+    if( eMode==PAGER_JOURNALMODE_QUERY && pId2->n==0 ){
+      /* Convert "PRAGMA journal_mode" into "PRAGMA main.journal_mode" */
+      iDb = 0;
+      pId2->n = 1;
+    }
+    for(ii=db->nDb-1; ii>=0; ii--){
+      if( db->aDb[ii].pBt && (ii==iDb || pId2->n==0) ){
+        sqlite3VdbeUsesBtree(v, ii);
+        sqlite3VdbeAddOp3(v, OP_JournalMode, ii, 1, eMode);
       }
     }
-
     sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
   }else
 
@@ -83858,7 +85628,7 @@
       }
       sqlite3_free(sqlite3_temp_directory);
       if( zRight[0] ){
-        sqlite3_temp_directory = sqlite3DbStrDup(0, zRight);
+        sqlite3_temp_directory = sqlite3_mprintf("%s", zRight);
       }else{
         sqlite3_temp_directory = 0;
       }
@@ -85279,7 +87049,6 @@
   while( pParse->pTriggerPrg ){
     TriggerPrg *pT = pParse->pTriggerPrg;
     pParse->pTriggerPrg = pT->pNext;
-    sqlite3VdbeProgramDelete(db, pT->pProgram, 0);
     sqlite3DbFree(db, pT);
   }
 
@@ -85963,11 +87732,13 @@
   sqlite3ReleaseTempReg(pParse, r1);
 }
 
+#ifndef SQLITE_OMIT_SUBQUERY
 /*
 ** Generate an error message when a SELECT is used within a subexpression
 ** (example:  "a IN (SELECT * FROM table)") but it has more than 1 result
-** column.  We do this in a subroutine because the error occurs in multiple
-** places.
+** column.  We do this in a subroutine because the error used to occur
+** in multiple places.  (The error only occurs in one place now, but we
+** retain the subroutine to minimize code disruption.)
 */
 static int checkForMultiColumnSelectError(
   Parse *pParse,       /* Parse context. */
@@ -85983,6 +87754,7 @@
     return 0;
   }
 }
+#endif
 
 /*
 ** This routine generates the code for the inside of the inner loop
@@ -86062,10 +87834,6 @@
     }
   }
 
-  if( checkForMultiColumnSelectError(pParse, pDest, pEList->nExpr) ){
-    return;
-  }
-
   switch( eDest ){
     /* In this mode, write each query result to the key of the temporary
     ** table iParm.
@@ -86770,16 +88538,15 @@
     return 0;
   }
   /* The sqlite3ResultSetOfSelect() is only used n contexts where lookaside
-  ** is disabled, so we might as well hard-code pTab->dbMem to NULL. */
+  ** is disabled */
   assert( db->lookaside.bEnabled==0 );
-  pTab->dbMem = 0;
   pTab->nRef = 1;
   pTab->zName = 0;
   selectColumnsFromExprList(pParse, pSelect->pEList, &pTab->nCol, &pTab->aCol);
   selectAddColumnTypeAndCollation(pParse, pTab->nCol, pTab->aCol, pSelect);
   pTab->iPKey = -1;
   if( db->mallocFailed ){
-    sqlite3DeleteTable(pTab);
+    sqlite3DeleteTable(db, pTab);
     return 0;
   }
   return pTab;
@@ -86976,6 +88743,7 @@
   if( dest.eDest==SRT_EphemTab ){
     assert( p->pEList );
     sqlite3VdbeAddOp2(v, OP_OpenEphemeral, dest.iParm, p->pEList->nExpr);
+    sqlite3VdbeChangeP5(v, BTREE_UNORDERED);
     dest.eDest = SRT_Table;
   }
 
@@ -87271,7 +89039,7 @@
 ** regReturn is the number of the register holding the subroutine
 ** return address.
 **
-** If regPrev>0 then it is a the first register in a vector that
+** If regPrev>0 then it is the first register in a vector that
 ** records the previous output.  mem[regPrev] is a flag that is false
 ** if there has been no previous output.  If regPrev>0 then code is
 ** generated to suppress duplicates.  pKeyInfo is used for comparing
@@ -87968,12 +89736,13 @@
 **   (2)  The subquery is not an aggregate or the outer query is not a join.
 **
 **   (3)  The subquery is not the right operand of a left outer join
-**        (Originally ticket #306.  Strenghtened by ticket #3300)
+**        (Originally ticket #306.  Strengthened by ticket #3300)
 **
-**   (4)  The subquery is not DISTINCT or the outer query is not a join.
+**   (4)  The subquery is not DISTINCT.
 **
-**   (5)  The subquery is not DISTINCT or the outer query does not use
-**        aggregates.
+**  (**)  At one point restrictions (4) and (5) defined a subset of DISTINCT
+**        sub-queries that were excluded from this optimization. Restriction 
+**        (4) has since been expanded to exclude all DISTINCT subqueries.
 **
 **   (6)  The subquery does not use aggregates or the outer query is not
 **        DISTINCT.
@@ -87993,9 +89762,9 @@
 **  (**)  Not implemented.  Subsumed into restriction (3).  Was previously
 **        a separate restriction deriving from ticket #350.
 **
-**  (13)  The subquery and outer query do not both use LIMIT
+**  (13)  The subquery and outer query do not both use LIMIT.
 **
-**  (14)  The subquery does not use OFFSET
+**  (14)  The subquery does not use OFFSET.
 **
 **  (15)  The outer query is not part of a compound select or the
 **        subquery does not have a LIMIT clause.
@@ -88086,9 +89855,9 @@
     return 0;                                            /* Restriction (15) */
   }
   if( pSubSrc->nSrc==0 ) return 0;                       /* Restriction (7)  */
-  if( ((pSub->selFlags & SF_Distinct)!=0 || pSub->pLimit) 
-         && (pSrc->nSrc>1 || isAgg) ){          /* Restrictions (4)(5)(8)(9) */
-     return 0;       
+  if( pSub->selFlags & SF_Distinct ) return 0;           /* Restriction (5)  */
+  if( pSub->pLimit && (pSrc->nSrc>1 || isAgg) ){
+     return 0;         /* Restrictions (8)(9) */
   }
   if( (p->selFlags & SF_Distinct)!=0 && subqueryIsAgg ){
      return 0;         /* Restriction (6)  */
@@ -88568,7 +90337,6 @@
       sqlite3WalkSelect(pWalker, pSel);
       pFrom->pTab = pTab = sqlite3DbMallocZero(db, sizeof(Table));
       if( pTab==0 ) return WRC_Abort;
-      pTab->dbMem = db->lookaside.bEnabled ? db : 0;
       pTab->nRef = 1;
       pTab->zName = sqlite3MPrintf(db, "sqlite_subquery_%p_", (void*)pTab);
       while( pSel->pPrior ){ pSel = pSel->pPrior; }
@@ -88938,7 +90706,7 @@
     if( pList ){
       nArg = pList->nExpr;
       regAgg = sqlite3GetTempRange(pParse, nArg);
-      sqlite3ExprCodeExprList(pParse, pList, regAgg, 0);
+      sqlite3ExprCodeExprList(pParse, pList, regAgg, 1);
     }else{
       nArg = 0;
       regAgg = 0;
@@ -89098,6 +90866,15 @@
   v = sqlite3GetVdbe(pParse);
   if( v==0 ) goto select_end;
 
+  /* If writing to memory or generating a set
+  ** only a single column may be output.
+  */
+#ifndef SQLITE_OMIT_SUBQUERY
+  if( checkForMultiColumnSelectError(pParse, pDest, pEList->nExpr) ){
+    goto select_end;
+  }
+#endif
+
   /* Generate code for all sub-queries in the FROM clause
   */
 #if !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW)
@@ -89171,15 +90948,6 @@
   }
 #endif
 
-  /* If writing to memory or generating a set
-  ** only a single column may be output.
-  */
-#ifndef SQLITE_OMIT_SUBQUERY
-  if( checkForMultiColumnSelectError(pParse, pDest, pEList->nExpr) ){
-    goto select_end;
-  }
-#endif
-
   /* If possible, rewrite the query to use GROUP BY instead of DISTINCT.
   ** GROUP BY might use an index, DISTINCT never does.
   */
@@ -89242,6 +91010,7 @@
     pKeyInfo = keyInfoFromExprList(pParse, p->pEList);
     sqlite3VdbeAddOp4(v, OP_OpenEphemeral, distinct, 0, 0,
                         (char*)pKeyInfo, P4_KEYINFO_HANDOFF);
+    sqlite3VdbeChangeP5(v, BTREE_UNORDERED);
   }else{
     distinct = -1;
   }
@@ -90782,6 +92551,7 @@
   int iEndTrigger = 0;        /* Label to jump to if WHEN is false */
 
   assert( pTrigger->zName==0 || pTab==tableOfTrigger(pTrigger) );
+  assert( pTop->pVdbe );
 
   /* Allocate the TriggerPrg and SubProgram objects. To ensure that they
   ** are freed if an error occurs, link them into the Parse.pTriggerPrg 
@@ -90792,7 +92562,7 @@
   pTop->pTriggerPrg = pPrg;
   pPrg->pProgram = pProgram = sqlite3DbMallocZero(db, sizeof(SubProgram));
   if( !pProgram ) return 0;
-  pProgram->nRef = 1;
+  sqlite3VdbeLinkSubProgram(pTop->pVdbe, pProgram);
   pPrg->pTrigger = pTrigger;
   pPrg->orconf = orconf;
   pPrg->aColmask[0] = 0xffffffff;
@@ -90926,8 +92696,9 @@
   /* Code the OP_Program opcode in the parent VDBE. P4 of the OP_Program 
   ** is a pointer to the sub-vdbe containing the trigger program.  */
   if( pPrg ){
+    int bRecursive = (p->zName && 0==(pParse->db->flags&SQLITE_RecTriggers));
+
     sqlite3VdbeAddOp3(v, OP_Program, reg, ignoreJump, ++pParse->nMem);
-    pPrg->pProgram->nRef++;
     sqlite3VdbeChangeP4(v, -1, (const char *)pPrg->pProgram, P4_SUBPROGRAM);
     VdbeComment(
         (v, "Call: %s.%s", (p->zName?p->zName:"fkey"), onErrorText(orconf)));
@@ -90937,7 +92708,7 @@
     ** invocation is disallowed if (a) the sub-program is really a trigger,
     ** not a foreign key action, and (b) the flag to enable recursive triggers
     ** is clear.  */
-    sqlite3VdbeChangeP5(v, (u8)(p->zName && !(pParse->db->flags&SQLITE_RecTriggers)));
+    sqlite3VdbeChangeP5(v, (u8)bRecursive);
   }
 }
 
@@ -91086,7 +92857,7 @@
 **    May you find forgiveness for yourself and forgive others.
 **    May you share freely, never taking more than you give.
 **
-sqlite*************************************************************************
+*************************************************************************
 ** This file contains C code routines that are called by the parser
 ** to handle UPDATE statements.
 */
@@ -91715,6 +93486,7 @@
   assert( v );
   ephemTab = pParse->nTab++;
   sqlite3VdbeAddOp2(v, OP_OpenEphemeral, ephemTab, pTab->nCol+1+(pRowid!=0));
+  sqlite3VdbeChangeP5(v, BTREE_UNORDERED);
 
   /* fill the ephemeral table 
   */
@@ -91854,6 +93626,10 @@
     sqlite3SetString(pzErrMsg, db, "cannot VACUUM from within a transaction");
     return SQLITE_ERROR;
   }
+  if( db->activeVdbeCnt>1 ){
+    sqlite3SetString(pzErrMsg, db,"cannot VACUUM - SQL statements in progress");
+    return SQLITE_ERROR;
+  }
 
   /* Save the current value of the database flags so that it can be 
   ** restored before returning. Then set the writable-schema flag, and
@@ -92305,14 +94081,14 @@
 ** in the list are moved to the sqlite3.pDisconnect list of the associated 
 ** database connection.
 */
-SQLITE_PRIVATE void sqlite3VtabClear(Table *p){
-  vtabDisconnectAll(0, p);
+SQLITE_PRIVATE void sqlite3VtabClear(sqlite3 *db, Table *p){
+  if( !db || db->pnBytesFreed==0 ) vtabDisconnectAll(0, p);
   if( p->azModuleArg ){
     int i;
     for(i=0; i<p->nModuleArg; i++){
-      sqlite3DbFree(p->dbMem, p->azModuleArg[i]);
+      sqlite3DbFree(db, p->azModuleArg[i]);
     }
-    sqlite3DbFree(p->dbMem, p->azModuleArg);
+    sqlite3DbFree(db, p->azModuleArg);
   }
 }
 
@@ -92477,7 +94253,6 @@
       assert( pTab==pOld );  /* Malloc must have failed inside HashInsert() */
       return;
     }
-    pSchema->db = pParse->db;
     pParse->pNewTable = 0;
   }
 }
@@ -92551,7 +94326,7 @@
       *pzErr = sqlite3MPrintf(db, "vtable constructor failed: %s", zModuleName);
     }else {
       *pzErr = sqlite3MPrintf(db, "%s", zErr);
-      sqlite3DbFree(db, zErr);
+      sqlite3_free(zErr);
     }
     sqlite3DbFree(db, pVTable);
   }else if( ALWAYS(pVTable->pVtab) ){
@@ -92766,7 +94541,7 @@
     if( pParse->pVdbe ){
       sqlite3VdbeFinalize(pParse->pVdbe);
     }
-    sqlite3DeleteTable(pParse->pNewTable);
+    sqlite3DeleteTable(db, pParse->pNewTable);
     sqlite3StackFree(db, pParse);
   }
 
@@ -92853,8 +94628,8 @@
     if( pVtab && (x = pVtab->pModule->xSync)!=0 ){
       rc = x(pVtab);
       sqlite3DbFree(db, *pzErrmsg);
-      *pzErrmsg = pVtab->zErrMsg;
-      pVtab->zErrMsg = 0;
+      *pzErrmsg = sqlite3DbStrDup(db, pVtab->zErrMsg);
+      sqlite3_free(pVtab->zErrMsg);
     }
   }
   db->aVTrans = aVTrans;
@@ -93354,6 +95129,7 @@
 static int whereClauseInsert(WhereClause *pWC, Expr *p, u8 wtFlags){
   WhereTerm *pTerm;
   int idx;
+  testcase( wtFlags & TERM_VIRTUAL );  /* EV: R-00211-15100 */
   if( pWC->nTerm>=pWC->nSlot ){
     WhereTerm *pOld = pWC->a;
     sqlite3 *db = pWC->pParse->db;
@@ -93499,6 +95275,13 @@
 ** Return TRUE if the given operator is one of the operators that is
 ** allowed for an indexable WHERE clause term.  The allowed operators are
 ** "=", "<", ">", "<=", ">=", and "IN".
+**
+** IMPLEMENTATION-OF: R-59926-26393 To be usable by an index a term must be
+** of one of the following forms: column = expression column > expression
+** column >= expression column < expression column <= expression
+** expression = column expression > column expression >= column
+** expression < column expression <= column column IN
+** (expression-list) column IN (subquery) column IS NULL
 */
 static int allowedOp(int op){
   assert( TK_GT>TK_EQ && TK_GT<TK_GE );
@@ -93662,7 +95445,6 @@
   int c;                     /* One character in z[] */
   int cnt;                   /* Number of non-wildcard prefix characters */
   char wc[3];                /* Wildcard characters */
-  CollSeq *pColl;            /* Collating sequence for LHS */
   sqlite3 *db = pParse->db;  /* Database connection */
   sqlite3_value *pVal = 0;
   int op;                    /* Opcode of pRight */
@@ -93681,19 +95463,6 @@
     return 0;
   }
   assert( pLeft->iColumn!=(-1) ); /* Because IPK never has AFF_TEXT */
-  pColl = sqlite3ExprCollSeq(pParse, pLeft);
-  if( pColl==0 ) return 0;  /* Happens when LHS has an undefined collation */
-  if( (pColl->type!=SQLITE_COLL_BINARY || *pnoCase) &&
-      (pColl->type!=SQLITE_COLL_NOCASE || !*pnoCase) ){
-    /* IMP: R-09003-32046 For the GLOB operator, the column must use the
-    ** default BINARY collating sequence.
-    ** IMP: R-41408-28306 For the LIKE operator, if case_sensitive_like mode
-    ** is enabled then the column must use the default BINARY collating
-    ** sequence, or if case_sensitive_like mode is disabled then the column
-    ** must use the built-in NOCASE collating sequence.
-    */
-    return 0;
-  }
 
   pRight = pList->a[0].pExpr;
   op = pRight->op;
@@ -93702,11 +95471,12 @@
   }
   if( op==TK_VARIABLE ){
     Vdbe *pReprepare = pParse->pReprepare;
-    pVal = sqlite3VdbeGetValue(pReprepare, pRight->iColumn, SQLITE_AFF_NONE);
+    int iCol = pRight->iColumn;
+    pVal = sqlite3VdbeGetValue(pReprepare, iCol, SQLITE_AFF_NONE);
     if( pVal && sqlite3_value_type(pVal)==SQLITE_TEXT ){
       z = (char *)sqlite3_value_text(pVal);
     }
-    sqlite3VdbeSetVarmask(pParse->pVdbe, pRight->iColumn);
+    sqlite3VdbeSetVarmask(pParse->pVdbe, iCol); /* IMP: R-23257-02778 */
     assert( pRight->op==TK_VARIABLE || pRight->op==TK_REGISTER );
   }else if( op==TK_STRING ){
     z = pRight->u.zToken;
@@ -93716,15 +95486,15 @@
     while( (c=z[cnt])!=0 && c!=wc[0] && c!=wc[1] && c!=wc[2] ){
       cnt++;
     }
-    if( cnt!=0 && c!=0 && 255!=(u8)z[cnt-1] ){
+    if( cnt!=0 && 255!=(u8)z[cnt-1] ){
       Expr *pPrefix;
-      *pisComplete = z[cnt]==wc[0] && z[cnt+1]==0;
+      *pisComplete = c==wc[0] && z[cnt+1]==0;
       pPrefix = sqlite3Expr(db, TK_STRING, z);
       if( pPrefix ) pPrefix->u.zToken[cnt] = 0;
       *ppPrefix = pPrefix;
       if( op==TK_VARIABLE ){
         Vdbe *v = pParse->pVdbe;
-        sqlite3VdbeSetVarmask(v, pRight->iColumn);
+        sqlite3VdbeSetVarmask(v, pRight->iColumn); /* IMP: R-23257-02778 */
         if( *pisComplete && pRight->u.zToken[1] ){
           /* If the rhs of the LIKE expression is a variable, and the current
           ** value of the variable means there is no need to invoke the LIKE
@@ -94057,6 +95827,8 @@
     /* At this point, okToChngToIN is true if original pTerm satisfies
     ** case 1.  In that case, construct a new virtual term that is 
     ** pTerm converted into an IN operator.
+    **
+    ** EV: R-00211-15100
     */
     if( okToChngToIN ){
       Expr *pDup;            /* A transient duplicate expression */
@@ -94273,6 +96045,7 @@
     Expr *pNewExpr2;
     int idxNew1;
     int idxNew2;
+    CollSeq *pColl;    /* Collating sequence to use */
 
     pLeft = pExpr->x.pList->a[1].pExpr;
     pStr2 = sqlite3ExprDup(db, pStr1, 0);
@@ -94287,17 +96060,23 @@
         ** inequality.  To avoid this, make sure to also run the full
         ** LIKE on all candidate expressions by clearing the isComplete flag
         */
-        if( c=='A'-1 ) isComplete = 0;
+        if( c=='A'-1 ) isComplete = 0;   /* EV: R-64339-08207 */
+
 
         c = sqlite3UpperToLower[c];
       }
       *pC = c + 1;
     }
-    pNewExpr1 = sqlite3PExpr(pParse, TK_GE, sqlite3ExprDup(db,pLeft,0),pStr1,0);
+    pColl = sqlite3FindCollSeq(db, SQLITE_UTF8, noCase ? "NOCASE" : "BINARY",0);
+    pNewExpr1 = sqlite3PExpr(pParse, TK_GE, 
+                     sqlite3ExprSetColl(sqlite3ExprDup(db,pLeft,0), pColl),
+                     pStr1, 0);
     idxNew1 = whereClauseInsert(pWC, pNewExpr1, TERM_VIRTUAL|TERM_DYNAMIC);
     testcase( idxNew1==0 );
     exprAnalyze(pSrc, pWC, idxNew1);
-    pNewExpr2 = sqlite3PExpr(pParse, TK_LT, sqlite3ExprDup(db,pLeft,0),pStr2,0);
+    pNewExpr2 = sqlite3PExpr(pParse, TK_LT,
+                     sqlite3ExprSetColl(sqlite3ExprDup(db,pLeft,0), pColl),
+                     pStr2, 0);
     idxNew2 = whereClauseInsert(pWC, pNewExpr2, TERM_VIRTUAL|TERM_DYNAMIC);
     testcase( idxNew2==0 );
     exprAnalyze(pSrc, pWC, idxNew2);
@@ -94729,7 +96508,7 @@
 
   assert( pParse->nQueryLoop >= (double)1 );
   pTable = pSrc->pTab;
-  nTableRow = pTable->pIndex ? pTable->pIndex->aiRowEst[0] : 1000000;
+  nTableRow = pTable->nRowEst;
   logN = estLog(nTableRow);
   costTempIdx = 2*logN*(nTableRow/pParse->nQueryLoop + 1);
   if( costTempIdx>=pCost->rCost ){
@@ -95049,7 +96828,7 @@
       sqlite3ErrorMsg(pParse, "%s", pVtab->zErrMsg);
     }
   }
-  sqlite3DbFree(pParse->db, pVtab->zErrMsg);
+  sqlite3_free(pVtab->zErrMsg);
   pVtab->zErrMsg = 0;
 
   for(i=0; i<p->nConstraint; i++){
@@ -95339,7 +97118,7 @@
   assert( pExpr->op!=TK_VARIABLE );
   if( pExpr->op==TK_REGISTER && pExpr->op2==TK_VARIABLE ){
     int iVar = pExpr->iColumn;
-    sqlite3VdbeSetVarmask(pParse->pVdbe, iVar);
+    sqlite3VdbeSetVarmask(pParse->pVdbe, iVar); /* IMP: R-23257-02778 */
     *pp = sqlite3VdbeGetValue(pParse->pReprepare, iVar, aff);
     return SQLITE_OK;
   }
@@ -95536,23 +97315,14 @@
     sPk.nColumn = 1;
     sPk.aiColumn = &aiColumnPk;
     sPk.aiRowEst = aiRowEstPk;
-    aiRowEstPk[1] = 1;
     sPk.onError = OE_Replace;
     sPk.pTable = pSrc->pTab;
+    aiRowEstPk[0] = pSrc->pTab->nRowEst;
+    aiRowEstPk[1] = 1;
     pFirst = pSrc->pTab->pIndex;
     if( pSrc->notIndexed==0 ){
       sPk.pNext = pFirst;
     }
-    /* The aiRowEstPk[0] is an estimate of the total number of rows in the
-    ** table.  Get this information from the ANALYZE information if it is
-    ** available.  If not available, assume the table 1 million rows in size.
-    */
-    if( pFirst ){
-      assert( pFirst->aiRowEst!=0 ); /* Allocated together with pFirst */
-      aiRowEstPk[0] = pFirst->aiRowEst[0];
-    }else{
-      aiRowEstPk[0] = 1000000;
-    }
     pProbe = &sPk;
     wsFlagMask = ~(
         WHERE_COLUMN_IN|WHERE_COLUMN_EQ|WHERE_COLUMN_NULL|WHERE_COLUMN_RANGE
@@ -95649,7 +97419,7 @@
         if( ExprHasProperty(pExpr, EP_xIsSelect) ){
           nInMul *= 25;
           bInEst = 1;
-        }else if( pExpr->x.pList ){
+        }else if( ALWAYS(pExpr->x.pList) ){
           nInMul *= pExpr->x.pList->nExpr + 1;
         }
       }else if( pTerm->eOperator & WO_ISNULL ){
@@ -95914,6 +97684,9 @@
 ** in the ON clause.  The term is disabled in (3) because it is not part
 ** of a LEFT OUTER JOIN.  In (1), the term is not disabled.
 **
+** IMPLEMENTATION-OF: R-24597-58655 No tests are done for terms that are
+** completely satisfied by indices.
+**
 ** Disabling a term causes that term to not be tested in the inner loop
 ** of the join.  Disabling is an optimization.  When terms are satisfied
 ** by indices, we disable them to prevent redundant tests in the inner
@@ -96125,6 +97898,7 @@
     /* The following true for indices with redundant columns. 
     ** Ex: CREATE INDEX i1 ON t1(a,b,a); SELECT * FROM t1 WHERE a=0 AND b=0; */
     testcase( (pTerm->wtFlags & TERM_CODED)!=0 );
+    testcase( pTerm->wtFlags & TERM_VIRTUAL ); /* EV: R-30575-11662 */
     r1 = codeEqualityTerm(pParse, pTerm, pLevel, regBase+j);
     if( r1!=regBase+j ){
       if( nReg==1 ){
@@ -96268,6 +98042,7 @@
     assert( pTerm->pExpr!=0 );
     assert( pTerm->leftCursor==iCur );
     assert( omitTable==0 );
+    testcase( pTerm->wtFlags & TERM_VIRTUAL ); /* EV: R-30575-11662 */
     iRowidReg = codeEqualityTerm(pParse, pTerm, pLevel, iReleaseReg);
     addrNxt = pLevel->addrNxt;
     sqlite3VdbeAddOp2(v, OP_MustBeInt, iRowidReg, addrNxt);
@@ -96308,6 +98083,7 @@
       assert( TK_LT==TK_GT+2 );      /*  ... of the TK_xx values... */
       assert( TK_GE==TK_GT+3 );      /*  ... is correcct. */
 
+      testcase( pStart->wtFlags & TERM_VIRTUAL ); /* EV: R-30575-11662 */
       pX = pStart->pExpr;
       assert( pX!=0 );
       assert( pStart->leftCursor==iCur );
@@ -96325,6 +98101,7 @@
       pX = pEnd->pExpr;
       assert( pX!=0 );
       assert( pEnd->leftCursor==iCur );
+      testcase( pEnd->wtFlags & TERM_VIRTUAL ); /* EV: R-30575-11662 */
       memEndValue = ++pParse->nMem;
       sqlite3ExprCode(pParse, pX->pRight, memEndValue);
       if( pX->op==TK_LT || pX->op==TK_GT ){
@@ -96382,7 +98159,7 @@
     **         constraints but an index is selected anyway, in order
     **         to force the output order to conform to an ORDER BY.
     */  
-    int aStartOp[] = {
+    static const u8 aStartOp[] = {
       0,
       0,
       OP_Rewind,           /* 2: (!start_constraints && startEq &&  !bRev) */
@@ -96392,12 +98169,12 @@
       OP_SeekGe,           /* 6: (start_constraints  &&  startEq && !bRev) */
       OP_SeekLe            /* 7: (start_constraints  &&  startEq &&  bRev) */
     };
-    int aEndOp[] = {
+    static const u8 aEndOp[] = {
       OP_Noop,             /* 0: (!end_constraints) */
       OP_IdxGE,            /* 1: (end_constraints && !bRev) */
       OP_IdxLT             /* 2: (end_constraints && bRev) */
     };
-    int nEq = pLevel->plan.nEq;
+    int nEq = pLevel->plan.nEq;  /* Number of == or IN terms */
     int isMinQuery = 0;          /* If this is an optimized SELECT min(x).. */
     int regBase;                 /* Base register holding constraint values */
     int r1;                      /* Temp register */
@@ -96407,10 +98184,10 @@
     int endEq;                   /* True if range end uses ==, >= or <= */
     int start_constraints;       /* Start of range is constrained */
     int nConstraint;             /* Number of constraint terms */
-    Index *pIdx;         /* The index we will be using */
-    int iIdxCur;         /* The VDBE cursor for the index */
-    int nExtraReg = 0;   /* Number of extra registers needed */
-    int op;              /* Instruction opcode */
+    Index *pIdx;                 /* The index we will be using */
+    int iIdxCur;                 /* The VDBE cursor for the index */
+    int nExtraReg = 0;           /* Number of extra registers needed */
+    int op;                      /* Instruction opcode */
     char *zStartAff;             /* Affinity for start of range constraint */
     char *zEndAff;               /* Affinity for end of range constraint */
 
@@ -96492,6 +98269,7 @@
         }
       }  
       nConstraint++;
+      testcase( pRangeStart->wtFlags & TERM_VIRTUAL ); /* EV: R-30575-11662 */
     }else if( isMinQuery ){
       sqlite3VdbeAddOp2(v, OP_Null, 0, regBase+nEq);
       nConstraint++;
@@ -96531,6 +98309,7 @@
       }  
       codeApplyAffinity(pParse, regBase, nEq+1, zEndAff);
       nConstraint++;
+      testcase( pRangeEnd->wtFlags & TERM_VIRTUAL ); /* EV: R-30575-11662 */
     }
     sqlite3DbFree(pParse->db, zStartAff);
     sqlite3DbFree(pParse->db, zEndAff);
@@ -96737,11 +98516,15 @@
 
   /* Insert code to test every subexpression that can be completely
   ** computed using the current set of tables.
+  **
+  ** IMPLEMENTATION-OF: R-49525-50935 Terms that cannot be satisfied through
+  ** the use of indices become tests that are evaluated against each row of
+  ** the relevant input tables.
   */
   k = 0;
   for(pTerm=pWC->a, j=pWC->nTerm; j>0; j--, pTerm++){
     Expr *pE;
-    testcase( pTerm->wtFlags & TERM_VIRTUAL );
+    testcase( pTerm->wtFlags & TERM_VIRTUAL ); /* IMP: R-30575-11662 */
     testcase( pTerm->wtFlags & TERM_CODED );
     if( pTerm->wtFlags & (TERM_VIRTUAL|TERM_CODED) ) continue;
     if( (pTerm->prereqAll & notReady)!=0 ){
@@ -96769,7 +98552,7 @@
     VdbeComment((v, "record LEFT JOIN hit"));
     sqlite3ExprCacheClear(pParse);
     for(pTerm=pWC->a, j=0; j<pWC->nTerm; j++, pTerm++){
-      testcase( pTerm->wtFlags & TERM_VIRTUAL );
+      testcase( pTerm->wtFlags & TERM_VIRTUAL );  /* IMP: R-30575-11662 */
       testcase( pTerm->wtFlags & TERM_CODED );
       if( pTerm->wtFlags & (TERM_VIRTUAL|TERM_CODED) ) continue;
       if( (pTerm->prereqAll & notReady)!=0 ){
@@ -96987,7 +98770,7 @@
   initMaskSet(pMaskSet);
   whereClauseInit(pWC, pParse, pMaskSet);
   sqlite3ExprCodeConstants(pParse, pWhere);
-  whereSplit(pWC, pWhere, TK_AND);
+  whereSplit(pWC, pWhere, TK_AND);   /* IMP: R-15842-53296 */
     
   /* Special case: a WHERE clause that is constant.  Evaluate the
   ** expression and either jump over all of the code or fall thru.
@@ -97075,6 +98858,8 @@
     int bestJ = -1;             /* The value of j */
     Bitmask m;                  /* Bitmask value for j or bestJ */
     int isOptimal;              /* Iterator for optimal/non-optimal search */
+    int nUnconstrained;         /* Number tables without INDEXED BY */
+    Bitmask notIndexed;         /* Mask of tables that cannot use an index */
 
     memset(&bestPlan, 0, sizeof(bestPlan));
     bestPlan.rCost = SQLITE_BIG_DBL;
@@ -97111,13 +98896,15 @@
     **
     ** The best strategy is to iterate through table t1 first. However it
     ** is not possible to determine this with a simple greedy algorithm.
-    ** However, since the cost of a linear scan through table t2 is the same 
+    ** Since the cost of a linear scan through table t2 is the same 
     ** as the cost of a linear scan through table t1, a simple greedy 
     ** algorithm may choose to use t2 for the outer loop, which is a much
     ** costlier approach.
     */
+    nUnconstrained = 0;
+    notIndexed = 0;
     for(isOptimal=(iFrom<nTabList-1); isOptimal>=0; isOptimal--){
-      Bitmask mask;  /* Mask of tables not yet ready */
+      Bitmask mask;             /* Mask of tables not yet ready */
       for(j=iFrom, pTabItem=&pTabList->a[j]; j<nTabList; j++, pTabItem++){
         int doNotReorder;    /* True if this table should not be reordered */
         WhereCost sCost;     /* Cost information from best[Virtual]Index() */
@@ -97132,6 +98919,7 @@
         }
         mask = (isOptimal ? m : notReady);
         pOrderBy = ((i==0 && ppOrderBy )?*ppOrderBy:0);
+        if( pTabItem->pIndex==0 ) nUnconstrained++;
   
         assert( pTabItem->pTab );
 #ifndef SQLITE_OMIT_VIRTUALTABLE
@@ -97145,9 +98933,43 @@
         }
         assert( isOptimal || (sCost.used&notReady)==0 );
 
-        if( (sCost.used&notReady)==0
-         && (bestJ<0 || sCost.rCost<bestPlan.rCost
-             || (sCost.rCost<=bestPlan.rCost && sCost.nRow<bestPlan.nRow))
+        /* If an INDEXED BY clause is present, then the plan must use that
+        ** index if it uses any index at all */
+        assert( pTabItem->pIndex==0 
+                  || (sCost.plan.wsFlags & WHERE_NOT_FULLSCAN)==0
+                  || sCost.plan.u.pIdx==pTabItem->pIndex );
+
+        if( isOptimal && (sCost.plan.wsFlags & WHERE_NOT_FULLSCAN)==0 ){
+          notIndexed |= m;
+        }
+
+        /* Conditions under which this table becomes the best so far:
+        **
+        **   (1) The table must not depend on other tables that have not
+        **       yet run.
+        **
+        **   (2) A full-table-scan plan cannot supercede another plan unless
+        **       it is an "optimal" plan as defined above.
+        **
+        **   (3) All tables have an INDEXED BY clause or this table lacks an
+        **       INDEXED BY clause or this table uses the specific
+        **       index specified by its INDEXED BY clause.  This rule ensures
+        **       that a best-so-far is always selected even if an impossible
+        **       combination of INDEXED BY clauses are given.  The error
+        **       will be detected and relayed back to the application later.
+        **       The NEVER() comes about because rule (2) above prevents
+        **       An indexable full-table-scan from reaching rule (3).
+        **
+        **   (4) The plan cost must be lower than prior plans or else the
+        **       cost must be the same and the number of rows must be lower.
+        */
+        if( (sCost.used&notReady)==0                       /* (1) */
+            && (bestJ<0 || (notIndexed&m)!=0               /* (2) */
+                || (sCost.plan.wsFlags & WHERE_NOT_FULLSCAN)!=0)
+            && (nUnconstrained==0 || pTabItem->pIndex==0   /* (3) */
+                || NEVER((sCost.plan.wsFlags & WHERE_NOT_FULLSCAN)!=0))
+            && (bestJ<0 || sCost.rCost<bestPlan.rCost      /* (4) */
+                || (sCost.rCost<=bestPlan.rCost && sCost.nRow<bestPlan.nRow))
         ){
           WHERETRACE(("... best so far with cost=%g and nRow=%g\n",
                       sCost.rCost, sCost.nRow));
@@ -97693,26 +99515,26 @@
 **                       defined, then do no error processing.
 */
 #define YYCODETYPE unsigned char
-#define YYNOCODE 254
+#define YYNOCODE 253
 #define YYACTIONTYPE unsigned short int
 #define YYWILDCARD 67
 #define sqlite3ParserTOKENTYPE Token
 typedef union {
   int yyinit;
   sqlite3ParserTOKENTYPE yy0;
-  Select* yy3;
-  ExprList* yy14;
-  SrcList* yy65;
-  struct LikeOp yy96;
-  Expr* yy132;
-  u8 yy186;
-  int yy328;
-  ExprSpan yy346;
-  struct TrigEvent yy378;
-  IdList* yy408;
-  struct {int value; int mask;} yy429;
-  TriggerStep* yy473;
-  struct LimitVal yy476;
+  int yy4;
+  struct TrigEvent yy90;
+  ExprSpan yy118;
+  TriggerStep* yy203;
+  u8 yy210;
+  struct {int value; int mask;} yy215;
+  SrcList* yy259;
+  struct LimitVal yy292;
+  Expr* yy314;
+  ExprList* yy322;
+  struct LikeOp yy342;
+  IdList* yy384;
+  Select* yy387;
 } YYMINORTYPE;
 #ifndef YYSTACKDEPTH
 #define YYSTACKDEPTH 100
@@ -97721,8 +99543,8 @@
 #define sqlite3ParserARG_PDECL ,Parse *pParse
 #define sqlite3ParserARG_FETCH Parse *pParse = yypParser->pParse
 #define sqlite3ParserARG_STORE yypParser->pParse = pParse
-#define YYNSTATE 631
-#define YYNRULE 330
+#define YYNSTATE 630
+#define YYNRULE 329
 #define YYFALLBACK 1
 #define YY_NO_ACTION      (YYNSTATE+YYNRULE+2)
 #define YY_ACCEPT_ACTION  (YYNSTATE+YYNRULE+1)
@@ -97792,472 +99614,473 @@
 **                     shifting non-terminals after a reduce.
 **  yy_default[]       Default action for each state.
 */
-#define YY_ACTTAB_COUNT (1550)
+#define YY_ACTTAB_COUNT (1557)
 static const YYACTIONTYPE yy_action[] = {
- /*     0 */   313,   49,  556,   46,  147,  172,  628,  598,   55,   55,
- /*    10 */    55,   55,  302,   53,   53,   53,   53,   52,   52,   51,
- /*    20 */    51,   51,   50,  238,  603,   66,  624,  623,  604,  598,
- /*    30 */   591,  585,   48,   53,   53,   53,   53,   52,   52,   51,
- /*    40 */    51,   51,   50,  238,   51,   51,   51,   50,  238,   56,
- /*    50 */    57,   47,  583,  582,  584,  584,   54,   54,   55,   55,
- /*    60 */    55,   55,  609,   53,   53,   53,   53,   52,   52,   51,
- /*    70 */    51,   51,   50,  238,  313,  598,  672,  330,  411,  217,
+ /*     0 */   313,  960,  186,  419,    2,  172,  627,  597,   55,   55,
+ /*    10 */    55,   55,   48,   53,   53,   53,   53,   52,   52,   51,
+ /*    20 */    51,   51,   50,  238,  302,  283,  623,  622,  516,  515,
+ /*    30 */   590,  584,   55,   55,   55,   55,  282,   53,   53,   53,
+ /*    40 */    53,   52,   52,   51,   51,   51,   50,  238,    6,   56,
+ /*    50 */    57,   47,  582,  581,  583,  583,   54,   54,   55,   55,
+ /*    60 */    55,   55,  608,   53,   53,   53,   53,   52,   52,   51,
+ /*    70 */    51,   51,   50,  238,  313,  597,  409,  330,  579,  579,
  /*    80 */    32,   53,   53,   53,   53,   52,   52,   51,   51,   51,
- /*    90 */    50,  238,  330,  414,  621,  620,  166,  598,  673,  382,
- /*   100 */   379,  378,  602,   73,  591,  585,  307,  424,  166,   58,
- /*   110 */   377,  382,  379,  378,  516,  515,  624,  623,  254,  200,
- /*   120 */   199,  198,  377,   56,   57,   47,  583,  582,  584,  584,
- /*   130 */    54,   54,   55,   55,   55,   55,  581,   53,   53,   53,
- /*   140 */    53,   52,   52,   51,   51,   51,   50,  238,  313,  270,
- /*   150 */   226,  422,  283,  133,  177,  139,  284,  385,  279,  384,
- /*   160 */   169,  197,  251,  282,  253,  226,  411,  275,  440,  167,
- /*   170 */   139,  284,  385,  279,  384,  169,  571,  236,  591,  585,
- /*   180 */   240,  414,  275,  622,  621,  620,  674,  437,  441,  442,
- /*   190 */   602,   88,  352,  266,  439,  268,  438,   56,   57,   47,
- /*   200 */   583,  582,  584,  584,   54,   54,   55,   55,   55,   55,
+ /*    90 */    50,  238,  330,  217,  620,  619,  166,  411,  624,  382,
+ /*   100 */   379,  378,    7,  491,  590,  584,  200,  199,  198,   58,
+ /*   110 */   377,  300,  414,  621,  481,   66,  623,  622,  621,  580,
+ /*   120 */   254,  601,   94,   56,   57,   47,  582,  581,  583,  583,
+ /*   130 */    54,   54,   55,   55,   55,   55,  671,   53,   53,   53,
+ /*   140 */    53,   52,   52,   51,   51,   51,   50,  238,  313,  532,
+ /*   150 */   226,  506,  507,  133,  177,  139,  284,  385,  279,  384,
+ /*   160 */   169,  197,  342,  398,  251,  226,  253,  275,  388,  167,
+ /*   170 */   139,  284,  385,  279,  384,  169,  570,  236,  590,  584,
+ /*   180 */   672,  240,  275,  157,  620,  619,  554,  437,   51,   51,
+ /*   190 */    51,   50,  238,  343,  439,  553,  438,   56,   57,   47,
+ /*   200 */   582,  581,  583,  583,   54,   54,   55,   55,   55,   55,
  /*   210 */   465,   53,   53,   53,   53,   52,   52,   51,   51,   51,
- /*   220 */    50,  238,  313,  471,   52,   52,   51,   51,   51,   50,
- /*   230 */   238,  234,  166,  491,  567,  382,  379,  378,    1,  440,
- /*   240 */   252,  176,  624,  623,  608,   67,  377,  513,  622,  443,
- /*   250 */   237,  577,  591,  585,  622,  172,  466,  598,  554,  441,
- /*   260 */   340,  409,  526,  580,  580,  349,  596,  553,  194,  482,
- /*   270 */   175,   56,   57,   47,  583,  582,  584,  584,   54,   54,
- /*   280 */    55,   55,   55,   55,  562,   53,   53,   53,   53,   52,
- /*   290 */    52,   51,   51,   51,   50,  238,  313,  594,  594,  594,
- /*   300 */   561,  578,  469,   65,  259,  351,  258,  411,  624,  623,
- /*   310 */   621,  620,  332,  576,  575,  240,  560,  568,  520,  411,
- /*   320 */   341,  237,  414,  624,  623,  598,  591,  585,  542,  519,
- /*   330 */   171,  602,   95,   68,  414,  624,  623,  624,  623,   38,
- /*   340 */   877,  506,  507,  602,   88,   56,   57,   47,  583,  582,
- /*   350 */   584,  584,   54,   54,   55,   55,   55,   55,  532,   53,
+ /*   220 */    50,  238,  313,  390,   52,   52,   51,   51,   51,   50,
+ /*   230 */   238,  391,  166,  491,  566,  382,  379,  378,  409,  440,
+ /*   240 */   579,  579,  252,  440,  607,   66,  377,  513,  621,   49,
+ /*   250 */    46,  147,  590,  584,  621,   16,  466,  189,  621,  441,
+ /*   260 */   442,  673,  526,  441,  340,  577,  595,   64,  194,  482,
+ /*   270 */   434,   56,   57,   47,  582,  581,  583,  583,   54,   54,
+ /*   280 */    55,   55,   55,   55,   30,   53,   53,   53,   53,   52,
+ /*   290 */    52,   51,   51,   51,   50,  238,  313,  593,  593,  593,
+ /*   300 */   387,  578,  606,  493,  259,  351,  258,  411,    1,  623,
+ /*   310 */   622,  496,  623,  622,   65,  240,  623,  622,  597,  443,
+ /*   320 */   237,  239,  414,  341,  237,  602,  590,  584,   18,  603,
+ /*   330 */   166,  601,   87,  382,  379,  378,   67,  623,  622,   38,
+ /*   340 */   623,  622,  176,  270,  377,   56,   57,   47,  582,  581,
+ /*   350 */   583,  583,   54,   54,   55,   55,   55,   55,  175,   53,
  /*   360 */    53,   53,   53,   52,   52,   51,   51,   51,   50,  238,
- /*   370 */   313,  411,  579,  398,  531,  237,  621,  620,  388,  625,
- /*   380 */   500,  206,  167,  396,  233,  312,  414,  387,  569,  492,
- /*   390 */   216,  621,  620,  566,  622,  602,   74,  533,  210,  491,
- /*   400 */   591,  585,  548,  621,  620,  621,  620,  300,  598,  466,
- /*   410 */   481,   67,  603,   35,  622,  601,  604,  547,    6,   56,
- /*   420 */    57,   47,  583,  582,  584,  584,   54,   54,   55,   55,
- /*   430 */    55,   55,  601,   53,   53,   53,   53,   52,   52,   51,
- /*   440 */    51,   51,   50,  238,  313,  411,  184,  409,  528,  580,
- /*   450 */   580,  551,  962,  186,  419,    2,  353,  259,  351,  258,
- /*   460 */   414,  409,  411,  580,  580,   44,  411,  544,  240,  602,
- /*   470 */    94,  190,    7,   62,  591,  585,  598,  414,  350,  607,
- /*   480 */   493,  414,  409,  317,  580,  580,  602,   95,  496,  565,
- /*   490 */   602,   80,  203,   56,   57,   47,  583,  582,  584,  584,
- /*   500 */    54,   54,   55,   55,   55,   55,  535,   53,   53,   53,
- /*   510 */    53,   52,   52,   51,   51,   51,   50,  238,  313,  202,
- /*   520 */   564,  293,  511,   49,  562,   46,  147,  411,  394,  183,
- /*   530 */   563,  549,  505,  549,  174,  409,  322,  580,  580,   39,
- /*   540 */   561,   37,  414,  624,  623,  192,  473,  383,  591,  585,
- /*   550 */   474,  602,   80,  601,  504,  544,  560,  364,  402,  210,
- /*   560 */   421,  952,  361,  952,  365,  201,  144,   56,   57,   47,
- /*   570 */   583,  582,  584,  584,   54,   54,   55,   55,   55,   55,
- /*   580 */   559,   53,   53,   53,   53,   52,   52,   51,   51,   51,
- /*   590 */    50,  238,  313,  601,  232,  264,  272,  321,  374,  484,
- /*   600 */   510,  146,  342,  146,  328,  425,  485,  407,  576,  575,
- /*   610 */   622,  621,  620,   49,  168,   46,  147,  353,  546,  491,
- /*   620 */   204,  240,  591,  585,  421,  951,  549,  951,  549,  168,
- /*   630 */   429,   67,  390,  343,  622,  434,  307,  423,  338,  360,
- /*   640 */   391,   56,   57,   47,  583,  582,  584,  584,   54,   54,
- /*   650 */    55,   55,   55,   55,  601,   53,   53,   53,   53,   52,
- /*   660 */    52,   51,   51,   51,   50,  238,  313,   34,  318,  425,
- /*   670 */   237,   21,  359,  273,  411,  167,  411,  276,  411,  540,
- /*   680 */   411,  422,   13,  318,  619,  618,  617,  622,  275,  414,
- /*   690 */   336,  414,  622,  414,  622,  414,  591,  585,  602,   69,
- /*   700 */   602,   97,  602,  100,  602,   98,  631,  629,  334,  475,
- /*   710 */   475,  367,  319,  148,  327,   56,   57,   47,  583,  582,
- /*   720 */   584,  584,   54,   54,   55,   55,   55,   55,  411,   53,
+ /*   370 */   313,  396,  233,  411,  531,  565,  317,  620,  619,   44,
+ /*   380 */   620,  619,  240,  206,  620,  619,  597,  266,  414,  268,
+ /*   390 */   409,  597,  579,  579,  352,  184,  505,  601,   73,  533,
+ /*   400 */   590,  584,  466,  548,  190,  620,  619,  576,  620,  619,
+ /*   410 */   547,  383,  551,   35,  332,  575,  574,  600,  504,   56,
+ /*   420 */    57,   47,  582,  581,  583,  583,   54,   54,   55,   55,
+ /*   430 */    55,   55,  567,   53,   53,   53,   53,   52,   52,   51,
+ /*   440 */    51,   51,   50,  238,  313,  411,  561,  561,  528,  364,
+ /*   450 */   259,  351,  258,  183,  361,  549,  524,  374,  411,  597,
+ /*   460 */   414,  240,  560,  560,  409,  604,  579,  579,  328,  601,
+ /*   470 */    93,  623,  622,  414,  590,  584,  237,  564,  559,  559,
+ /*   480 */   520,  402,  601,   87,  409,  210,  579,  579,  168,  421,
+ /*   490 */   950,  519,  950,   56,   57,   47,  582,  581,  583,  583,
+ /*   500 */    54,   54,   55,   55,   55,   55,  192,   53,   53,   53,
+ /*   510 */    53,   52,   52,   51,   51,   51,   50,  238,  313,  600,
+ /*   520 */   293,  563,  511,  234,  357,  146,  475,  475,  367,  411,
+ /*   530 */   562,  411,  358,  542,  425,  171,  411,  215,  144,  620,
+ /*   540 */   619,  544,  318,  353,  414,  203,  414,  275,  590,  584,
+ /*   550 */   549,  414,  174,  601,   94,  601,   79,  558,  471,   61,
+ /*   560 */   601,   79,  421,  949,  350,  949,   34,   56,   57,   47,
+ /*   570 */   582,  581,  583,  583,   54,   54,   55,   55,   55,   55,
+ /*   580 */   535,   53,   53,   53,   53,   52,   52,   51,   51,   51,
+ /*   590 */    50,  238,  313,  307,  424,  394,  272,   49,   46,  147,
+ /*   600 */   349,  322,    4,  411,  491,  312,  321,  425,  568,  492,
+ /*   610 */   216,  264,  407,  575,  574,  429,   66,  549,  414,  621,
+ /*   620 */   540,  602,  590,  584,   13,  603,  621,  601,   72,   12,
+ /*   630 */   618,  617,  616,  202,  210,  621,  546,  469,  422,  319,
+ /*   640 */   148,   56,   57,   47,  582,  581,  583,  583,   54,   54,
+ /*   650 */    55,   55,   55,   55,  338,   53,   53,   53,   53,   52,
+ /*   660 */    52,   51,   51,   51,   50,  238,  313,  600,  600,  411,
+ /*   670 */    39,   21,   37,  170,  237,  875,  411,  572,  572,  201,
+ /*   680 */   144,  473,  538,  331,  414,  474,  143,  146,  630,  628,
+ /*   690 */   334,  414,  353,  601,   68,  168,  590,  584,  132,  365,
+ /*   700 */   601,   96,  307,  423,  530,  336,   49,   46,  147,  568,
+ /*   710 */   406,  216,  549,  360,  529,   56,   57,   47,  582,  581,
+ /*   720 */   583,  583,   54,   54,   55,   55,   55,   55,  411,   53,
  /*   730 */    53,   53,   53,   52,   52,   51,   51,   51,   50,  238,
- /*   740 */   313,  411,  331,  414,  411,   49,  276,   46,  147,  569,
- /*   750 */   406,  216,  602,  106,  573,  573,  414,  354,  524,  414,
- /*   760 */   411,  622,  411,  224,    4,  602,  104,  605,  602,  108,
- /*   770 */   591,  585,  622,   20,  375,  414,  167,  414,  215,  144,
- /*   780 */   470,  239,  167,  225,  602,  109,  602,  134,   18,   56,
- /*   790 */    57,   47,  583,  582,  584,  584,   54,   54,   55,   55,
+ /*   740 */   313,  411,  605,  414,  484,  510,  172,  422,  597,  318,
+ /*   750 */   496,  485,  601,   99,  411,  142,  414,  411,  231,  411,
+ /*   760 */   540,  411,  359,  629,    2,  601,   97,  426,  308,  414,
+ /*   770 */   590,  584,  414,   20,  414,  621,  414,  621,  601,  106,
+ /*   780 */   503,  601,  105,  601,  108,  601,  109,  204,   28,   56,
+ /*   790 */    57,   47,  582,  581,  583,  583,   54,   54,   55,   55,
  /*   800 */    55,   55,  411,   53,   53,   53,   53,   52,   52,   51,
- /*   810 */    51,   51,   50,  238,  313,  411,  276,  414,   12,  459,
- /*   820 */   276,  171,  411,   16,  223,  189,  602,  135,  354,  170,
- /*   830 */   414,  622,  630,    2,  411,  622,  540,  414,  143,  602,
- /*   840 */    61,  359,  132,  622,  591,  585,  602,  105,  458,  414,
- /*   850 */    23,  622,  446,  326,   23,  538,  622,  325,  602,  103,
- /*   860 */   427,  530,  309,   56,   57,   47,  583,  582,  584,  584,
+ /*   810 */    51,   51,   50,  238,  313,  411,  597,  414,  411,  276,
+ /*   820 */   214,  600,  411,  366,  213,  381,  601,  134,  274,  500,
+ /*   830 */   414,  167,  130,  414,  621,  411,  354,  414,  376,  601,
+ /*   840 */   135,  129,  601,  100,  590,  584,  601,  104,  522,  521,
+ /*   850 */   414,  621,  224,  273,  600,  167,  327,  282,  600,  601,
+ /*   860 */   103,  468,  521,   56,   57,   47,  582,  581,  583,  583,
  /*   870 */    54,   54,   55,   55,   55,   55,  411,   53,   53,   53,
  /*   880 */    53,   52,   52,   51,   51,   51,   50,  238,  313,  411,
- /*   890 */   264,  414,  411,  276,  359,  219,  157,  214,  357,  366,
- /*   900 */   602,   96,  522,  521,  414,  622,  358,  414,  622,  622,
- /*   910 */   411,  613,  612,  602,  102,  142,  602,   77,  591,  585,
- /*   920 */   529,  540,  231,  426,  308,  414,  622,  622,  468,  521,
- /*   930 */   324,  601,  257,  263,  602,   99,  622,   56,   45,   47,
- /*   940 */   583,  582,  584,  584,   54,   54,   55,   55,   55,   55,
+ /*   890 */    27,  414,  411,  375,  276,  167,  359,  544,   50,  238,
+ /*   900 */   601,   95,  128,  223,  414,  411,  165,  414,  411,  621,
+ /*   910 */   411,  621,  612,  601,  102,  372,  601,   76,  590,  584,
+ /*   920 */   414,  570,  236,  414,  470,  414,  167,  621,  188,  601,
+ /*   930 */    98,  225,  601,  138,  601,  137,  232,   56,   45,   47,
+ /*   940 */   582,  581,  583,  583,   54,   54,   55,   55,   55,   55,
  /*   950 */   411,   53,   53,   53,   53,   52,   52,   51,   51,   51,
- /*   960 */    50,  238,  313,  264,  264,  414,  411,  213,  209,  544,
- /*   970 */   544,  207,  611,   28,  602,  138,   50,  238,  622,  622,
- /*   980 */   381,  414,  503,  140,  323,  222,  274,  622,  590,  589,
- /*   990 */   602,  137,  591,  585,  629,  334,  606,   30,  622,  571,
- /*  1000 */   236,  601,  601,  130,  496,  601,  453,  451,  288,  286,
- /*  1010 */   587,  586,   57,   47,  583,  582,  584,  584,   54,   54,
+ /*   960 */    50,  238,  313,  276,  276,  414,  411,  276,  544,  459,
+ /*   970 */   359,  171,  209,  479,  601,  136,  628,  334,  621,  621,
+ /*   980 */   125,  414,  621,  368,  411,  621,  257,  540,  589,  588,
+ /*   990 */   601,   75,  590,  584,  458,  446,   23,   23,  124,  414,
+ /*  1000 */   326,  325,  621,  427,  324,  309,  600,  288,  601,   92,
+ /*  1010 */   586,  585,   57,   47,  582,  581,  583,  583,   54,   54,
  /*  1020 */    55,   55,   55,   55,  411,   53,   53,   53,   53,   52,
- /*  1030 */    52,   51,   51,   51,   50,  238,  313,  588,  411,  414,
- /*  1040 */   411,  264,  410,  129,  595,  400,   27,  376,  602,  136,
- /*  1050 */   128,  165,  479,  414,  282,  414,  622,  622,  411,  622,
- /*  1060 */   622,  411,  602,   76,  602,   93,  591,  585,  188,  372,
- /*  1070 */   368,  125,  476,  414,  261,  160,  414,  171,  124,  472,
- /*  1080 */   123,   15,  602,   92,  450,  602,   75,   47,  583,  582,
- /*  1090 */   584,  584,   54,   54,   55,   55,   55,   55,  464,   53,
+ /*  1030 */    52,   51,   51,   51,   50,  238,  313,  587,  411,  414,
+ /*  1040 */   411,  207,  611,  476,  171,  472,  160,  123,  601,   91,
+ /*  1050 */   323,  261,   15,  414,  464,  414,  411,  621,  411,  354,
+ /*  1060 */   222,  411,  601,   74,  601,   90,  590,  584,  159,  264,
+ /*  1070 */   158,  414,  461,  414,  621,  600,  414,  121,  120,   25,
+ /*  1080 */   601,   89,  601,  101,  621,  601,   88,   47,  582,  581,
+ /*  1090 */   583,  583,   54,   54,   55,   55,   55,   55,  544,   53,
  /*  1100 */    53,   53,   53,   52,   52,   51,   51,   51,   50,  238,
- /*  1110 */    43,  405,  264,    3,  558,  264,  545,  415,  623,  159,
- /*  1120 */   541,  158,  539,  278,   25,  461,  121,  622,  408,  622,
- /*  1130 */   622,  622,   24,   43,  405,  622,    3,  622,  622,  120,
- /*  1140 */   415,  623,   11,  456,  411,  156,  452,  403,  509,  277,
- /*  1150 */   118,  408,  489,  113,  205,  449,  271,  567,  221,  414,
- /*  1160 */   269,  267,  155,  622,  622,  111,  411,  622,  602,   95,
- /*  1170 */   403,  622,  411,  110,   10,  622,  622,   40,   41,  534,
- /*  1180 */   567,  414,   64,  264,   42,  413,  412,  414,  601,  596,
- /*  1190 */   602,   91,  445,  436,  150,  435,  602,   90,  622,  265,
- /*  1200 */    40,   41,  337,  242,  411,  191,  333,   42,  413,  412,
- /*  1210 */   398,  420,  596,  316,  622,  399,  260,  107,  230,  414,
- /*  1220 */   594,  594,  594,  593,  592,   14,  220,  411,  602,  101,
- /*  1230 */   240,  622,   43,  405,  362,    3,  149,  315,  626,  415,
- /*  1240 */   623,  127,  414,  594,  594,  594,  593,  592,   14,  622,
- /*  1250 */   408,  602,   89,  411,  181,   33,  405,  463,    3,  411,
- /*  1260 */   264,  462,  415,  623,  616,  615,  614,  355,  414,  403,
- /*  1270 */   417,  416,  622,  408,  414,  622,  622,  602,   87,  567,
- /*  1280 */   418,  627,  622,  602,   86,    8,  241,  180,  126,  255,
- /*  1290 */   600,  178,  403,  240,  208,  455,  395,  294,  444,   40,
- /*  1300 */    41,  297,  567,  248,  622,  296,   42,  413,  412,  247,
- /*  1310 */   622,  596,  244,  622,   30,   60,   31,  243,  430,  624,
- /*  1320 */   623,  292,   40,   41,  622,  295,  145,  622,  601,   42,
- /*  1330 */   413,  412,  622,  622,  596,  393,  622,  397,  599,   59,
- /*  1340 */   235,  622,  594,  594,  594,  593,  592,   14,  218,  291,
- /*  1350 */   622,   36,  344,  305,  304,  303,  179,  301,  411,  567,
- /*  1360 */   454,  557,  173,  185,  622,  594,  594,  594,  593,  592,
- /*  1370 */    14,  411,   29,  414,  151,  289,  246,  523,  411,  196,
- /*  1380 */   195,  335,  602,   85,  411,  245,  414,  526,  392,  543,
- /*  1390 */   411,  596,  287,  414,  285,  602,   72,  537,  153,  414,
- /*  1400 */   466,  411,  602,   71,  154,  414,  411,  152,  602,   84,
- /*  1410 */   386,  536,  329,  411,  602,   83,  414,  518,  280,  411,
- /*  1420 */   513,  414,  594,  594,  594,  602,   82,  517,  414,  311,
- /*  1430 */   602,   81,  411,  514,  414,  512,  131,  602,   70,  229,
- /*  1440 */   228,  227,  494,  602,   17,  411,  488,  414,  259,  346,
- /*  1450 */   249,  389,  487,  486,  314,  164,  602,   79,  310,  240,
- /*  1460 */   414,  373,  480,  163,  262,  371,  414,  162,  369,  602,
- /*  1470 */    78,  212,  478,   26,  477,  602,    9,  161,  467,  363,
- /*  1480 */   141,  122,  339,  187,  119,  457,  348,  347,  117,  116,
- /*  1490 */   115,  112,  114,  448,  182,   22,  320,  433,  432,  431,
- /*  1500 */    19,  428,  610,  597,  574,  193,  572,   63,  298,  404,
- /*  1510 */   555,  552,  290,  281,  510,  460,  498,  499,  495,  447,
- /*  1520 */   356,  497,  256,  380,  306,  570,    5,  250,  345,  238,
- /*  1530 */   299,  550,  527,  490,  508,  525,  502,  401,  501,  963,
- /*  1540 */   211,  963,  483,  963,  963,  963,  963,  963,  963,  370,
+ /*  1110 */    43,  405,  263,    3,  610,  264,  140,  415,  622,   24,
+ /*  1120 */   410,   11,  456,  594,  118,  155,  219,  452,  408,  621,
+ /*  1130 */   621,  621,  156,   43,  405,  621,    3,  286,  621,  113,
+ /*  1140 */   415,  622,  111,  445,  411,  400,  557,  403,  545,   10,
+ /*  1150 */   411,  408,  264,  110,  205,  436,  541,  566,  453,  414,
+ /*  1160 */   621,  621,   63,  621,  435,  414,  411,  621,  601,   94,
+ /*  1170 */   403,  621,  411,  337,  601,   86,  150,   40,   41,  534,
+ /*  1180 */   566,  414,  242,  264,   42,  413,  412,  414,  600,  595,
+ /*  1190 */   601,   85,  191,  333,  107,  451,  601,   84,  621,  539,
+ /*  1200 */    40,   41,  420,  230,  411,  149,  316,   42,  413,  412,
+ /*  1210 */   398,  127,  595,  315,  621,  399,  278,  625,  181,  414,
+ /*  1220 */   593,  593,  593,  592,  591,   14,  450,  411,  601,   71,
+ /*  1230 */   240,  621,   43,  405,  264,    3,  615,  180,  264,  415,
+ /*  1240 */   622,  614,  414,  593,  593,  593,  592,  591,   14,  621,
+ /*  1250 */   408,  601,   70,  621,  417,   33,  405,  613,    3,  411,
+ /*  1260 */   264,  411,  415,  622,  418,  626,  178,  509,    8,  403,
+ /*  1270 */   241,  416,  126,  408,  414,  621,  414,  449,  208,  566,
+ /*  1280 */   240,  221,  621,  601,   83,  601,   82,  599,  297,  277,
+ /*  1290 */   296,   30,  403,   31,  395,  264,  295,  397,  489,   40,
+ /*  1300 */    41,  411,  566,  220,  621,  294,   42,  413,  412,  271,
+ /*  1310 */   621,  595,  600,  621,   59,   60,  414,  269,  267,  623,
+ /*  1320 */   622,   36,   40,   41,  621,  601,   81,  598,  235,   42,
+ /*  1330 */   413,  412,  621,  621,  595,  265,  344,  411,  248,  556,
+ /*  1340 */   173,  185,  593,  593,  593,  592,  591,   14,  218,   29,
+ /*  1350 */   621,  543,  414,  305,  304,  303,  179,  301,  411,  566,
+ /*  1360 */   454,  601,   80,  289,  335,  593,  593,  593,  592,  591,
+ /*  1370 */    14,  411,  287,  414,  151,  392,  246,  260,  411,  196,
+ /*  1380 */   195,  523,  601,   69,  411,  245,  414,  526,  537,  285,
+ /*  1390 */   389,  595,  621,  414,  536,  601,   17,  362,  153,  414,
+ /*  1400 */   466,  463,  601,   78,  154,  414,  462,  152,  601,   77,
+ /*  1410 */   355,  255,  621,  455,  601,    9,  621,  386,  444,  517,
+ /*  1420 */   247,  621,  593,  593,  593,  621,  621,  244,  621,  243,
+ /*  1430 */   430,  518,  292,  621,  329,  621,  145,  393,  280,  513,
+ /*  1440 */   291,  131,  621,  514,  621,  621,  311,  621,  259,  346,
+ /*  1450 */   249,  621,  621,  229,  314,  621,  228,  512,  227,  240,
+ /*  1460 */   494,  488,  310,  164,  487,  486,  373,  480,  163,  262,
+ /*  1470 */   369,  371,  162,   26,  212,  478,  477,  161,  141,  363,
+ /*  1480 */   467,  122,  339,  187,  119,  348,  347,  117,  116,  115,
+ /*  1490 */   114,  112,  182,  457,  320,   22,  433,  432,  448,   19,
+ /*  1500 */   609,  431,  428,   62,  193,  596,  573,  298,  555,  552,
+ /*  1510 */   571,  404,  290,  380,  498,  510,  495,  306,  281,  499,
+ /*  1520 */   250,    5,  497,  460,  345,  447,  569,  550,  238,  299,
+ /*  1530 */   527,  525,  508,  961,  502,  501,  961,  401,  961,  211,
+ /*  1540 */   490,  356,  256,  961,  483,  961,  961,  961,  961,  961,
+ /*  1550 */   961,  961,  961,  961,  961,  961,  370,
 };
 static const YYCODETYPE yy_lookahead[] = {
- /*     0 */    19,  222,  223,  224,  225,   24,    1,   26,   77,   78,
- /*    10 */    79,   80,   15,   82,   83,   84,   85,   86,   87,   88,
- /*    20 */    89,   90,   91,   92,  113,   22,   26,   27,  117,   26,
- /*    30 */    49,   50,   81,   82,   83,   84,   85,   86,   87,   88,
- /*    40 */    89,   90,   91,   92,   88,   89,   90,   91,   92,   68,
+ /*     0 */    19,  142,  143,  144,  145,   24,    1,   26,   77,   78,
+ /*    10 */    79,   80,   81,   82,   83,   84,   85,   86,   87,   88,
+ /*    20 */    89,   90,   91,   92,   15,   98,   26,   27,    7,    8,
+ /*    30 */    49,   50,   77,   78,   79,   80,  109,   82,   83,   84,
+ /*    40 */    85,   86,   87,   88,   89,   90,   91,   92,   22,   68,
  /*    50 */    69,   70,   71,   72,   73,   74,   75,   76,   77,   78,
  /*    60 */    79,   80,   23,   82,   83,   84,   85,   86,   87,   88,
- /*    70 */    89,   90,   91,   92,   19,   94,  118,   19,  150,   22,
+ /*    70 */    89,   90,   91,   92,   19,   94,  112,   19,  114,  115,
  /*    80 */    25,   82,   83,   84,   85,   86,   87,   88,   89,   90,
- /*    90 */    91,   92,   19,  165,   94,   95,   96,   94,  118,   99,
- /*   100 */   100,  101,  174,  175,   49,   50,   22,   23,   96,   54,
- /*   110 */   110,   99,  100,  101,    7,    8,   26,   27,   16,  105,
- /*   120 */   106,  107,  110,   68,   69,   70,   71,   72,   73,   74,
- /*   130 */    75,   76,   77,   78,   79,   80,  113,   82,   83,   84,
- /*   140 */    85,   86,   87,   88,   89,   90,   91,   92,   19,   16,
- /*   150 */    92,   67,   98,   24,   96,   97,   98,   99,  100,  101,
- /*   160 */   102,   25,   60,  109,   62,   92,  150,  109,  150,   25,
+ /*    90 */    91,   92,   19,   22,   94,   95,   96,  150,  150,   99,
+ /*   100 */   100,  101,   76,  150,   49,   50,  105,  106,  107,   54,
+ /*   110 */   110,  158,  165,  165,  161,  162,   26,   27,  165,  113,
+ /*   120 */    16,  174,  175,   68,   69,   70,   71,   72,   73,   74,
+ /*   130 */    75,   76,   77,   78,   79,   80,  118,   82,   83,   84,
+ /*   140 */    85,   86,   87,   88,   89,   90,   91,   92,   19,   23,
+ /*   150 */    92,   97,   98,   24,   96,   97,   98,   99,  100,  101,
+ /*   160 */   102,   25,   97,  216,   60,   92,   62,  109,  221,   25,
  /*   170 */    97,   98,   99,  100,  101,  102,   86,   87,   49,   50,
- /*   180 */   116,  165,  109,  165,   94,   95,  118,   97,  170,  171,
- /*   190 */   174,  175,  128,   60,  104,   62,  106,   68,   69,   70,
+ /*   180 */   118,  116,  109,   25,   94,   95,   32,   97,   88,   89,
+ /*   190 */    90,   91,   92,  128,  104,   41,  106,   68,   69,   70,
  /*   200 */    71,   72,   73,   74,   75,   76,   77,   78,   79,   80,
  /*   210 */    11,   82,   83,   84,   85,   86,   87,   88,   89,   90,
- /*   220 */    91,   92,   19,   21,   86,   87,   88,   89,   90,   91,
- /*   230 */    92,  215,   96,  150,   66,   99,  100,  101,   22,  150,
- /*   240 */   138,  118,   26,   27,  161,  162,  110,  103,  165,  231,
- /*   250 */   232,   23,   49,   50,  165,   24,   57,   26,   32,  170,
- /*   260 */   171,  112,   94,  114,  115,   63,   98,   41,  185,  186,
- /*   270 */   118,   68,   69,   70,   71,   72,   73,   74,   75,   76,
- /*   280 */    77,   78,   79,   80,   12,   82,   83,   84,   85,   86,
+ /*   220 */    91,   92,   19,   19,   86,   87,   88,   89,   90,   91,
+ /*   230 */    92,   27,   96,  150,   66,   99,  100,  101,  112,  150,
+ /*   240 */   114,  115,  138,  150,  161,  162,  110,  103,  165,  222,
+ /*   250 */   223,  224,   49,   50,  165,   22,   57,   24,  165,  170,
+ /*   260 */   171,  118,   94,  170,  171,   23,   98,   25,  185,  186,
+ /*   270 */   243,   68,   69,   70,   71,   72,   73,   74,   75,   76,
+ /*   280 */    77,   78,   79,   80,  126,   82,   83,   84,   85,   86,
  /*   290 */    87,   88,   89,   90,   91,   92,   19,  129,  130,  131,
- /*   300 */    28,   23,  100,   25,  105,  106,  107,  150,   26,   27,
- /*   310 */    94,   95,  169,  170,  171,  116,   44,   23,   46,  150,
- /*   320 */   231,  232,  165,   26,   27,   94,   49,   50,   23,   57,
- /*   330 */    25,  174,  175,   22,  165,   26,   27,   26,   27,  136,
- /*   340 */   138,   97,   98,  174,  175,   68,   69,   70,   71,   72,
- /*   350 */    73,   74,   75,   76,   77,   78,   79,   80,   23,   82,
+ /*   300 */    88,   23,  172,  173,  105,  106,  107,  150,   22,   26,
+ /*   310 */    27,  181,   26,   27,   22,  116,   26,   27,   26,  230,
+ /*   320 */   231,  197,  165,  230,  231,  113,   49,   50,  204,  117,
+ /*   330 */    96,  174,  175,   99,  100,  101,   22,   26,   27,  136,
+ /*   340 */    26,   27,  118,   16,  110,   68,   69,   70,   71,   72,
+ /*   350 */    73,   74,   75,   76,   77,   78,   79,   80,  118,   82,
  /*   360 */    83,   84,   85,   86,   87,   88,   89,   90,   91,   92,
- /*   370 */    19,  150,   23,  216,   23,  232,   94,   95,  221,  150,
- /*   380 */    23,  160,   25,  214,  215,  163,  165,   88,  166,  167,
- /*   390 */   168,   94,   95,   23,  165,  174,  175,   88,  160,  150,
- /*   400 */    49,   50,  120,   94,   95,   94,   95,  158,   26,   57,
- /*   410 */   161,  162,  113,  136,  165,  194,  117,  120,   22,   68,
+ /*   370 */    19,  214,  215,  150,   23,   23,  155,   94,   95,   22,
+ /*   380 */    94,   95,  116,  160,   94,   95,   94,   60,  165,   62,
+ /*   390 */   112,   26,  114,  115,  128,   23,   36,  174,  175,   88,
+ /*   400 */    49,   50,   57,  120,   22,   94,   95,   23,   94,   95,
+ /*   410 */   120,   51,   25,  136,  169,  170,  171,  194,   58,   68,
  /*   420 */    69,   70,   71,   72,   73,   74,   75,   76,   77,   78,
- /*   430 */    79,   80,  194,   82,   83,   84,   85,   86,   87,   88,
- /*   440 */    89,   90,   91,   92,   19,  150,   23,  112,   23,  114,
- /*   450 */   115,   25,  142,  143,  144,  145,  218,  105,  106,  107,
- /*   460 */   165,  112,  150,  114,  115,   22,  150,  166,  116,  174,
- /*   470 */   175,   22,   76,  235,   49,   50,   94,  165,  240,  172,
- /*   480 */   173,  165,  112,  155,  114,  115,  174,  175,  181,   11,
- /*   490 */   174,  175,   22,   68,   69,   70,   71,   72,   73,   74,
- /*   500 */    75,   76,   77,   78,   79,   80,  205,   82,   83,   84,
- /*   510 */    85,   86,   87,   88,   89,   90,   91,   92,   19,  160,
- /*   520 */    23,  226,   23,  222,   12,  224,  225,  150,  216,   23,
- /*   530 */    23,   25,   36,   25,   25,  112,  220,  114,  115,  135,
- /*   540 */    28,  137,  165,   26,   27,  119,   30,   51,   49,   50,
- /*   550 */    34,  174,  175,  194,   58,  166,   44,  229,   46,  160,
- /*   560 */    22,   23,  234,   25,   48,  206,  207,   68,   69,   70,
+ /*   430 */    79,   80,   23,   82,   83,   84,   85,   86,   87,   88,
+ /*   440 */    89,   90,   91,   92,   19,  150,   12,   12,   23,  228,
+ /*   450 */   105,  106,  107,   23,  233,   25,  165,   19,  150,   94,
+ /*   460 */   165,  116,   28,   28,  112,  174,  114,  115,  108,  174,
+ /*   470 */   175,   26,   27,  165,   49,   50,  231,   11,   44,   44,
+ /*   480 */    46,   46,  174,  175,  112,  160,  114,  115,   50,   22,
+ /*   490 */    23,   57,   25,   68,   69,   70,   71,   72,   73,   74,
+ /*   500 */    75,   76,   77,   78,   79,   80,  119,   82,   83,   84,
+ /*   510 */    85,   86,   87,   88,   89,   90,   91,   92,   19,  194,
+ /*   520 */   225,   23,   23,  215,   19,   95,  105,  106,  107,  150,
+ /*   530 */    23,  150,   27,   23,   67,   25,  150,  206,  207,   94,
+ /*   540 */    95,  166,  104,  218,  165,   22,  165,  109,   49,   50,
+ /*   550 */   120,  165,   25,  174,  175,  174,  175,   23,   21,  234,
+ /*   560 */   174,  175,   22,   23,  239,   25,   25,   68,   69,   70,
  /*   570 */    71,   72,   73,   74,   75,   76,   77,   78,   79,   80,
- /*   580 */    23,   82,   83,   84,   85,   86,   87,   88,   89,   90,
- /*   590 */    91,   92,   19,  194,  205,  150,   23,  220,   19,  181,
- /*   600 */   182,   95,   97,   95,  108,   67,  188,  169,  170,  171,
- /*   610 */   165,   94,   95,  222,   50,  224,  225,  218,  120,  150,
- /*   620 */   160,  116,   49,   50,   22,   23,  120,   25,  120,   50,
- /*   630 */   161,  162,   19,  128,  165,  244,   22,   23,  193,  240,
- /*   640 */    27,   68,   69,   70,   71,   72,   73,   74,   75,   76,
- /*   650 */    77,   78,   79,   80,  194,   82,   83,   84,   85,   86,
- /*   660 */    87,   88,   89,   90,   91,   92,   19,   25,  104,   67,
- /*   670 */   232,   24,  150,   23,  150,   25,  150,  150,  150,  150,
- /*   680 */   150,   67,   25,  104,    7,    8,    9,  165,  109,  165,
- /*   690 */   245,  165,  165,  165,  165,  165,   49,   50,  174,  175,
- /*   700 */   174,  175,  174,  175,  174,  175,    0,    1,    2,  105,
- /*   710 */   106,  107,  248,  249,  187,   68,   69,   70,   71,   72,
+ /*   580 */   205,   82,   83,   84,   85,   86,   87,   88,   89,   90,
+ /*   590 */    91,   92,   19,   22,   23,  216,   23,  222,  223,  224,
+ /*   600 */    63,  220,   35,  150,  150,  163,  220,   67,  166,  167,
+ /*   610 */   168,  150,  169,  170,  171,  161,  162,   25,  165,  165,
+ /*   620 */   150,  113,   49,   50,   25,  117,  165,  174,  175,   35,
+ /*   630 */     7,    8,    9,  160,  160,  165,  120,  100,   67,  247,
+ /*   640 */   248,   68,   69,   70,   71,   72,   73,   74,   75,   76,
+ /*   650 */    77,   78,   79,   80,  193,   82,   83,   84,   85,   86,
+ /*   660 */    87,   88,   89,   90,   91,   92,   19,  194,  194,  150,
+ /*   670 */   135,   24,  137,   35,  231,  138,  150,  129,  130,  206,
+ /*   680 */   207,   30,   27,  213,  165,   34,  118,   95,    0,    1,
+ /*   690 */     2,  165,  218,  174,  175,   50,   49,   50,   22,   48,
+ /*   700 */   174,  175,   22,   23,   23,  244,  222,  223,  224,  166,
+ /*   710 */   167,  168,  120,  239,   23,   68,   69,   70,   71,   72,
  /*   720 */    73,   74,   75,   76,   77,   78,   79,   80,  150,   82,
  /*   730 */    83,   84,   85,   86,   87,   88,   89,   90,   91,   92,
- /*   740 */    19,  150,  213,  165,  150,  222,  150,  224,  225,  166,
- /*   750 */   167,  168,  174,  175,  129,  130,  165,  150,  165,  165,
- /*   760 */   150,  165,  150,  241,   35,  174,  175,  174,  174,  175,
- /*   770 */    49,   50,  165,   52,   23,  165,   25,  165,  206,  207,
- /*   780 */    23,  197,   25,  187,  174,  175,  174,  175,  204,   68,
+ /*   740 */    19,  150,  173,  165,  181,  182,   24,   67,   26,  104,
+ /*   750 */   181,  188,  174,  175,  150,   39,  165,  150,   52,  150,
+ /*   760 */   150,  150,  150,  144,  145,  174,  175,  249,  250,  165,
+ /*   770 */    49,   50,  165,   52,  165,  165,  165,  165,  174,  175,
+ /*   780 */    29,  174,  175,  174,  175,  174,  175,  160,   22,   68,
  /*   790 */    69,   70,   71,   72,   73,   74,   75,   76,   77,   78,
  /*   800 */    79,   80,  150,   82,   83,   84,   85,   86,   87,   88,
- /*   810 */    89,   90,   91,   92,   19,  150,  150,  165,   35,   23,
- /*   820 */   150,   25,  150,   22,  217,   24,  174,  175,  150,   35,
- /*   830 */   165,  165,  144,  145,  150,  165,  150,  165,  118,  174,
- /*   840 */   175,  150,   22,  165,   49,   50,  174,  175,   23,  165,
- /*   850 */    25,  165,   23,  187,   25,   27,  165,  187,  174,  175,
- /*   860 */    23,   23,   25,   68,   69,   70,   71,   72,   73,   74,
+ /*   810 */    89,   90,   91,   92,   19,  150,   94,  165,  150,  150,
+ /*   820 */   160,  194,  150,  213,  160,   52,  174,  175,   23,   23,
+ /*   830 */   165,   25,   22,  165,  165,  150,  150,  165,   52,  174,
+ /*   840 */   175,   22,  174,  175,   49,   50,  174,  175,  190,  191,
+ /*   850 */   165,  165,  240,   23,  194,   25,  187,  109,  194,  174,
+ /*   860 */   175,  190,  191,   68,   69,   70,   71,   72,   73,   74,
  /*   870 */    75,   76,   77,   78,   79,   80,  150,   82,   83,   84,
  /*   880 */    85,   86,   87,   88,   89,   90,   91,   92,   19,  150,
- /*   890 */   150,  165,  150,  150,  150,  217,   25,  160,   19,  213,
- /*   900 */   174,  175,  190,  191,  165,  165,   27,  165,  165,  165,
- /*   910 */   150,  150,  150,  174,  175,   39,  174,  175,   49,   50,
- /*   920 */    23,  150,   52,  250,  251,  165,  165,  165,  190,  191,
- /*   930 */   187,  194,  241,  193,  174,  175,  165,   68,   69,   70,
+ /*   890 */    22,  165,  150,   23,  150,   25,  150,  166,   91,   92,
+ /*   900 */   174,  175,   22,  217,  165,  150,  102,  165,  150,  165,
+ /*   910 */   150,  165,  150,  174,  175,   19,  174,  175,   49,   50,
+ /*   920 */   165,   86,   87,  165,   23,  165,   25,  165,   24,  174,
+ /*   930 */   175,  187,  174,  175,  174,  175,  205,   68,   69,   70,
  /*   940 */    71,   72,   73,   74,   75,   76,   77,   78,   79,   80,
  /*   950 */   150,   82,   83,   84,   85,   86,   87,   88,   89,   90,
- /*   960 */    91,   92,   19,  150,  150,  165,  150,  160,  160,  166,
- /*   970 */   166,  160,  150,   22,  174,  175,   91,   92,  165,  165,
- /*   980 */    52,  165,   29,  150,  213,  241,   23,  165,   49,   50,
- /*   990 */   174,  175,   49,   50,    1,    2,  173,  126,  165,   86,
- /*  1000 */    87,  194,  194,   22,  181,  194,  193,  193,  205,  205,
+ /*   960 */    91,   92,   19,  150,  150,  165,  150,  150,  166,   23,
+ /*   970 */   150,   25,  160,   20,  174,  175,    1,    2,  165,  165,
+ /*   980 */   104,  165,  165,   43,  150,  165,  240,  150,   49,   50,
+ /*   990 */   174,  175,   49,   50,   23,   23,   25,   25,   53,  165,
+ /*  1000 */   187,  187,  165,   23,  187,   25,  194,  205,  174,  175,
  /*  1010 */    71,   72,   69,   70,   71,   72,   73,   74,   75,   76,
  /*  1020 */    77,   78,   79,   80,  150,   82,   83,   84,   85,   86,
  /*  1030 */    87,   88,   89,   90,   91,   92,   19,   98,  150,  165,
- /*  1040 */   150,  150,  150,   22,  150,  150,   22,   52,  174,  175,
- /*  1050 */    22,  102,   20,  165,  109,  165,  165,  165,  150,  165,
- /*  1060 */   165,  150,  174,  175,  174,  175,   49,   50,   24,   19,
- /*  1070 */    43,  104,   59,  165,  138,  104,  165,   25,   53,   53,
- /*  1080 */    22,    5,  174,  175,  193,  174,  175,   70,   71,   72,
- /*  1090 */    73,   74,   75,   76,   77,   78,   79,   80,    1,   82,
+ /*  1040 */   150,  160,  150,   59,   25,   53,  104,   22,  174,  175,
+ /*  1050 */   213,  138,    5,  165,    1,  165,  150,  165,  150,  150,
+ /*  1060 */   240,  150,  174,  175,  174,  175,   49,   50,  118,  150,
+ /*  1070 */    35,  165,   27,  165,  165,  194,  165,  108,  127,   76,
+ /*  1080 */   174,  175,  174,  175,  165,  174,  175,   70,   71,   72,
+ /*  1090 */    73,   74,   75,   76,   77,   78,   79,   80,  166,   82,
  /*  1100 */    83,   84,   85,   86,   87,   88,   89,   90,   91,   92,
- /*  1110 */    19,   20,  150,   22,  150,  150,  150,   26,   27,  118,
- /*  1120 */   150,   35,  150,  150,   76,   27,  108,  165,   37,  165,
- /*  1130 */   165,  165,   76,   19,   20,  165,   22,  165,  165,  127,
- /*  1140 */    26,   27,   22,    1,  150,   16,   20,   56,  150,  150,
- /*  1150 */   119,   37,  150,  119,  160,  193,  150,   66,  193,  165,
- /*  1160 */   150,  150,  121,  165,  165,  108,  150,  165,  174,  175,
- /*  1170 */    56,  165,  150,  127,   22,  165,  165,   86,   87,   88,
- /*  1180 */    66,  165,   16,  150,   93,   94,   95,  165,  194,   98,
- /*  1190 */   174,  175,  128,   23,   15,   23,  174,  175,  165,  150,
- /*  1200 */    86,   87,   65,  140,  150,   22,    3,   93,   94,   95,
- /*  1210 */   216,    4,   98,  252,  165,  221,  150,  164,  180,  165,
+ /*  1110 */    19,   20,  193,   22,  150,  150,  150,   26,   27,   76,
+ /*  1120 */   150,   22,    1,  150,  119,  121,  217,   20,   37,  165,
+ /*  1130 */   165,  165,   16,   19,   20,  165,   22,  205,  165,  119,
+ /*  1140 */    26,   27,  108,  128,  150,  150,  150,   56,  150,   22,
+ /*  1150 */   150,   37,  150,  127,  160,   23,  150,   66,  193,  165,
+ /*  1160 */   165,  165,   16,  165,   23,  165,  150,  165,  174,  175,
+ /*  1170 */    56,  165,  150,   65,  174,  175,   15,   86,   87,   88,
+ /*  1180 */    66,  165,  140,  150,   93,   94,   95,  165,  194,   98,
+ /*  1190 */   174,  175,   22,    3,  164,  193,  174,  175,  165,  150,
+ /*  1200 */    86,   87,    4,  180,  150,  248,  251,   93,   94,   95,
+ /*  1210 */   216,  180,   98,  251,  165,  221,  150,  149,    6,  165,
  /*  1220 */   129,  130,  131,  132,  133,  134,  193,  150,  174,  175,
- /*  1230 */   116,  165,   19,   20,  150,   22,  249,  252,  149,   26,
- /*  1240 */    27,  180,  165,  129,  130,  131,  132,  133,  134,  165,
- /*  1250 */    37,  174,  175,  150,    6,   19,   20,  150,   22,  150,
- /*  1260 */   150,  150,   26,   27,  149,  149,   13,  150,  165,   56,
- /*  1270 */   149,  159,  165,   37,  165,  165,  165,  174,  175,   66,
- /*  1280 */   146,  147,  165,  174,  175,   25,  152,  151,  154,  150,
- /*  1290 */   194,  151,   56,  116,  160,  150,  123,  202,  150,   86,
- /*  1300 */    87,  199,   66,  193,  165,  200,   93,   94,   95,  150,
- /*  1310 */   165,   98,  150,  165,  126,   22,  124,  150,  150,   26,
- /*  1320 */    27,  150,   86,   87,  165,  201,  150,  165,  194,   93,
- /*  1330 */    94,   95,  165,  165,   98,  150,  165,  122,  203,  125,
- /*  1340 */   227,  165,  129,  130,  131,  132,  133,  134,    5,  150,
- /*  1350 */   165,  135,  218,   10,   11,   12,   13,   14,  150,   66,
- /*  1360 */    17,  157,  118,  157,  165,  129,  130,  131,  132,  133,
- /*  1370 */   134,  150,  104,  165,   31,  210,   33,  176,  150,   86,
- /*  1380 */    87,  247,  174,  175,  150,   42,  165,   94,  121,  211,
- /*  1390 */   150,   98,  210,  165,  210,  174,  175,  211,   55,  165,
+ /*  1230 */   116,  165,   19,   20,  150,   22,  149,  151,  150,   26,
+ /*  1240 */    27,  149,  165,  129,  130,  131,  132,  133,  134,  165,
+ /*  1250 */    37,  174,  175,  165,  149,   19,   20,   13,   22,  150,
+ /*  1260 */   150,  150,   26,   27,  146,  147,  151,  150,   25,   56,
+ /*  1270 */   152,  159,  154,   37,  165,  165,  165,  193,  160,   66,
+ /*  1280 */   116,  193,  165,  174,  175,  174,  175,  194,  199,  150,
+ /*  1290 */   200,  126,   56,  124,  123,  150,  201,  122,  150,   86,
+ /*  1300 */    87,  150,   66,  193,  165,  202,   93,   94,   95,  150,
+ /*  1310 */   165,   98,  194,  165,  125,   22,  165,  150,  150,   26,
+ /*  1320 */    27,  135,   86,   87,  165,  174,  175,  203,  226,   93,
+ /*  1330 */    94,   95,  165,  165,   98,  150,  218,  150,  193,  157,
+ /*  1340 */   118,  157,  129,  130,  131,  132,  133,  134,    5,  104,
+ /*  1350 */   165,  211,  165,   10,   11,   12,   13,   14,  150,   66,
+ /*  1360 */    17,  174,  175,  210,  246,  129,  130,  131,  132,  133,
+ /*  1370 */   134,  150,  210,  165,   31,  121,   33,  150,  150,   86,
+ /*  1380 */    87,  176,  174,  175,  150,   42,  165,   94,  211,  210,
+ /*  1390 */   150,   98,  165,  165,  211,  174,  175,  150,   55,  165,
  /*  1400 */    57,  150,  174,  175,   61,  165,  150,   64,  174,  175,
- /*  1410 */   104,  211,   47,  150,  174,  175,  165,  176,  176,  150,
- /*  1420 */   103,  165,  129,  130,  131,  174,  175,  184,  165,  179,
- /*  1430 */   174,  175,  150,  178,  165,  176,   22,  174,  175,  230,
- /*  1440 */    92,  230,  184,  174,  175,  150,  176,  165,  105,  106,
- /*  1450 */   107,  150,  176,  176,  111,  156,  174,  175,  179,  116,
- /*  1460 */   165,   18,  157,  156,  238,  157,  165,  156,   45,  174,
- /*  1470 */   175,  157,  157,  135,  239,  174,  175,  156,  189,  157,
- /*  1480 */    68,  189,  139,  219,   22,  199,  157,   18,  192,  192,
- /*  1490 */   192,  189,  192,  199,  219,  243,  157,   40,  157,  157,
- /*  1500 */   243,   38,  153,  166,  233,  196,  233,  246,  198,  228,
- /*  1510 */   177,  177,  209,  177,  182,  199,  166,  177,  166,  199,
- /*  1520 */   242,  177,  242,  178,  148,  166,  196,  209,  209,   92,
- /*  1530 */   195,  208,  174,  186,  183,  174,  183,  191,  183,  253,
- /*  1540 */   236,  253,  186,  253,  253,  253,  253,  253,  253,  237,
+ /*  1410 */   150,  150,  165,  150,  174,  175,  165,  104,  150,  184,
+ /*  1420 */   150,  165,  129,  130,  131,  165,  165,  150,  165,  150,
+ /*  1430 */   150,  176,  150,  165,   47,  165,  150,  150,  176,  103,
+ /*  1440 */   150,   22,  165,  178,  165,  165,  179,  165,  105,  106,
+ /*  1450 */   107,  165,  165,  229,  111,  165,   92,  176,  229,  116,
+ /*  1460 */   184,  176,  179,  156,  176,  176,   18,  157,  156,  237,
+ /*  1470 */    45,  157,  156,  135,  157,  157,  238,  156,   68,  157,
+ /*  1480 */   189,  189,  139,  219,   22,  157,   18,  192,  192,  192,
+ /*  1490 */   192,  189,  219,  199,  157,  242,   40,  157,  199,  242,
+ /*  1500 */   153,  157,   38,  245,  196,  166,  232,  198,  177,  177,
+ /*  1510 */   232,  227,  209,  178,  166,  182,  166,  148,  177,  177,
+ /*  1520 */   209,  196,  177,  199,  209,  199,  166,  208,   92,  195,
+ /*  1530 */   174,  174,  183,  252,  183,  183,  252,  191,  252,  235,
+ /*  1540 */   186,  241,  241,  252,  186,  252,  252,  252,  252,  252,
+ /*  1550 */   252,  252,  252,  252,  252,  252,  236,
 };
-#define YY_SHIFT_USE_DFLT (-90)
+#define YY_SHIFT_USE_DFLT (-74)
 #define YY_SHIFT_COUNT (418)
-#define YY_SHIFT_MIN   (-89)
-#define YY_SHIFT_MAX   (1469)
+#define YY_SHIFT_MIN   (-73)
+#define YY_SHIFT_MAX   (1468)
 static const short yy_shift_ofst[] = {
- /*     0 */   993, 1114, 1343, 1114, 1213, 1213,   90,   90,    0,  -19,
- /*    10 */  1213, 1213, 1213, 1213, 1213,  352,  517,  721, 1091, 1213,
+ /*     0 */   975, 1114, 1343, 1114, 1213, 1213,   90,   90,    0,  -19,
+ /*    10 */  1213, 1213, 1213, 1213, 1213,  345,  445,  721, 1091, 1213,
  /*    20 */  1213, 1213, 1213, 1213, 1213, 1213, 1213, 1213, 1213, 1213,
  /*    30 */  1213, 1213, 1213, 1213, 1213, 1213, 1213, 1213, 1213, 1213,
  /*    40 */  1213, 1213, 1213, 1213, 1213, 1213, 1213, 1236, 1213, 1213,
  /*    50 */  1213, 1213, 1213, 1213, 1213, 1213, 1213, 1213, 1213, 1213,
- /*    60 */  1213,  -49,  199,  517,  517,  913,  913,  382, 1177,   55,
- /*    70 */   647,  573,  499,  425,  351,  277,  203,  129,  795,  795,
+ /*    60 */  1213,  199,  445,  445,  835,  835,  365, 1164,   55,  647,
+ /*    70 */   573,  499,  425,  351,  277,  203,  129,  795,  795,  795,
  /*    80 */   795,  795,  795,  795,  795,  795,  795,  795,  795,  795,
- /*    90 */   795,  795,  795,  795,  795,  795,  869,  795,  943, 1017,
- /*   100 */  1017,  -69,  -69,  -69,  -69,   -1,   -1,   58,  138,  -44,
- /*   110 */   517,  517,  517,  517,  517,  517,  517,  517,  517,  517,
- /*   120 */   517,  517,  517,  517,  517,  517,  202,  579,  517,  517,
- /*   130 */   517,  517,  517,  382,  885, 1437,  -90,  -90,  -90, 1293,
- /*   140 */    73,  272,  272,  309,  311,  297,  282,  216,  602,  538,
- /*   150 */   517,  517,  517,  517,  517,  517,  517,  517,  517,  517,
- /*   160 */   517,  517,  517,  517,  517,  517,  517,  517,  517,  517,
- /*   170 */   517,  517,  517,  517,  517,  517,  517,  517,  517,  517,
- /*   180 */   517,  517,  505,  231,  231,  231,  706,   64, 1177, 1177,
- /*   190 */  1177,  -90,  -90,  -90,  136,  168,  168,   12,  496,  496,
- /*   200 */   496,  506,  423,  512,  370,  349,  335,  149,  149,  149,
- /*   210 */   149,  604,  516,  149,  149,  508,    3,  299,  677,  871,
- /*   220 */   613,  613,  879,  871,  879,  144,  382,  226,  382,  226,
- /*   230 */   564,  226,  613,  226,  226,  404,  625,  625,  382,  426,
- /*   240 */   -89,  801, 1463, 1244, 1244, 1457, 1457, 1244, 1462, 1412,
- /*   250 */  1188, 1469, 1469, 1469, 1469, 1244, 1188, 1462, 1412, 1412,
- /*   260 */  1244, 1443, 1338, 1423, 1244, 1244, 1443, 1244, 1443, 1244,
- /*   270 */  1443, 1414, 1306, 1306, 1306, 1365, 1348, 1348, 1414, 1306,
- /*   280 */  1317, 1306, 1365, 1306, 1306, 1267, 1268, 1267, 1268, 1267,
- /*   290 */  1268, 1244, 1244, 1216, 1214, 1215, 1192, 1173, 1188, 1177,
- /*   300 */  1260, 1253, 1253, 1248, 1248, 1248, 1248,  -90,  -90,  -90,
- /*   310 */   -90,  -90,  -90,  939,  102,  614,   84,  133,   14,  837,
- /*   320 */   396,  829,  825,  796,  757,  751,  650,  357,  244,  107,
- /*   330 */    54,  305,  278, 1207, 1203, 1183, 1063, 1179, 1137, 1166,
- /*   340 */  1172, 1170, 1064, 1152, 1046, 1057, 1034, 1126, 1041, 1129,
- /*   350 */  1142, 1031, 1120, 1012, 1056, 1048, 1018, 1098, 1086, 1001,
- /*   360 */  1097, 1076, 1058,  971,  936, 1026, 1052, 1025, 1013, 1027,
- /*   370 */   967, 1044, 1032, 1050,  945,  949, 1028,  995, 1024, 1021,
- /*   380 */   963,  981,  928,  953,  951,  870,  876,  897,  838,  720,
- /*   390 */   828,  794,  820,  498,  642,  783,  657,  729,  642,  557,
- /*   400 */   507,  509,  497,  470,  478,  449,  294,  228,  443,   23,
- /*   410 */   152,  123,   68,  -20,  -42,   57,   39,   -3,    5,
+ /*    90 */   795,  795,  795,  795,  795,  869,  795,  943, 1017, 1017,
+ /*   100 */   -69,  -45,  -45,  -45,  -45,  -45,   -1,   58,  138,  100,
+ /*   110 */   445,  445,  445,  445,  445,  445,  445,  445,  445,  445,
+ /*   120 */   445,  445,  445,  445,  445,  445,  537,  438,  445,  445,
+ /*   130 */   445,  445,  445,  365,  807, 1436,  -74,  -74,  -74, 1293,
+ /*   140 */    73,  434,  434,  311,  314,  290,  283,  286,  540,  467,
+ /*   150 */   445,  445,  445,  445,  445,  445,  445,  445,  445,  445,
+ /*   160 */   445,  445,  445,  445,  445,  445,  445,  445,  445,  445,
+ /*   170 */   445,  445,  445,  445,  445,  445,  445,  445,  445,  445,
+ /*   180 */   445,  445,   65,  722,  722,  722,  688,  266, 1164, 1164,
+ /*   190 */  1164,  -74,  -74,  -74,  136,  168,  168,  234,  360,  360,
+ /*   200 */   360,  430,  372,  435,  352,  278,  126,  -36,  -36,  -36,
+ /*   210 */   -36,  421,  651,  -36,  -36,  592,  292,  212,  623,  158,
+ /*   220 */   204,  204,  505,  158,  505,  144,  365,  154,  365,  154,
+ /*   230 */   645,  154,  204,  154,  154,  535,  548,  548,  365,  387,
+ /*   240 */   508,  233, 1464, 1222, 1222, 1456, 1456, 1222, 1462, 1410,
+ /*   250 */  1165, 1468, 1468, 1468, 1468, 1222, 1165, 1462, 1410, 1410,
+ /*   260 */  1222, 1448, 1338, 1425, 1222, 1222, 1448, 1222, 1448, 1222,
+ /*   270 */  1448, 1419, 1313, 1313, 1313, 1387, 1364, 1364, 1419, 1313,
+ /*   280 */  1336, 1313, 1387, 1313, 1313, 1254, 1245, 1254, 1245, 1254,
+ /*   290 */  1245, 1222, 1222, 1186, 1189, 1175, 1169, 1171, 1165, 1164,
+ /*   300 */  1243, 1244, 1244, 1212, 1212, 1212, 1212,  -74,  -74,  -74,
+ /*   310 */   -74,  -74,  -74,  939,  104,  680,  571,  327,    1,  980,
+ /*   320 */    26,  972,  971,  946,  901,  870,  830,  806,   54,   21,
+ /*   330 */   -73,  510,  242, 1198, 1190, 1170, 1042, 1161, 1108, 1146,
+ /*   340 */  1141, 1132, 1015, 1127, 1026, 1034, 1020, 1107, 1004, 1116,
+ /*   350 */  1121, 1005, 1099,  951, 1043, 1003,  969, 1045, 1035,  950,
+ /*   360 */  1053, 1047, 1025,  942,  913,  992, 1019,  945,  984,  940,
+ /*   370 */   876,  904,  953,  896,  748,  804,  880,  786,  868,  819,
+ /*   380 */   805,  810,  773,  751,  766,  706,  716,  691,  681,  568,
+ /*   390 */   655,  638,  676,  516,  541,  594,  599,  567,  541,  534,
+ /*   400 */   507,  527,  498,  523,  466,  382,  409,  384,  357,    6,
+ /*   410 */   240,  224,  143,   62,   18,   71,   39,    9,    5,
 };
-#define YY_REDUCE_USE_DFLT (-222)
+#define YY_REDUCE_USE_DFLT (-142)
 #define YY_REDUCE_COUNT (312)
-#define YY_REDUCE_MIN   (-221)
-#define YY_REDUCE_MAX   (1376)
+#define YY_REDUCE_MIN   (-141)
+#define YY_REDUCE_MAX   (1369)
 static const short yy_reduce_ofst[] = {
- /*     0 */   310,  994, 1134,  221,  169,  157,   89,   18,   83,  301,
- /*    10 */   377,  316,  312,   16,  295,  238,  249,  391, 1301, 1295,
- /*    20 */  1282, 1269, 1263, 1256, 1251, 1240, 1234, 1228, 1221, 1208,
- /*    30 */  1109, 1103, 1077, 1054, 1022, 1016,  911,  908,  890,  888,
- /*    40 */   874,  816,  800,  760,  742,  739,  726,  684,  672,  665,
- /*    50 */   652,  612,  610,  594,  591,  578,  530,  528,  526,  524,
- /*    60 */   -72, -221,  399,  469,  445,  438,  143,  222,  359,  523,
- /*    70 */   523,  523,  523,  523,  523,  523,  523,  523,  523,  523,
- /*    80 */   523,  523,  523,  523,  523,  523,  523,  523,  523,  523,
- /*    90 */   523,  523,  523,  523,  523,  523,  523,  523,  523,  523,
- /*   100 */   523,  523,  523,  523,  523,  523,  523,  307,  523,  523,
- /*   110 */  1110,  678, 1033,  965,  962,  891,  814,  813,  744,  771,
- /*   120 */   691,  607,  522,  743,  686,  740,  328,  418,  670,  666,
- /*   130 */   596,  527,  529,  583,  523,  523,  523,  523,  523,  593,
- /*   140 */   823,  738,  712,  892, 1199, 1185, 1176, 1171,  673,  673,
- /*   150 */  1168, 1167, 1162, 1159, 1148, 1145, 1139, 1117, 1111, 1107,
- /*   160 */  1084, 1066, 1049, 1011, 1010, 1006, 1002,  999,  998,  973,
- /*   170 */   972,  970,  966,  964,  895,  894,  892,  833,  822,  762,
- /*   180 */   761,  229,  811,  804,  803,  389,  688,  808,  807,  737,
- /*   190 */   460,  464,  572,  584, 1356, 1361, 1358, 1347, 1355, 1353,
- /*   200 */  1351, 1323, 1335, 1346, 1335, 1335, 1335, 1335, 1335, 1335,
- /*   210 */  1335, 1312, 1304, 1335, 1335, 1323, 1359, 1330, 1376, 1320,
- /*   220 */  1319, 1318, 1280, 1316, 1278, 1345, 1352, 1344, 1350, 1340,
- /*   230 */  1332, 1336, 1303, 1334, 1333, 1281, 1273, 1271, 1337, 1310,
- /*   240 */  1309, 1349, 1261, 1342, 1341, 1257, 1252, 1339, 1275, 1302,
- /*   250 */  1294, 1300, 1298, 1297, 1296, 1329, 1286, 1264, 1292, 1289,
- /*   260 */  1322, 1321, 1235, 1226, 1315, 1314, 1311, 1308, 1307, 1305,
- /*   270 */  1299, 1279, 1277, 1276, 1270, 1258, 1211, 1209, 1250, 1259,
- /*   280 */  1255, 1242, 1243, 1241, 1201, 1200, 1184, 1186, 1182, 1178,
- /*   290 */  1165, 1206, 1204, 1113, 1135, 1095, 1124, 1105, 1102, 1096,
- /*   300 */  1112, 1140, 1136, 1121, 1116, 1115, 1089,  985,  961,  987,
- /*   310 */  1061, 1038, 1053,
+ /*     0 */  -141,  994, 1118,  223,  157,  -53,   93,   89,   83,  375,
+ /*    10 */   386,  381,  379,  308,  295,  325,  -47,   27, 1240, 1234,
+ /*    20 */  1228, 1221, 1208, 1187, 1151, 1111, 1109, 1077, 1054, 1022,
+ /*    30 */  1016, 1000,  911,  908,  906,  890,  888,  874,  834,  816,
+ /*    40 */   800,  760,  758,  755,  742,  739,  726,  685,  672,  668,
+ /*    50 */   665,  652,  611,  609,  607,  604,  591,  578,  526,  519,
+ /*    60 */   453,  474,  454,  461,  443,  245,  442,  473,  484,  484,
+ /*    70 */   484,  484,  484,  484,  484,  484,  484,  484,  484,  484,
+ /*    80 */   484,  484,  484,  484,  484,  484,  484,  484,  484,  484,
+ /*    90 */   484,  484,  484,  484,  484,  484,  484,  484,  484,  484,
+ /*   100 */   484,  484,  484,  484,  484,  484,  484,  130,  484,  484,
+ /*   110 */  1145,  909, 1110, 1088, 1084, 1033, 1002,  965,  820,  837,
+ /*   120 */   746,  686,  612,  817,  610,  919,  221,  563,  814,  813,
+ /*   130 */   744,  669,  470,  543,  484,  484,  484,  484,  484,  291,
+ /*   140 */   569,  671,  658,  970, 1290, 1287, 1286, 1282,  518,  518,
+ /*   150 */  1280, 1279, 1277, 1270, 1268, 1263, 1261, 1260, 1256, 1251,
+ /*   160 */  1247, 1227, 1185, 1168, 1167, 1159, 1148, 1139, 1117, 1066,
+ /*   170 */  1049, 1006,  998,  996,  995,  973,  970,  966,  964,  892,
+ /*   180 */   762,  -52,  881,  932,  802,  731,  619,  812,  664,  660,
+ /*   190 */   627,  392,  331,  124, 1358, 1357, 1356, 1354, 1352, 1351,
+ /*   200 */  1349, 1319, 1334, 1346, 1334, 1334, 1334, 1334, 1334, 1334,
+ /*   210 */  1334, 1320, 1304, 1334, 1334, 1319, 1360, 1325, 1369, 1326,
+ /*   220 */  1315, 1311, 1301, 1324, 1300, 1335, 1350, 1345, 1348, 1342,
+ /*   230 */  1333, 1341, 1303, 1332, 1331, 1284, 1278, 1274, 1339, 1309,
+ /*   240 */  1308, 1347, 1258, 1344, 1340, 1257, 1253, 1337, 1273, 1302,
+ /*   250 */  1299, 1298, 1297, 1296, 1295, 1328, 1294, 1264, 1292, 1291,
+ /*   260 */  1322, 1321, 1238, 1232, 1318, 1317, 1316, 1314, 1312, 1310,
+ /*   270 */  1307, 1283, 1289, 1288, 1285, 1276, 1229, 1224, 1267, 1281,
+ /*   280 */  1265, 1262, 1235, 1255, 1205, 1183, 1179, 1177, 1162, 1140,
+ /*   290 */  1153, 1184, 1182, 1102, 1124, 1103, 1095, 1090, 1089, 1093,
+ /*   300 */  1112, 1115, 1086, 1105, 1092, 1087, 1068,  962,  955,  957,
+ /*   310 */  1031, 1023, 1030,
 };
 static const YYACTIONTYPE yy_default[] = {
- /*     0 */   636,  872,  961,  961,  961,  872,  901,  901,  961,  760,
- /*    10 */   961,  961,  961,  961,  870,  961,  961,  935,  961,  961,
- /*    20 */   961,  961,  961,  961,  961,  961,  961,  961,  961,  961,
- /*    30 */   961,  961,  961,  961,  961,  961,  961,  961,  961,  961,
- /*    40 */   961,  961,  961,  961,  961,  961,  961,  961,  961,  961,
- /*    50 */   961,  961,  961,  961,  961,  961,  961,  961,  961,  961,
- /*    60 */   961,  844,  961,  961,  961,  901,  901,  675,  764,  795,
- /*    70 */   961,  961,  961,  961,  961,  961,  961,  961,  934,  936,
- /*    80 */   810,  809,  803,  802,  914,  775,  800,  793,  786,  797,
- /*    90 */   873,  866,  867,  865,  869,  874,  961,  796,  832,  850,
- /*   100 */   831,  849,  856,  848,  834,  843,  833,  667,  835,  836,
- /*   110 */   961,  961,  961,  961,  961,  961,  961,  961,  961,  961,
- /*   120 */   961,  961,  961,  961,  961,  961,  662,  729,  961,  961,
- /*   130 */   961,  961,  961,  961,  837,  838,  853,  852,  851,  961,
- /*   140 */   961,  961,  961,  961,  961,  961,  961,  961,  961,  961,
- /*   150 */   961,  941,  939,  961,  885,  961,  961,  961,  961,  961,
- /*   160 */   961,  961,  961,  961,  961,  961,  961,  961,  961,  961,
- /*   170 */   961,  961,  961,  961,  961,  961,  961,  961,  961,  961,
- /*   180 */   961,  642,  961,  760,  760,  760,  636,  961,  961,  961,
- /*   190 */   961,  953,  764,  754,  720,  961,  961,  961,  961,  961,
- /*   200 */   961,  961,  961,  961,  961,  961,  961,  805,  743,  924,
- /*   210 */   926,  961,  907,  741,  664,  762,  677,  752,  644,  799,
- /*   220 */   777,  777,  919,  799,  919,  701,  961,  789,  961,  789,
- /*   230 */   698,  789,  777,  789,  789,  868,  961,  961,  961,  761,
- /*   240 */   752,  961,  946,  768,  768,  938,  938,  768,  811,  733,
- /*   250 */   799,  740,  740,  740,  740,  768,  799,  811,  733,  733,
- /*   260 */   768,  659,  913,  911,  768,  768,  659,  768,  659,  768,
- /*   270 */   659,  878,  731,  731,  731,  716,  882,  882,  878,  731,
- /*   280 */   701,  731,  716,  731,  731,  781,  776,  781,  776,  781,
- /*   290 */   776,  768,  768,  961,  794,  782,  792,  790,  799,  961,
- /*   300 */   719,  652,  652,  641,  641,  641,  641,  958,  958,  953,
- /*   310 */   703,  703,  685,  961,  961,  961,  961,  961,  961,  961,
- /*   320 */   887,  961,  961,  961,  961,  961,  961,  961,  961,  961,
- /*   330 */   961,  961,  961,  961,  637,  948,  961,  961,  945,  961,
- /*   340 */   961,  961,  961,  961,  961,  961,  961,  961,  961,  961,
- /*   350 */   961,  961,  961,  961,  961,  961,  961,  961,  961,  917,
- /*   360 */   961,  961,  961,  961,  961,  961,  910,  909,  961,  961,
- /*   370 */   961,  961,  961,  961,  961,  961,  961,  961,  961,  961,
- /*   380 */   961,  961,  961,  961,  961,  961,  961,  961,  961,  961,
- /*   390 */   961,  961,  961,  961,  791,  961,  783,  961,  871,  961,
- /*   400 */   961,  961,  961,  961,  961,  961,  961,  961,  961,  746,
- /*   410 */   820,  961,  819,  823,  818,  669,  961,  650,  961,  633,
- /*   420 */   638,  957,  960,  959,  956,  955,  954,  949,  947,  944,
- /*   430 */   943,  942,  940,  937,  933,  891,  889,  896,  895,  894,
- /*   440 */   893,  892,  890,  888,  886,  806,  804,  801,  798,  932,
- /*   450 */   884,  742,  739,  738,  658,  950,  916,  925,  923,  812,
- /*   460 */   922,  921,  920,  918,  915,  902,  808,  807,  734,  876,
- /*   470 */   875,  661,  906,  905,  904,  908,  912,  903,  770,  660,
- /*   480 */   657,  666,  723,  722,  730,  728,  727,  726,  725,  724,
- /*   490 */   721,  668,  676,  687,  715,  700,  699,  881,  883,  880,
- /*   500 */   879,  708,  707,  713,  712,  711,  710,  709,  706,  705,
- /*   510 */   704,  697,  696,  702,  695,  718,  717,  714,  694,  737,
- /*   520 */   736,  735,  732,  693,  692,  691,  823,  690,  689,  829,
- /*   530 */   828,  816,  860,  757,  756,  755,  767,  766,  779,  778,
- /*   540 */   814,  813,  780,  765,  759,  758,  774,  773,  772,  771,
- /*   550 */   763,  753,  785,  788,  787,  784,  845,  862,  769,  859,
- /*   560 */   931,  930,  929,  928,  927,  864,  863,  830,  827,  680,
- /*   570 */   681,  900,  898,  899,  897,  683,  682,  679,  678,  861,
- /*   580 */   748,  747,  857,  854,  846,  841,  858,  855,  847,  842,
- /*   590 */   840,  839,  825,  824,  822,  821,  817,  826,  671,  749,
- /*   600 */   745,  744,  815,  751,  750,  688,  686,  684,  665,  663,
- /*   610 */   656,  654,  653,  655,  651,  649,  648,  647,  646,  645,
- /*   620 */   674,  673,  672,  670,  669,  643,  640,  639,  635,  634,
- /*   630 */   632,
+ /*     0 */   635,  870,  959,  959,  959,  870,  899,  899,  959,  759,
+ /*    10 */   959,  959,  959,  959,  868,  959,  959,  933,  959,  959,
+ /*    20 */   959,  959,  959,  959,  959,  959,  959,  959,  959,  959,
+ /*    30 */   959,  959,  959,  959,  959,  959,  959,  959,  959,  959,
+ /*    40 */   959,  959,  959,  959,  959,  959,  959,  959,  959,  959,
+ /*    50 */   959,  959,  959,  959,  959,  959,  959,  959,  959,  959,
+ /*    60 */   959,  959,  959,  959,  899,  899,  674,  763,  794,  959,
+ /*    70 */   959,  959,  959,  959,  959,  959,  959,  932,  934,  809,
+ /*    80 */   808,  802,  801,  912,  774,  799,  792,  785,  796,  871,
+ /*    90 */   864,  865,  863,  867,  872,  959,  795,  831,  848,  830,
+ /*   100 */   842,  847,  854,  846,  843,  833,  832,  666,  834,  835,
+ /*   110 */   959,  959,  959,  959,  959,  959,  959,  959,  959,  959,
+ /*   120 */   959,  959,  959,  959,  959,  959,  661,  728,  959,  959,
+ /*   130 */   959,  959,  959,  959,  836,  837,  851,  850,  849,  959,
+ /*   140 */   959,  959,  959,  959,  959,  959,  959,  959,  959,  959,
+ /*   150 */   959,  939,  937,  959,  883,  959,  959,  959,  959,  959,
+ /*   160 */   959,  959,  959,  959,  959,  959,  959,  959,  959,  959,
+ /*   170 */   959,  959,  959,  959,  959,  959,  959,  959,  959,  959,
+ /*   180 */   959,  641,  959,  759,  759,  759,  635,  959,  959,  959,
+ /*   190 */   959,  951,  763,  753,  719,  959,  959,  959,  959,  959,
+ /*   200 */   959,  959,  959,  959,  959,  959,  959,  804,  742,  922,
+ /*   210 */   924,  959,  905,  740,  663,  761,  676,  751,  643,  798,
+ /*   220 */   776,  776,  917,  798,  917,  700,  959,  788,  959,  788,
+ /*   230 */   697,  788,  776,  788,  788,  866,  959,  959,  959,  760,
+ /*   240 */   751,  959,  944,  767,  767,  936,  936,  767,  810,  732,
+ /*   250 */   798,  739,  739,  739,  739,  767,  798,  810,  732,  732,
+ /*   260 */   767,  658,  911,  909,  767,  767,  658,  767,  658,  767,
+ /*   270 */   658,  876,  730,  730,  730,  715,  880,  880,  876,  730,
+ /*   280 */   700,  730,  715,  730,  730,  780,  775,  780,  775,  780,
+ /*   290 */   775,  767,  767,  959,  793,  781,  791,  789,  798,  959,
+ /*   300 */   718,  651,  651,  640,  640,  640,  640,  956,  956,  951,
+ /*   310 */   702,  702,  684,  959,  959,  959,  959,  959,  959,  959,
+ /*   320 */   885,  959,  959,  959,  959,  959,  959,  959,  959,  959,
+ /*   330 */   959,  959,  959,  959,  636,  946,  959,  959,  943,  959,
+ /*   340 */   959,  959,  959,  959,  959,  959,  959,  959,  959,  959,
+ /*   350 */   959,  959,  959,  959,  959,  959,  959,  959,  959,  915,
+ /*   360 */   959,  959,  959,  959,  959,  959,  908,  907,  959,  959,
+ /*   370 */   959,  959,  959,  959,  959,  959,  959,  959,  959,  959,
+ /*   380 */   959,  959,  959,  959,  959,  959,  959,  959,  959,  959,
+ /*   390 */   959,  959,  959,  959,  790,  959,  782,  959,  869,  959,
+ /*   400 */   959,  959,  959,  959,  959,  959,  959,  959,  959,  745,
+ /*   410 */   819,  959,  818,  822,  817,  668,  959,  649,  959,  632,
+ /*   420 */   637,  955,  958,  957,  954,  953,  952,  947,  945,  942,
+ /*   430 */   941,  940,  938,  935,  931,  889,  887,  894,  893,  892,
+ /*   440 */   891,  890,  888,  886,  884,  805,  803,  800,  797,  930,
+ /*   450 */   882,  741,  738,  737,  657,  948,  914,  923,  921,  811,
+ /*   460 */   920,  919,  918,  916,  913,  900,  807,  806,  733,  874,
+ /*   470 */   873,  660,  904,  903,  902,  906,  910,  901,  769,  659,
+ /*   480 */   656,  665,  722,  721,  729,  727,  726,  725,  724,  723,
+ /*   490 */   720,  667,  675,  686,  714,  699,  698,  879,  881,  878,
+ /*   500 */   877,  707,  706,  712,  711,  710,  709,  708,  705,  704,
+ /*   510 */   703,  696,  695,  701,  694,  717,  716,  713,  693,  736,
+ /*   520 */   735,  734,  731,  692,  691,  690,  822,  689,  688,  828,
+ /*   530 */   827,  815,  858,  756,  755,  754,  766,  765,  778,  777,
+ /*   540 */   813,  812,  779,  764,  758,  757,  773,  772,  771,  770,
+ /*   550 */   762,  752,  784,  787,  786,  783,  860,  768,  857,  929,
+ /*   560 */   928,  927,  926,  925,  862,  861,  829,  826,  679,  680,
+ /*   570 */   898,  896,  897,  895,  682,  681,  678,  677,  859,  747,
+ /*   580 */   746,  855,  852,  844,  840,  856,  853,  845,  841,  839,
+ /*   590 */   838,  824,  823,  821,  820,  816,  825,  670,  748,  744,
+ /*   600 */   743,  814,  750,  749,  687,  685,  683,  664,  662,  655,
+ /*   610 */   653,  652,  654,  650,  648,  647,  646,  645,  644,  673,
+ /*   620 */   672,  671,  669,  668,  642,  639,  638,  634,  633,  631,
 };
 
 /* The next table maps tokens into fallback tokens.  If a construct
@@ -98471,15 +100294,14 @@
   "joinop",        "indexed_opt",   "on_opt",        "using_opt",   
   "joinop2",       "inscollist",    "sortlist",      "sortitem",    
   "nexprlist",     "setlist",       "insert_cmd",    "inscollist_opt",
-  "itemlist",      "exprlist",      "likeop",        "escape",      
-  "between_op",    "in_op",         "case_operand",  "case_exprlist",
-  "case_else",     "uniqueflag",    "collate",       "nmnum",       
-  "plus_opt",      "number",        "trigger_decl",  "trigger_cmd_list",
-  "trigger_time",  "trigger_event",  "foreach_clause",  "when_clause", 
-  "trigger_cmd",   "trnm",          "tridxby",       "database_kw_opt",
-  "key_opt",       "add_column_fullname",  "kwcolumn_opt",  "create_vtab", 
-  "vtabarglist",   "vtabarg",       "vtabargtoken",  "lp",          
-  "anylist",     
+  "itemlist",      "exprlist",      "likeop",        "between_op",  
+  "in_op",         "case_operand",  "case_exprlist",  "case_else",   
+  "uniqueflag",    "collate",       "nmnum",         "plus_opt",    
+  "number",        "trigger_decl",  "trigger_cmd_list",  "trigger_time",
+  "trigger_event",  "foreach_clause",  "when_clause",   "trigger_cmd", 
+  "trnm",          "tridxby",       "database_kw_opt",  "key_opt",     
+  "add_column_fullname",  "kwcolumn_opt",  "create_vtab",   "vtabarglist", 
+  "vtabarg",       "vtabargtoken",  "lp",            "anylist",     
 };
 #endif /* NDEBUG */
 
@@ -98699,124 +100521,123 @@
  /* 209 */ "likeop ::= NOT LIKE_KW",
  /* 210 */ "likeop ::= MATCH",
  /* 211 */ "likeop ::= NOT MATCH",
- /* 212 */ "escape ::= ESCAPE expr",
- /* 213 */ "escape ::=",
- /* 214 */ "expr ::= expr likeop expr escape",
- /* 215 */ "expr ::= expr ISNULL|NOTNULL",
- /* 216 */ "expr ::= expr NOT NULL",
- /* 217 */ "expr ::= expr IS expr",
- /* 218 */ "expr ::= expr IS NOT expr",
- /* 219 */ "expr ::= NOT expr",
- /* 220 */ "expr ::= BITNOT expr",
- /* 221 */ "expr ::= MINUS expr",
- /* 222 */ "expr ::= PLUS expr",
- /* 223 */ "between_op ::= BETWEEN",
- /* 224 */ "between_op ::= NOT BETWEEN",
- /* 225 */ "expr ::= expr between_op expr AND expr",
- /* 226 */ "in_op ::= IN",
- /* 227 */ "in_op ::= NOT IN",
- /* 228 */ "expr ::= expr in_op LP exprlist RP",
- /* 229 */ "expr ::= LP select RP",
- /* 230 */ "expr ::= expr in_op LP select RP",
- /* 231 */ "expr ::= expr in_op nm dbnm",
- /* 232 */ "expr ::= EXISTS LP select RP",
- /* 233 */ "expr ::= CASE case_operand case_exprlist case_else END",
- /* 234 */ "case_exprlist ::= case_exprlist WHEN expr THEN expr",
- /* 235 */ "case_exprlist ::= WHEN expr THEN expr",
- /* 236 */ "case_else ::= ELSE expr",
- /* 237 */ "case_else ::=",
- /* 238 */ "case_operand ::= expr",
- /* 239 */ "case_operand ::=",
- /* 240 */ "exprlist ::= nexprlist",
- /* 241 */ "exprlist ::=",
- /* 242 */ "nexprlist ::= nexprlist COMMA expr",
- /* 243 */ "nexprlist ::= expr",
- /* 244 */ "cmd ::= createkw uniqueflag INDEX ifnotexists nm dbnm ON nm LP idxlist RP",
- /* 245 */ "uniqueflag ::= UNIQUE",
- /* 246 */ "uniqueflag ::=",
- /* 247 */ "idxlist_opt ::=",
- /* 248 */ "idxlist_opt ::= LP idxlist RP",
- /* 249 */ "idxlist ::= idxlist COMMA nm collate sortorder",
- /* 250 */ "idxlist ::= nm collate sortorder",
- /* 251 */ "collate ::=",
- /* 252 */ "collate ::= COLLATE ids",
- /* 253 */ "cmd ::= DROP INDEX ifexists fullname",
- /* 254 */ "cmd ::= VACUUM",
- /* 255 */ "cmd ::= VACUUM nm",
- /* 256 */ "cmd ::= PRAGMA nm dbnm",
- /* 257 */ "cmd ::= PRAGMA nm dbnm EQ nmnum",
- /* 258 */ "cmd ::= PRAGMA nm dbnm LP nmnum RP",
- /* 259 */ "cmd ::= PRAGMA nm dbnm EQ minus_num",
- /* 260 */ "cmd ::= PRAGMA nm dbnm LP minus_num RP",
- /* 261 */ "nmnum ::= plus_num",
- /* 262 */ "nmnum ::= nm",
- /* 263 */ "nmnum ::= ON",
- /* 264 */ "nmnum ::= DELETE",
- /* 265 */ "nmnum ::= DEFAULT",
- /* 266 */ "plus_num ::= plus_opt number",
- /* 267 */ "minus_num ::= MINUS number",
- /* 268 */ "number ::= INTEGER|FLOAT",
- /* 269 */ "plus_opt ::= PLUS",
- /* 270 */ "plus_opt ::=",
- /* 271 */ "cmd ::= createkw trigger_decl BEGIN trigger_cmd_list END",
- /* 272 */ "trigger_decl ::= temp TRIGGER ifnotexists nm dbnm trigger_time trigger_event ON fullname foreach_clause when_clause",
- /* 273 */ "trigger_time ::= BEFORE",
- /* 274 */ "trigger_time ::= AFTER",
- /* 275 */ "trigger_time ::= INSTEAD OF",
- /* 276 */ "trigger_time ::=",
- /* 277 */ "trigger_event ::= DELETE|INSERT",
- /* 278 */ "trigger_event ::= UPDATE",
- /* 279 */ "trigger_event ::= UPDATE OF inscollist",
- /* 280 */ "foreach_clause ::=",
- /* 281 */ "foreach_clause ::= FOR EACH ROW",
- /* 282 */ "when_clause ::=",
- /* 283 */ "when_clause ::= WHEN expr",
- /* 284 */ "trigger_cmd_list ::= trigger_cmd_list trigger_cmd SEMI",
- /* 285 */ "trigger_cmd_list ::= trigger_cmd SEMI",
- /* 286 */ "trnm ::= nm",
- /* 287 */ "trnm ::= nm DOT nm",
- /* 288 */ "tridxby ::=",
- /* 289 */ "tridxby ::= INDEXED BY nm",
- /* 290 */ "tridxby ::= NOT INDEXED",
- /* 291 */ "trigger_cmd ::= UPDATE orconf trnm tridxby SET setlist where_opt",
- /* 292 */ "trigger_cmd ::= insert_cmd INTO trnm inscollist_opt VALUES LP itemlist RP",
- /* 293 */ "trigger_cmd ::= insert_cmd INTO trnm inscollist_opt select",
- /* 294 */ "trigger_cmd ::= DELETE FROM trnm tridxby where_opt",
- /* 295 */ "trigger_cmd ::= select",
- /* 296 */ "expr ::= RAISE LP IGNORE RP",
- /* 297 */ "expr ::= RAISE LP raisetype COMMA nm RP",
- /* 298 */ "raisetype ::= ROLLBACK",
- /* 299 */ "raisetype ::= ABORT",
- /* 300 */ "raisetype ::= FAIL",
- /* 301 */ "cmd ::= DROP TRIGGER ifexists fullname",
- /* 302 */ "cmd ::= ATTACH database_kw_opt expr AS expr key_opt",
- /* 303 */ "cmd ::= DETACH database_kw_opt expr",
- /* 304 */ "key_opt ::=",
- /* 305 */ "key_opt ::= KEY expr",
- /* 306 */ "database_kw_opt ::= DATABASE",
- /* 307 */ "database_kw_opt ::=",
- /* 308 */ "cmd ::= REINDEX",
- /* 309 */ "cmd ::= REINDEX nm dbnm",
- /* 310 */ "cmd ::= ANALYZE",
- /* 311 */ "cmd ::= ANALYZE nm dbnm",
- /* 312 */ "cmd ::= ALTER TABLE fullname RENAME TO nm",
- /* 313 */ "cmd ::= ALTER TABLE add_column_fullname ADD kwcolumn_opt column",
- /* 314 */ "add_column_fullname ::= fullname",
- /* 315 */ "kwcolumn_opt ::=",
- /* 316 */ "kwcolumn_opt ::= COLUMNKW",
- /* 317 */ "cmd ::= create_vtab",
- /* 318 */ "cmd ::= create_vtab LP vtabarglist RP",
- /* 319 */ "create_vtab ::= createkw VIRTUAL TABLE nm dbnm USING nm",
- /* 320 */ "vtabarglist ::= vtabarg",
- /* 321 */ "vtabarglist ::= vtabarglist COMMA vtabarg",
- /* 322 */ "vtabarg ::=",
- /* 323 */ "vtabarg ::= vtabarg vtabargtoken",
- /* 324 */ "vtabargtoken ::= ANY",
- /* 325 */ "vtabargtoken ::= lp anylist RP",
- /* 326 */ "lp ::= LP",
- /* 327 */ "anylist ::=",
- /* 328 */ "anylist ::= anylist LP anylist RP",
- /* 329 */ "anylist ::= anylist ANY",
+ /* 212 */ "expr ::= expr likeop expr",
+ /* 213 */ "expr ::= expr likeop expr ESCAPE expr",
+ /* 214 */ "expr ::= expr ISNULL|NOTNULL",
+ /* 215 */ "expr ::= expr NOT NULL",
+ /* 216 */ "expr ::= expr IS expr",
+ /* 217 */ "expr ::= expr IS NOT expr",
+ /* 218 */ "expr ::= NOT expr",
+ /* 219 */ "expr ::= BITNOT expr",
+ /* 220 */ "expr ::= MINUS expr",
+ /* 221 */ "expr ::= PLUS expr",
+ /* 222 */ "between_op ::= BETWEEN",
+ /* 223 */ "between_op ::= NOT BETWEEN",
+ /* 224 */ "expr ::= expr between_op expr AND expr",
+ /* 225 */ "in_op ::= IN",
+ /* 226 */ "in_op ::= NOT IN",
+ /* 227 */ "expr ::= expr in_op LP exprlist RP",
+ /* 228 */ "expr ::= LP select RP",
+ /* 229 */ "expr ::= expr in_op LP select RP",
+ /* 230 */ "expr ::= expr in_op nm dbnm",
+ /* 231 */ "expr ::= EXISTS LP select RP",
+ /* 232 */ "expr ::= CASE case_operand case_exprlist case_else END",
+ /* 233 */ "case_exprlist ::= case_exprlist WHEN expr THEN expr",
+ /* 234 */ "case_exprlist ::= WHEN expr THEN expr",
+ /* 235 */ "case_else ::= ELSE expr",
+ /* 236 */ "case_else ::=",
+ /* 237 */ "case_operand ::= expr",
+ /* 238 */ "case_operand ::=",
+ /* 239 */ "exprlist ::= nexprlist",
+ /* 240 */ "exprlist ::=",
+ /* 241 */ "nexprlist ::= nexprlist COMMA expr",
+ /* 242 */ "nexprlist ::= expr",
+ /* 243 */ "cmd ::= createkw uniqueflag INDEX ifnotexists nm dbnm ON nm LP idxlist RP",
+ /* 244 */ "uniqueflag ::= UNIQUE",
+ /* 245 */ "uniqueflag ::=",
+ /* 246 */ "idxlist_opt ::=",
+ /* 247 */ "idxlist_opt ::= LP idxlist RP",
+ /* 248 */ "idxlist ::= idxlist COMMA nm collate sortorder",
+ /* 249 */ "idxlist ::= nm collate sortorder",
+ /* 250 */ "collate ::=",
+ /* 251 */ "collate ::= COLLATE ids",
+ /* 252 */ "cmd ::= DROP INDEX ifexists fullname",
+ /* 253 */ "cmd ::= VACUUM",
+ /* 254 */ "cmd ::= VACUUM nm",
+ /* 255 */ "cmd ::= PRAGMA nm dbnm",
+ /* 256 */ "cmd ::= PRAGMA nm dbnm EQ nmnum",
+ /* 257 */ "cmd ::= PRAGMA nm dbnm LP nmnum RP",
+ /* 258 */ "cmd ::= PRAGMA nm dbnm EQ minus_num",
+ /* 259 */ "cmd ::= PRAGMA nm dbnm LP minus_num RP",
+ /* 260 */ "nmnum ::= plus_num",
+ /* 261 */ "nmnum ::= nm",
+ /* 262 */ "nmnum ::= ON",
+ /* 263 */ "nmnum ::= DELETE",
+ /* 264 */ "nmnum ::= DEFAULT",
+ /* 265 */ "plus_num ::= plus_opt number",
+ /* 266 */ "minus_num ::= MINUS number",
+ /* 267 */ "number ::= INTEGER|FLOAT",
+ /* 268 */ "plus_opt ::= PLUS",
+ /* 269 */ "plus_opt ::=",
+ /* 270 */ "cmd ::= createkw trigger_decl BEGIN trigger_cmd_list END",
+ /* 271 */ "trigger_decl ::= temp TRIGGER ifnotexists nm dbnm trigger_time trigger_event ON fullname foreach_clause when_clause",
+ /* 272 */ "trigger_time ::= BEFORE",
+ /* 273 */ "trigger_time ::= AFTER",
+ /* 274 */ "trigger_time ::= INSTEAD OF",
+ /* 275 */ "trigger_time ::=",
+ /* 276 */ "trigger_event ::= DELETE|INSERT",
+ /* 277 */ "trigger_event ::= UPDATE",
+ /* 278 */ "trigger_event ::= UPDATE OF inscollist",
+ /* 279 */ "foreach_clause ::=",
+ /* 280 */ "foreach_clause ::= FOR EACH ROW",
+ /* 281 */ "when_clause ::=",
+ /* 282 */ "when_clause ::= WHEN expr",
+ /* 283 */ "trigger_cmd_list ::= trigger_cmd_list trigger_cmd SEMI",
+ /* 284 */ "trigger_cmd_list ::= trigger_cmd SEMI",
+ /* 285 */ "trnm ::= nm",
+ /* 286 */ "trnm ::= nm DOT nm",
+ /* 287 */ "tridxby ::=",
+ /* 288 */ "tridxby ::= INDEXED BY nm",
+ /* 289 */ "tridxby ::= NOT INDEXED",
+ /* 290 */ "trigger_cmd ::= UPDATE orconf trnm tridxby SET setlist where_opt",
+ /* 291 */ "trigger_cmd ::= insert_cmd INTO trnm inscollist_opt VALUES LP itemlist RP",
+ /* 292 */ "trigger_cmd ::= insert_cmd INTO trnm inscollist_opt select",
+ /* 293 */ "trigger_cmd ::= DELETE FROM trnm tridxby where_opt",
+ /* 294 */ "trigger_cmd ::= select",
+ /* 295 */ "expr ::= RAISE LP IGNORE RP",
+ /* 296 */ "expr ::= RAISE LP raisetype COMMA nm RP",
+ /* 297 */ "raisetype ::= ROLLBACK",
+ /* 298 */ "raisetype ::= ABORT",
+ /* 299 */ "raisetype ::= FAIL",
+ /* 300 */ "cmd ::= DROP TRIGGER ifexists fullname",
+ /* 301 */ "cmd ::= ATTACH database_kw_opt expr AS expr key_opt",
+ /* 302 */ "cmd ::= DETACH database_kw_opt expr",
+ /* 303 */ "key_opt ::=",
+ /* 304 */ "key_opt ::= KEY expr",
+ /* 305 */ "database_kw_opt ::= DATABASE",
+ /* 306 */ "database_kw_opt ::=",
+ /* 307 */ "cmd ::= REINDEX",
+ /* 308 */ "cmd ::= REINDEX nm dbnm",
+ /* 309 */ "cmd ::= ANALYZE",
+ /* 310 */ "cmd ::= ANALYZE nm dbnm",
+ /* 311 */ "cmd ::= ALTER TABLE fullname RENAME TO nm",
+ /* 312 */ "cmd ::= ALTER TABLE add_column_fullname ADD kwcolumn_opt column",
+ /* 313 */ "add_column_fullname ::= fullname",
+ /* 314 */ "kwcolumn_opt ::=",
+ /* 315 */ "kwcolumn_opt ::= COLUMNKW",
+ /* 316 */ "cmd ::= create_vtab",
+ /* 317 */ "cmd ::= create_vtab LP vtabarglist RP",
+ /* 318 */ "create_vtab ::= createkw VIRTUAL TABLE nm dbnm USING nm",
+ /* 319 */ "vtabarglist ::= vtabarg",
+ /* 320 */ "vtabarglist ::= vtabarglist COMMA vtabarg",
+ /* 321 */ "vtabarg ::=",
+ /* 322 */ "vtabarg ::= vtabarg vtabargtoken",
+ /* 323 */ "vtabargtoken ::= ANY",
+ /* 324 */ "vtabargtoken ::= lp anylist RP",
+ /* 325 */ "lp ::= LP",
+ /* 326 */ "anylist ::=",
+ /* 327 */ "anylist ::= anylist LP anylist RP",
+ /* 328 */ "anylist ::= anylist ANY",
 };
 #endif /* NDEBUG */
 
@@ -98898,14 +100719,13 @@
     case 160: /* select */
     case 194: /* oneselect */
 {
-sqlite3SelectDelete(pParse->db, (yypminor->yy3));
+sqlite3SelectDelete(pParse->db, (yypminor->yy387));
 }
       break;
     case 174: /* term */
     case 175: /* expr */
-    case 223: /* escape */
 {
-sqlite3ExprDelete(pParse->db, (yypminor->yy346).pExpr);
+sqlite3ExprDelete(pParse->db, (yypminor->yy118).pExpr);
 }
       break;
     case 179: /* idxlist_opt */
@@ -98919,9 +100739,9 @@
     case 217: /* setlist */
     case 220: /* itemlist */
     case 221: /* exprlist */
-    case 227: /* case_exprlist */
+    case 226: /* case_exprlist */
 {
-sqlite3ExprListDelete(pParse->db, (yypminor->yy14));
+sqlite3ExprListDelete(pParse->db, (yypminor->yy322));
 }
       break;
     case 193: /* fullname */
@@ -98929,37 +100749,37 @@
     case 206: /* seltablist */
     case 207: /* stl_prefix */
 {
-sqlite3SrcListDelete(pParse->db, (yypminor->yy65));
+sqlite3SrcListDelete(pParse->db, (yypminor->yy259));
 }
       break;
     case 199: /* where_opt */
     case 201: /* having_opt */
     case 210: /* on_opt */
     case 215: /* sortitem */
-    case 226: /* case_operand */
-    case 228: /* case_else */
-    case 239: /* when_clause */
-    case 244: /* key_opt */
+    case 225: /* case_operand */
+    case 227: /* case_else */
+    case 238: /* when_clause */
+    case 243: /* key_opt */
 {
-sqlite3ExprDelete(pParse->db, (yypminor->yy132));
+sqlite3ExprDelete(pParse->db, (yypminor->yy314));
 }
       break;
     case 211: /* using_opt */
     case 213: /* inscollist */
     case 219: /* inscollist_opt */
 {
-sqlite3IdListDelete(pParse->db, (yypminor->yy408));
+sqlite3IdListDelete(pParse->db, (yypminor->yy384));
 }
       break;
-    case 235: /* trigger_cmd_list */
-    case 240: /* trigger_cmd */
+    case 234: /* trigger_cmd_list */
+    case 239: /* trigger_cmd */
 {
-sqlite3DeleteTriggerStep(pParse->db, (yypminor->yy473));
+sqlite3DeleteTriggerStep(pParse->db, (yypminor->yy203));
 }
       break;
-    case 237: /* trigger_event */
+    case 236: /* trigger_event */
 {
-sqlite3IdListDelete(pParse->db, (yypminor->yy378).b);
+sqlite3IdListDelete(pParse->db, (yypminor->yy90).b);
 }
       break;
     default:  break;   /* If no destructor action specified: do nothing */
@@ -99417,47 +101237,46 @@
   { 222, 2 },
   { 222, 1 },
   { 222, 2 },
+  { 175, 3 },
+  { 175, 5 },
+  { 175, 2 },
+  { 175, 3 },
+  { 175, 3 },
+  { 175, 4 },
+  { 175, 2 },
+  { 175, 2 },
+  { 175, 2 },
+  { 175, 2 },
+  { 223, 1 },
   { 223, 2 },
-  { 223, 0 },
-  { 175, 4 },
-  { 175, 2 },
-  { 175, 3 },
-  { 175, 3 },
-  { 175, 4 },
-  { 175, 2 },
-  { 175, 2 },
-  { 175, 2 },
-  { 175, 2 },
+  { 175, 5 },
   { 224, 1 },
   { 224, 2 },
   { 175, 5 },
-  { 225, 1 },
-  { 225, 2 },
-  { 175, 5 },
   { 175, 3 },
   { 175, 5 },
   { 175, 4 },
   { 175, 4 },
   { 175, 5 },
-  { 227, 5 },
-  { 227, 4 },
-  { 228, 2 },
-  { 228, 0 },
-  { 226, 1 },
-  { 226, 0 },
+  { 226, 5 },
+  { 226, 4 },
+  { 227, 2 },
+  { 227, 0 },
+  { 225, 1 },
+  { 225, 0 },
   { 221, 1 },
   { 221, 0 },
   { 216, 3 },
   { 216, 1 },
   { 147, 11 },
-  { 229, 1 },
-  { 229, 0 },
+  { 228, 1 },
+  { 228, 0 },
   { 179, 0 },
   { 179, 3 },
   { 187, 5 },
   { 187, 3 },
-  { 230, 0 },
-  { 230, 2 },
+  { 229, 0 },
+  { 229, 2 },
   { 147, 4 },
   { 147, 1 },
   { 147, 2 },
@@ -99466,41 +101285,41 @@
   { 147, 6 },
   { 147, 5 },
   { 147, 6 },
-  { 231, 1 },
-  { 231, 1 },
-  { 231, 1 },
-  { 231, 1 },
-  { 231, 1 },
+  { 230, 1 },
+  { 230, 1 },
+  { 230, 1 },
+  { 230, 1 },
+  { 230, 1 },
   { 170, 2 },
   { 171, 2 },
-  { 233, 1 },
   { 232, 1 },
-  { 232, 0 },
+  { 231, 1 },
+  { 231, 0 },
   { 147, 5 },
-  { 234, 11 },
+  { 233, 11 },
+  { 235, 1 },
+  { 235, 1 },
+  { 235, 2 },
+  { 235, 0 },
   { 236, 1 },
   { 236, 1 },
-  { 236, 2 },
-  { 236, 0 },
-  { 237, 1 },
-  { 237, 1 },
+  { 236, 3 },
+  { 237, 0 },
   { 237, 3 },
   { 238, 0 },
-  { 238, 3 },
-  { 239, 0 },
-  { 239, 2 },
-  { 235, 3 },
-  { 235, 2 },
-  { 241, 1 },
-  { 241, 3 },
-  { 242, 0 },
-  { 242, 3 },
-  { 242, 2 },
-  { 240, 7 },
-  { 240, 8 },
-  { 240, 5 },
-  { 240, 5 },
+  { 238, 2 },
+  { 234, 3 },
+  { 234, 2 },
   { 240, 1 },
+  { 240, 3 },
+  { 241, 0 },
+  { 241, 3 },
+  { 241, 2 },
+  { 239, 7 },
+  { 239, 8 },
+  { 239, 5 },
+  { 239, 5 },
+  { 239, 1 },
   { 175, 4 },
   { 175, 6 },
   { 191, 1 },
@@ -99509,32 +101328,32 @@
   { 147, 4 },
   { 147, 6 },
   { 147, 3 },
-  { 244, 0 },
-  { 244, 2 },
-  { 243, 1 },
   { 243, 0 },
+  { 243, 2 },
+  { 242, 1 },
+  { 242, 0 },
   { 147, 1 },
   { 147, 3 },
   { 147, 1 },
   { 147, 3 },
   { 147, 6 },
   { 147, 6 },
+  { 244, 1 },
+  { 245, 0 },
   { 245, 1 },
-  { 246, 0 },
-  { 246, 1 },
   { 147, 1 },
   { 147, 4 },
-  { 247, 7 },
-  { 248, 1 },
-  { 248, 3 },
-  { 249, 0 },
-  { 249, 2 },
+  { 246, 7 },
+  { 247, 1 },
+  { 247, 3 },
+  { 248, 0 },
+  { 248, 2 },
+  { 249, 1 },
+  { 249, 3 },
   { 250, 1 },
-  { 250, 3 },
-  { 251, 1 },
-  { 252, 0 },
-  { 252, 4 },
-  { 252, 2 },
+  { 251, 0 },
+  { 251, 4 },
+  { 251, 2 },
 };
 
 static void yy_accept(yyParser*);  /* Forward Declaration */
@@ -99602,17 +101421,17 @@
 { sqlite3FinishCoding(pParse); }
         break;
       case 9: /* cmd ::= BEGIN transtype trans_opt */
-{sqlite3BeginTransaction(pParse, yymsp[-1].minor.yy328);}
+{sqlite3BeginTransaction(pParse, yymsp[-1].minor.yy4);}
         break;
       case 13: /* transtype ::= */
-{yygotominor.yy328 = TK_DEFERRED;}
+{yygotominor.yy4 = TK_DEFERRED;}
         break;
       case 14: /* transtype ::= DEFERRED */
       case 15: /* transtype ::= IMMEDIATE */ yytestcase(yyruleno==15);
       case 16: /* transtype ::= EXCLUSIVE */ yytestcase(yyruleno==16);
       case 115: /* multiselect_op ::= UNION */ yytestcase(yyruleno==115);
       case 117: /* multiselect_op ::= EXCEPT|INTERSECT */ yytestcase(yyruleno==117);
-{yygotominor.yy328 = yymsp[0].major;}
+{yygotominor.yy4 = yymsp[0].major;}
         break;
       case 17: /* cmd ::= COMMIT trans_opt */
       case 18: /* cmd ::= END trans_opt */ yytestcase(yyruleno==18);
@@ -99638,7 +101457,7 @@
         break;
       case 26: /* create_table ::= createkw temp TABLE ifnotexists nm dbnm */
 {
-   sqlite3StartTable(pParse,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy0,yymsp[-4].minor.yy328,0,0,yymsp[-2].minor.yy328);
+   sqlite3StartTable(pParse,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy0,yymsp[-4].minor.yy4,0,0,yymsp[-2].minor.yy4);
 }
         break;
       case 27: /* createkw ::= CREATE */
@@ -99657,9 +101476,9 @@
       case 109: /* ifexists ::= */ yytestcase(yyruleno==109);
       case 120: /* distinct ::= ALL */ yytestcase(yyruleno==120);
       case 121: /* distinct ::= */ yytestcase(yyruleno==121);
-      case 223: /* between_op ::= BETWEEN */ yytestcase(yyruleno==223);
-      case 226: /* in_op ::= IN */ yytestcase(yyruleno==226);
-{yygotominor.yy328 = 0;}
+      case 222: /* between_op ::= BETWEEN */ yytestcase(yyruleno==222);
+      case 225: /* in_op ::= IN */ yytestcase(yyruleno==225);
+{yygotominor.yy4 = 0;}
         break;
       case 29: /* ifnotexists ::= IF NOT EXISTS */
       case 30: /* temp ::= TEMP */ yytestcase(yyruleno==30);
@@ -99667,9 +101486,9 @@
       case 86: /* init_deferred_pred_opt ::= INITIALLY DEFERRED */ yytestcase(yyruleno==86);
       case 108: /* ifexists ::= IF EXISTS */ yytestcase(yyruleno==108);
       case 119: /* distinct ::= DISTINCT */ yytestcase(yyruleno==119);
-      case 224: /* between_op ::= NOT BETWEEN */ yytestcase(yyruleno==224);
-      case 227: /* in_op ::= NOT IN */ yytestcase(yyruleno==227);
-{yygotominor.yy328 = 1;}
+      case 223: /* between_op ::= NOT BETWEEN */ yytestcase(yyruleno==223);
+      case 226: /* in_op ::= NOT IN */ yytestcase(yyruleno==226);
+{yygotominor.yy4 = 1;}
         break;
       case 32: /* create_table_args ::= LP columnlist conslist_opt RP */
 {
@@ -99678,8 +101497,8 @@
         break;
       case 33: /* create_table_args ::= AS select */
 {
-  sqlite3EndTable(pParse,0,0,yymsp[0].minor.yy3);
-  sqlite3SelectDelete(pParse->db, yymsp[0].minor.yy3);
+  sqlite3EndTable(pParse,0,0,yymsp[0].minor.yy387);
+  sqlite3SelectDelete(pParse->db, yymsp[0].minor.yy387);
 }
         break;
       case 36: /* column ::= columnid type carglist */
@@ -99706,16 +101525,16 @@
       case 128: /* as ::= ids */ yytestcase(yyruleno==128);
       case 138: /* dbnm ::= DOT nm */ yytestcase(yyruleno==138);
       case 147: /* indexed_opt ::= INDEXED BY nm */ yytestcase(yyruleno==147);
-      case 252: /* collate ::= COLLATE ids */ yytestcase(yyruleno==252);
-      case 261: /* nmnum ::= plus_num */ yytestcase(yyruleno==261);
-      case 262: /* nmnum ::= nm */ yytestcase(yyruleno==262);
-      case 263: /* nmnum ::= ON */ yytestcase(yyruleno==263);
-      case 264: /* nmnum ::= DELETE */ yytestcase(yyruleno==264);
-      case 265: /* nmnum ::= DEFAULT */ yytestcase(yyruleno==265);
-      case 266: /* plus_num ::= plus_opt number */ yytestcase(yyruleno==266);
-      case 267: /* minus_num ::= MINUS number */ yytestcase(yyruleno==267);
-      case 268: /* number ::= INTEGER|FLOAT */ yytestcase(yyruleno==268);
-      case 286: /* trnm ::= nm */ yytestcase(yyruleno==286);
+      case 251: /* collate ::= COLLATE ids */ yytestcase(yyruleno==251);
+      case 260: /* nmnum ::= plus_num */ yytestcase(yyruleno==260);
+      case 261: /* nmnum ::= nm */ yytestcase(yyruleno==261);
+      case 262: /* nmnum ::= ON */ yytestcase(yyruleno==262);
+      case 263: /* nmnum ::= DELETE */ yytestcase(yyruleno==263);
+      case 264: /* nmnum ::= DEFAULT */ yytestcase(yyruleno==264);
+      case 265: /* plus_num ::= plus_opt number */ yytestcase(yyruleno==265);
+      case 266: /* minus_num ::= MINUS number */ yytestcase(yyruleno==266);
+      case 267: /* number ::= INTEGER|FLOAT */ yytestcase(yyruleno==267);
+      case 285: /* trnm ::= nm */ yytestcase(yyruleno==285);
 {yygotominor.yy0 = yymsp[0].minor.yy0;}
         break;
       case 45: /* type ::= typetoken */
@@ -99738,17 +101557,17 @@
         break;
       case 57: /* ccons ::= DEFAULT term */
       case 59: /* ccons ::= DEFAULT PLUS term */ yytestcase(yyruleno==59);
-{sqlite3AddDefaultValue(pParse,&yymsp[0].minor.yy346);}
+{sqlite3AddDefaultValue(pParse,&yymsp[0].minor.yy118);}
         break;
       case 58: /* ccons ::= DEFAULT LP expr RP */
-{sqlite3AddDefaultValue(pParse,&yymsp[-1].minor.yy346);}
+{sqlite3AddDefaultValue(pParse,&yymsp[-1].minor.yy118);}
         break;
       case 60: /* ccons ::= DEFAULT MINUS term */
 {
   ExprSpan v;
-  v.pExpr = sqlite3PExpr(pParse, TK_UMINUS, yymsp[0].minor.yy346.pExpr, 0, 0);
+  v.pExpr = sqlite3PExpr(pParse, TK_UMINUS, yymsp[0].minor.yy118.pExpr, 0, 0);
   v.zStart = yymsp[-1].minor.yy0.z;
-  v.zEnd = yymsp[0].minor.yy346.zEnd;
+  v.zEnd = yymsp[0].minor.yy118.zEnd;
   sqlite3AddDefaultValue(pParse,&v);
 }
         break;
@@ -99760,62 +101579,62 @@
 }
         break;
       case 63: /* ccons ::= NOT NULL onconf */
-{sqlite3AddNotNull(pParse, yymsp[0].minor.yy328);}
+{sqlite3AddNotNull(pParse, yymsp[0].minor.yy4);}
         break;
       case 64: /* ccons ::= PRIMARY KEY sortorder onconf autoinc */
-{sqlite3AddPrimaryKey(pParse,0,yymsp[-1].minor.yy328,yymsp[0].minor.yy328,yymsp[-2].minor.yy328);}
+{sqlite3AddPrimaryKey(pParse,0,yymsp[-1].minor.yy4,yymsp[0].minor.yy4,yymsp[-2].minor.yy4);}
         break;
       case 65: /* ccons ::= UNIQUE onconf */
-{sqlite3CreateIndex(pParse,0,0,0,0,yymsp[0].minor.yy328,0,0,0,0);}
+{sqlite3CreateIndex(pParse,0,0,0,0,yymsp[0].minor.yy4,0,0,0,0);}
         break;
       case 66: /* ccons ::= CHECK LP expr RP */
-{sqlite3AddCheckConstraint(pParse,yymsp[-1].minor.yy346.pExpr);}
+{sqlite3AddCheckConstraint(pParse,yymsp[-1].minor.yy118.pExpr);}
         break;
       case 67: /* ccons ::= REFERENCES nm idxlist_opt refargs */
-{sqlite3CreateForeignKey(pParse,0,&yymsp[-2].minor.yy0,yymsp[-1].minor.yy14,yymsp[0].minor.yy328);}
+{sqlite3CreateForeignKey(pParse,0,&yymsp[-2].minor.yy0,yymsp[-1].minor.yy322,yymsp[0].minor.yy4);}
         break;
       case 68: /* ccons ::= defer_subclause */
-{sqlite3DeferForeignKey(pParse,yymsp[0].minor.yy328);}
+{sqlite3DeferForeignKey(pParse,yymsp[0].minor.yy4);}
         break;
       case 69: /* ccons ::= COLLATE ids */
 {sqlite3AddCollateType(pParse, &yymsp[0].minor.yy0);}
         break;
       case 72: /* refargs ::= */
-{ yygotominor.yy328 = OE_None*0x0101; /* EV: R-19803-45884 */}
+{ yygotominor.yy4 = OE_None*0x0101; /* EV: R-19803-45884 */}
         break;
       case 73: /* refargs ::= refargs refarg */
-{ yygotominor.yy328 = (yymsp[-1].minor.yy328 & ~yymsp[0].minor.yy429.mask) | yymsp[0].minor.yy429.value; }
+{ yygotominor.yy4 = (yymsp[-1].minor.yy4 & ~yymsp[0].minor.yy215.mask) | yymsp[0].minor.yy215.value; }
         break;
       case 74: /* refarg ::= MATCH nm */
       case 75: /* refarg ::= ON INSERT refact */ yytestcase(yyruleno==75);
-{ yygotominor.yy429.value = 0;     yygotominor.yy429.mask = 0x000000; }
+{ yygotominor.yy215.value = 0;     yygotominor.yy215.mask = 0x000000; }
         break;
       case 76: /* refarg ::= ON DELETE refact */
-{ yygotominor.yy429.value = yymsp[0].minor.yy328;     yygotominor.yy429.mask = 0x0000ff; }
+{ yygotominor.yy215.value = yymsp[0].minor.yy4;     yygotominor.yy215.mask = 0x0000ff; }
         break;
       case 77: /* refarg ::= ON UPDATE refact */
-{ yygotominor.yy429.value = yymsp[0].minor.yy328<<8;  yygotominor.yy429.mask = 0x00ff00; }
+{ yygotominor.yy215.value = yymsp[0].minor.yy4<<8;  yygotominor.yy215.mask = 0x00ff00; }
         break;
       case 78: /* refact ::= SET NULL */
-{ yygotominor.yy328 = OE_SetNull;  /* EV: R-33326-45252 */}
+{ yygotominor.yy4 = OE_SetNull;  /* EV: R-33326-45252 */}
         break;
       case 79: /* refact ::= SET DEFAULT */
-{ yygotominor.yy328 = OE_SetDflt;  /* EV: R-33326-45252 */}
+{ yygotominor.yy4 = OE_SetDflt;  /* EV: R-33326-45252 */}
         break;
       case 80: /* refact ::= CASCADE */
-{ yygotominor.yy328 = OE_Cascade;  /* EV: R-33326-45252 */}
+{ yygotominor.yy4 = OE_Cascade;  /* EV: R-33326-45252 */}
         break;
       case 81: /* refact ::= RESTRICT */
-{ yygotominor.yy328 = OE_Restrict; /* EV: R-33326-45252 */}
+{ yygotominor.yy4 = OE_Restrict; /* EV: R-33326-45252 */}
         break;
       case 82: /* refact ::= NO ACTION */
-{ yygotominor.yy328 = OE_None;     /* EV: R-33326-45252 */}
+{ yygotominor.yy4 = OE_None;     /* EV: R-33326-45252 */}
         break;
       case 84: /* defer_subclause ::= DEFERRABLE init_deferred_pred_opt */
       case 99: /* defer_subclause_opt ::= defer_subclause */ yytestcase(yyruleno==99);
       case 101: /* onconf ::= ON CONFLICT resolvetype */ yytestcase(yyruleno==101);
       case 104: /* resolvetype ::= raisetype */ yytestcase(yyruleno==104);
-{yygotominor.yy328 = yymsp[0].minor.yy328;}
+{yygotominor.yy4 = yymsp[0].minor.yy4;}
         break;
       case 88: /* conslist_opt ::= */
 {yygotominor.yy0.n = 0; yygotominor.yy0.z = 0;}
@@ -99824,101 +101643,101 @@
 {yygotominor.yy0 = yymsp[-1].minor.yy0;}
         break;
       case 94: /* tcons ::= PRIMARY KEY LP idxlist autoinc RP onconf */
-{sqlite3AddPrimaryKey(pParse,yymsp[-3].minor.yy14,yymsp[0].minor.yy328,yymsp[-2].minor.yy328,0);}
+{sqlite3AddPrimaryKey(pParse,yymsp[-3].minor.yy322,yymsp[0].minor.yy4,yymsp[-2].minor.yy4,0);}
         break;
       case 95: /* tcons ::= UNIQUE LP idxlist RP onconf */
-{sqlite3CreateIndex(pParse,0,0,0,yymsp[-2].minor.yy14,yymsp[0].minor.yy328,0,0,0,0);}
+{sqlite3CreateIndex(pParse,0,0,0,yymsp[-2].minor.yy322,yymsp[0].minor.yy4,0,0,0,0);}
         break;
       case 96: /* tcons ::= CHECK LP expr RP onconf */
-{sqlite3AddCheckConstraint(pParse,yymsp[-2].minor.yy346.pExpr);}
+{sqlite3AddCheckConstraint(pParse,yymsp[-2].minor.yy118.pExpr);}
         break;
       case 97: /* tcons ::= FOREIGN KEY LP idxlist RP REFERENCES nm idxlist_opt refargs defer_subclause_opt */
 {
-    sqlite3CreateForeignKey(pParse, yymsp[-6].minor.yy14, &yymsp[-3].minor.yy0, yymsp[-2].minor.yy14, yymsp[-1].minor.yy328);
-    sqlite3DeferForeignKey(pParse, yymsp[0].minor.yy328);
+    sqlite3CreateForeignKey(pParse, yymsp[-6].minor.yy322, &yymsp[-3].minor.yy0, yymsp[-2].minor.yy322, yymsp[-1].minor.yy4);
+    sqlite3DeferForeignKey(pParse, yymsp[0].minor.yy4);
 }
         break;
       case 100: /* onconf ::= */
-{yygotominor.yy328 = OE_Default;}
+{yygotominor.yy4 = OE_Default;}
         break;
       case 102: /* orconf ::= */
-{yygotominor.yy186 = OE_Default;}
+{yygotominor.yy210 = OE_Default;}
         break;
       case 103: /* orconf ::= OR resolvetype */
-{yygotominor.yy186 = (u8)yymsp[0].minor.yy328;}
+{yygotominor.yy210 = (u8)yymsp[0].minor.yy4;}
         break;
       case 105: /* resolvetype ::= IGNORE */
-{yygotominor.yy328 = OE_Ignore;}
+{yygotominor.yy4 = OE_Ignore;}
         break;
       case 106: /* resolvetype ::= REPLACE */
-{yygotominor.yy328 = OE_Replace;}
+{yygotominor.yy4 = OE_Replace;}
         break;
       case 107: /* cmd ::= DROP TABLE ifexists fullname */
 {
-  sqlite3DropTable(pParse, yymsp[0].minor.yy65, 0, yymsp[-1].minor.yy328);
+  sqlite3DropTable(pParse, yymsp[0].minor.yy259, 0, yymsp[-1].minor.yy4);
 }
         break;
       case 110: /* cmd ::= createkw temp VIEW ifnotexists nm dbnm AS select */
 {
-  sqlite3CreateView(pParse, &yymsp[-7].minor.yy0, &yymsp[-3].minor.yy0, &yymsp[-2].minor.yy0, yymsp[0].minor.yy3, yymsp[-6].minor.yy328, yymsp[-4].minor.yy328);
+  sqlite3CreateView(pParse, &yymsp[-7].minor.yy0, &yymsp[-3].minor.yy0, &yymsp[-2].minor.yy0, yymsp[0].minor.yy387, yymsp[-6].minor.yy4, yymsp[-4].minor.yy4);
 }
         break;
       case 111: /* cmd ::= DROP VIEW ifexists fullname */
 {
-  sqlite3DropTable(pParse, yymsp[0].minor.yy65, 1, yymsp[-1].minor.yy328);
+  sqlite3DropTable(pParse, yymsp[0].minor.yy259, 1, yymsp[-1].minor.yy4);
 }
         break;
       case 112: /* cmd ::= select */
 {
   SelectDest dest = {SRT_Output, 0, 0, 0, 0};
-  sqlite3Select(pParse, yymsp[0].minor.yy3, &dest);
-  sqlite3SelectDelete(pParse->db, yymsp[0].minor.yy3);
+  sqlite3Select(pParse, yymsp[0].minor.yy387, &dest);
+  sqlite3SelectDelete(pParse->db, yymsp[0].minor.yy387);
 }
         break;
       case 113: /* select ::= oneselect */
-{yygotominor.yy3 = yymsp[0].minor.yy3;}
+{yygotominor.yy387 = yymsp[0].minor.yy387;}
         break;
       case 114: /* select ::= select multiselect_op oneselect */
 {
-  if( yymsp[0].minor.yy3 ){
-    yymsp[0].minor.yy3->op = (u8)yymsp[-1].minor.yy328;
-    yymsp[0].minor.yy3->pPrior = yymsp[-2].minor.yy3;
+  if( yymsp[0].minor.yy387 ){
+    yymsp[0].minor.yy387->op = (u8)yymsp[-1].minor.yy4;
+    yymsp[0].minor.yy387->pPrior = yymsp[-2].minor.yy387;
   }else{
-    sqlite3SelectDelete(pParse->db, yymsp[-2].minor.yy3);
+    sqlite3SelectDelete(pParse->db, yymsp[-2].minor.yy387);
   }
-  yygotominor.yy3 = yymsp[0].minor.yy3;
+  yygotominor.yy387 = yymsp[0].minor.yy387;
 }
         break;
       case 116: /* multiselect_op ::= UNION ALL */
-{yygotominor.yy328 = TK_ALL;}
+{yygotominor.yy4 = TK_ALL;}
         break;
       case 118: /* oneselect ::= SELECT distinct selcollist from where_opt groupby_opt having_opt orderby_opt limit_opt */
 {
-  yygotominor.yy3 = sqlite3SelectNew(pParse,yymsp[-6].minor.yy14,yymsp[-5].minor.yy65,yymsp[-4].minor.yy132,yymsp[-3].minor.yy14,yymsp[-2].minor.yy132,yymsp[-1].minor.yy14,yymsp[-7].minor.yy328,yymsp[0].minor.yy476.pLimit,yymsp[0].minor.yy476.pOffset);
+  yygotominor.yy387 = sqlite3SelectNew(pParse,yymsp[-6].minor.yy322,yymsp[-5].minor.yy259,yymsp[-4].minor.yy314,yymsp[-3].minor.yy322,yymsp[-2].minor.yy314,yymsp[-1].minor.yy322,yymsp[-7].minor.yy4,yymsp[0].minor.yy292.pLimit,yymsp[0].minor.yy292.pOffset);
 }
         break;
       case 122: /* sclp ::= selcollist COMMA */
-      case 248: /* idxlist_opt ::= LP idxlist RP */ yytestcase(yyruleno==248);
-{yygotominor.yy14 = yymsp[-1].minor.yy14;}
+      case 247: /* idxlist_opt ::= LP idxlist RP */ yytestcase(yyruleno==247);
+{yygotominor.yy322 = yymsp[-1].minor.yy322;}
         break;
       case 123: /* sclp ::= */
       case 151: /* orderby_opt ::= */ yytestcase(yyruleno==151);
       case 159: /* groupby_opt ::= */ yytestcase(yyruleno==159);
-      case 241: /* exprlist ::= */ yytestcase(yyruleno==241);
-      case 247: /* idxlist_opt ::= */ yytestcase(yyruleno==247);
-{yygotominor.yy14 = 0;}
+      case 240: /* exprlist ::= */ yytestcase(yyruleno==240);
+      case 246: /* idxlist_opt ::= */ yytestcase(yyruleno==246);
+{yygotominor.yy322 = 0;}
         break;
       case 124: /* selcollist ::= sclp expr as */
 {
-   yygotominor.yy14 = sqlite3ExprListAppend(pParse, yymsp[-2].minor.yy14, yymsp[-1].minor.yy346.pExpr);
-   if( yymsp[0].minor.yy0.n>0 ) sqlite3ExprListSetName(pParse, yygotominor.yy14, &yymsp[0].minor.yy0, 1);
-   sqlite3ExprListSetSpan(pParse,yygotominor.yy14,&yymsp[-1].minor.yy346);
+   yygotominor.yy322 = sqlite3ExprListAppend(pParse, yymsp[-2].minor.yy322, yymsp[-1].minor.yy118.pExpr);
+   if( yymsp[0].minor.yy0.n>0 ) sqlite3ExprListSetName(pParse, yygotominor.yy322, &yymsp[0].minor.yy0, 1);
+   sqlite3ExprListSetSpan(pParse,yygotominor.yy322,&yymsp[-1].minor.yy118);
 }
         break;
       case 125: /* selcollist ::= sclp STAR */
 {
   Expr *p = sqlite3Expr(pParse->db, TK_ALL, 0);
-  yygotominor.yy14 = sqlite3ExprListAppend(pParse, yymsp[-1].minor.yy14, p);
+  yygotominor.yy322 = sqlite3ExprListAppend(pParse, yymsp[-1].minor.yy322, p);
 }
         break;
       case 126: /* selcollist ::= sclp nm DOT STAR */
@@ -99926,50 +101745,50 @@
   Expr *pRight = sqlite3PExpr(pParse, TK_ALL, 0, 0, &yymsp[0].minor.yy0);
   Expr *pLeft = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[-2].minor.yy0);
   Expr *pDot = sqlite3PExpr(pParse, TK_DOT, pLeft, pRight, 0);
-  yygotominor.yy14 = sqlite3ExprListAppend(pParse,yymsp[-3].minor.yy14, pDot);
+  yygotominor.yy322 = sqlite3ExprListAppend(pParse,yymsp[-3].minor.yy322, pDot);
 }
         break;
       case 129: /* as ::= */
 {yygotominor.yy0.n = 0;}
         break;
       case 130: /* from ::= */
-{yygotominor.yy65 = sqlite3DbMallocZero(pParse->db, sizeof(*yygotominor.yy65));}
+{yygotominor.yy259 = sqlite3DbMallocZero(pParse->db, sizeof(*yygotominor.yy259));}
         break;
       case 131: /* from ::= FROM seltablist */
 {
-  yygotominor.yy65 = yymsp[0].minor.yy65;
-  sqlite3SrcListShiftJoinType(yygotominor.yy65);
+  yygotominor.yy259 = yymsp[0].minor.yy259;
+  sqlite3SrcListShiftJoinType(yygotominor.yy259);
 }
         break;
       case 132: /* stl_prefix ::= seltablist joinop */
 {
-   yygotominor.yy65 = yymsp[-1].minor.yy65;
-   if( ALWAYS(yygotominor.yy65 && yygotominor.yy65->nSrc>0) ) yygotominor.yy65->a[yygotominor.yy65->nSrc-1].jointype = (u8)yymsp[0].minor.yy328;
+   yygotominor.yy259 = yymsp[-1].minor.yy259;
+   if( ALWAYS(yygotominor.yy259 && yygotominor.yy259->nSrc>0) ) yygotominor.yy259->a[yygotominor.yy259->nSrc-1].jointype = (u8)yymsp[0].minor.yy4;
 }
         break;
       case 133: /* stl_prefix ::= */
-{yygotominor.yy65 = 0;}
+{yygotominor.yy259 = 0;}
         break;
       case 134: /* seltablist ::= stl_prefix nm dbnm as indexed_opt on_opt using_opt */
 {
-  yygotominor.yy65 = sqlite3SrcListAppendFromTerm(pParse,yymsp[-6].minor.yy65,&yymsp[-5].minor.yy0,&yymsp[-4].minor.yy0,&yymsp[-3].minor.yy0,0,yymsp[-1].minor.yy132,yymsp[0].minor.yy408);
-  sqlite3SrcListIndexedBy(pParse, yygotominor.yy65, &yymsp[-2].minor.yy0);
+  yygotominor.yy259 = sqlite3SrcListAppendFromTerm(pParse,yymsp[-6].minor.yy259,&yymsp[-5].minor.yy0,&yymsp[-4].minor.yy0,&yymsp[-3].minor.yy0,0,yymsp[-1].minor.yy314,yymsp[0].minor.yy384);
+  sqlite3SrcListIndexedBy(pParse, yygotominor.yy259, &yymsp[-2].minor.yy0);
 }
         break;
       case 135: /* seltablist ::= stl_prefix LP select RP as on_opt using_opt */
 {
-    yygotominor.yy65 = sqlite3SrcListAppendFromTerm(pParse,yymsp[-6].minor.yy65,0,0,&yymsp[-2].minor.yy0,yymsp[-4].minor.yy3,yymsp[-1].minor.yy132,yymsp[0].minor.yy408);
+    yygotominor.yy259 = sqlite3SrcListAppendFromTerm(pParse,yymsp[-6].minor.yy259,0,0,&yymsp[-2].minor.yy0,yymsp[-4].minor.yy387,yymsp[-1].minor.yy314,yymsp[0].minor.yy384);
   }
         break;
       case 136: /* seltablist ::= stl_prefix LP seltablist RP as on_opt using_opt */
 {
-    if( yymsp[-6].minor.yy65==0 && yymsp[-2].minor.yy0.n==0 && yymsp[-1].minor.yy132==0 && yymsp[0].minor.yy408==0 ){
-      yygotominor.yy65 = yymsp[-4].minor.yy65;
+    if( yymsp[-6].minor.yy259==0 && yymsp[-2].minor.yy0.n==0 && yymsp[-1].minor.yy314==0 && yymsp[0].minor.yy384==0 ){
+      yygotominor.yy259 = yymsp[-4].minor.yy259;
     }else{
       Select *pSubquery;
-      sqlite3SrcListShiftJoinType(yymsp[-4].minor.yy65);
-      pSubquery = sqlite3SelectNew(pParse,0,yymsp[-4].minor.yy65,0,0,0,0,0,0,0);
-      yygotominor.yy65 = sqlite3SrcListAppendFromTerm(pParse,yymsp[-6].minor.yy65,0,0,&yymsp[-2].minor.yy0,pSubquery,yymsp[-1].minor.yy132,yymsp[0].minor.yy408);
+      sqlite3SrcListShiftJoinType(yymsp[-4].minor.yy259);
+      pSubquery = sqlite3SelectNew(pParse,0,yymsp[-4].minor.yy259,0,0,0,0,0,0,0);
+      yygotominor.yy259 = sqlite3SrcListAppendFromTerm(pParse,yymsp[-6].minor.yy259,0,0,&yymsp[-2].minor.yy0,pSubquery,yymsp[-1].minor.yy314,yymsp[0].minor.yy384);
     }
   }
         break;
@@ -99978,158 +101797,157 @@
 {yygotominor.yy0.z=0; yygotominor.yy0.n=0;}
         break;
       case 139: /* fullname ::= nm dbnm */
-{yygotominor.yy65 = sqlite3SrcListAppend(pParse->db,0,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy0);}
+{yygotominor.yy259 = sqlite3SrcListAppend(pParse->db,0,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy0);}
         break;
       case 140: /* joinop ::= COMMA|JOIN */
-{ yygotominor.yy328 = JT_INNER; }
+{ yygotominor.yy4 = JT_INNER; }
         break;
       case 141: /* joinop ::= JOIN_KW JOIN */
-{ yygotominor.yy328 = sqlite3JoinType(pParse,&yymsp[-1].minor.yy0,0,0); }
+{ yygotominor.yy4 = sqlite3JoinType(pParse,&yymsp[-1].minor.yy0,0,0); }
         break;
       case 142: /* joinop ::= JOIN_KW nm JOIN */
-{ yygotominor.yy328 = sqlite3JoinType(pParse,&yymsp[-2].minor.yy0,&yymsp[-1].minor.yy0,0); }
+{ yygotominor.yy4 = sqlite3JoinType(pParse,&yymsp[-2].minor.yy0,&yymsp[-1].minor.yy0,0); }
         break;
       case 143: /* joinop ::= JOIN_KW nm nm JOIN */
-{ yygotominor.yy328 = sqlite3JoinType(pParse,&yymsp[-3].minor.yy0,&yymsp[-2].minor.yy0,&yymsp[-1].minor.yy0); }
+{ yygotominor.yy4 = sqlite3JoinType(pParse,&yymsp[-3].minor.yy0,&yymsp[-2].minor.yy0,&yymsp[-1].minor.yy0); }
         break;
       case 144: /* on_opt ::= ON expr */
       case 155: /* sortitem ::= expr */ yytestcase(yyruleno==155);
       case 162: /* having_opt ::= HAVING expr */ yytestcase(yyruleno==162);
       case 169: /* where_opt ::= WHERE expr */ yytestcase(yyruleno==169);
-      case 236: /* case_else ::= ELSE expr */ yytestcase(yyruleno==236);
-      case 238: /* case_operand ::= expr */ yytestcase(yyruleno==238);
-{yygotominor.yy132 = yymsp[0].minor.yy346.pExpr;}
+      case 235: /* case_else ::= ELSE expr */ yytestcase(yyruleno==235);
+      case 237: /* case_operand ::= expr */ yytestcase(yyruleno==237);
+{yygotominor.yy314 = yymsp[0].minor.yy118.pExpr;}
         break;
       case 145: /* on_opt ::= */
       case 161: /* having_opt ::= */ yytestcase(yyruleno==161);
       case 168: /* where_opt ::= */ yytestcase(yyruleno==168);
-      case 237: /* case_else ::= */ yytestcase(yyruleno==237);
-      case 239: /* case_operand ::= */ yytestcase(yyruleno==239);
-{yygotominor.yy132 = 0;}
+      case 236: /* case_else ::= */ yytestcase(yyruleno==236);
+      case 238: /* case_operand ::= */ yytestcase(yyruleno==238);
+{yygotominor.yy314 = 0;}
         break;
       case 148: /* indexed_opt ::= NOT INDEXED */
 {yygotominor.yy0.z=0; yygotominor.yy0.n=1;}
         break;
       case 149: /* using_opt ::= USING LP inscollist RP */
       case 181: /* inscollist_opt ::= LP inscollist RP */ yytestcase(yyruleno==181);
-{yygotominor.yy408 = yymsp[-1].minor.yy408;}
+{yygotominor.yy384 = yymsp[-1].minor.yy384;}
         break;
       case 150: /* using_opt ::= */
       case 180: /* inscollist_opt ::= */ yytestcase(yyruleno==180);
-{yygotominor.yy408 = 0;}
+{yygotominor.yy384 = 0;}
         break;
       case 152: /* orderby_opt ::= ORDER BY sortlist */
       case 160: /* groupby_opt ::= GROUP BY nexprlist */ yytestcase(yyruleno==160);
-      case 240: /* exprlist ::= nexprlist */ yytestcase(yyruleno==240);
-{yygotominor.yy14 = yymsp[0].minor.yy14;}
+      case 239: /* exprlist ::= nexprlist */ yytestcase(yyruleno==239);
+{yygotominor.yy322 = yymsp[0].minor.yy322;}
         break;
       case 153: /* sortlist ::= sortlist COMMA sortitem sortorder */
 {
-  yygotominor.yy14 = sqlite3ExprListAppend(pParse,yymsp[-3].minor.yy14,yymsp[-1].minor.yy132);
-  if( yygotominor.yy14 ) yygotominor.yy14->a[yygotominor.yy14->nExpr-1].sortOrder = (u8)yymsp[0].minor.yy328;
+  yygotominor.yy322 = sqlite3ExprListAppend(pParse,yymsp[-3].minor.yy322,yymsp[-1].minor.yy314);
+  if( yygotominor.yy322 ) yygotominor.yy322->a[yygotominor.yy322->nExpr-1].sortOrder = (u8)yymsp[0].minor.yy4;
 }
         break;
       case 154: /* sortlist ::= sortitem sortorder */
 {
-  yygotominor.yy14 = sqlite3ExprListAppend(pParse,0,yymsp[-1].minor.yy132);
-  if( yygotominor.yy14 && ALWAYS(yygotominor.yy14->a) ) yygotominor.yy14->a[0].sortOrder = (u8)yymsp[0].minor.yy328;
+  yygotominor.yy322 = sqlite3ExprListAppend(pParse,0,yymsp[-1].minor.yy314);
+  if( yygotominor.yy322 && ALWAYS(yygotominor.yy322->a) ) yygotominor.yy322->a[0].sortOrder = (u8)yymsp[0].minor.yy4;
 }
         break;
       case 156: /* sortorder ::= ASC */
       case 158: /* sortorder ::= */ yytestcase(yyruleno==158);
-{yygotominor.yy328 = SQLITE_SO_ASC;}
+{yygotominor.yy4 = SQLITE_SO_ASC;}
         break;
       case 157: /* sortorder ::= DESC */
-{yygotominor.yy328 = SQLITE_SO_DESC;}
+{yygotominor.yy4 = SQLITE_SO_DESC;}
         break;
       case 163: /* limit_opt ::= */
-{yygotominor.yy476.pLimit = 0; yygotominor.yy476.pOffset = 0;}
+{yygotominor.yy292.pLimit = 0; yygotominor.yy292.pOffset = 0;}
         break;
       case 164: /* limit_opt ::= LIMIT expr */
-{yygotominor.yy476.pLimit = yymsp[0].minor.yy346.pExpr; yygotominor.yy476.pOffset = 0;}
+{yygotominor.yy292.pLimit = yymsp[0].minor.yy118.pExpr; yygotominor.yy292.pOffset = 0;}
         break;
       case 165: /* limit_opt ::= LIMIT expr OFFSET expr */
-{yygotominor.yy476.pLimit = yymsp[-2].minor.yy346.pExpr; yygotominor.yy476.pOffset = yymsp[0].minor.yy346.pExpr;}
+{yygotominor.yy292.pLimit = yymsp[-2].minor.yy118.pExpr; yygotominor.yy292.pOffset = yymsp[0].minor.yy118.pExpr;}
         break;
       case 166: /* limit_opt ::= LIMIT expr COMMA expr */
-{yygotominor.yy476.pOffset = yymsp[-2].minor.yy346.pExpr; yygotominor.yy476.pLimit = yymsp[0].minor.yy346.pExpr;}
+{yygotominor.yy292.pOffset = yymsp[-2].minor.yy118.pExpr; yygotominor.yy292.pLimit = yymsp[0].minor.yy118.pExpr;}
         break;
       case 167: /* cmd ::= DELETE FROM fullname indexed_opt where_opt */
 {
-  sqlite3SrcListIndexedBy(pParse, yymsp[-2].minor.yy65, &yymsp[-1].minor.yy0);
-  sqlite3DeleteFrom(pParse,yymsp[-2].minor.yy65,yymsp[0].minor.yy132);
+  sqlite3SrcListIndexedBy(pParse, yymsp[-2].minor.yy259, &yymsp[-1].minor.yy0);
+  sqlite3DeleteFrom(pParse,yymsp[-2].minor.yy259,yymsp[0].minor.yy314);
 }
         break;
       case 170: /* cmd ::= UPDATE orconf fullname indexed_opt SET setlist where_opt */
 {
-  sqlite3SrcListIndexedBy(pParse, yymsp[-4].minor.yy65, &yymsp[-3].minor.yy0);
-  sqlite3ExprListCheckLength(pParse,yymsp[-1].minor.yy14,"set list"); 
-  sqlite3Update(pParse,yymsp[-4].minor.yy65,yymsp[-1].minor.yy14,yymsp[0].minor.yy132,yymsp[-5].minor.yy186);
+  sqlite3SrcListIndexedBy(pParse, yymsp[-4].minor.yy259, &yymsp[-3].minor.yy0);
+  sqlite3ExprListCheckLength(pParse,yymsp[-1].minor.yy322,"set list"); 
+  sqlite3Update(pParse,yymsp[-4].minor.yy259,yymsp[-1].minor.yy322,yymsp[0].minor.yy314,yymsp[-5].minor.yy210);
 }
         break;
       case 171: /* setlist ::= setlist COMMA nm EQ expr */
 {
-  yygotominor.yy14 = sqlite3ExprListAppend(pParse, yymsp[-4].minor.yy14, yymsp[0].minor.yy346.pExpr);
-  sqlite3ExprListSetName(pParse, yygotominor.yy14, &yymsp[-2].minor.yy0, 1);
+  yygotominor.yy322 = sqlite3ExprListAppend(pParse, yymsp[-4].minor.yy322, yymsp[0].minor.yy118.pExpr);
+  sqlite3ExprListSetName(pParse, yygotominor.yy322, &yymsp[-2].minor.yy0, 1);
 }
         break;
       case 172: /* setlist ::= nm EQ expr */
 {
-  yygotominor.yy14 = sqlite3ExprListAppend(pParse, 0, yymsp[0].minor.yy346.pExpr);
-  sqlite3ExprListSetName(pParse, yygotominor.yy14, &yymsp[-2].minor.yy0, 1);
+  yygotominor.yy322 = sqlite3ExprListAppend(pParse, 0, yymsp[0].minor.yy118.pExpr);
+  sqlite3ExprListSetName(pParse, yygotominor.yy322, &yymsp[-2].minor.yy0, 1);
 }
         break;
       case 173: /* cmd ::= insert_cmd INTO fullname inscollist_opt VALUES LP itemlist RP */
-{sqlite3Insert(pParse, yymsp[-5].minor.yy65, yymsp[-1].minor.yy14, 0, yymsp[-4].minor.yy408, yymsp[-7].minor.yy186);}
+{sqlite3Insert(pParse, yymsp[-5].minor.yy259, yymsp[-1].minor.yy322, 0, yymsp[-4].minor.yy384, yymsp[-7].minor.yy210);}
         break;
       case 174: /* cmd ::= insert_cmd INTO fullname inscollist_opt select */
-{sqlite3Insert(pParse, yymsp[-2].minor.yy65, 0, yymsp[0].minor.yy3, yymsp[-1].minor.yy408, yymsp[-4].minor.yy186);}
+{sqlite3Insert(pParse, yymsp[-2].minor.yy259, 0, yymsp[0].minor.yy387, yymsp[-1].minor.yy384, yymsp[-4].minor.yy210);}
         break;
       case 175: /* cmd ::= insert_cmd INTO fullname inscollist_opt DEFAULT VALUES */
-{sqlite3Insert(pParse, yymsp[-3].minor.yy65, 0, 0, yymsp[-2].minor.yy408, yymsp[-5].minor.yy186);}
+{sqlite3Insert(pParse, yymsp[-3].minor.yy259, 0, 0, yymsp[-2].minor.yy384, yymsp[-5].minor.yy210);}
         break;
       case 176: /* insert_cmd ::= INSERT orconf */
-{yygotominor.yy186 = yymsp[0].minor.yy186;}
+{yygotominor.yy210 = yymsp[0].minor.yy210;}
         break;
       case 177: /* insert_cmd ::= REPLACE */
-{yygotominor.yy186 = OE_Replace;}
+{yygotominor.yy210 = OE_Replace;}
         break;
       case 178: /* itemlist ::= itemlist COMMA expr */
-      case 242: /* nexprlist ::= nexprlist COMMA expr */ yytestcase(yyruleno==242);
-{yygotominor.yy14 = sqlite3ExprListAppend(pParse,yymsp[-2].minor.yy14,yymsp[0].minor.yy346.pExpr);}
+      case 241: /* nexprlist ::= nexprlist COMMA expr */ yytestcase(yyruleno==241);
+{yygotominor.yy322 = sqlite3ExprListAppend(pParse,yymsp[-2].minor.yy322,yymsp[0].minor.yy118.pExpr);}
         break;
       case 179: /* itemlist ::= expr */
-      case 243: /* nexprlist ::= expr */ yytestcase(yyruleno==243);
-{yygotominor.yy14 = sqlite3ExprListAppend(pParse,0,yymsp[0].minor.yy346.pExpr);}
+      case 242: /* nexprlist ::= expr */ yytestcase(yyruleno==242);
+{yygotominor.yy322 = sqlite3ExprListAppend(pParse,0,yymsp[0].minor.yy118.pExpr);}
         break;
       case 182: /* inscollist ::= inscollist COMMA nm */
-{yygotominor.yy408 = sqlite3IdListAppend(pParse->db,yymsp[-2].minor.yy408,&yymsp[0].minor.yy0);}
+{yygotominor.yy384 = sqlite3IdListAppend(pParse->db,yymsp[-2].minor.yy384,&yymsp[0].minor.yy0);}
         break;
       case 183: /* inscollist ::= nm */
-{yygotominor.yy408 = sqlite3IdListAppend(pParse->db,0,&yymsp[0].minor.yy0);}
+{yygotominor.yy384 = sqlite3IdListAppend(pParse->db,0,&yymsp[0].minor.yy0);}
         break;
       case 184: /* expr ::= term */
-      case 212: /* escape ::= ESCAPE expr */ yytestcase(yyruleno==212);
-{yygotominor.yy346 = yymsp[0].minor.yy346;}
+{yygotominor.yy118 = yymsp[0].minor.yy118;}
         break;
       case 185: /* expr ::= LP expr RP */
-{yygotominor.yy346.pExpr = yymsp[-1].minor.yy346.pExpr; spanSet(&yygotominor.yy346,&yymsp[-2].minor.yy0,&yymsp[0].minor.yy0);}
+{yygotominor.yy118.pExpr = yymsp[-1].minor.yy118.pExpr; spanSet(&yygotominor.yy118,&yymsp[-2].minor.yy0,&yymsp[0].minor.yy0);}
         break;
       case 186: /* term ::= NULL */
       case 191: /* term ::= INTEGER|FLOAT|BLOB */ yytestcase(yyruleno==191);
       case 192: /* term ::= STRING */ yytestcase(yyruleno==192);
-{spanExpr(&yygotominor.yy346, pParse, yymsp[0].major, &yymsp[0].minor.yy0);}
+{spanExpr(&yygotominor.yy118, pParse, yymsp[0].major, &yymsp[0].minor.yy0);}
         break;
       case 187: /* expr ::= id */
       case 188: /* expr ::= JOIN_KW */ yytestcase(yyruleno==188);
-{spanExpr(&yygotominor.yy346, pParse, TK_ID, &yymsp[0].minor.yy0);}
+{spanExpr(&yygotominor.yy118, pParse, TK_ID, &yymsp[0].minor.yy0);}
         break;
       case 189: /* expr ::= nm DOT nm */
 {
   Expr *temp1 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[-2].minor.yy0);
   Expr *temp2 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[0].minor.yy0);
-  yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_DOT, temp1, temp2, 0);
-  spanSet(&yygotominor.yy346,&yymsp[-2].minor.yy0,&yymsp[0].minor.yy0);
+  yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_DOT, temp1, temp2, 0);
+  spanSet(&yygotominor.yy118,&yymsp[-2].minor.yy0,&yymsp[0].minor.yy0);
 }
         break;
       case 190: /* expr ::= nm DOT nm DOT nm */
@@ -100138,8 +101956,8 @@
   Expr *temp2 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[-2].minor.yy0);
   Expr *temp3 = sqlite3PExpr(pParse, TK_ID, 0, 0, &yymsp[0].minor.yy0);
   Expr *temp4 = sqlite3PExpr(pParse, TK_DOT, temp2, temp3, 0);
-  yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_DOT, temp1, temp4, 0);
-  spanSet(&yygotominor.yy346,&yymsp[-4].minor.yy0,&yymsp[0].minor.yy0);
+  yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_DOT, temp1, temp4, 0);
+  spanSet(&yygotominor.yy118,&yymsp[-4].minor.yy0,&yymsp[0].minor.yy0);
 }
         break;
       case 193: /* expr ::= REGISTER */
@@ -100149,61 +101967,61 @@
   ** in the virtual machine.  #N is the N-th register. */
   if( pParse->nested==0 ){
     sqlite3ErrorMsg(pParse, "near \"%T\": syntax error", &yymsp[0].minor.yy0);
-    yygotominor.yy346.pExpr = 0;
+    yygotominor.yy118.pExpr = 0;
   }else{
-    yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_REGISTER, 0, 0, &yymsp[0].minor.yy0);
-    if( yygotominor.yy346.pExpr ) sqlite3GetInt32(&yymsp[0].minor.yy0.z[1], &yygotominor.yy346.pExpr->iTable);
+    yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_REGISTER, 0, 0, &yymsp[0].minor.yy0);
+    if( yygotominor.yy118.pExpr ) sqlite3GetInt32(&yymsp[0].minor.yy0.z[1], &yygotominor.yy118.pExpr->iTable);
   }
-  spanSet(&yygotominor.yy346, &yymsp[0].minor.yy0, &yymsp[0].minor.yy0);
+  spanSet(&yygotominor.yy118, &yymsp[0].minor.yy0, &yymsp[0].minor.yy0);
 }
         break;
       case 194: /* expr ::= VARIABLE */
 {
-  spanExpr(&yygotominor.yy346, pParse, TK_VARIABLE, &yymsp[0].minor.yy0);
-  sqlite3ExprAssignVarNumber(pParse, yygotominor.yy346.pExpr);
-  spanSet(&yygotominor.yy346, &yymsp[0].minor.yy0, &yymsp[0].minor.yy0);
+  spanExpr(&yygotominor.yy118, pParse, TK_VARIABLE, &yymsp[0].minor.yy0);
+  sqlite3ExprAssignVarNumber(pParse, yygotominor.yy118.pExpr);
+  spanSet(&yygotominor.yy118, &yymsp[0].minor.yy0, &yymsp[0].minor.yy0);
 }
         break;
       case 195: /* expr ::= expr COLLATE ids */
 {
-  yygotominor.yy346.pExpr = sqlite3ExprSetColl(pParse, yymsp[-2].minor.yy346.pExpr, &yymsp[0].minor.yy0);
-  yygotominor.yy346.zStart = yymsp[-2].minor.yy346.zStart;
-  yygotominor.yy346.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
+  yygotominor.yy118.pExpr = sqlite3ExprSetCollByToken(pParse, yymsp[-2].minor.yy118.pExpr, &yymsp[0].minor.yy0);
+  yygotominor.yy118.zStart = yymsp[-2].minor.yy118.zStart;
+  yygotominor.yy118.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
 }
         break;
       case 196: /* expr ::= CAST LP expr AS typetoken RP */
 {
-  yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_CAST, yymsp[-3].minor.yy346.pExpr, 0, &yymsp[-1].minor.yy0);
-  spanSet(&yygotominor.yy346,&yymsp[-5].minor.yy0,&yymsp[0].minor.yy0);
+  yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_CAST, yymsp[-3].minor.yy118.pExpr, 0, &yymsp[-1].minor.yy0);
+  spanSet(&yygotominor.yy118,&yymsp[-5].minor.yy0,&yymsp[0].minor.yy0);
 }
         break;
       case 197: /* expr ::= ID LP distinct exprlist RP */
 {
-  if( yymsp[-1].minor.yy14 && yymsp[-1].minor.yy14->nExpr>pParse->db->aLimit[SQLITE_LIMIT_FUNCTION_ARG] ){
+  if( yymsp[-1].minor.yy322 && yymsp[-1].minor.yy322->nExpr>pParse->db->aLimit[SQLITE_LIMIT_FUNCTION_ARG] ){
     sqlite3ErrorMsg(pParse, "too many arguments on function %T", &yymsp[-4].minor.yy0);
   }
-  yygotominor.yy346.pExpr = sqlite3ExprFunction(pParse, yymsp[-1].minor.yy14, &yymsp[-4].minor.yy0);
-  spanSet(&yygotominor.yy346,&yymsp[-4].minor.yy0,&yymsp[0].minor.yy0);
-  if( yymsp[-2].minor.yy328 && yygotominor.yy346.pExpr ){
-    yygotominor.yy346.pExpr->flags |= EP_Distinct;
+  yygotominor.yy118.pExpr = sqlite3ExprFunction(pParse, yymsp[-1].minor.yy322, &yymsp[-4].minor.yy0);
+  spanSet(&yygotominor.yy118,&yymsp[-4].minor.yy0,&yymsp[0].minor.yy0);
+  if( yymsp[-2].minor.yy4 && yygotominor.yy118.pExpr ){
+    yygotominor.yy118.pExpr->flags |= EP_Distinct;
   }
 }
         break;
       case 198: /* expr ::= ID LP STAR RP */
 {
-  yygotominor.yy346.pExpr = sqlite3ExprFunction(pParse, 0, &yymsp[-3].minor.yy0);
-  spanSet(&yygotominor.yy346,&yymsp[-3].minor.yy0,&yymsp[0].minor.yy0);
+  yygotominor.yy118.pExpr = sqlite3ExprFunction(pParse, 0, &yymsp[-3].minor.yy0);
+  spanSet(&yygotominor.yy118,&yymsp[-3].minor.yy0,&yymsp[0].minor.yy0);
 }
         break;
       case 199: /* term ::= CTIME_KW */
 {
   /* The CURRENT_TIME, CURRENT_DATE, and CURRENT_TIMESTAMP values are
   ** treated as functions that return constants */
-  yygotominor.yy346.pExpr = sqlite3ExprFunction(pParse, 0,&yymsp[0].minor.yy0);
-  if( yygotominor.yy346.pExpr ){
-    yygotominor.yy346.pExpr->op = TK_CONST_FUNC;  
+  yygotominor.yy118.pExpr = sqlite3ExprFunction(pParse, 0,&yymsp[0].minor.yy0);
+  if( yygotominor.yy118.pExpr ){
+    yygotominor.yy118.pExpr->op = TK_CONST_FUNC;  
   }
-  spanSet(&yygotominor.yy346, &yymsp[0].minor.yy0, &yymsp[0].minor.yy0);
+  spanSet(&yygotominor.yy118, &yymsp[0].minor.yy0, &yymsp[0].minor.yy0);
 }
         break;
       case 200: /* expr ::= expr AND expr */
@@ -100214,295 +102032,315 @@
       case 205: /* expr ::= expr PLUS|MINUS expr */ yytestcase(yyruleno==205);
       case 206: /* expr ::= expr STAR|SLASH|REM expr */ yytestcase(yyruleno==206);
       case 207: /* expr ::= expr CONCAT expr */ yytestcase(yyruleno==207);
-{spanBinaryExpr(&yygotominor.yy346,pParse,yymsp[-1].major,&yymsp[-2].minor.yy346,&yymsp[0].minor.yy346);}
+{spanBinaryExpr(&yygotominor.yy118,pParse,yymsp[-1].major,&yymsp[-2].minor.yy118,&yymsp[0].minor.yy118);}
         break;
       case 208: /* likeop ::= LIKE_KW */
       case 210: /* likeop ::= MATCH */ yytestcase(yyruleno==210);
-{yygotominor.yy96.eOperator = yymsp[0].minor.yy0; yygotominor.yy96.not = 0;}
+{yygotominor.yy342.eOperator = yymsp[0].minor.yy0; yygotominor.yy342.not = 0;}
         break;
       case 209: /* likeop ::= NOT LIKE_KW */
       case 211: /* likeop ::= NOT MATCH */ yytestcase(yyruleno==211);
-{yygotominor.yy96.eOperator = yymsp[0].minor.yy0; yygotominor.yy96.not = 1;}
+{yygotominor.yy342.eOperator = yymsp[0].minor.yy0; yygotominor.yy342.not = 1;}
         break;
-      case 213: /* escape ::= */
-{memset(&yygotominor.yy346,0,sizeof(yygotominor.yy346));}
-        break;
-      case 214: /* expr ::= expr likeop expr escape */
+      case 212: /* expr ::= expr likeop expr */
 {
   ExprList *pList;
-  pList = sqlite3ExprListAppend(pParse,0, yymsp[-1].minor.yy346.pExpr);
-  pList = sqlite3ExprListAppend(pParse,pList, yymsp[-3].minor.yy346.pExpr);
-  if( yymsp[0].minor.yy346.pExpr ){
-    pList = sqlite3ExprListAppend(pParse,pList, yymsp[0].minor.yy346.pExpr);
-  }
-  yygotominor.yy346.pExpr = sqlite3ExprFunction(pParse, pList, &yymsp[-2].minor.yy96.eOperator);
-  if( yymsp[-2].minor.yy96.not ) yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy346.pExpr, 0, 0);
-  yygotominor.yy346.zStart = yymsp[-3].minor.yy346.zStart;
-  yygotominor.yy346.zEnd = yymsp[-1].minor.yy346.zEnd;
-  if( yygotominor.yy346.pExpr ) yygotominor.yy346.pExpr->flags |= EP_InfixFunc;
+  pList = sqlite3ExprListAppend(pParse,0, yymsp[0].minor.yy118.pExpr);
+  pList = sqlite3ExprListAppend(pParse,pList, yymsp[-2].minor.yy118.pExpr);
+  yygotominor.yy118.pExpr = sqlite3ExprFunction(pParse, pList, &yymsp[-1].minor.yy342.eOperator);
+  if( yymsp[-1].minor.yy342.not ) yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy118.pExpr, 0, 0);
+  yygotominor.yy118.zStart = yymsp[-2].minor.yy118.zStart;
+  yygotominor.yy118.zEnd = yymsp[0].minor.yy118.zEnd;
+  if( yygotominor.yy118.pExpr ) yygotominor.yy118.pExpr->flags |= EP_InfixFunc;
 }
         break;
-      case 215: /* expr ::= expr ISNULL|NOTNULL */
-{spanUnaryPostfix(&yygotominor.yy346,pParse,yymsp[0].major,&yymsp[-1].minor.yy346,&yymsp[0].minor.yy0);}
-        break;
-      case 216: /* expr ::= expr NOT NULL */
-{spanUnaryPostfix(&yygotominor.yy346,pParse,TK_NOTNULL,&yymsp[-2].minor.yy346,&yymsp[0].minor.yy0);}
-        break;
-      case 217: /* expr ::= expr IS expr */
+      case 213: /* expr ::= expr likeop expr ESCAPE expr */
 {
-  spanBinaryExpr(&yygotominor.yy346,pParse,TK_IS,&yymsp[-2].minor.yy346,&yymsp[0].minor.yy346);
-  binaryToUnaryIfNull(pParse, yymsp[0].minor.yy346.pExpr, yygotominor.yy346.pExpr, TK_ISNULL);
+  ExprList *pList;
+  pList = sqlite3ExprListAppend(pParse,0, yymsp[-2].minor.yy118.pExpr);
+  pList = sqlite3ExprListAppend(pParse,pList, yymsp[-4].minor.yy118.pExpr);
+  pList = sqlite3ExprListAppend(pParse,pList, yymsp[0].minor.yy118.pExpr);
+  yygotominor.yy118.pExpr = sqlite3ExprFunction(pParse, pList, &yymsp[-3].minor.yy342.eOperator);
+  if( yymsp[-3].minor.yy342.not ) yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy118.pExpr, 0, 0);
+  yygotominor.yy118.zStart = yymsp[-4].minor.yy118.zStart;
+  yygotominor.yy118.zEnd = yymsp[0].minor.yy118.zEnd;
+  if( yygotominor.yy118.pExpr ) yygotominor.yy118.pExpr->flags |= EP_InfixFunc;
 }
         break;
-      case 218: /* expr ::= expr IS NOT expr */
+      case 214: /* expr ::= expr ISNULL|NOTNULL */
+{spanUnaryPostfix(&yygotominor.yy118,pParse,yymsp[0].major,&yymsp[-1].minor.yy118,&yymsp[0].minor.yy0);}
+        break;
+      case 215: /* expr ::= expr NOT NULL */
+{spanUnaryPostfix(&yygotominor.yy118,pParse,TK_NOTNULL,&yymsp[-2].minor.yy118,&yymsp[0].minor.yy0);}
+        break;
+      case 216: /* expr ::= expr IS expr */
 {
-  spanBinaryExpr(&yygotominor.yy346,pParse,TK_ISNOT,&yymsp[-3].minor.yy346,&yymsp[0].minor.yy346);
-  binaryToUnaryIfNull(pParse, yymsp[0].minor.yy346.pExpr, yygotominor.yy346.pExpr, TK_NOTNULL);
+  spanBinaryExpr(&yygotominor.yy118,pParse,TK_IS,&yymsp[-2].minor.yy118,&yymsp[0].minor.yy118);
+  binaryToUnaryIfNull(pParse, yymsp[0].minor.yy118.pExpr, yygotominor.yy118.pExpr, TK_ISNULL);
 }
         break;
-      case 219: /* expr ::= NOT expr */
-      case 220: /* expr ::= BITNOT expr */ yytestcase(yyruleno==220);
-{spanUnaryPrefix(&yygotominor.yy346,pParse,yymsp[-1].major,&yymsp[0].minor.yy346,&yymsp[-1].minor.yy0);}
-        break;
-      case 221: /* expr ::= MINUS expr */
-{spanUnaryPrefix(&yygotominor.yy346,pParse,TK_UMINUS,&yymsp[0].minor.yy346,&yymsp[-1].minor.yy0);}
-        break;
-      case 222: /* expr ::= PLUS expr */
-{spanUnaryPrefix(&yygotominor.yy346,pParse,TK_UPLUS,&yymsp[0].minor.yy346,&yymsp[-1].minor.yy0);}
-        break;
-      case 225: /* expr ::= expr between_op expr AND expr */
+      case 217: /* expr ::= expr IS NOT expr */
 {
-  ExprList *pList = sqlite3ExprListAppend(pParse,0, yymsp[-2].minor.yy346.pExpr);
-  pList = sqlite3ExprListAppend(pParse,pList, yymsp[0].minor.yy346.pExpr);
-  yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_BETWEEN, yymsp[-4].minor.yy346.pExpr, 0, 0);
-  if( yygotominor.yy346.pExpr ){
-    yygotominor.yy346.pExpr->x.pList = pList;
+  spanBinaryExpr(&yygotominor.yy118,pParse,TK_ISNOT,&yymsp[-3].minor.yy118,&yymsp[0].minor.yy118);
+  binaryToUnaryIfNull(pParse, yymsp[0].minor.yy118.pExpr, yygotominor.yy118.pExpr, TK_NOTNULL);
+}
+        break;
+      case 218: /* expr ::= NOT expr */
+      case 219: /* expr ::= BITNOT expr */ yytestcase(yyruleno==219);
+{spanUnaryPrefix(&yygotominor.yy118,pParse,yymsp[-1].major,&yymsp[0].minor.yy118,&yymsp[-1].minor.yy0);}
+        break;
+      case 220: /* expr ::= MINUS expr */
+{spanUnaryPrefix(&yygotominor.yy118,pParse,TK_UMINUS,&yymsp[0].minor.yy118,&yymsp[-1].minor.yy0);}
+        break;
+      case 221: /* expr ::= PLUS expr */
+{spanUnaryPrefix(&yygotominor.yy118,pParse,TK_UPLUS,&yymsp[0].minor.yy118,&yymsp[-1].minor.yy0);}
+        break;
+      case 224: /* expr ::= expr between_op expr AND expr */
+{
+  ExprList *pList = sqlite3ExprListAppend(pParse,0, yymsp[-2].minor.yy118.pExpr);
+  pList = sqlite3ExprListAppend(pParse,pList, yymsp[0].minor.yy118.pExpr);
+  yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_BETWEEN, yymsp[-4].minor.yy118.pExpr, 0, 0);
+  if( yygotominor.yy118.pExpr ){
+    yygotominor.yy118.pExpr->x.pList = pList;
   }else{
     sqlite3ExprListDelete(pParse->db, pList);
   } 
-  if( yymsp[-3].minor.yy328 ) yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy346.pExpr, 0, 0);
-  yygotominor.yy346.zStart = yymsp[-4].minor.yy346.zStart;
-  yygotominor.yy346.zEnd = yymsp[0].minor.yy346.zEnd;
+  if( yymsp[-3].minor.yy4 ) yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy118.pExpr, 0, 0);
+  yygotominor.yy118.zStart = yymsp[-4].minor.yy118.zStart;
+  yygotominor.yy118.zEnd = yymsp[0].minor.yy118.zEnd;
 }
         break;
-      case 228: /* expr ::= expr in_op LP exprlist RP */
+      case 227: /* expr ::= expr in_op LP exprlist RP */
 {
-    yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_IN, yymsp[-4].minor.yy346.pExpr, 0, 0);
-    if( yygotominor.yy346.pExpr ){
-      yygotominor.yy346.pExpr->x.pList = yymsp[-1].minor.yy14;
-      sqlite3ExprSetHeight(pParse, yygotominor.yy346.pExpr);
+    if( yymsp[-1].minor.yy322==0 ){
+      /* Expressions of the form
+      **
+      **      expr1 IN ()
+      **      expr1 NOT IN ()
+      **
+      ** simplify to constants 0 (false) and 1 (true), respectively,
+      ** regardless of the value of expr1.
+      */
+      yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_INTEGER, 0, 0, &sqlite3IntTokens[yymsp[-3].minor.yy4]);
+      sqlite3ExprDelete(pParse->db, yymsp[-4].minor.yy118.pExpr);
     }else{
-      sqlite3ExprListDelete(pParse->db, yymsp[-1].minor.yy14);
+      yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_IN, yymsp[-4].minor.yy118.pExpr, 0, 0);
+      if( yygotominor.yy118.pExpr ){
+        yygotominor.yy118.pExpr->x.pList = yymsp[-1].minor.yy322;
+        sqlite3ExprSetHeight(pParse, yygotominor.yy118.pExpr);
+      }else{
+        sqlite3ExprListDelete(pParse->db, yymsp[-1].minor.yy322);
+      }
+      if( yymsp[-3].minor.yy4 ) yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy118.pExpr, 0, 0);
     }
-    if( yymsp[-3].minor.yy328 ) yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy346.pExpr, 0, 0);
-    yygotominor.yy346.zStart = yymsp[-4].minor.yy346.zStart;
-    yygotominor.yy346.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
+    yygotominor.yy118.zStart = yymsp[-4].minor.yy118.zStart;
+    yygotominor.yy118.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
   }
         break;
-      case 229: /* expr ::= LP select RP */
+      case 228: /* expr ::= LP select RP */
 {
-    yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_SELECT, 0, 0, 0);
-    if( yygotominor.yy346.pExpr ){
-      yygotominor.yy346.pExpr->x.pSelect = yymsp[-1].minor.yy3;
-      ExprSetProperty(yygotominor.yy346.pExpr, EP_xIsSelect);
-      sqlite3ExprSetHeight(pParse, yygotominor.yy346.pExpr);
+    yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_SELECT, 0, 0, 0);
+    if( yygotominor.yy118.pExpr ){
+      yygotominor.yy118.pExpr->x.pSelect = yymsp[-1].minor.yy387;
+      ExprSetProperty(yygotominor.yy118.pExpr, EP_xIsSelect);
+      sqlite3ExprSetHeight(pParse, yygotominor.yy118.pExpr);
     }else{
-      sqlite3SelectDelete(pParse->db, yymsp[-1].minor.yy3);
+      sqlite3SelectDelete(pParse->db, yymsp[-1].minor.yy387);
     }
-    yygotominor.yy346.zStart = yymsp[-2].minor.yy0.z;
-    yygotominor.yy346.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
+    yygotominor.yy118.zStart = yymsp[-2].minor.yy0.z;
+    yygotominor.yy118.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
   }
         break;
-      case 230: /* expr ::= expr in_op LP select RP */
+      case 229: /* expr ::= expr in_op LP select RP */
 {
-    yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_IN, yymsp[-4].minor.yy346.pExpr, 0, 0);
-    if( yygotominor.yy346.pExpr ){
-      yygotominor.yy346.pExpr->x.pSelect = yymsp[-1].minor.yy3;
-      ExprSetProperty(yygotominor.yy346.pExpr, EP_xIsSelect);
-      sqlite3ExprSetHeight(pParse, yygotominor.yy346.pExpr);
+    yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_IN, yymsp[-4].minor.yy118.pExpr, 0, 0);
+    if( yygotominor.yy118.pExpr ){
+      yygotominor.yy118.pExpr->x.pSelect = yymsp[-1].minor.yy387;
+      ExprSetProperty(yygotominor.yy118.pExpr, EP_xIsSelect);
+      sqlite3ExprSetHeight(pParse, yygotominor.yy118.pExpr);
     }else{
-      sqlite3SelectDelete(pParse->db, yymsp[-1].minor.yy3);
+      sqlite3SelectDelete(pParse->db, yymsp[-1].minor.yy387);
     }
-    if( yymsp[-3].minor.yy328 ) yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy346.pExpr, 0, 0);
-    yygotominor.yy346.zStart = yymsp[-4].minor.yy346.zStart;
-    yygotominor.yy346.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
+    if( yymsp[-3].minor.yy4 ) yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy118.pExpr, 0, 0);
+    yygotominor.yy118.zStart = yymsp[-4].minor.yy118.zStart;
+    yygotominor.yy118.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
   }
         break;
-      case 231: /* expr ::= expr in_op nm dbnm */
+      case 230: /* expr ::= expr in_op nm dbnm */
 {
     SrcList *pSrc = sqlite3SrcListAppend(pParse->db, 0,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy0);
-    yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_IN, yymsp[-3].minor.yy346.pExpr, 0, 0);
-    if( yygotominor.yy346.pExpr ){
-      yygotominor.yy346.pExpr->x.pSelect = sqlite3SelectNew(pParse, 0,pSrc,0,0,0,0,0,0,0);
-      ExprSetProperty(yygotominor.yy346.pExpr, EP_xIsSelect);
-      sqlite3ExprSetHeight(pParse, yygotominor.yy346.pExpr);
+    yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_IN, yymsp[-3].minor.yy118.pExpr, 0, 0);
+    if( yygotominor.yy118.pExpr ){
+      yygotominor.yy118.pExpr->x.pSelect = sqlite3SelectNew(pParse, 0,pSrc,0,0,0,0,0,0,0);
+      ExprSetProperty(yygotominor.yy118.pExpr, EP_xIsSelect);
+      sqlite3ExprSetHeight(pParse, yygotominor.yy118.pExpr);
     }else{
       sqlite3SrcListDelete(pParse->db, pSrc);
     }
-    if( yymsp[-2].minor.yy328 ) yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy346.pExpr, 0, 0);
-    yygotominor.yy346.zStart = yymsp[-3].minor.yy346.zStart;
-    yygotominor.yy346.zEnd = yymsp[0].minor.yy0.z ? &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n] : &yymsp[-1].minor.yy0.z[yymsp[-1].minor.yy0.n];
+    if( yymsp[-2].minor.yy4 ) yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_NOT, yygotominor.yy118.pExpr, 0, 0);
+    yygotominor.yy118.zStart = yymsp[-3].minor.yy118.zStart;
+    yygotominor.yy118.zEnd = yymsp[0].minor.yy0.z ? &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n] : &yymsp[-1].minor.yy0.z[yymsp[-1].minor.yy0.n];
   }
         break;
-      case 232: /* expr ::= EXISTS LP select RP */
+      case 231: /* expr ::= EXISTS LP select RP */
 {
-    Expr *p = yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_EXISTS, 0, 0, 0);
+    Expr *p = yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_EXISTS, 0, 0, 0);
     if( p ){
-      p->x.pSelect = yymsp[-1].minor.yy3;
+      p->x.pSelect = yymsp[-1].minor.yy387;
       ExprSetProperty(p, EP_xIsSelect);
       sqlite3ExprSetHeight(pParse, p);
     }else{
-      sqlite3SelectDelete(pParse->db, yymsp[-1].minor.yy3);
+      sqlite3SelectDelete(pParse->db, yymsp[-1].minor.yy387);
     }
-    yygotominor.yy346.zStart = yymsp[-3].minor.yy0.z;
-    yygotominor.yy346.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
+    yygotominor.yy118.zStart = yymsp[-3].minor.yy0.z;
+    yygotominor.yy118.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
   }
         break;
-      case 233: /* expr ::= CASE case_operand case_exprlist case_else END */
+      case 232: /* expr ::= CASE case_operand case_exprlist case_else END */
 {
-  yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_CASE, yymsp[-3].minor.yy132, yymsp[-1].minor.yy132, 0);
-  if( yygotominor.yy346.pExpr ){
-    yygotominor.yy346.pExpr->x.pList = yymsp[-2].minor.yy14;
-    sqlite3ExprSetHeight(pParse, yygotominor.yy346.pExpr);
+  yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_CASE, yymsp[-3].minor.yy314, yymsp[-1].minor.yy314, 0);
+  if( yygotominor.yy118.pExpr ){
+    yygotominor.yy118.pExpr->x.pList = yymsp[-2].minor.yy322;
+    sqlite3ExprSetHeight(pParse, yygotominor.yy118.pExpr);
   }else{
-    sqlite3ExprListDelete(pParse->db, yymsp[-2].minor.yy14);
+    sqlite3ExprListDelete(pParse->db, yymsp[-2].minor.yy322);
   }
-  yygotominor.yy346.zStart = yymsp[-4].minor.yy0.z;
-  yygotominor.yy346.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
+  yygotominor.yy118.zStart = yymsp[-4].minor.yy0.z;
+  yygotominor.yy118.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
 }
         break;
-      case 234: /* case_exprlist ::= case_exprlist WHEN expr THEN expr */
+      case 233: /* case_exprlist ::= case_exprlist WHEN expr THEN expr */
 {
-  yygotominor.yy14 = sqlite3ExprListAppend(pParse,yymsp[-4].minor.yy14, yymsp[-2].minor.yy346.pExpr);
-  yygotominor.yy14 = sqlite3ExprListAppend(pParse,yygotominor.yy14, yymsp[0].minor.yy346.pExpr);
+  yygotominor.yy322 = sqlite3ExprListAppend(pParse,yymsp[-4].minor.yy322, yymsp[-2].minor.yy118.pExpr);
+  yygotominor.yy322 = sqlite3ExprListAppend(pParse,yygotominor.yy322, yymsp[0].minor.yy118.pExpr);
 }
         break;
-      case 235: /* case_exprlist ::= WHEN expr THEN expr */
+      case 234: /* case_exprlist ::= WHEN expr THEN expr */
 {
-  yygotominor.yy14 = sqlite3ExprListAppend(pParse,0, yymsp[-2].minor.yy346.pExpr);
-  yygotominor.yy14 = sqlite3ExprListAppend(pParse,yygotominor.yy14, yymsp[0].minor.yy346.pExpr);
+  yygotominor.yy322 = sqlite3ExprListAppend(pParse,0, yymsp[-2].minor.yy118.pExpr);
+  yygotominor.yy322 = sqlite3ExprListAppend(pParse,yygotominor.yy322, yymsp[0].minor.yy118.pExpr);
 }
         break;
-      case 244: /* cmd ::= createkw uniqueflag INDEX ifnotexists nm dbnm ON nm LP idxlist RP */
+      case 243: /* cmd ::= createkw uniqueflag INDEX ifnotexists nm dbnm ON nm LP idxlist RP */
 {
   sqlite3CreateIndex(pParse, &yymsp[-6].minor.yy0, &yymsp[-5].minor.yy0, 
-                     sqlite3SrcListAppend(pParse->db,0,&yymsp[-3].minor.yy0,0), yymsp[-1].minor.yy14, yymsp[-9].minor.yy328,
-                      &yymsp[-10].minor.yy0, &yymsp[0].minor.yy0, SQLITE_SO_ASC, yymsp[-7].minor.yy328);
+                     sqlite3SrcListAppend(pParse->db,0,&yymsp[-3].minor.yy0,0), yymsp[-1].minor.yy322, yymsp[-9].minor.yy4,
+                      &yymsp[-10].minor.yy0, &yymsp[0].minor.yy0, SQLITE_SO_ASC, yymsp[-7].minor.yy4);
 }
         break;
-      case 245: /* uniqueflag ::= UNIQUE */
-      case 299: /* raisetype ::= ABORT */ yytestcase(yyruleno==299);
-{yygotominor.yy328 = OE_Abort;}
+      case 244: /* uniqueflag ::= UNIQUE */
+      case 298: /* raisetype ::= ABORT */ yytestcase(yyruleno==298);
+{yygotominor.yy4 = OE_Abort;}
         break;
-      case 246: /* uniqueflag ::= */
-{yygotominor.yy328 = OE_None;}
+      case 245: /* uniqueflag ::= */
+{yygotominor.yy4 = OE_None;}
         break;
-      case 249: /* idxlist ::= idxlist COMMA nm collate sortorder */
+      case 248: /* idxlist ::= idxlist COMMA nm collate sortorder */
 {
   Expr *p = 0;
   if( yymsp[-1].minor.yy0.n>0 ){
     p = sqlite3Expr(pParse->db, TK_COLUMN, 0);
-    sqlite3ExprSetColl(pParse, p, &yymsp[-1].minor.yy0);
+    sqlite3ExprSetCollByToken(pParse, p, &yymsp[-1].minor.yy0);
   }
-  yygotominor.yy14 = sqlite3ExprListAppend(pParse,yymsp[-4].minor.yy14, p);
-  sqlite3ExprListSetName(pParse,yygotominor.yy14,&yymsp[-2].minor.yy0,1);
-  sqlite3ExprListCheckLength(pParse, yygotominor.yy14, "index");
-  if( yygotominor.yy14 ) yygotominor.yy14->a[yygotominor.yy14->nExpr-1].sortOrder = (u8)yymsp[0].minor.yy328;
+  yygotominor.yy322 = sqlite3ExprListAppend(pParse,yymsp[-4].minor.yy322, p);
+  sqlite3ExprListSetName(pParse,yygotominor.yy322,&yymsp[-2].minor.yy0,1);
+  sqlite3ExprListCheckLength(pParse, yygotominor.yy322, "index");
+  if( yygotominor.yy322 ) yygotominor.yy322->a[yygotominor.yy322->nExpr-1].sortOrder = (u8)yymsp[0].minor.yy4;
 }
         break;
-      case 250: /* idxlist ::= nm collate sortorder */
+      case 249: /* idxlist ::= nm collate sortorder */
 {
   Expr *p = 0;
   if( yymsp[-1].minor.yy0.n>0 ){
     p = sqlite3PExpr(pParse, TK_COLUMN, 0, 0, 0);
-    sqlite3ExprSetColl(pParse, p, &yymsp[-1].minor.yy0);
+    sqlite3ExprSetCollByToken(pParse, p, &yymsp[-1].minor.yy0);
   }
-  yygotominor.yy14 = sqlite3ExprListAppend(pParse,0, p);
-  sqlite3ExprListSetName(pParse, yygotominor.yy14, &yymsp[-2].minor.yy0, 1);
-  sqlite3ExprListCheckLength(pParse, yygotominor.yy14, "index");
-  if( yygotominor.yy14 ) yygotominor.yy14->a[yygotominor.yy14->nExpr-1].sortOrder = (u8)yymsp[0].minor.yy328;
+  yygotominor.yy322 = sqlite3ExprListAppend(pParse,0, p);
+  sqlite3ExprListSetName(pParse, yygotominor.yy322, &yymsp[-2].minor.yy0, 1);
+  sqlite3ExprListCheckLength(pParse, yygotominor.yy322, "index");
+  if( yygotominor.yy322 ) yygotominor.yy322->a[yygotominor.yy322->nExpr-1].sortOrder = (u8)yymsp[0].minor.yy4;
 }
         break;
-      case 251: /* collate ::= */
+      case 250: /* collate ::= */
 {yygotominor.yy0.z = 0; yygotominor.yy0.n = 0;}
         break;
-      case 253: /* cmd ::= DROP INDEX ifexists fullname */
-{sqlite3DropIndex(pParse, yymsp[0].minor.yy65, yymsp[-1].minor.yy328);}
+      case 252: /* cmd ::= DROP INDEX ifexists fullname */
+{sqlite3DropIndex(pParse, yymsp[0].minor.yy259, yymsp[-1].minor.yy4);}
         break;
-      case 254: /* cmd ::= VACUUM */
-      case 255: /* cmd ::= VACUUM nm */ yytestcase(yyruleno==255);
+      case 253: /* cmd ::= VACUUM */
+      case 254: /* cmd ::= VACUUM nm */ yytestcase(yyruleno==254);
 {sqlite3Vacuum(pParse);}
         break;
-      case 256: /* cmd ::= PRAGMA nm dbnm */
+      case 255: /* cmd ::= PRAGMA nm dbnm */
 {sqlite3Pragma(pParse,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy0,0,0);}
         break;
-      case 257: /* cmd ::= PRAGMA nm dbnm EQ nmnum */
+      case 256: /* cmd ::= PRAGMA nm dbnm EQ nmnum */
 {sqlite3Pragma(pParse,&yymsp[-3].minor.yy0,&yymsp[-2].minor.yy0,&yymsp[0].minor.yy0,0);}
         break;
-      case 258: /* cmd ::= PRAGMA nm dbnm LP nmnum RP */
+      case 257: /* cmd ::= PRAGMA nm dbnm LP nmnum RP */
 {sqlite3Pragma(pParse,&yymsp[-4].minor.yy0,&yymsp[-3].minor.yy0,&yymsp[-1].minor.yy0,0);}
         break;
-      case 259: /* cmd ::= PRAGMA nm dbnm EQ minus_num */
+      case 258: /* cmd ::= PRAGMA nm dbnm EQ minus_num */
 {sqlite3Pragma(pParse,&yymsp[-3].minor.yy0,&yymsp[-2].minor.yy0,&yymsp[0].minor.yy0,1);}
         break;
-      case 260: /* cmd ::= PRAGMA nm dbnm LP minus_num RP */
+      case 259: /* cmd ::= PRAGMA nm dbnm LP minus_num RP */
 {sqlite3Pragma(pParse,&yymsp[-4].minor.yy0,&yymsp[-3].minor.yy0,&yymsp[-1].minor.yy0,1);}
         break;
-      case 271: /* cmd ::= createkw trigger_decl BEGIN trigger_cmd_list END */
+      case 270: /* cmd ::= createkw trigger_decl BEGIN trigger_cmd_list END */
 {
   Token all;
   all.z = yymsp[-3].minor.yy0.z;
   all.n = (int)(yymsp[0].minor.yy0.z - yymsp[-3].minor.yy0.z) + yymsp[0].minor.yy0.n;
-  sqlite3FinishTrigger(pParse, yymsp[-1].minor.yy473, &all);
+  sqlite3FinishTrigger(pParse, yymsp[-1].minor.yy203, &all);
 }
         break;
-      case 272: /* trigger_decl ::= temp TRIGGER ifnotexists nm dbnm trigger_time trigger_event ON fullname foreach_clause when_clause */
+      case 271: /* trigger_decl ::= temp TRIGGER ifnotexists nm dbnm trigger_time trigger_event ON fullname foreach_clause when_clause */
 {
-  sqlite3BeginTrigger(pParse, &yymsp[-7].minor.yy0, &yymsp[-6].minor.yy0, yymsp[-5].minor.yy328, yymsp[-4].minor.yy378.a, yymsp[-4].minor.yy378.b, yymsp[-2].minor.yy65, yymsp[0].minor.yy132, yymsp[-10].minor.yy328, yymsp[-8].minor.yy328);
+  sqlite3BeginTrigger(pParse, &yymsp[-7].minor.yy0, &yymsp[-6].minor.yy0, yymsp[-5].minor.yy4, yymsp[-4].minor.yy90.a, yymsp[-4].minor.yy90.b, yymsp[-2].minor.yy259, yymsp[0].minor.yy314, yymsp[-10].minor.yy4, yymsp[-8].minor.yy4);
   yygotominor.yy0 = (yymsp[-6].minor.yy0.n==0?yymsp[-7].minor.yy0:yymsp[-6].minor.yy0);
 }
         break;
-      case 273: /* trigger_time ::= BEFORE */
-      case 276: /* trigger_time ::= */ yytestcase(yyruleno==276);
-{ yygotominor.yy328 = TK_BEFORE; }
+      case 272: /* trigger_time ::= BEFORE */
+      case 275: /* trigger_time ::= */ yytestcase(yyruleno==275);
+{ yygotominor.yy4 = TK_BEFORE; }
         break;
-      case 274: /* trigger_time ::= AFTER */
-{ yygotominor.yy328 = TK_AFTER;  }
+      case 273: /* trigger_time ::= AFTER */
+{ yygotominor.yy4 = TK_AFTER;  }
         break;
-      case 275: /* trigger_time ::= INSTEAD OF */
-{ yygotominor.yy328 = TK_INSTEAD;}
+      case 274: /* trigger_time ::= INSTEAD OF */
+{ yygotominor.yy4 = TK_INSTEAD;}
         break;
-      case 277: /* trigger_event ::= DELETE|INSERT */
-      case 278: /* trigger_event ::= UPDATE */ yytestcase(yyruleno==278);
-{yygotominor.yy378.a = yymsp[0].major; yygotominor.yy378.b = 0;}
+      case 276: /* trigger_event ::= DELETE|INSERT */
+      case 277: /* trigger_event ::= UPDATE */ yytestcase(yyruleno==277);
+{yygotominor.yy90.a = yymsp[0].major; yygotominor.yy90.b = 0;}
         break;
-      case 279: /* trigger_event ::= UPDATE OF inscollist */
-{yygotominor.yy378.a = TK_UPDATE; yygotominor.yy378.b = yymsp[0].minor.yy408;}
+      case 278: /* trigger_event ::= UPDATE OF inscollist */
+{yygotominor.yy90.a = TK_UPDATE; yygotominor.yy90.b = yymsp[0].minor.yy384;}
         break;
-      case 282: /* when_clause ::= */
-      case 304: /* key_opt ::= */ yytestcase(yyruleno==304);
-{ yygotominor.yy132 = 0; }
+      case 281: /* when_clause ::= */
+      case 303: /* key_opt ::= */ yytestcase(yyruleno==303);
+{ yygotominor.yy314 = 0; }
         break;
-      case 283: /* when_clause ::= WHEN expr */
-      case 305: /* key_opt ::= KEY expr */ yytestcase(yyruleno==305);
-{ yygotominor.yy132 = yymsp[0].minor.yy346.pExpr; }
+      case 282: /* when_clause ::= WHEN expr */
+      case 304: /* key_opt ::= KEY expr */ yytestcase(yyruleno==304);
+{ yygotominor.yy314 = yymsp[0].minor.yy118.pExpr; }
         break;
-      case 284: /* trigger_cmd_list ::= trigger_cmd_list trigger_cmd SEMI */
+      case 283: /* trigger_cmd_list ::= trigger_cmd_list trigger_cmd SEMI */
 {
-  assert( yymsp[-2].minor.yy473!=0 );
-  yymsp[-2].minor.yy473->pLast->pNext = yymsp[-1].minor.yy473;
-  yymsp[-2].minor.yy473->pLast = yymsp[-1].minor.yy473;
-  yygotominor.yy473 = yymsp[-2].minor.yy473;
+  assert( yymsp[-2].minor.yy203!=0 );
+  yymsp[-2].minor.yy203->pLast->pNext = yymsp[-1].minor.yy203;
+  yymsp[-2].minor.yy203->pLast = yymsp[-1].minor.yy203;
+  yygotominor.yy203 = yymsp[-2].minor.yy203;
 }
         break;
-      case 285: /* trigger_cmd_list ::= trigger_cmd SEMI */
+      case 284: /* trigger_cmd_list ::= trigger_cmd SEMI */
 { 
-  assert( yymsp[-1].minor.yy473!=0 );
-  yymsp[-1].minor.yy473->pLast = yymsp[-1].minor.yy473;
-  yygotominor.yy473 = yymsp[-1].minor.yy473;
+  assert( yymsp[-1].minor.yy203!=0 );
+  yymsp[-1].minor.yy203->pLast = yymsp[-1].minor.yy203;
+  yygotominor.yy203 = yymsp[-1].minor.yy203;
 }
         break;
-      case 287: /* trnm ::= nm DOT nm */
+      case 286: /* trnm ::= nm DOT nm */
 {
   yygotominor.yy0 = yymsp[0].minor.yy0;
   sqlite3ErrorMsg(pParse, 
@@ -100510,121 +102348,121 @@
         "statements within triggers");
 }
         break;
-      case 289: /* tridxby ::= INDEXED BY nm */
+      case 288: /* tridxby ::= INDEXED BY nm */
 {
   sqlite3ErrorMsg(pParse,
         "the INDEXED BY clause is not allowed on UPDATE or DELETE statements "
         "within triggers");
 }
         break;
-      case 290: /* tridxby ::= NOT INDEXED */
+      case 289: /* tridxby ::= NOT INDEXED */
 {
   sqlite3ErrorMsg(pParse,
         "the NOT INDEXED clause is not allowed on UPDATE or DELETE statements "
         "within triggers");
 }
         break;
-      case 291: /* trigger_cmd ::= UPDATE orconf trnm tridxby SET setlist where_opt */
-{ yygotominor.yy473 = sqlite3TriggerUpdateStep(pParse->db, &yymsp[-4].minor.yy0, yymsp[-1].minor.yy14, yymsp[0].minor.yy132, yymsp[-5].minor.yy186); }
+      case 290: /* trigger_cmd ::= UPDATE orconf trnm tridxby SET setlist where_opt */
+{ yygotominor.yy203 = sqlite3TriggerUpdateStep(pParse->db, &yymsp[-4].minor.yy0, yymsp[-1].minor.yy322, yymsp[0].minor.yy314, yymsp[-5].minor.yy210); }
         break;
-      case 292: /* trigger_cmd ::= insert_cmd INTO trnm inscollist_opt VALUES LP itemlist RP */
-{yygotominor.yy473 = sqlite3TriggerInsertStep(pParse->db, &yymsp[-5].minor.yy0, yymsp[-4].minor.yy408, yymsp[-1].minor.yy14, 0, yymsp[-7].minor.yy186);}
+      case 291: /* trigger_cmd ::= insert_cmd INTO trnm inscollist_opt VALUES LP itemlist RP */
+{yygotominor.yy203 = sqlite3TriggerInsertStep(pParse->db, &yymsp[-5].minor.yy0, yymsp[-4].minor.yy384, yymsp[-1].minor.yy322, 0, yymsp[-7].minor.yy210);}
         break;
-      case 293: /* trigger_cmd ::= insert_cmd INTO trnm inscollist_opt select */
-{yygotominor.yy473 = sqlite3TriggerInsertStep(pParse->db, &yymsp[-2].minor.yy0, yymsp[-1].minor.yy408, 0, yymsp[0].minor.yy3, yymsp[-4].minor.yy186);}
+      case 292: /* trigger_cmd ::= insert_cmd INTO trnm inscollist_opt select */
+{yygotominor.yy203 = sqlite3TriggerInsertStep(pParse->db, &yymsp[-2].minor.yy0, yymsp[-1].minor.yy384, 0, yymsp[0].minor.yy387, yymsp[-4].minor.yy210);}
         break;
-      case 294: /* trigger_cmd ::= DELETE FROM trnm tridxby where_opt */
-{yygotominor.yy473 = sqlite3TriggerDeleteStep(pParse->db, &yymsp[-2].minor.yy0, yymsp[0].minor.yy132);}
+      case 293: /* trigger_cmd ::= DELETE FROM trnm tridxby where_opt */
+{yygotominor.yy203 = sqlite3TriggerDeleteStep(pParse->db, &yymsp[-2].minor.yy0, yymsp[0].minor.yy314);}
         break;
-      case 295: /* trigger_cmd ::= select */
-{yygotominor.yy473 = sqlite3TriggerSelectStep(pParse->db, yymsp[0].minor.yy3); }
+      case 294: /* trigger_cmd ::= select */
+{yygotominor.yy203 = sqlite3TriggerSelectStep(pParse->db, yymsp[0].minor.yy387); }
         break;
-      case 296: /* expr ::= RAISE LP IGNORE RP */
+      case 295: /* expr ::= RAISE LP IGNORE RP */
 {
-  yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_RAISE, 0, 0, 0); 
-  if( yygotominor.yy346.pExpr ){
-    yygotominor.yy346.pExpr->affinity = OE_Ignore;
+  yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_RAISE, 0, 0, 0); 
+  if( yygotominor.yy118.pExpr ){
+    yygotominor.yy118.pExpr->affinity = OE_Ignore;
   }
-  yygotominor.yy346.zStart = yymsp[-3].minor.yy0.z;
-  yygotominor.yy346.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
+  yygotominor.yy118.zStart = yymsp[-3].minor.yy0.z;
+  yygotominor.yy118.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
 }
         break;
-      case 297: /* expr ::= RAISE LP raisetype COMMA nm RP */
+      case 296: /* expr ::= RAISE LP raisetype COMMA nm RP */
 {
-  yygotominor.yy346.pExpr = sqlite3PExpr(pParse, TK_RAISE, 0, 0, &yymsp[-1].minor.yy0); 
-  if( yygotominor.yy346.pExpr ) {
-    yygotominor.yy346.pExpr->affinity = (char)yymsp[-3].minor.yy328;
+  yygotominor.yy118.pExpr = sqlite3PExpr(pParse, TK_RAISE, 0, 0, &yymsp[-1].minor.yy0); 
+  if( yygotominor.yy118.pExpr ) {
+    yygotominor.yy118.pExpr->affinity = (char)yymsp[-3].minor.yy4;
   }
-  yygotominor.yy346.zStart = yymsp[-5].minor.yy0.z;
-  yygotominor.yy346.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
+  yygotominor.yy118.zStart = yymsp[-5].minor.yy0.z;
+  yygotominor.yy118.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
 }
         break;
-      case 298: /* raisetype ::= ROLLBACK */
-{yygotominor.yy328 = OE_Rollback;}
+      case 297: /* raisetype ::= ROLLBACK */
+{yygotominor.yy4 = OE_Rollback;}
         break;
-      case 300: /* raisetype ::= FAIL */
-{yygotominor.yy328 = OE_Fail;}
+      case 299: /* raisetype ::= FAIL */
+{yygotominor.yy4 = OE_Fail;}
         break;
-      case 301: /* cmd ::= DROP TRIGGER ifexists fullname */
+      case 300: /* cmd ::= DROP TRIGGER ifexists fullname */
 {
-  sqlite3DropTrigger(pParse,yymsp[0].minor.yy65,yymsp[-1].minor.yy328);
+  sqlite3DropTrigger(pParse,yymsp[0].minor.yy259,yymsp[-1].minor.yy4);
 }
         break;
-      case 302: /* cmd ::= ATTACH database_kw_opt expr AS expr key_opt */
+      case 301: /* cmd ::= ATTACH database_kw_opt expr AS expr key_opt */
 {
-  sqlite3Attach(pParse, yymsp[-3].minor.yy346.pExpr, yymsp[-1].minor.yy346.pExpr, yymsp[0].minor.yy132);
+  sqlite3Attach(pParse, yymsp[-3].minor.yy118.pExpr, yymsp[-1].minor.yy118.pExpr, yymsp[0].minor.yy314);
 }
         break;
-      case 303: /* cmd ::= DETACH database_kw_opt expr */
+      case 302: /* cmd ::= DETACH database_kw_opt expr */
 {
-  sqlite3Detach(pParse, yymsp[0].minor.yy346.pExpr);
+  sqlite3Detach(pParse, yymsp[0].minor.yy118.pExpr);
 }
         break;
-      case 308: /* cmd ::= REINDEX */
+      case 307: /* cmd ::= REINDEX */
 {sqlite3Reindex(pParse, 0, 0);}
         break;
-      case 309: /* cmd ::= REINDEX nm dbnm */
+      case 308: /* cmd ::= REINDEX nm dbnm */
 {sqlite3Reindex(pParse, &yymsp[-1].minor.yy0, &yymsp[0].minor.yy0);}
         break;
-      case 310: /* cmd ::= ANALYZE */
+      case 309: /* cmd ::= ANALYZE */
 {sqlite3Analyze(pParse, 0, 0);}
         break;
-      case 311: /* cmd ::= ANALYZE nm dbnm */
+      case 310: /* cmd ::= ANALYZE nm dbnm */
 {sqlite3Analyze(pParse, &yymsp[-1].minor.yy0, &yymsp[0].minor.yy0);}
         break;
-      case 312: /* cmd ::= ALTER TABLE fullname RENAME TO nm */
+      case 311: /* cmd ::= ALTER TABLE fullname RENAME TO nm */
 {
-  sqlite3AlterRenameTable(pParse,yymsp[-3].minor.yy65,&yymsp[0].minor.yy0);
+  sqlite3AlterRenameTable(pParse,yymsp[-3].minor.yy259,&yymsp[0].minor.yy0);
 }
         break;
-      case 313: /* cmd ::= ALTER TABLE add_column_fullname ADD kwcolumn_opt column */
+      case 312: /* cmd ::= ALTER TABLE add_column_fullname ADD kwcolumn_opt column */
 {
   sqlite3AlterFinishAddColumn(pParse, &yymsp[0].minor.yy0);
 }
         break;
-      case 314: /* add_column_fullname ::= fullname */
+      case 313: /* add_column_fullname ::= fullname */
 {
   pParse->db->lookaside.bEnabled = 0;
-  sqlite3AlterBeginAddColumn(pParse, yymsp[0].minor.yy65);
+  sqlite3AlterBeginAddColumn(pParse, yymsp[0].minor.yy259);
 }
         break;
-      case 317: /* cmd ::= create_vtab */
+      case 316: /* cmd ::= create_vtab */
 {sqlite3VtabFinishParse(pParse,0);}
         break;
-      case 318: /* cmd ::= create_vtab LP vtabarglist RP */
+      case 317: /* cmd ::= create_vtab LP vtabarglist RP */
 {sqlite3VtabFinishParse(pParse,&yymsp[0].minor.yy0);}
         break;
-      case 319: /* create_vtab ::= createkw VIRTUAL TABLE nm dbnm USING nm */
+      case 318: /* create_vtab ::= createkw VIRTUAL TABLE nm dbnm USING nm */
 {
     sqlite3VtabBeginParse(pParse, &yymsp[-3].minor.yy0, &yymsp[-2].minor.yy0, &yymsp[0].minor.yy0);
 }
         break;
-      case 322: /* vtabarg ::= */
+      case 321: /* vtabarg ::= */
 {sqlite3VtabArgInit(pParse);}
         break;
-      case 324: /* vtabargtoken ::= ANY */
-      case 325: /* vtabargtoken ::= lp anylist RP */ yytestcase(yyruleno==325);
-      case 326: /* lp ::= LP */ yytestcase(yyruleno==326);
+      case 323: /* vtabargtoken ::= ANY */
+      case 324: /* vtabargtoken ::= lp anylist RP */ yytestcase(yyruleno==324);
+      case 325: /* lp ::= LP */ yytestcase(yyruleno==325);
 {sqlite3VtabArgExtend(pParse,&yymsp[0].minor.yy0);}
         break;
       default:
@@ -100653,21 +102491,21 @@
       /* (91) conslist ::= conslist tcons */ yytestcase(yyruleno==91);
       /* (92) conslist ::= tcons */ yytestcase(yyruleno==92);
       /* (93) tcons ::= CONSTRAINT nm */ yytestcase(yyruleno==93);
-      /* (269) plus_opt ::= PLUS */ yytestcase(yyruleno==269);
-      /* (270) plus_opt ::= */ yytestcase(yyruleno==270);
-      /* (280) foreach_clause ::= */ yytestcase(yyruleno==280);
-      /* (281) foreach_clause ::= FOR EACH ROW */ yytestcase(yyruleno==281);
-      /* (288) tridxby ::= */ yytestcase(yyruleno==288);
-      /* (306) database_kw_opt ::= DATABASE */ yytestcase(yyruleno==306);
-      /* (307) database_kw_opt ::= */ yytestcase(yyruleno==307);
-      /* (315) kwcolumn_opt ::= */ yytestcase(yyruleno==315);
-      /* (316) kwcolumn_opt ::= COLUMNKW */ yytestcase(yyruleno==316);
-      /* (320) vtabarglist ::= vtabarg */ yytestcase(yyruleno==320);
-      /* (321) vtabarglist ::= vtabarglist COMMA vtabarg */ yytestcase(yyruleno==321);
-      /* (323) vtabarg ::= vtabarg vtabargtoken */ yytestcase(yyruleno==323);
-      /* (327) anylist ::= */ yytestcase(yyruleno==327);
-      /* (328) anylist ::= anylist LP anylist RP */ yytestcase(yyruleno==328);
-      /* (329) anylist ::= anylist ANY */ yytestcase(yyruleno==329);
+      /* (268) plus_opt ::= PLUS */ yytestcase(yyruleno==268);
+      /* (269) plus_opt ::= */ yytestcase(yyruleno==269);
+      /* (279) foreach_clause ::= */ yytestcase(yyruleno==279);
+      /* (280) foreach_clause ::= FOR EACH ROW */ yytestcase(yyruleno==280);
+      /* (287) tridxby ::= */ yytestcase(yyruleno==287);
+      /* (305) database_kw_opt ::= DATABASE */ yytestcase(yyruleno==305);
+      /* (306) database_kw_opt ::= */ yytestcase(yyruleno==306);
+      /* (314) kwcolumn_opt ::= */ yytestcase(yyruleno==314);
+      /* (315) kwcolumn_opt ::= COLUMNKW */ yytestcase(yyruleno==315);
+      /* (319) vtabarglist ::= vtabarg */ yytestcase(yyruleno==319);
+      /* (320) vtabarglist ::= vtabarglist COMMA vtabarg */ yytestcase(yyruleno==320);
+      /* (322) vtabarg ::= vtabarg vtabargtoken */ yytestcase(yyruleno==322);
+      /* (326) anylist ::= */ yytestcase(yyruleno==326);
+      /* (327) anylist ::= anylist LP anylist RP */ yytestcase(yyruleno==327);
+      /* (328) anylist ::= anylist ANY */ yytestcase(yyruleno==328);
         break;
   };
   yygoto = yyRuleInfo[yyruleno].lhs;
@@ -101695,7 +103533,7 @@
   }
 #endif
 #ifndef SQLITE_OMIT_VIRTUALTABLE
-  sqlite3DbFree(db, pParse->apVtabLock);
+  sqlite3_free(pParse->apVtabLock);
 #endif
 
   if( !IN_DECLARE_VTAB ){
@@ -101703,7 +103541,7 @@
     ** structure built up in pParse->pNewTable. The calling code (see vtab.c)
     ** will take responsibility for freeing the Table structure.
     */
-    sqlite3DeleteTable(pParse->pNewTable);
+    sqlite3DeleteTable(db, pParse->pNewTable);
   }
 
   sqlite3DeleteTrigger(db, pParse->pNewTrigger);
@@ -101717,7 +103555,7 @@
   while( pParse->pZombieTab ){
     Table *p = pParse->pZombieTab;
     pParse->pZombieTab = p->pNextZombie;
-    sqlite3DeleteTable(p);
+    sqlite3DeleteTable(db, p);
   }
   if( nErr>0 && pParse->rc==SQLITE_OK ){
     pParse->rc = SQLITE_ERROR;
@@ -102127,15 +103965,33 @@
 /************** Continuing where we left off in main.c ***********************/
 #endif
 
-/*
-** The version of the library
-*/
 #ifndef SQLITE_AMALGAMATION
+/* IMPLEMENTATION-OF: R-46656-45156 The sqlite3_version[] string constant
+** contains the text of SQLITE_VERSION macro. 
+*/
 SQLITE_API const char sqlite3_version[] = SQLITE_VERSION;
 #endif
+
+/* IMPLEMENTATION-OF: R-53536-42575 The sqlite3_libversion() function returns
+** a pointer to the to the sqlite3_version[] string constant. 
+*/
 SQLITE_API const char *sqlite3_libversion(void){ return sqlite3_version; }
+
+/* IMPLEMENTATION-OF: R-63124-39300 The sqlite3_sourceid() function returns a
+** pointer to a string constant whose value is the same as the
+** SQLITE_SOURCE_ID C preprocessor macro. 
+*/
 SQLITE_API const char *sqlite3_sourceid(void){ return SQLITE_SOURCE_ID; }
+
+/* IMPLEMENTATION-OF: R-35210-63508 The sqlite3_libversion_number() function
+** returns an integer equal to SQLITE_VERSION_NUMBER.
+*/
 SQLITE_API int sqlite3_libversion_number(void){ return SQLITE_VERSION_NUMBER; }
+
+/* IMPLEMENTATION-OF: R-54823-41343 The sqlite3_threadsafe() function returns
+** zero if and only if SQLite was compiled mutexing code omitted due to
+** the SQLITE_THREADSAFE compile-time option being set to 0.
+*/
 SQLITE_API int sqlite3_threadsafe(void){ return SQLITE_THREADSAFE; }
 
 #if !defined(SQLITE_OMIT_TRACE) && defined(SQLITE_ENABLE_IOTRACE)
@@ -102256,6 +104112,13 @@
   ** sqlite3_initialize().  The recursive calls normally come through
   ** sqlite3_os_init() when it invokes sqlite3_vfs_register(), but other
   ** recursive calls might also be possible.
+  **
+  ** IMPLEMENTATION-OF: R-00140-37445 SQLite automatically serializes calls
+  ** to the xInit method, so the xInit method need not be threadsafe.
+  **
+  ** The following mutex is what serializes access to the appdef pcache xInit
+  ** methods.  The sqlite3_pcache_methods.xInit() all is embedded in the
+  ** call to sqlite3PcacheInitialize().
   */
   sqlite3_mutex_enter(sqlite3GlobalConfig.pInitMutex);
   if( sqlite3GlobalConfig.isInit==0 && sqlite3GlobalConfig.inProgress==0 ){
@@ -102536,12 +104399,12 @@
     sz = 0;
     pStart = 0;
   }else if( pBuf==0 ){
-    sz = ROUND8(sz);
+    sz = ROUNDDOWN8(sz); /* IMP: R-33038-09382 */
     sqlite3BeginBenignMalloc();
-    pStart = sqlite3Malloc( sz*cnt );
+    pStart = sqlite3Malloc( sz*cnt );  /* IMP: R-61949-35727 */
     sqlite3EndBenignMalloc();
   }else{
-    sz = ROUNDDOWN8(sz);
+    sz = ROUNDDOWN8(sz); /* IMP: R-33038-09382 */
     pStart = pBuf;
   }
   db->lookaside.pStart = pStart;
@@ -102584,14 +104447,14 @@
   va_start(ap, op);
   switch( op ){
     case SQLITE_DBCONFIG_LOOKASIDE: {
-      void *pBuf = va_arg(ap, void*);
-      int sz = va_arg(ap, int);
-      int cnt = va_arg(ap, int);
+      void *pBuf = va_arg(ap, void*); /* IMP: R-21112-12275 */
+      int sz = va_arg(ap, int);       /* IMP: R-47871-25994 */
+      int cnt = va_arg(ap, int);      /* IMP: R-04460-53386 */
       rc = setupLookaside(db, pBuf, sz, cnt);
       break;
     }
     default: {
-      rc = SQLITE_ERROR;
+      rc = SQLITE_ERROR; /* IMP: R-42790-23372 */
       break;
     }
   }
@@ -102697,10 +104560,27 @@
 }
 
 /*
+** Invoke the destructor function associated with FuncDef p, if any. Except,
+** if this is not the last copy of the function, do not invoke it. Multiple
+** copies of a single function are created when create_function() is called
+** with SQLITE_ANY as the encoding.
+*/
+static void functionDestroy(sqlite3 *db, FuncDef *p){
+  FuncDestructor *pDestructor = p->pDestructor;
+  if( pDestructor ){
+    pDestructor->nRef--;
+    if( pDestructor->nRef==0 ){
+      pDestructor->xDestroy(pDestructor->pUserData);
+      sqlite3DbFree(db, pDestructor);
+    }
+  }
+}
+
+/*
 ** Close an existing SQLite database
 */
 SQLITE_API int sqlite3_close(sqlite3 *db){
-  HashElem *i;
+  HashElem *i;                    /* Hash table iterator */
   int j;
 
   if( !db ){
@@ -102768,6 +104648,7 @@
     for(p=db->aFunc.a[j]; p; p=pHash){
       pHash = p->pHash;
       while( p ){
+        functionDestroy(db, p);
         pNext = p->pNext;
         sqlite3DbFree(db, p);
         p = pNext;
@@ -103042,7 +104923,8 @@
   void *pUserData,
   void (*xFunc)(sqlite3_context*,int,sqlite3_value **),
   void (*xStep)(sqlite3_context*,int,sqlite3_value **),
-  void (*xFinal)(sqlite3_context*)
+  void (*xFinal)(sqlite3_context*),
+  FuncDestructor *pDestructor
 ){
   FuncDef *p;
   int nName;
@@ -103070,10 +104952,10 @@
   }else if( enc==SQLITE_ANY ){
     int rc;
     rc = sqlite3CreateFunc(db, zFunctionName, nArg, SQLITE_UTF8,
-         pUserData, xFunc, xStep, xFinal);
+         pUserData, xFunc, xStep, xFinal, pDestructor);
     if( rc==SQLITE_OK ){
       rc = sqlite3CreateFunc(db, zFunctionName, nArg, SQLITE_UTF16LE,
-          pUserData, xFunc, xStep, xFinal);
+          pUserData, xFunc, xStep, xFinal, pDestructor);
     }
     if( rc!=SQLITE_OK ){
       return rc;
@@ -103106,6 +104988,15 @@
   if( !p ){
     return SQLITE_NOMEM;
   }
+
+  /* If an older version of the function with a configured destructor is
+  ** being replaced invoke the destructor function here. */
+  functionDestroy(db, p);
+
+  if( pDestructor ){
+    pDestructor->nRef++;
+  }
+  p->pDestructor = pDestructor;
   p->flags = 0;
   p->xFunc = xFunc;
   p->xStep = xStep;
@@ -103120,7 +105011,7 @@
 */
 SQLITE_API int sqlite3_create_function(
   sqlite3 *db,
-  const char *zFunctionName,
+  const char *zFunc,
   int nArg,
   int enc,
   void *p,
@@ -103128,9 +105019,41 @@
   void (*xStep)(sqlite3_context*,int,sqlite3_value **),
   void (*xFinal)(sqlite3_context*)
 ){
-  int rc;
+  return sqlite3_create_function_v2(db, zFunc, nArg, enc, p, xFunc, xStep,
+                                    xFinal, 0);
+}
+
+SQLITE_API int sqlite3_create_function_v2(
+  sqlite3 *db,
+  const char *zFunc,
+  int nArg,
+  int enc,
+  void *p,
+  void (*xFunc)(sqlite3_context*,int,sqlite3_value **),
+  void (*xStep)(sqlite3_context*,int,sqlite3_value **),
+  void (*xFinal)(sqlite3_context*),
+  void (*xDestroy)(void *)
+){
+  int rc = SQLITE_ERROR;
+  FuncDestructor *pArg = 0;
   sqlite3_mutex_enter(db->mutex);
-  rc = sqlite3CreateFunc(db, zFunctionName, nArg, enc, p, xFunc, xStep, xFinal);
+  if( xDestroy ){
+    pArg = (FuncDestructor *)sqlite3DbMallocZero(db, sizeof(FuncDestructor));
+    if( !pArg ){
+      xDestroy(p);
+      goto out;
+    }
+    pArg->xDestroy = xDestroy;
+    pArg->pUserData = p;
+  }
+  rc = sqlite3CreateFunc(db, zFunc, nArg, enc, p, xFunc, xStep, xFinal, pArg);
+  if( pArg && pArg->nRef==0 ){
+    assert( rc!=SQLITE_OK );
+    xDestroy(p);
+    sqlite3DbFree(db, pArg);
+  }
+
+ out:
   rc = sqlite3ApiExit(db, rc);
   sqlite3_mutex_leave(db->mutex);
   return rc;
@@ -103152,7 +105075,7 @@
   sqlite3_mutex_enter(db->mutex);
   assert( !db->mallocFailed );
   zFunc8 = sqlite3Utf16to8(db, zFunctionName, -1, SQLITE_UTF16NATIVE);
-  rc = sqlite3CreateFunc(db, zFunc8, nArg, eTextRep, p, xFunc, xStep, xFinal);
+  rc = sqlite3CreateFunc(db, zFunc8, nArg, eTextRep, p, xFunc, xStep, xFinal,0);
   sqlite3DbFree(db, zFunc8);
   rc = sqlite3ApiExit(db, rc);
   sqlite3_mutex_leave(db->mutex);
@@ -103183,7 +105106,7 @@
   sqlite3_mutex_enter(db->mutex);
   if( sqlite3FindFunction(db, zName, nName, nArg, SQLITE_UTF8, 0)==0 ){
     sqlite3CreateFunc(db, zName, nArg, SQLITE_UTF8,
-                      0, sqlite3InvalidFunction, 0, 0);
+                      0, sqlite3InvalidFunction, 0, 0, 0);
   }
   rc = sqlite3ApiExit(db, SQLITE_OK);
   sqlite3_mutex_leave(db->mutex);
@@ -103321,7 +105244,10 @@
 ** configured by this function.
 */
 SQLITE_API int sqlite3_wal_autocheckpoint(sqlite3 *db, int nFrame){
-#ifndef SQLITE_OMIT_WAL
+#ifdef SQLITE_OMIT_WAL
+  UNUSED_PARAMETER(db);
+  UNUSED_PARAMETER(nFrame);
+#else
   if( nFrame>0 ){
     sqlite3_wal_hook(db, sqlite3WalDefaultHook, SQLITE_INT_TO_PTR(nFrame));
   }else{
@@ -103409,16 +105335,7 @@
 
   for(i=0; i<db->nDb && rc==SQLITE_OK; i++){
     if( i==iDb || iDb==SQLITE_MAX_ATTACHED ){
-      Btree *pBt = db->aDb[i].pBt;
-      if( pBt ){
-        if( sqlite3BtreeIsInReadTrans(pBt) ){
-          rc = SQLITE_LOCKED;
-        }else{
-          sqlite3BtreeEnter(pBt);
-          rc = sqlite3PagerCheckpoint(sqlite3BtreePager(pBt));
-          sqlite3BtreeLeave(pBt);
-        }
-      }
+      rc = sqlite3BtreeCheckpoint(db->aDb[i].pBt);
     }
   }
 
@@ -103461,60 +105378,6 @@
 }
 
 /*
-** This routine is called to create a connection to a database BTree
-** driver.  If zFilename is the name of a file, then that file is
-** opened and used.  If zFilename is the magic name ":memory:" then
-** the database is stored in memory (and is thus forgotten as soon as
-** the connection is closed.)  If zFilename is NULL then the database
-** is a "virtual" database for transient use only and is deleted as
-** soon as the connection is closed.
-**
-** A virtual database can be either a disk file (that is automatically
-** deleted when the file is closed) or it an be held entirely in memory.
-** The sqlite3TempInMemory() function is used to determine which.
-*/
-SQLITE_PRIVATE int sqlite3BtreeFactory(
-  sqlite3 *db,              /* Main database when opening aux otherwise 0 */
-  const char *zFilename,    /* Name of the file containing the BTree database */
-  int omitJournal,          /* if TRUE then do not journal this file */
-  int nCache,               /* How many pages in the page cache */
-  int vfsFlags,             /* Flags passed through to vfsOpen */
-  Btree **ppBtree           /* Pointer to new Btree object written here */
-){
-  int btFlags = 0;
-  int rc;
-  
-  assert( sqlite3_mutex_held(db->mutex) );
-  assert( ppBtree != 0);
-  if( omitJournal ){
-    btFlags |= BTREE_OMIT_JOURNAL;
-  }
-  if( db->flags & SQLITE_NoReadlock ){
-    btFlags |= BTREE_NO_READLOCK;
-  }
-#ifndef SQLITE_OMIT_MEMORYDB
-  if( zFilename==0 && sqlite3TempInMemory(db) ){
-    zFilename = ":memory:";
-  }
-#endif
-
-  if( (vfsFlags & SQLITE_OPEN_MAIN_DB)!=0 && (zFilename==0 || *zFilename==0) ){
-    vfsFlags = (vfsFlags & ~SQLITE_OPEN_MAIN_DB) | SQLITE_OPEN_TEMP_DB;
-  }
-  rc = sqlite3BtreeOpen(zFilename, (sqlite3 *)db, ppBtree, btFlags, vfsFlags);
-
-  /* If the B-Tree was successfully opened, set the pager-cache size to the
-  ** default value. Except, if the call to BtreeOpen() returned a handle
-  ** open on an existing shared pager-cache, do not change the pager-cache 
-  ** size.
-  */
-  if( rc==SQLITE_OK && 0==sqlite3BtreeSchema(*ppBtree, 0, 0) ){
-    sqlite3BtreeSetCacheSize(*ppBtree, nCache);
-  }
-  return rc;
-}
-
-/*
 ** Return UTF-8 encoded English language explanation of the most recent
 ** error.
 */
@@ -103756,17 +105619,39 @@
 */
 SQLITE_API int sqlite3_limit(sqlite3 *db, int limitId, int newLimit){
   int oldLimit;
+
+
+  /* EVIDENCE-OF: R-30189-54097 For each limit category SQLITE_LIMIT_NAME
+  ** there is a hard upper bound set at compile-time by a C preprocessor
+  ** macro called SQLITE_MAX_NAME. (The "_LIMIT_" in the name is changed to
+  ** "_MAX_".)
+  */
+  assert( aHardLimit[SQLITE_LIMIT_LENGTH]==SQLITE_MAX_LENGTH );
+  assert( aHardLimit[SQLITE_LIMIT_SQL_LENGTH]==SQLITE_MAX_SQL_LENGTH );
+  assert( aHardLimit[SQLITE_LIMIT_COLUMN]==SQLITE_MAX_COLUMN );
+  assert( aHardLimit[SQLITE_LIMIT_EXPR_DEPTH]==SQLITE_MAX_EXPR_DEPTH );
+  assert( aHardLimit[SQLITE_LIMIT_COMPOUND_SELECT]==SQLITE_MAX_COMPOUND_SELECT);
+  assert( aHardLimit[SQLITE_LIMIT_VDBE_OP]==SQLITE_MAX_VDBE_OP );
+  assert( aHardLimit[SQLITE_LIMIT_FUNCTION_ARG]==SQLITE_MAX_FUNCTION_ARG );
+  assert( aHardLimit[SQLITE_LIMIT_ATTACHED]==SQLITE_MAX_ATTACHED );
+  assert( aHardLimit[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]==
+                                               SQLITE_MAX_LIKE_PATTERN_LENGTH );
+  assert( aHardLimit[SQLITE_LIMIT_VARIABLE_NUMBER]==SQLITE_MAX_VARIABLE_NUMBER);
+  assert( aHardLimit[SQLITE_LIMIT_TRIGGER_DEPTH]==SQLITE_MAX_TRIGGER_DEPTH );
+  assert( SQLITE_LIMIT_TRIGGER_DEPTH==(SQLITE_N_LIMIT-1) );
+
+
   if( limitId<0 || limitId>=SQLITE_N_LIMIT ){
     return -1;
   }
   oldLimit = db->aLimit[limitId];
-  if( newLimit>=0 ){
+  if( newLimit>=0 ){                   /* IMP: R-52476-28732 */
     if( newLimit>aHardLimit[limitId] ){
-      newLimit = aHardLimit[limitId];
+      newLimit = aHardLimit[limitId];  /* IMP: R-51463-25634 */
     }
     db->aLimit[limitId] = newLimit;
   }
-  return oldLimit;
+  return oldLimit;                     /* IMP: R-53341-35419 */
 }
 
 /*
@@ -103790,6 +105675,24 @@
   if( rc ) return rc;
 #endif
 
+  /* Only allow sensible combinations of bits in the flags argument.  
+  ** Throw an error if any non-sense combination is used.  If we
+  ** do not block illegal combinations here, it could trigger
+  ** assert() statements in deeper layers.  Sensible combinations
+  ** are:
+  **
+  **  1:  SQLITE_OPEN_READONLY
+  **  2:  SQLITE_OPEN_READWRITE
+  **  6:  SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE
+  */
+  assert( SQLITE_OPEN_READONLY  == 0x01 );
+  assert( SQLITE_OPEN_READWRITE == 0x02 );
+  assert( SQLITE_OPEN_CREATE    == 0x04 );
+  testcase( (1<<(flags&7))==0x02 ); /* READONLY */
+  testcase( (1<<(flags&7))==0x04 ); /* READWRITE */
+  testcase( (1<<(flags&7))==0x40 ); /* READWRITE | CREATE */
+  if( ((1<<(flags&7)) & 0x46)==0 ) return SQLITE_MISUSE;
+
   if( sqlite3GlobalConfig.bCoreMutex==0 ){
     isThreadsafe = 0;
   }else if( flags & SQLITE_OPEN_NOMUTEX ){
@@ -103823,7 +105726,8 @@
                SQLITE_OPEN_SUBJOURNAL | 
                SQLITE_OPEN_MASTER_JOURNAL |
                SQLITE_OPEN_NOMUTEX |
-               SQLITE_OPEN_FULLMUTEX
+               SQLITE_OPEN_FULLMUTEX |
+               SQLITE_OPEN_WAL
              );
 
   /* Allocate the sqlite data structure */
@@ -103895,9 +105799,8 @@
 
   /* Open the backend database driver */
   db->openFlags = flags;
-  rc = sqlite3BtreeFactory(db, zFilename, 0, SQLITE_DEFAULT_CACHE_SIZE, 
-                           flags | SQLITE_OPEN_MAIN_DB,
-                           &db->aDb[0].pBt);
+  rc = sqlite3BtreeOpen(zFilename, db, &db->aDb[0].pBt, 0,
+                        flags | SQLITE_OPEN_MAIN_DB);
   if( rc!=SQLITE_OK ){
     if( rc==SQLITE_IOERR_NOMEM ){
       rc = SQLITE_NOMEM;
@@ -104604,6 +106507,22 @@
       break;
     }
 
+    /* sqlite3_test_control(SQLITE_TESTCTRL_SCRATCHMALLOC, sz, &pNew, pFree);
+    **
+    ** Pass pFree into sqlite3ScratchFree(). 
+    ** If sz>0 then allocate a scratch buffer into pNew.  
+    */
+    case SQLITE_TESTCTRL_SCRATCHMALLOC: {
+      void *pFree, **ppNew;
+      int sz;
+      sz = va_arg(ap, int);
+      ppNew = va_arg(ap, void**);
+      pFree = va_arg(ap, void*);
+      if( sz ) *ppNew = sqlite3ScratchMalloc(sz);
+      sqlite3ScratchFree(pFree);
+      break;
+    }
+
   }
   va_end(ap);
 #endif /* SQLITE_OMIT_BUILTIN_TEST */
@@ -104867,7 +106786,7 @@
       assert( aArg==aDyn || (aDyn==0 && aArg==aStatic) );
       assert( nArg<=(int)ArraySize(aStatic) || aArg==aDyn );
       if( (!aDyn && nArg==(int)ArraySize(aStatic))
-       || (aDyn && nArg==(int)(sqlite3DbMallocSize(db, aDyn)/sizeof(void*)))
+       || (aDyn && nArg==(int)(sqlite3MallocSize(aDyn)/sizeof(void*)))
       ){
         /* The aArg[] array needs to grow. */
         void **pNew = (void **)sqlite3Malloc(nArg*sizeof(void *)*2);
@@ -105792,6 +107711,7 @@
 SQLITE_PRIVATE int sqlite3Fts3AllSegdirs(Fts3Table*, sqlite3_stmt **);
 SQLITE_PRIVATE int sqlite3Fts3MatchinfoDocsizeLocal(Fts3Cursor*, u32*);
 SQLITE_PRIVATE int sqlite3Fts3MatchinfoDocsizeGlobal(Fts3Cursor*, u32*);
+SQLITE_PRIVATE int sqlite3Fts3ReadLock(Fts3Table *);
 
 /* Flags allowed as part of the 4th argument to SegmentReaderIterate() */
 #define FTS3_SEGMENT_REQUIRE_POS   0x00000001
@@ -107159,11 +109079,59 @@
 typedef struct TermSelect TermSelect;
 struct TermSelect {
   int isReqPos;
-  char *aOutput;                  /* Malloc'd output buffer */
-  int nOutput;                    /* Size of output in bytes */
+  char *aaOutput[16];             /* Malloc'd output buffer */
+  int anOutput[16];               /* Size of output in bytes */
 };
 
 /*
+** Merge all doclists in the TermSelect.aaOutput[] array into a single
+** doclist stored in TermSelect.aaOutput[0]. If successful, delete all
+** other doclists (except the aaOutput[0] one) and return SQLITE_OK.
+**
+** If an OOM error occurs, return SQLITE_NOMEM. In this case it is
+** the responsibility of the caller to free any doclists left in the
+** TermSelect.aaOutput[] array.
+*/
+static int fts3TermSelectMerge(TermSelect *pTS){
+  int mergetype = (pTS->isReqPos ? MERGE_POS_OR : MERGE_OR);
+  char *aOut = 0;
+  int nOut = 0;
+  int i;
+
+  /* Loop through the doclists in the aaOutput[] array. Merge them all
+  ** into a single doclist.
+  */
+  for(i=0; i<SizeofArray(pTS->aaOutput); i++){
+    if( pTS->aaOutput[i] ){
+      if( !aOut ){
+        aOut = pTS->aaOutput[i];
+        nOut = pTS->anOutput[i];
+        pTS->aaOutput[0] = 0;
+      }else{
+        int nNew = nOut + pTS->anOutput[i];
+        char *aNew = sqlite3_malloc(nNew);
+        if( !aNew ){
+          sqlite3_free(aOut);
+          return SQLITE_NOMEM;
+        }
+        fts3DoclistMerge(mergetype, 0, 0,
+            aNew, &nNew, pTS->aaOutput[i], pTS->anOutput[i], aOut, nOut
+        );
+        sqlite3_free(pTS->aaOutput[i]);
+        sqlite3_free(aOut);
+        pTS->aaOutput[i] = 0;
+        aOut = aNew;
+        nOut = nNew;
+      }
+    }
+  }
+
+  pTS->aaOutput[0] = aOut;
+  pTS->anOutput[0] = nOut;
+  return SQLITE_OK;
+}
+
+/*
 ** This function is used as the sqlite3Fts3SegReaderIterate() callback when
 ** querying the full-text index for a doclist associated with a term or
 ** term-prefix.
@@ -107177,38 +109145,63 @@
   int nDoclist
 ){
   TermSelect *pTS = (TermSelect *)pContext;
-  int nNew = pTS->nOutput + nDoclist;
-  char *aNew = sqlite3_malloc(nNew);
 
   UNUSED_PARAMETER(p);
   UNUSED_PARAMETER(zTerm);
   UNUSED_PARAMETER(nTerm);
 
-  if( !aNew ){
-    return SQLITE_NOMEM;
-  }
-
-  if( pTS->nOutput==0 ){
+  if( pTS->aaOutput[0]==0 ){
     /* If this is the first term selected, copy the doclist to the output
     ** buffer using memcpy(). TODO: Add a way to transfer control of the
     ** aDoclist buffer from the caller so as to avoid the memcpy().
     */
-    memcpy(aNew, aDoclist, nDoclist);
+    pTS->aaOutput[0] = sqlite3_malloc(nDoclist);
+    pTS->anOutput[0] = nDoclist;
+    if( pTS->aaOutput[0] ){
+      memcpy(pTS->aaOutput[0], aDoclist, nDoclist);
+    }else{
+      return SQLITE_NOMEM;
+    }
   }else{
-    /* The output buffer is not empty. Merge doclist aDoclist with the
-    ** existing output. This can only happen with prefix-searches (as
-    ** searches for exact terms return exactly one doclist).
-    */
     int mergetype = (pTS->isReqPos ? MERGE_POS_OR : MERGE_OR);
-    fts3DoclistMerge(mergetype, 0, 0,
-        aNew, &nNew, pTS->aOutput, pTS->nOutput, aDoclist, nDoclist
-    );
+    char *aMerge = aDoclist;
+    int nMerge = nDoclist;
+    int iOut;
+
+    for(iOut=0; iOut<SizeofArray(pTS->aaOutput); iOut++){
+      char *aNew;
+      int nNew;
+      if( pTS->aaOutput[iOut]==0 ){
+        assert( iOut>0 );
+        pTS->aaOutput[iOut] = aMerge;
+        pTS->anOutput[iOut] = nMerge;
+        break;
+      }
+
+      nNew = nMerge + pTS->anOutput[iOut];
+      aNew = sqlite3_malloc(nNew);
+      if( !aNew ){
+        if( aMerge!=aDoclist ){
+          sqlite3_free(aMerge);
+        }
+        return SQLITE_NOMEM;
+      }
+      fts3DoclistMerge(mergetype, 0, 0,
+          aNew, &nNew, pTS->aaOutput[iOut], pTS->anOutput[iOut], aMerge, nMerge
+      );
+
+      if( iOut>0 ) sqlite3_free(aMerge);
+      sqlite3_free(pTS->aaOutput[iOut]);
+      pTS->aaOutput[iOut] = 0;
+
+      aMerge = aNew;
+      nMerge = nNew;
+      if( (iOut+1)==SizeofArray(pTS->aaOutput) ){
+        pTS->aaOutput[iOut] = aMerge;
+        pTS->anOutput[iOut] = nMerge;
+      }
+    }
   }
-
-  sqlite3_free(pTS->aOutput);
-  pTS->aOutput = aNew;
-  pTS->nOutput = nNew;
-
   return SQLITE_OK;
 }
 
@@ -107332,12 +109325,17 @@
   rc = sqlite3Fts3SegReaderIterate(p, apSegment, nSegment, &filter,
       fts3TermSelectCb, (void *)&tsc
   );
+  if( rc==SQLITE_OK ){
+    rc = fts3TermSelectMerge(&tsc);
+  }
 
   if( rc==SQLITE_OK ){
-    *ppOut = tsc.aOutput;
-    *pnOut = tsc.nOutput;
+    *ppOut = tsc.aaOutput[0];
+    *pnOut = tsc.anOutput[0];
   }else{
-    sqlite3_free(tsc.aOutput);
+    for(i=0; i<SizeofArray(tsc.aaOutput); i++){
+      sqlite3_free(tsc.aaOutput[i]);
+    }
   }
 
 finished:
@@ -107663,6 +109661,9 @@
       return rc;
     }
 
+    rc = sqlite3Fts3ReadLock(p);
+    if( rc!=SQLITE_OK ) return rc;
+
     rc = evalFts3Expr(p, pCsr->pExpr, &pCsr->aDoclist, &pCsr->nDoclist, 0);
     pCsr->pNextId = pCsr->aDoclist;
     pCsr->iPrevId = 0;
@@ -108041,11 +110042,14 @@
   const char *zName               /* New name of table */
 ){
   Fts3Table *p = (Fts3Table *)pVtab;
-  sqlite3 *db;                    /* Database connection */
+  sqlite3 *db = p->db;            /* Database connection */
   int rc;                         /* Return Code */
- 
-  db = p->db;
-  rc = SQLITE_OK;
+
+  rc = sqlite3Fts3PendingTermsFlush(p);
+  if( rc!=SQLITE_OK ){
+    return rc;
+  }
+
   fts3DbExec(&rc, db,
     "ALTER TABLE %Q.'%q_content'  RENAME TO '%q_content';",
     p->zDb, p->zName, zName
@@ -108113,7 +110117,7 @@
 ** used to retrieve the respective implementations.
 **
 ** Calling sqlite3Fts3SimpleTokenizerModule() sets the value pointed
-** to by the argument to point a the "simple" tokenizer implementation.
+** to by the argument to point to the "simple" tokenizer implementation.
 ** Function ...PorterTokenizerModule() sets *pModule to point to the
 ** porter tokenizer/stemmer implementation.
 */
@@ -108315,7 +110319,7 @@
 ** negative values).
 */
 static int fts3isspace(char c){
-  return (c&0x80)==0 ? isspace(c) : 0;
+  return c==' ' || c=='\t' || c=='\n' || c=='\r' || c=='\v' || c=='\f';
 }
 
 /*
@@ -110702,6 +112706,9 @@
 static int simpleDelim(simple_tokenizer *t, unsigned char c){
   return c<0x80 && t->delim[c];
 }
+static int fts3_isalnum(int x){
+  return (x>='0' && x<='9') || (x>='A' && x<='Z') || (x>='a' && x<='z');
+}
 
 /*
 ** Create a new tokenizer instance.
@@ -110736,7 +112743,7 @@
     /* Mark non-alphanumeric ASCII characters as delimiters */
     int i;
     for(i=1; i<0x80; i++){
-      t->delim[i] = !isalnum(i) ? -1 : 0;
+      t->delim[i] = !fts3_isalnum(i) ? -1 : 0;
     }
   }
 
@@ -110842,7 +112849,7 @@
         ** case-insensitivity.
         */
         unsigned char ch = p[iStartOffset+i];
-        c->pToken[i] = (char)(ch<0x80 ? tolower(ch) : ch);
+        c->pToken[i] = (char)((ch>='A' && ch<='Z') ? ch-'A'+'a' : ch);
       }
       *ppToken = c->pToken;
       *pnBytes = n;
@@ -111203,6 +113210,36 @@
 }
 
 /*
+** This function ensures that the caller has obtained a shared-cache
+** table-lock on the %_content table. This is required before reading
+** data from the fts3 table. If this lock is not acquired first, then
+** the caller may end up holding read-locks on the %_segments and %_segdir
+** tables, but no read-lock on the %_content table. If this happens 
+** a second connection will be able to write to the fts3 table, but
+** attempting to commit those writes might return SQLITE_LOCKED or
+** SQLITE_LOCKED_SHAREDCACHE (because the commit attempts to obtain 
+** write-locks on the %_segments and %_segdir ** tables). 
+**
+** We try to avoid this because if FTS3 returns any error when committing
+** a transaction, the whole transaction will be rolled back. And this is
+** not what users expect when they get SQLITE_LOCKED_SHAREDCACHE. It can
+** still happen if the user reads data directly from the %_segments or
+** %_segdir tables instead of going through FTS3 though.
+*/
+SQLITE_PRIVATE int sqlite3Fts3ReadLock(Fts3Table *p){
+  int rc;                         /* Return code */
+  sqlite3_stmt *pStmt;            /* Statement used to obtain lock */
+
+  rc = fts3SqlStmt(p, SQL_SELECT_CONTENT_BY_ROWID, &pStmt, 0);
+  if( rc==SQLITE_OK ){
+    sqlite3_bind_null(pStmt, 1);
+    sqlite3_step(pStmt);
+    rc = sqlite3_reset(pStmt);
+  }
+  return rc;
+}
+
+/*
 ** Set *ppStmt to a statement handle that may be used to iterate through
 ** all rows in the %_segdir table, from oldest to newest. If successful,
 ** return SQLITE_OK. If an error occurs while preparing the statement, 
@@ -114693,6 +116730,45 @@
 ** algorithms packaged as an SQLite virtual table module.
 */
 
+/*
+** Database Format of R-Tree Tables
+** --------------------------------
+**
+** The data structure for a single virtual r-tree table is stored in three 
+** native SQLite tables declared as follows. In each case, the '%' character
+** in the table name is replaced with the user-supplied name of the r-tree
+** table.
+**
+**   CREATE TABLE %_node(nodeno INTEGER PRIMARY KEY, data BLOB)
+**   CREATE TABLE %_parent(nodeno INTEGER PRIMARY KEY, parentnode INTEGER)
+**   CREATE TABLE %_rowid(rowid INTEGER PRIMARY KEY, nodeno INTEGER)
+**
+** The data for each node of the r-tree structure is stored in the %_node
+** table. For each node that is not the root node of the r-tree, there is
+** an entry in the %_parent table associating the node with its parent.
+** And for each row of data in the table, there is an entry in the %_rowid
+** table that maps from the entries rowid to the id of the node that it
+** is stored on.
+**
+** The root node of an r-tree always exists, even if the r-tree table is
+** empty. The nodeno of the root node is always 1. All other nodes in the
+** table must be the same size as the root node. The content of each node
+** is formatted as follows:
+**
+**   1. If the node is the root node (node 1), then the first 2 bytes
+**      of the node contain the tree depth as a big-endian integer.
+**      For non-root nodes, the first 2 bytes are left unused.
+**
+**   2. The next 2 bytes contain the number of entries currently 
+**      stored in the node.
+**
+**   3. The remainder of the node contains the node entries. Each entry
+**      consists of a single 8-byte integer followed by an even number
+**      of 4-byte coordinates. For leaf nodes the integer is the rowid
+**      of a record. For internal nodes it is the node number of a
+**      child page.
+*/
+
 #if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_RTREE)
 
 /*
@@ -114733,6 +116809,9 @@
   #define AssignCells splitNodeStartree
 #endif
 
+#if !defined(NDEBUG) && !defined(SQLITE_DEBUG) 
+# define NDEBUG 1
+#endif
 
 #ifndef SQLITE_CORE
   SQLITE_EXTENSION_INIT1
@@ -114741,6 +116820,7 @@
 
 
 #ifndef SQLITE_AMALGAMATION
+#include "sqlite3rtree.h"
 typedef sqlite3_int64 i64;
 typedef unsigned char u8;
 typedef unsigned int u32;
@@ -114751,6 +116831,8 @@
 typedef struct RtreeNode RtreeNode;
 typedef struct RtreeCell RtreeCell;
 typedef struct RtreeConstraint RtreeConstraint;
+typedef struct RtreeMatchArg RtreeMatchArg;
+typedef struct RtreeGeomCallback RtreeGeomCallback;
 typedef union RtreeCoord RtreeCoord;
 
 /* The rtree may have between 1 and RTREE_MAX_DIMENSIONS dimensions. */
@@ -114820,6 +116902,15 @@
 #define RTREE_REINSERT(p) RTREE_MINCELLS(p)
 #define RTREE_MAXCELLS 51
 
+/*
+** The smallest possible node-size is (512-64)==448 bytes. And the largest
+** supported cell size is 48 bytes (8 byte rowid + ten 4 byte coordinates).
+** Therefore all non-root nodes must contain at least 3 entries. Since 
+** 2^40 is greater than 2^64, an r-tree structure always has a depth of
+** 40 or less.
+*/
+#define RTREE_MAX_DEPTH 40
+
 /* 
 ** An rtree cursor object.
 */
@@ -114852,35 +116943,23 @@
 ** A search constraint.
 */
 struct RtreeConstraint {
-  int iCoord;                       /* Index of constrained coordinate */
-  int op;                           /* Constraining operation */
-  double rValue;                    /* Constraint value. */
+  int iCoord;                     /* Index of constrained coordinate */
+  int op;                         /* Constraining operation */
+  double rValue;                  /* Constraint value. */
+  int (*xGeom)(sqlite3_rtree_geometry *, int, double *, int *);
+  sqlite3_rtree_geometry *pGeom;  /* Constraint callback argument for a MATCH */
 };
 
 /* Possible values for RtreeConstraint.op */
-#define RTREE_EQ 0x41
-#define RTREE_LE 0x42
-#define RTREE_LT 0x43
-#define RTREE_GE 0x44
-#define RTREE_GT 0x45
+#define RTREE_EQ    0x41
+#define RTREE_LE    0x42
+#define RTREE_LT    0x43
+#define RTREE_GE    0x44
+#define RTREE_GT    0x45
+#define RTREE_MATCH 0x46
 
 /* 
 ** An rtree structure node.
-**
-** Data format (RtreeNode.zData):
-**
-**   1. If the node is the root node (node 1), then the first 2 bytes
-**      of the node contain the tree depth as a big-endian integer.
-**      For non-root nodes, the first 2 bytes are left unused.
-**
-**   2. The next 2 bytes contain the number of entries currently 
-**      stored in the node.
-**
-**   3. The remainder of the node contains the node entries. Each entry
-**      consists of a single 8-byte integer followed by an even number
-**      of 4-byte coordinates. For leaf nodes the integer is the rowid
-**      of a record. For internal nodes it is the node number of a
-**      child page.
 */
 struct RtreeNode {
   RtreeNode *pParent;               /* Parent node */
@@ -114900,6 +116979,40 @@
   RtreeCoord aCoord[RTREE_MAX_DIMENSIONS*2];
 };
 
+
+/*
+** Value for the first field of every RtreeMatchArg object. The MATCH
+** operator tests that the first field of a blob operand matches this
+** value to avoid operating on invalid blobs (which could cause a segfault).
+*/
+#define RTREE_GEOMETRY_MAGIC 0x891245AB
+
+/*
+** An instance of this structure must be supplied as a blob argument to
+** the right-hand-side of an SQL MATCH operator used to constrain an
+** r-tree query.
+*/
+struct RtreeMatchArg {
+  u32 magic;                      /* Always RTREE_GEOMETRY_MAGIC */
+  int (*xGeom)(sqlite3_rtree_geometry *, int, double *, int *);
+  void *pContext;
+  int nParam;
+  double aParam[1];
+};
+
+/*
+** When a geometry callback is created (see sqlite3_rtree_geometry_callback),
+** a single instance of the following structure is allocated. It is used
+** as the context for the user-function created by by s_r_g_c(). The object
+** is eventually deleted by the destructor mechanism provided by
+** sqlite3_create_function_v2() (which is called by s_r_g_c() to create
+** the geometry callback function).
+*/
+struct RtreeGeomCallback {
+  int (*xGeom)(sqlite3_rtree_geometry *, int, double *, int *);
+  void *pContext;
+};
+
 #ifndef MAX
 # define MAX(x,y) ((x) < (y) ? (y) : (x))
 #endif
@@ -114982,10 +117095,8 @@
 ** Clear the content of node p (set all bytes to 0x00).
 */
 static void nodeZero(Rtree *pRtree, RtreeNode *p){
-  if( p ){
-    memset(&p->zData[2], 0, pRtree->iNodeSize-2);
-    p->isDirty = 1;
-  }
+  memset(&p->zData[2], 0, pRtree->iNodeSize-2);
+  p->isDirty = 1;
 }
 
 /*
@@ -115005,7 +117116,6 @@
 */
 static RtreeNode *nodeHashLookup(Rtree *pRtree, i64 iNode){
   RtreeNode *p;
-  assert( iNode!=0 );
   for(p=pRtree->aHash[nodeHash(iNode)]; p && p->iNode!=iNode; p=p->pNext);
   return p;
 }
@@ -115014,13 +117124,11 @@
 ** Add node pNode to the node hash table.
 */
 static void nodeHashInsert(Rtree *pRtree, RtreeNode *pNode){
-  if( pNode ){
-    int iHash;
-    assert( pNode->pNext==0 );
-    iHash = nodeHash(pNode->iNode);
-    pNode->pNext = pRtree->aHash[iHash];
-    pRtree->aHash[iHash] = pNode;
-  }
+  int iHash;
+  assert( pNode->pNext==0 );
+  iHash = nodeHash(pNode->iNode);
+  pNode->pNext = pRtree->aHash[iHash];
+  pRtree->aHash[iHash] = pNode;
 }
 
 /*
@@ -115042,11 +117150,11 @@
 ** assigned a node number when nodeWrite() is called to write the
 ** node contents out to the database.
 */
-static RtreeNode *nodeNew(Rtree *pRtree, RtreeNode *pParent, int zero){
+static RtreeNode *nodeNew(Rtree *pRtree, RtreeNode *pParent){
   RtreeNode *pNode;
   pNode = (RtreeNode *)sqlite3_malloc(sizeof(RtreeNode) + pRtree->iNodeSize);
   if( pNode ){
-    memset(pNode, 0, sizeof(RtreeNode) + (zero?pRtree->iNodeSize:0));
+    memset(pNode, 0, sizeof(RtreeNode) + pRtree->iNodeSize);
     pNode->zData = (u8 *)&pNode[1];
     pNode->nRef = 1;
     pNode->pParent = pParent;
@@ -115067,6 +117175,7 @@
   RtreeNode **ppNode         /* OUT: Acquired node */
 ){
   int rc;
+  int rc2 = SQLITE_OK;
   RtreeNode *pNode;
 
   /* Check if the requested node is already in the hash table. If so,
@@ -115083,40 +117192,64 @@
     return SQLITE_OK;
   }
 
-  pNode = (RtreeNode *)sqlite3_malloc(sizeof(RtreeNode) + pRtree->iNodeSize);
-  if( !pNode ){
-    *ppNode = 0;
-    return SQLITE_NOMEM;
-  }
-  pNode->pParent = pParent;
-  pNode->zData = (u8 *)&pNode[1];
-  pNode->nRef = 1;
-  pNode->iNode = iNode;
-  pNode->isDirty = 0;
-  pNode->pNext = 0;
-
   sqlite3_bind_int64(pRtree->pReadNode, 1, iNode);
   rc = sqlite3_step(pRtree->pReadNode);
   if( rc==SQLITE_ROW ){
     const u8 *zBlob = sqlite3_column_blob(pRtree->pReadNode, 0);
-    assert( sqlite3_column_bytes(pRtree->pReadNode, 0)==pRtree->iNodeSize );
-    memcpy(pNode->zData, zBlob, pRtree->iNodeSize);
-    nodeReference(pParent);
+    if( pRtree->iNodeSize==sqlite3_column_bytes(pRtree->pReadNode, 0) ){
+      pNode = (RtreeNode *)sqlite3_malloc(sizeof(RtreeNode)+pRtree->iNodeSize);
+      if( !pNode ){
+        rc2 = SQLITE_NOMEM;
+      }else{
+        pNode->pParent = pParent;
+        pNode->zData = (u8 *)&pNode[1];
+        pNode->nRef = 1;
+        pNode->iNode = iNode;
+        pNode->isDirty = 0;
+        pNode->pNext = 0;
+        memcpy(pNode->zData, zBlob, pRtree->iNodeSize);
+        nodeReference(pParent);
+      }
+    }
+  }
+  rc = sqlite3_reset(pRtree->pReadNode);
+  if( rc==SQLITE_OK ) rc = rc2;
+
+  /* If the root node was just loaded, set pRtree->iDepth to the height
+  ** of the r-tree structure. A height of zero means all data is stored on
+  ** the root node. A height of one means the children of the root node
+  ** are the leaves, and so on. If the depth as specified on the root node
+  ** is greater than RTREE_MAX_DEPTH, the r-tree structure must be corrupt.
+  */
+  if( pNode && iNode==1 ){
+    pRtree->iDepth = readInt16(pNode->zData);
+    if( pRtree->iDepth>RTREE_MAX_DEPTH ){
+      rc = SQLITE_CORRUPT;
+    }
+  }
+
+  /* If no error has occurred so far, check if the "number of entries"
+  ** field on the node is too large. If so, set the return code to 
+  ** SQLITE_CORRUPT.
+  */
+  if( pNode && rc==SQLITE_OK ){
+    if( NCELL(pNode)>((pRtree->iNodeSize-4)/pRtree->nBytesPerCell) ){
+      rc = SQLITE_CORRUPT;
+    }
+  }
+
+  if( rc==SQLITE_OK ){
+    if( pNode!=0 ){
+      nodeHashInsert(pRtree, pNode);
+    }else{
+      rc = SQLITE_CORRUPT;
+    }
+    *ppNode = pNode;
   }else{
     sqlite3_free(pNode);
-    pNode = 0;
+    *ppNode = 0;
   }
 
-  *ppNode = pNode;
-  rc = sqlite3_reset(pRtree->pReadNode);
-
-  if( rc==SQLITE_OK && iNode==1 ){
-    pRtree->iDepth = readInt16(pNode->zData);
-  }
-
-  assert( (rc==SQLITE_OK && pNode) || (pNode==0 && rc!=SQLITE_OK) );
-  nodeHashInsert(pRtree, pNode);
-
   return rc;
 }
 
@@ -115168,8 +117301,7 @@
   nMaxCell = (pRtree->iNodeSize-4)/pRtree->nBytesPerCell;
   nCell = NCELL(pNode);
 
-  assert(nCell<=nMaxCell);
-
+  assert( nCell<=nMaxCell );
   if( nCell<nMaxCell ){
     nodeOverwriteCell(pRtree, pNode, pCell, nCell);
     writeInt16(&pNode->zData[2], nCell+1);
@@ -115389,6 +117521,25 @@
   return rc;
 }
 
+
+/*
+** Free the RtreeCursor.aConstraint[] array and its contents.
+*/
+static void freeCursorConstraints(RtreeCursor *pCsr){
+  if( pCsr->aConstraint ){
+    int i;                        /* Used to iterate through constraint array */
+    for(i=0; i<pCsr->nConstraint; i++){
+      sqlite3_rtree_geometry *pGeom = pCsr->aConstraint[i].pGeom;
+      if( pGeom ){
+        if( pGeom->xDelUser ) pGeom->xDelUser(pGeom->pUser);
+        sqlite3_free(pGeom);
+      }
+    }
+    sqlite3_free(pCsr->aConstraint);
+    pCsr->aConstraint = 0;
+  }
+}
+
 /* 
 ** Rtree virtual table module xClose method.
 */
@@ -115396,7 +117547,7 @@
   Rtree *pRtree = (Rtree *)(cur->pVtab);
   int rc;
   RtreeCursor *pCsr = (RtreeCursor *)cur;
-  sqlite3_free(pCsr->aConstraint);
+  freeCursorConstraints(pCsr);
   rc = nodeRelease(pRtree, pCsr->pNode);
   sqlite3_free(pCsr);
   return rc;
@@ -115413,13 +117564,39 @@
   return (pCsr->pNode==0);
 }
 
+/*
+** The r-tree constraint passed as the second argument to this function is
+** guaranteed to be a MATCH constraint.
+*/
+static int testRtreeGeom(
+  Rtree *pRtree,                  /* R-Tree object */
+  RtreeConstraint *pConstraint,   /* MATCH constraint to test */
+  RtreeCell *pCell,               /* Cell to test */
+  int *pbRes                      /* OUT: Test result */
+){
+  int i;
+  double aCoord[RTREE_MAX_DIMENSIONS*2];
+  int nCoord = pRtree->nDim*2;
+
+  assert( pConstraint->op==RTREE_MATCH );
+  assert( pConstraint->pGeom );
+
+  for(i=0; i<nCoord; i++){
+    aCoord[i] = DCOORD(pCell->aCoord[i]);
+  }
+  return pConstraint->xGeom(pConstraint->pGeom, nCoord, aCoord, pbRes);
+}
+
 /* 
 ** Cursor pCursor currently points to a cell in a non-leaf page.
-** Return true if the sub-tree headed by the cell is filtered
+** Set *pbEof to true if the sub-tree headed by the cell is filtered
 ** (excluded) by the constraints in the pCursor->aConstraint[] 
 ** array, or false otherwise.
+**
+** Return SQLITE_OK if successful or an SQLite error code if an error
+** occurs within a geometry callback.
 */
-static int testRtreeCell(Rtree *pRtree, RtreeCursor *pCursor){
+static int testRtreeCell(Rtree *pRtree, RtreeCursor *pCursor, int *pbEof){
   RtreeCell cell;
   int ii;
   int bRes = 0;
@@ -115431,31 +117608,55 @@
     double cell_max = DCOORD(cell.aCoord[(p->iCoord>>1)*2+1]);
 
     assert(p->op==RTREE_LE || p->op==RTREE_LT || p->op==RTREE_GE 
-        || p->op==RTREE_GT || p->op==RTREE_EQ
+        || p->op==RTREE_GT || p->op==RTREE_EQ || p->op==RTREE_MATCH
     );
 
     switch( p->op ){
-      case RTREE_LE: case RTREE_LT: bRes = p->rValue<cell_min; break;
-      case RTREE_GE: case RTREE_GT: bRes = p->rValue>cell_max; break;
-      case RTREE_EQ: 
+      case RTREE_LE: case RTREE_LT: 
+        bRes = p->rValue<cell_min; 
+        break;
+
+      case RTREE_GE: case RTREE_GT: 
+        bRes = p->rValue>cell_max; 
+        break;
+
+      case RTREE_EQ:
         bRes = (p->rValue>cell_max || p->rValue<cell_min);
         break;
+
+      default: {
+        int rc;
+        assert( p->op==RTREE_MATCH );
+        rc = testRtreeGeom(pRtree, p, &cell, &bRes);
+        if( rc!=SQLITE_OK ){
+          return rc;
+        }
+        bRes = !bRes;
+        break;
+      }
     }
   }
 
-  return bRes;
+  *pbEof = bRes;
+  return SQLITE_OK;
 }
 
 /* 
-** Return true if the cell that cursor pCursor currently points to
+** Test if the cell that cursor pCursor currently points to
 ** would be filtered (excluded) by the constraints in the 
-** pCursor->aConstraint[] array, or false otherwise.
+** pCursor->aConstraint[] array. If so, set *pbEof to true before
+** returning. If the cell is not filtered (excluded) by the constraints,
+** set pbEof to zero.
+**
+** Return SQLITE_OK if successful or an SQLite error code if an error
+** occurs within a geometry callback.
 **
 ** This function assumes that the cell is part of a leaf node.
 */
-static int testRtreeEntry(Rtree *pRtree, RtreeCursor *pCursor){
+static int testRtreeEntry(Rtree *pRtree, RtreeCursor *pCursor, int *pbEof){
   RtreeCell cell;
   int ii;
+  *pbEof = 0;
 
   nodeGetCell(pRtree, pCursor->pNode, pCursor->iCell, &cell);
   for(ii=0; ii<pCursor->nConstraint; ii++){
@@ -115463,7 +117664,7 @@
     double coord = DCOORD(cell.aCoord[p->iCoord]);
     int res;
     assert(p->op==RTREE_LE || p->op==RTREE_LT || p->op==RTREE_GE 
-        || p->op==RTREE_GT || p->op==RTREE_EQ
+        || p->op==RTREE_GT || p->op==RTREE_EQ || p->op==RTREE_MATCH
     );
     switch( p->op ){
       case RTREE_LE: res = (coord<=p->rValue); break;
@@ -115471,12 +117672,24 @@
       case RTREE_GE: res = (coord>=p->rValue); break;
       case RTREE_GT: res = (coord>p->rValue);  break;
       case RTREE_EQ: res = (coord==p->rValue); break;
+      default: {
+        int rc;
+        assert( p->op==RTREE_MATCH );
+        rc = testRtreeGeom(pRtree, p, &cell, &res);
+        if( rc!=SQLITE_OK ){
+          return rc;
+        }
+        break;
+      }
     }
 
-    if( !res ) return 1;
+    if( !res ){
+      *pbEof = 1;
+      return SQLITE_OK;
+    }
   }
 
-  return 0;
+  return SQLITE_OK;
 }
 
 /*
@@ -115503,13 +117716,13 @@
   assert( iHeight>=0 );
 
   if( iHeight==0 ){
-    isEof = testRtreeEntry(pRtree, pCursor);
+    rc = testRtreeEntry(pRtree, pCursor, &isEof);
   }else{
-    isEof = testRtreeCell(pRtree, pCursor);
+    rc = testRtreeCell(pRtree, pCursor, &isEof);
   }
-  if( isEof || iHeight==0 ){
+  if( rc!=SQLITE_OK || isEof || iHeight==0 ){
     *pEof = isEof;
-    return SQLITE_OK;
+    return rc;
   }
 
   iRowid = nodeGetRowid(pRtree, pCursor->pNode, pCursor->iCell);
@@ -115545,24 +117758,34 @@
 ** One of the cells in node pNode is guaranteed to have a 64-bit 
 ** integer value equal to iRowid. Return the index of this cell.
 */
-static int nodeRowidIndex(Rtree *pRtree, RtreeNode *pNode, i64 iRowid){
+static int nodeRowidIndex(
+  Rtree *pRtree, 
+  RtreeNode *pNode, 
+  i64 iRowid,
+  int *piIndex
+){
   int ii;
-  for(ii=0; nodeGetRowid(pRtree, pNode, ii)!=iRowid; ii++){
-    assert( ii<(NCELL(pNode)-1) );
+  int nCell = NCELL(pNode);
+  for(ii=0; ii<nCell; ii++){
+    if( nodeGetRowid(pRtree, pNode, ii)==iRowid ){
+      *piIndex = ii;
+      return SQLITE_OK;
+    }
   }
-  return ii;
+  return SQLITE_CORRUPT;
 }
 
 /*
 ** Return the index of the cell containing a pointer to node pNode
 ** in its parent. If pNode is the root node, return -1.
 */
-static int nodeParentIndex(Rtree *pRtree, RtreeNode *pNode){
+static int nodeParentIndex(Rtree *pRtree, RtreeNode *pNode, int *piIndex){
   RtreeNode *pParent = pNode->pParent;
   if( pParent ){
-    return nodeRowidIndex(pRtree, pParent, pNode->iNode);
+    return nodeRowidIndex(pRtree, pParent, pNode->iNode, piIndex);
   }
-  return -1;
+  *piIndex = -1;
+  return SQLITE_OK;
 }
 
 /* 
@@ -115573,13 +117796,17 @@
   RtreeCursor *pCsr = (RtreeCursor *)pVtabCursor;
   int rc = SQLITE_OK;
 
+  /* RtreeCursor.pNode must not be NULL. If is is NULL, then this cursor is
+  ** already at EOF. It is against the rules to call the xNext() method of
+  ** a cursor that has already reached EOF.
+  */
+  assert( pCsr->pNode );
+
   if( pCsr->iStrategy==1 ){
     /* This "scan" is a direct lookup by rowid. There is no next entry. */
     nodeRelease(pRtree, pCsr->pNode);
     pCsr->pNode = 0;
-  }
-
-  else if( pCsr->pNode ){
+  }else{
     /* Move to the next entry that matches the configured constraints. */
     int iHeight = 0;
     while( pCsr->pNode ){
@@ -115593,7 +117820,10 @@
         }
       }
       pCsr->pNode = pNode->pParent;
-      pCsr->iCell = nodeParentIndex(pRtree, pNode);
+      rc = nodeParentIndex(pRtree, pNode, &pCsr->iCell);
+      if( rc!=SQLITE_OK ){
+        return rc;
+      }
       nodeReference(pCsr->pNode);
       nodeRelease(pRtree, pNode);
       iHeight++;
@@ -115661,6 +117891,51 @@
   return rc;
 }
 
+/*
+** This function is called to configure the RtreeConstraint object passed
+** as the second argument for a MATCH constraint. The value passed as the
+** first argument to this function is the right-hand operand to the MATCH
+** operator.
+*/
+static int deserializeGeometry(sqlite3_value *pValue, RtreeConstraint *pCons){
+  RtreeMatchArg *p;
+  sqlite3_rtree_geometry *pGeom;
+  int nBlob;
+
+  /* Check that value is actually a blob. */
+  if( !sqlite3_value_type(pValue)==SQLITE_BLOB ) return SQLITE_ERROR;
+
+  /* Check that the blob is roughly the right size. */
+  nBlob = sqlite3_value_bytes(pValue);
+  if( nBlob<sizeof(RtreeMatchArg) 
+   || ((nBlob-sizeof(RtreeMatchArg))%sizeof(double))!=0
+  ){
+    return SQLITE_ERROR;
+  }
+
+  pGeom = (sqlite3_rtree_geometry *)sqlite3_malloc(
+      sizeof(sqlite3_rtree_geometry) + nBlob
+  );
+  if( !pGeom ) return SQLITE_NOMEM;
+  memset(pGeom, 0, sizeof(sqlite3_rtree_geometry));
+  p = (RtreeMatchArg *)&pGeom[1];
+
+  memcpy(p, sqlite3_value_blob(pValue), nBlob);
+  if( p->magic!=RTREE_GEOMETRY_MAGIC 
+   || nBlob!=(sizeof(RtreeMatchArg) + (p->nParam-1)*sizeof(double))
+  ){
+    sqlite3_free(pGeom);
+    return SQLITE_ERROR;
+  }
+
+  pGeom->pContext = p->pContext;
+  pGeom->nParam = p->nParam;
+  pGeom->aParam = p->aParam;
+
+  pCons->xGeom = p->xGeom;
+  pCons->pGeom = pGeom;
+  return SQLITE_OK;
+}
 
 /* 
 ** Rtree virtual table module xFilter method.
@@ -115679,8 +117954,7 @@
 
   rtreeReference(pRtree);
 
-  sqlite3_free(pCsr->aConstraint);
-  pCsr->aConstraint = 0;
+  freeCursorConstraints(pCsr);
   pCsr->iStrategy = idxNum;
 
   if( idxNum==1 ){
@@ -115689,8 +117963,9 @@
     i64 iRowid = sqlite3_value_int64(argv[0]);
     rc = findLeafNode(pRtree, iRowid, &pLeaf);
     pCsr->pNode = pLeaf; 
-    if( pLeaf && rc==SQLITE_OK ){
-      pCsr->iCell = nodeRowidIndex(pRtree, pLeaf, iRowid);
+    if( pLeaf ){
+      assert( rc==SQLITE_OK );
+      rc = nodeRowidIndex(pRtree, pLeaf, iRowid, &pCsr->iCell);
     }
   }else{
     /* Normal case - r-tree scan. Set up the RtreeCursor.aConstraint array 
@@ -115702,12 +117977,24 @@
       if( !pCsr->aConstraint ){
         rc = SQLITE_NOMEM;
       }else{
+        memset(pCsr->aConstraint, 0, sizeof(RtreeConstraint)*argc);
         assert( (idxStr==0 && argc==0) || strlen(idxStr)==argc*2 );
         for(ii=0; ii<argc; ii++){
           RtreeConstraint *p = &pCsr->aConstraint[ii];
           p->op = idxStr[ii*2];
           p->iCoord = idxStr[ii*2+1]-'a';
-          p->rValue = sqlite3_value_double(argv[ii]);
+          if( p->op==RTREE_MATCH ){
+            /* A MATCH operator. The right-hand-side must be a blob that
+            ** can be cast into an RtreeMatchArg object. One created using
+            ** an sqlite3_rtree_geometry_callback() SQL user function.
+            */
+            rc = deserializeGeometry(argv[ii], p);
+            if( rc!=SQLITE_OK ){
+              break;
+            }
+          }else{
+            p->rValue = sqlite3_value_double(argv[ii]);
+          }
         }
       }
     }
@@ -115748,11 +118035,10 @@
 **   idxNum     idxStr        Strategy
 **   ------------------------------------------------
 **     1        Unused        Direct lookup by rowid.
-**     2        See below     R-tree query.
-**     3        Unused        Full table scan.
+**     2        See below     R-tree query or full-table scan.
 **   ------------------------------------------------
 **
-** If strategy 1 or 3 is used, then idxStr is not meaningful. If strategy
+** If strategy 1 is used, then idxStr is not meaningful. If strategy
 ** 2 is used, idxStr is formatted to contain 2 bytes for each 
 ** constraint used. The first two bytes of idxStr correspond to 
 ** the constraint in sqlite3_index_info.aConstraintUsage[] with
@@ -115768,6 +118054,7 @@
 **      <        0x43 ('C')
 **     >=        0x44 ('D')
 **      >        0x45 ('E')
+**   MATCH       0x46 ('F')
 **   ----------------------
 **
 ** The second of each pair of bytes identifies the coordinate column
@@ -115806,7 +118093,9 @@
       return SQLITE_OK;
     }
 
-    if( p->usable && p->iColumn>0 ){
+    if( p->usable && (p->iColumn>0 || p->op==SQLITE_INDEX_CONSTRAINT_MATCH) ){
+      int j, opmsk;
+      static const unsigned char compatible[] = { 0, 0, 1, 1, 2, 2 };
       u8 op = 0;
       switch( p->op ){
         case SQLITE_INDEX_CONSTRAINT_EQ: op = RTREE_EQ; break;
@@ -115814,31 +118103,33 @@
         case SQLITE_INDEX_CONSTRAINT_LE: op = RTREE_LE; break;
         case SQLITE_INDEX_CONSTRAINT_LT: op = RTREE_LT; break;
         case SQLITE_INDEX_CONSTRAINT_GE: op = RTREE_GE; break;
+        default:
+          assert( p->op==SQLITE_INDEX_CONSTRAINT_MATCH );
+          op = RTREE_MATCH; 
+          break;
       }
-      if( op ){
-        /* Make sure this particular constraint has not been used before.
-        ** If it has been used before, ignore it.
-        **
-        ** A <= or < can be used if there is a prior >= or >.
-        ** A >= or > can be used if there is a prior < or <=.
-        ** A <= or < is disqualified if there is a prior <=, <, or ==.
-        ** A >= or > is disqualified if there is a prior >=, >, or ==.
-        ** A == is disqualifed if there is any prior constraint.
-        */
-        int j, opmsk;
-        static const unsigned char compatible[] = { 0, 0, 1, 1, 2, 2 };
-        assert( compatible[RTREE_EQ & 7]==0 );
-        assert( compatible[RTREE_LT & 7]==1 );
-        assert( compatible[RTREE_LE & 7]==1 );
-        assert( compatible[RTREE_GT & 7]==2 );
-        assert( compatible[RTREE_GE & 7]==2 );
-        cCol = p->iColumn - 1 + 'a';
-        opmsk = compatible[op & 7];
-        for(j=0; j<iIdx; j+=2){
-          if( zIdxStr[j+1]==cCol && (compatible[zIdxStr[j] & 7] & opmsk)!=0 ){
-            op = 0;
-            break;
-          }
+      assert( op!=0 );
+
+      /* Make sure this particular constraint has not been used before.
+      ** If it has been used before, ignore it.
+      **
+      ** A <= or < can be used if there is a prior >= or >.
+      ** A >= or > can be used if there is a prior < or <=.
+      ** A <= or < is disqualified if there is a prior <=, <, or ==.
+      ** A >= or > is disqualified if there is a prior >=, >, or ==.
+      ** A == is disqualifed if there is any prior constraint.
+      */
+      assert( compatible[RTREE_EQ & 7]==0 );
+      assert( compatible[RTREE_LT & 7]==1 );
+      assert( compatible[RTREE_LE & 7]==1 );
+      assert( compatible[RTREE_GT & 7]==2 );
+      assert( compatible[RTREE_GE & 7]==2 );
+      cCol = p->iColumn - 1 + 'a';
+      opmsk = compatible[op & 7];
+      for(j=0; j<iIdx; j+=2){
+        if( zIdxStr[j+1]==cCol && (compatible[zIdxStr[j] & 7] & opmsk)!=0 ){
+          op = 0;
+          break;
         }
       }
       if( op ){
@@ -115946,7 +118237,12 @@
   int ii;
   float overlap = 0.0;
   for(ii=0; ii<nCell; ii++){
-    if( ii!=iExclude ){
+#if VARIANT_RSTARTREE_CHOOSESUBTREE
+    if( ii!=iExclude )
+#else
+    assert( iExclude==-1 );
+#endif
+    {
       int jj;
       float o = 1.0;
       for(jj=0; jj<(pRtree->nDim*2); jj+=2){
@@ -116039,22 +118335,31 @@
     ** the smallest area.
     */
     for(iCell=0; iCell<nCell; iCell++){
+      int bBest = 0;
       float growth;
       float area;
       float overlap = 0.0;
       nodeGetCell(pRtree, pNode, iCell, &cell);
       growth = cellGrowth(pRtree, &cell, pCell);
       area = cellArea(pRtree, &cell);
+
 #if VARIANT_RSTARTREE_CHOOSESUBTREE
       if( ii==(pRtree->iDepth-1) ){
         overlap = cellOverlapEnlargement(pRtree,&cell,pCell,aCell,nCell,iCell);
       }
-#endif
       if( (iCell==0) 
        || (overlap<fMinOverlap) 
        || (overlap==fMinOverlap && growth<fMinGrowth)
        || (overlap==fMinOverlap && growth==fMinGrowth && area<fMinArea)
       ){
+        bBest = 1;
+      }
+#else
+      if( iCell==0||growth<fMinGrowth||(growth==fMinGrowth && area<fMinArea) ){
+        bBest = 1;
+      }
+#endif
+      if( bBest ){
         fMinOverlap = overlap;
         fMinGrowth = growth;
         fMinArea = area;
@@ -116077,16 +118382,20 @@
 ** the node pNode. This function updates the bounding box cells in
 ** all ancestor elements.
 */
-static void AdjustTree(
+static int AdjustTree(
   Rtree *pRtree,                    /* Rtree table */
   RtreeNode *pNode,                 /* Adjust ancestry of this node. */
   RtreeCell *pCell                  /* This cell was just inserted */
 ){
   RtreeNode *p = pNode;
   while( p->pParent ){
-    RtreeCell cell;
     RtreeNode *pParent = p->pParent;
-    int iCell = nodeParentIndex(pRtree, p);
+    RtreeCell cell;
+    int iCell;
+
+    if( nodeParentIndex(pRtree, p, &iCell) ){
+      return SQLITE_CORRUPT;
+    }
 
     nodeGetCell(pRtree, pParent, iCell, &cell);
     if( !cellContains(pRtree, &cell, pCell) ){
@@ -116096,6 +118405,7 @@
  
     p = pParent;
   }
+  return SQLITE_OK;
 }
 
 /*
@@ -116624,14 +118934,14 @@
   nCell++;
 
   if( pNode->iNode==1 ){
-    pRight = nodeNew(pRtree, pNode, 1);
-    pLeft = nodeNew(pRtree, pNode, 1);
+    pRight = nodeNew(pRtree, pNode);
+    pLeft = nodeNew(pRtree, pNode);
     pRtree->iDepth++;
     pNode->isDirty = 1;
     writeInt16(pNode->zData, pRtree->iDepth);
   }else{
     pLeft = pNode;
-    pRight = nodeNew(pRtree, pLeft->pParent, 1);
+    pRight = nodeNew(pRtree, pLeft->pParent);
     nodeReference(pLeft);
   }
 
@@ -116648,8 +118958,12 @@
     goto splitnode_out;
   }
 
-  /* Ensure both child nodes have node numbers assigned to them. */
-  if( (0==pRight->iNode && SQLITE_OK!=(rc = nodeWrite(pRtree, pRight)))
+  /* Ensure both child nodes have node numbers assigned to them by calling
+  ** nodeWrite(). Node pRight always needs a node number, as it was created
+  ** by nodeNew() above. But node pLeft sometimes already has a node number.
+  ** In this case avoid the all to nodeWrite().
+  */
+  if( SQLITE_OK!=(rc = nodeWrite(pRtree, pRight))
    || (0==pLeft->iNode && SQLITE_OK!=(rc = nodeWrite(pRtree, pLeft)))
   ){
     goto splitnode_out;
@@ -116665,9 +118979,15 @@
     }
   }else{
     RtreeNode *pParent = pLeft->pParent;
-    int iCell = nodeParentIndex(pRtree, pLeft);
-    nodeOverwriteCell(pRtree, pParent, &leftbbox, iCell);
-    AdjustTree(pRtree, pParent, &leftbbox);
+    int iCell;
+    rc = nodeParentIndex(pRtree, pLeft, &iCell);
+    if( rc==SQLITE_OK ){
+      nodeOverwriteCell(pRtree, pParent, &leftbbox, iCell);
+      rc = AdjustTree(pRtree, pParent, &leftbbox);
+    }
+    if( rc!=SQLITE_OK ){
+      goto splitnode_out;
+    }
   }
   if( (rc = rtreeInsertCell(pRtree, pRight->pParent, &rightbbox, iHeight+1)) ){
     goto splitnode_out;
@@ -116711,20 +119031,43 @@
   return rc;
 }
 
+/*
+** If node pLeaf is not the root of the r-tree and its pParent pointer is 
+** still NULL, load all ancestor nodes of pLeaf into memory and populate
+** the pLeaf->pParent chain all the way up to the root node.
+**
+** This operation is required when a row is deleted (or updated - an update
+** is implemented as a delete followed by an insert). SQLite provides the
+** rowid of the row to delete, which can be used to find the leaf on which
+** the entry resides (argument pLeaf). Once the leaf is located, this 
+** function is called to determine its ancestry.
+*/
 static int fixLeafParent(Rtree *pRtree, RtreeNode *pLeaf){
   int rc = SQLITE_OK;
-  if( pLeaf->iNode!=1 && pLeaf->pParent==0 ){
-    sqlite3_bind_int64(pRtree->pReadParent, 1, pLeaf->iNode);
-    if( sqlite3_step(pRtree->pReadParent)==SQLITE_ROW ){
-      i64 iNode = sqlite3_column_int64(pRtree->pReadParent, 0);
-      rc = nodeAcquire(pRtree, iNode, 0, &pLeaf->pParent);
-    }else{
-      rc = SQLITE_ERROR;
+  RtreeNode *pChild = pLeaf;
+  while( rc==SQLITE_OK && pChild->iNode!=1 && pChild->pParent==0 ){
+    int rc2 = SQLITE_OK;          /* sqlite3_reset() return code */
+    sqlite3_bind_int64(pRtree->pReadParent, 1, pChild->iNode);
+    rc = sqlite3_step(pRtree->pReadParent);
+    if( rc==SQLITE_ROW ){
+      RtreeNode *pTest;           /* Used to test for reference loops */
+      i64 iNode;                  /* Node number of parent node */
+
+      /* Before setting pChild->pParent, test that we are not creating a
+      ** loop of references (as we would if, say, pChild==pParent). We don't
+      ** want to do this as it leads to a memory leak when trying to delete
+      ** the referenced counted node structures.
+      */
+      iNode = sqlite3_column_int64(pRtree->pReadParent, 0);
+      for(pTest=pLeaf; pTest && pTest->iNode!=iNode; pTest=pTest->pParent);
+      if( !pTest ){
+        rc2 = nodeAcquire(pRtree, iNode, 0, &pChild->pParent);
+      }
     }
-    sqlite3_reset(pRtree->pReadParent);
-    if( rc==SQLITE_OK ){
-      rc = fixLeafParent(pRtree, pLeaf->pParent);
-    }
+    rc = sqlite3_reset(pRtree->pReadParent);
+    if( rc==SQLITE_OK ) rc = rc2;
+    if( rc==SQLITE_OK && !pChild->pParent ) rc = SQLITE_CORRUPT;
+    pChild = pChild->pParent;
   }
   return rc;
 }
@@ -116733,18 +119076,24 @@
 
 static int removeNode(Rtree *pRtree, RtreeNode *pNode, int iHeight){
   int rc;
+  int rc2;
   RtreeNode *pParent;
   int iCell;
 
   assert( pNode->nRef==1 );
 
   /* Remove the entry in the parent cell. */
-  iCell = nodeParentIndex(pRtree, pNode);
-  pParent = pNode->pParent;
-  pNode->pParent = 0;
-  if( SQLITE_OK!=(rc = deleteCell(pRtree, pParent, iCell, iHeight+1)) 
-   || SQLITE_OK!=(rc = nodeRelease(pRtree, pParent))
-  ){
+  rc = nodeParentIndex(pRtree, pNode, &iCell);
+  if( rc==SQLITE_OK ){
+    pParent = pNode->pParent;
+    pNode->pParent = 0;
+    rc = deleteCell(pRtree, pParent, iCell, iHeight+1);
+  }
+  rc2 = nodeRelease(pRtree, pParent);
+  if( rc==SQLITE_OK ){
+    rc = rc2;
+  }
+  if( rc!=SQLITE_OK ){
     return rc;
   }
 
@@ -116774,8 +119123,9 @@
   return SQLITE_OK;
 }
 
-static void fixBoundingBox(Rtree *pRtree, RtreeNode *pNode){
+static int fixBoundingBox(Rtree *pRtree, RtreeNode *pNode){
   RtreeNode *pParent = pNode->pParent;
+  int rc = SQLITE_OK; 
   if( pParent ){
     int ii; 
     int nCell = NCELL(pNode);
@@ -116787,10 +119137,13 @@
       cellUnion(pRtree, &box, &cell);
     }
     box.iRowid = pNode->iNode;
-    ii = nodeParentIndex(pRtree, pNode);
-    nodeOverwriteCell(pRtree, pParent, &box, ii);
-    fixBoundingBox(pRtree, pParent);
+    rc = nodeParentIndex(pRtree, pNode, &ii);
+    if( rc==SQLITE_OK ){
+      nodeOverwriteCell(pRtree, pParent, &box, ii);
+      rc = fixBoundingBox(pRtree, pParent);
+    }
   }
+  return rc;
 }
 
 /*
@@ -116798,6 +119151,7 @@
 ** cell, adjust the r-tree data structure if required.
 */
 static int deleteCell(Rtree *pRtree, RtreeNode *pNode, int iCell, int iHeight){
+  RtreeNode *pParent;
   int rc;
 
   if( SQLITE_OK!=(rc = fixLeafParent(pRtree, pNode)) ){
@@ -116814,14 +119168,13 @@
   ** cell in the parent node so that it tightly contains the updated
   ** node.
   */
-  if( pNode->iNode!=1 ){
-    RtreeNode *pParent = pNode->pParent;
-    if( (pParent->iNode!=1 || NCELL(pParent)!=1) 
-     && (NCELL(pNode)<RTREE_MINCELLS(pRtree))
-    ){
+  pParent = pNode->pParent;
+  assert( pParent || pNode->iNode==1 );
+  if( pParent ){
+    if( NCELL(pNode)<RTREE_MINCELLS(pRtree) ){
       rc = removeNode(pRtree, pNode, iHeight);
     }else{
-      fixBoundingBox(pRtree, pNode);
+      rc = fixBoundingBox(pRtree, pNode);
     }
   }
 
@@ -116904,7 +119257,7 @@
     }
   }
   if( rc==SQLITE_OK ){
-    fixBoundingBox(pRtree, pNode);
+    rc = fixBoundingBox(pRtree, pNode);
   }
   for(; rc==SQLITE_OK && ii<nCell; ii++){
     /* Find a node to store this cell in. pNode->iNode currently contains
@@ -116958,11 +119311,13 @@
     rc = SplitNode(pRtree, pNode, pCell, iHeight);
 #endif
   }else{
-    AdjustTree(pRtree, pNode, pCell);
-    if( iHeight==0 ){
-      rc = rowidWrite(pRtree, pCell->iRowid, pNode->iNode);
-    }else{
-      rc = parentWrite(pRtree, pCell->iRowid, pNode->iNode);
+    rc = AdjustTree(pRtree, pNode, pCell);
+    if( rc==SQLITE_OK ){
+      if( iHeight==0 ){
+        rc = rowidWrite(pRtree, pCell->iRowid, pNode->iNode);
+      }else{
+        rc = parentWrite(pRtree, pCell->iRowid, pNode->iNode);
+      }
     }
   }
   return rc;
@@ -117032,7 +119387,6 @@
   rtreeReference(pRtree);
 
   assert(nData>=1);
-  assert(hashIsEmpty(pRtree));
 
   /* If azData[0] is not an SQL NULL value, it is the rowid of a
   ** record to delete from the r-tree table. The following block does
@@ -117058,8 +119412,10 @@
     /* Delete the cell in question from the leaf node. */
     if( rc==SQLITE_OK ){
       int rc2;
-      iCell = nodeRowidIndex(pRtree, pLeaf, iDelete);
-      rc = deleteCell(pRtree, pLeaf, iCell, 0);
+      rc = nodeRowidIndex(pRtree, pLeaf, iDelete, &iCell);
+      if( rc==SQLITE_OK ){
+        rc = deleteCell(pRtree, pLeaf, iCell, 0);
+      }
       rc2 = nodeRelease(pRtree, pLeaf);
       if( rc==SQLITE_OK ){
         rc = rc2;
@@ -117081,19 +119437,20 @@
     ** the root node (the operation that Gutman's paper says to perform 
     ** in this scenario).
     */
-    if( rc==SQLITE_OK && pRtree->iDepth>0 ){
-      if( rc==SQLITE_OK && NCELL(pRoot)==1 ){
-        RtreeNode *pChild;
-        i64 iChild = nodeGetRowid(pRtree, pRoot, 0);
-        rc = nodeAcquire(pRtree, iChild, pRoot, &pChild);
-        if( rc==SQLITE_OK ){
-          rc = removeNode(pRtree, pChild, pRtree->iDepth-1);
-        }
-        if( rc==SQLITE_OK ){
-          pRtree->iDepth--;
-          writeInt16(pRoot->zData, pRtree->iDepth);
-          pRoot->isDirty = 1;
-        }
+    if( rc==SQLITE_OK && pRtree->iDepth>0 && NCELL(pRoot)==1 ){
+      int rc2;
+      RtreeNode *pChild;
+      i64 iChild = nodeGetRowid(pRtree, pRoot, 0);
+      rc = nodeAcquire(pRtree, iChild, pRoot, &pChild);
+      if( rc==SQLITE_OK ){
+        rc = removeNode(pRtree, pChild, pRtree->iDepth-1);
+      }
+      rc2 = nodeRelease(pRtree, pChild);
+      if( rc==SQLITE_OK ) rc = rc2;
+      if( rc==SQLITE_OK ){
+        pRtree->iDepth--;
+        writeInt16(pRoot->zData, pRtree->iDepth);
+        pRoot->isDirty = 1;
       }
     }
 
@@ -117383,7 +119740,7 @@
   Rtree *pRtree;
   int nDb;              /* Length of string argv[1] */
   int nName;            /* Length of string argv[2] */
-  int eCoordType = (int)pAux;
+  int eCoordType = (pAux ? RTREE_COORD_INT32 : RTREE_COORD_REAL32);
 
   const char *aErrMsg[] = {
     0,                                                    /* 0 */
@@ -117529,12 +119886,10 @@
 ** function "rtreenode".
 */
 SQLITE_PRIVATE int sqlite3RtreeInit(sqlite3 *db){
-  int rc = SQLITE_OK;
+  const int utf8 = SQLITE_UTF8;
+  int rc;
 
-  if( rc==SQLITE_OK ){
-    int utf8 = SQLITE_UTF8;
-    rc = sqlite3_create_function(db, "rtreenode", 2, utf8, 0, rtreenode, 0, 0);
-  }
+  rc = sqlite3_create_function(db, "rtreenode", 2, utf8, 0, rtreenode, 0, 0);
   if( rc==SQLITE_OK ){
     int utf8 = SQLITE_UTF8;
     rc = sqlite3_create_function(db, "rtreedepth", 1, utf8, 0,rtreedepth, 0, 0);
@@ -117551,6 +119906,70 @@
   return rc;
 }
 
+/*
+** A version of sqlite3_free() that can be used as a callback. This is used
+** in two places - as the destructor for the blob value returned by the
+** invocation of a geometry function, and as the destructor for the geometry
+** functions themselves.
+*/
+static void doSqlite3Free(void *p){
+  sqlite3_free(p);
+}
+
+/*
+** Each call to sqlite3_rtree_geometry_callback() creates an ordinary SQLite
+** scalar user function. This C function is the callback used for all such
+** registered SQL functions.
+**
+** The scalar user functions return a blob that is interpreted by r-tree
+** table MATCH operators.
+*/
+static void geomCallback(sqlite3_context *ctx, int nArg, sqlite3_value **aArg){
+  RtreeGeomCallback *pGeomCtx = (RtreeGeomCallback *)sqlite3_user_data(ctx);
+  RtreeMatchArg *pBlob;
+  int nBlob;
+
+  nBlob = sizeof(RtreeMatchArg) + (nArg-1)*sizeof(double);
+  pBlob = (RtreeMatchArg *)sqlite3_malloc(nBlob);
+  if( !pBlob ){
+    sqlite3_result_error_nomem(ctx);
+  }else{
+    int i;
+    pBlob->magic = RTREE_GEOMETRY_MAGIC;
+    pBlob->xGeom = pGeomCtx->xGeom;
+    pBlob->pContext = pGeomCtx->pContext;
+    pBlob->nParam = nArg;
+    for(i=0; i<nArg; i++){
+      pBlob->aParam[i] = sqlite3_value_double(aArg[i]);
+    }
+    sqlite3_result_blob(ctx, pBlob, nBlob, doSqlite3Free);
+  }
+}
+
+/*
+** Register a new geometry function for use with the r-tree MATCH operator.
+*/
+SQLITE_API int sqlite3_rtree_geometry_callback(
+  sqlite3 *db,
+  const char *zGeom,
+  int (*xGeom)(sqlite3_rtree_geometry *, int, double *, int *),
+  void *pContext
+){
+  RtreeGeomCallback *pGeomCtx;      /* Context object for new user-function */
+
+  /* Allocate and populate the context object. */
+  pGeomCtx = (RtreeGeomCallback *)sqlite3_malloc(sizeof(RtreeGeomCallback));
+  if( !pGeomCtx ) return SQLITE_NOMEM;
+  pGeomCtx->xGeom = xGeom;
+  pGeomCtx->pContext = pContext;
+
+  /* Create the new user-function. Register a destructor function to delete
+  ** the context object when it is no longer required.  */
+  return sqlite3_create_function_v2(db, zGeom, -1, SQLITE_ANY, 
+      (void *)pGeomCtx, geomCallback, 0, 0, doSqlite3Free
+  );
+}
+
 #if !SQLITE_CORE
 SQLITE_API int sqlite3_extension_init(
   sqlite3 *db,
diff --git a/dist/sqlite3.h b/dist/sqlite3.h
index 7644be2..ba51372 100644
--- a/dist/sqlite3.h
+++ b/dist/sqlite3.h
@@ -97,7 +97,7 @@
 **
 ** Since version 3.6.18, SQLite source code has been stored in the
 ** <a href="http://www.fossil-scm.org/">Fossil configuration management
-** system</a>.  ^The SQLITE_SOURCE_ID macro evalutes to
+** system</a>.  ^The SQLITE_SOURCE_ID macro evaluates to
 ** a string which identifies a particular check-in of SQLite
 ** within its configuration management system.  ^The SQLITE_SOURCE_ID
 ** string contains the date and time of the check-in (UTC) and an SHA1
@@ -107,9 +107,9 @@
 ** [sqlite3_libversion_number()], [sqlite3_sourceid()],
 ** [sqlite_version()] and [sqlite_source_id()].
 */
-#define SQLITE_VERSION        "3.7.0"
-#define SQLITE_VERSION_NUMBER 3007000
-#define SQLITE_SOURCE_ID      "2010-07-07 14:45:41 8eefc287265443ec043bdab629597e79c9d22006"
+#define SQLITE_VERSION        "3.7.3"
+#define SQLITE_VERSION_NUMBER 3007003
+#define SQLITE_SOURCE_ID      "2010-09-28 07:24:50 88108fff672b6012ffe87ba4b1efe6d5a07037d1"
 
 /*
 ** CAPI3REF: Run-Time Library Version Numbers
@@ -154,7 +154,7 @@
 ** compile time.  ^The SQLITE_ prefix may be omitted from the 
 ** option name passed to sqlite3_compileoption_used().  
 **
-** ^The sqlite3_compileoption_get() function allows interating
+** ^The sqlite3_compileoption_get() function allows iterating
 ** over the list of options that were defined at compile time by
 ** returning the N-th compile time option string.  ^If N is out of range,
 ** sqlite3_compileoption_get() returns a NULL pointer.  ^The SQLITE_ 
@@ -162,7 +162,7 @@
 ** sqlite3_compileoption_get().
 **
 ** ^Support for the diagnostic functions sqlite3_compileoption_used()
-** and sqlite3_compileoption_get() may be omitted by specifing the 
+** and sqlite3_compileoption_get() may be omitted by specifying the 
 ** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
 **
 ** See also: SQL functions [sqlite_compileoption_used()] and
@@ -268,7 +268,7 @@
 **
 ** ^The sqlite3_close() routine is the destructor for the [sqlite3] object.
 ** ^Calls to sqlite3_close() return SQLITE_OK if the [sqlite3] object is
-** successfullly destroyed and all associated resources are deallocated.
+** successfully destroyed and all associated resources are deallocated.
 **
 ** Applications must [sqlite3_finalize | finalize] all [prepared statements]
 ** and [sqlite3_blob_close | close] all [BLOB handles] associated with
@@ -484,11 +484,12 @@
 #define SQLITE_OPEN_FULLMUTEX        0x00010000  /* Ok for sqlite3_open_v2() */
 #define SQLITE_OPEN_SHAREDCACHE      0x00020000  /* Ok for sqlite3_open_v2() */
 #define SQLITE_OPEN_PRIVATECACHE     0x00040000  /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_WAL              0x00080000  /* VFS only */
 
 /*
 ** CAPI3REF: Device Characteristics
 **
-** The xDeviceCapabilities method of the [sqlite3_io_methods]
+** The xDeviceCharacteristics method of the [sqlite3_io_methods]
 ** object returns an integer which is a vector of the these
 ** bit values expressing I/O characteristics of the mass storage
 ** device that holds the file that the [sqlite3_io_methods]
@@ -668,11 +669,10 @@
   int (*xSectorSize)(sqlite3_file*);
   int (*xDeviceCharacteristics)(sqlite3_file*);
   /* Methods above are valid for version 1 */
-  int (*xShmOpen)(sqlite3_file*);
+  int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
   int (*xShmLock)(sqlite3_file*, int offset, int n, int flags);
-  int (*xShmMap)(sqlite3_file*, int iPage, int pgsz, int, void volatile**);
   void (*xShmBarrier)(sqlite3_file*);
-  int (*xShmClose)(sqlite3_file*, int deleteFlag);
+  int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
   /* Methods above are valid for version 2 */
   /* Additional methods may be added in future releases */
 };
@@ -698,12 +698,21 @@
 ** is often close.  The underlying VFS might choose to preallocate database
 ** file space based on this hint in order to help writes to the database
 ** file run faster.
+**
+** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
+** extends and truncates the database file in chunks of a size specified
+** by the user. The fourth argument to [sqlite3_file_control()] should 
+** point to an integer (type int) containing the new chunk-size to use
+** for the nominated database. Allocating database file space in large
+** chunks (say 1MB at a time), may reduce file-system fragmentation and
+** improve performance on some systems.
 */
 #define SQLITE_FCNTL_LOCKSTATE        1
 #define SQLITE_GET_LOCKPROXYFILE      2
 #define SQLITE_SET_LOCKPROXYFILE      3
 #define SQLITE_LAST_ERRNO             4
 #define SQLITE_FCNTL_SIZE_HINT        5
+#define SQLITE_FCNTL_CHUNK_SIZE       6
 
 /*
 ** CAPI3REF: Mutex Handle
@@ -751,15 +760,19 @@
 ** The zName field holds the name of the VFS module.  The name must
 ** be unique across all VFS modules.
 **
-** SQLite will guarantee that the zFilename parameter to xOpen
+** ^SQLite guarantees that the zFilename parameter to xOpen
 ** is either a NULL pointer or string obtained
-** from xFullPathname().  SQLite further guarantees that
+** from xFullPathname() with an optional suffix added.
+** ^If a suffix is added to the zFilename parameter, it will
+** consist of a single "-" character followed by no more than
+** 10 alphanumeric and/or "-" characters.
+** ^SQLite further guarantees that
 ** the string will be valid and unchanged until xClose() is
 ** called. Because of the previous sentence,
 ** the [sqlite3_file] can safely store a pointer to the
 ** filename if it needs to remember the filename for some reason.
-** If the zFilename parameter is xOpen is a NULL pointer then xOpen
-** must invent its own temporary name for the file.  Whenever the 
+** If the zFilename parameter to xOpen is a NULL pointer then xOpen
+** must invent its own temporary name for the file.  ^Whenever the 
 ** xFilename parameter is NULL it will also be the case that the
 ** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
 **
@@ -770,7 +783,7 @@
 ** If xOpen() opens a file read-only then it sets *pOutFlags to
 ** include [SQLITE_OPEN_READONLY].  Other bits in *pOutFlags may be set.
 **
-** SQLite will also add one of the following flags to the xOpen()
+** ^(SQLite will also add one of the following flags to the xOpen()
 ** call, depending on the object being opened:
 **
 ** <ul>
@@ -781,7 +794,8 @@
 ** <li>  [SQLITE_OPEN_TRANSIENT_DB]
 ** <li>  [SQLITE_OPEN_SUBJOURNAL]
 ** <li>  [SQLITE_OPEN_MASTER_JOURNAL]
-** </ul>
+** <li>  [SQLITE_OPEN_WAL]
+** </ul>)^
 **
 ** The file I/O implementation can use the object type flags to
 ** change the way it deals with files.  For example, an application
@@ -800,10 +814,11 @@
 ** </ul>
 **
 ** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
-** deleted when it is closed.  The [SQLITE_OPEN_DELETEONCLOSE]
-** will be set for TEMP  databases, journals and for subjournals.
+** deleted when it is closed.  ^The [SQLITE_OPEN_DELETEONCLOSE]
+** will be set for TEMP databases and their journals, transient
+** databases, and subjournals.
 **
-** The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
+** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
 ** with the [SQLITE_OPEN_CREATE] flag, which are both directly
 ** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
 ** API.  The SQLITE_OPEN_EXCLUSIVE flag, when paired with the 
@@ -812,7 +827,7 @@
 ** It is <i>not</i> used to indicate the file should be opened 
 ** for exclusive access.
 **
-** At least szOsFile bytes of memory are allocated by SQLite
+** ^At least szOsFile bytes of memory are allocated by SQLite
 ** to hold the  [sqlite3_file] structure passed as the third
 ** argument to xOpen.  The xOpen method does not have to
 ** allocate the structure; it should just fill it in.  Note that
@@ -822,13 +837,13 @@
 ** element will be valid after xOpen returns regardless of the success
 ** or failure of the xOpen call.
 **
-** The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
+** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
 ** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
 ** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
 ** to test whether a file is at least readable.   The file can be a
 ** directory.
 **
-** SQLite will always allocate at least mxPathname+1 bytes for the
+** ^SQLite will always allocate at least mxPathname+1 bytes for the
 ** output buffer xFullPathname.  The exact size of the output buffer
 ** is also passed as a parameter to both  methods. If the output buffer
 ** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
@@ -842,10 +857,10 @@
 ** of good-quality randomness into zOut.  The return value is
 ** the actual number of bytes of randomness obtained.
 ** The xSleep() method causes the calling thread to sleep for at
-** least the number of microseconds given.  The xCurrentTime()
+** least the number of microseconds given.  ^The xCurrentTime()
 ** method returns a Julian Day Number for the current date and time as
 ** a floating point value.
-** The xCurrentTimeInt64() method returns, as an integer, the Julian
+** ^The xCurrentTimeInt64() method returns, as an integer, the Julian
 ** Day Number multipled by 86400000 (the number of milliseconds in 
 ** a 24-hour day).  
 ** ^SQLite will use the xCurrentTimeInt64() method to get the current
@@ -895,13 +910,20 @@
 ** With SQLITE_ACCESS_EXISTS, the xAccess method
 ** simply checks whether the file exists.
 ** With SQLITE_ACCESS_READWRITE, the xAccess method
-** checks whether the file is both readable and writable.
+** checks whether the named directory is both readable and writable
+** (in other words, if files can be added, removed, and renamed within
+** the directory).
+** The SQLITE_ACCESS_READWRITE constant is currently used only by the
+** [temp_store_directory pragma], though this could change in a future
+** release of SQLite.
 ** With SQLITE_ACCESS_READ, the xAccess method
-** checks whether the file is readable.
+** checks whether the file is readable.  The SQLITE_ACCESS_READ constant is
+** currently unused, though it might be used in a future release of
+** SQLite.
 */
 #define SQLITE_ACCESS_EXISTS    0
-#define SQLITE_ACCESS_READWRITE 1
-#define SQLITE_ACCESS_READ      2
+#define SQLITE_ACCESS_READWRITE 1   /* Used by PRAGMA temp_store_directory */
+#define SQLITE_ACCESS_READ      2   /* Unused */
 
 /*
 ** CAPI3REF: Flags for the xShmLock VFS method
@@ -1235,7 +1257,7 @@
 **   <ul>
 **   <li> [sqlite3_memory_used()]
 **   <li> [sqlite3_memory_highwater()]
-**   <li> [sqlite3_soft_heap_limit()]
+**   <li> [sqlite3_soft_heap_limit64()]
 **   <li> [sqlite3_status()]
 **   </ul>)^
 ** ^Memory allocation statistics are enabled by default unless SQLite is
@@ -1249,15 +1271,14 @@
 ** aligned memory buffer from which the scrach allocations will be
 ** drawn, the size of each scratch allocation (sz),
 ** and the maximum number of scratch allocations (N).  The sz
-** argument must be a multiple of 16. The sz parameter should be a few bytes
-** larger than the actual scratch space required due to internal overhead.
+** argument must be a multiple of 16.
 ** The first argument must be a pointer to an 8-byte aligned buffer
 ** of at least sz*N bytes of memory.
-** ^SQLite will use no more than one scratch buffer per thread.  So
-** N should be set to the expected maximum number of threads.  ^SQLite will
-** never require a scratch buffer that is more than 6 times the database
-** page size. ^If SQLite needs needs additional scratch memory beyond 
-** what is provided by this configuration option, then 
+** ^SQLite will use no more than two scratch buffers per thread.  So
+** N should be set to twice the expected maximum number of threads.
+** ^SQLite will never require a scratch buffer that is more than 6
+** times the database page size. ^If SQLite needs needs additional
+** scratch memory beyond what is provided by this configuration option, then 
 ** [sqlite3_malloc()] will be used to obtain the memory needed.</dd>
 **
 ** <dt>SQLITE_CONFIG_PAGECACHE</dt>
@@ -1277,8 +1298,7 @@
 ** memory needs for the first N pages that it adds to cache.  ^If additional
 ** page cache memory is needed beyond what is provided by this option, then
 ** SQLite goes to [sqlite3_malloc()] for the additional storage space.
-** ^The implementation might use one or more of the N buffers to hold 
-** memory accounting information. The pointer in the first argument must
+** The pointer in the first argument must
 ** be aligned to an 8-byte boundary or subsequent behavior of SQLite
 ** will be undefined.</dd>
 **
@@ -1407,8 +1427,14 @@
 ** or equal to the product of the second and third arguments.  The buffer
 ** must be aligned to an 8-byte boundary.  ^If the second argument to
 ** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally
-** rounded down to the next smaller
-** multiple of 8.  See also: [SQLITE_CONFIG_LOOKASIDE]</dd>
+** rounded down to the next smaller multiple of 8.  ^(The lookaside memory
+** configuration for a database connection can only be changed when that
+** connection is not currently using lookaside memory, or in other words
+** when the "current value" returned by
+** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero.
+** Any attempt to change the lookaside memory configuration when lookaside
+** memory is in use leaves the configuration unchanged and returns 
+** [SQLITE_BUSY].)^</dd>
 **
 ** </dl>
 */
@@ -1929,7 +1955,9 @@
 ** is not freed.
 **
 ** ^The memory returned by sqlite3_malloc() and sqlite3_realloc()
-** is always aligned to at least an 8 byte boundary.
+** is always aligned to at least an 8 byte boundary, or to a
+** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time
+** option is used.
 **
 ** In SQLite version 3.5.0 and 3.5.1, it was possible to define
 ** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
@@ -2172,7 +2200,13 @@
 ** ^The callback function registered by sqlite3_profile() is invoked
 ** as each SQL statement finishes.  ^The profile callback contains
 ** the original statement text and an estimate of wall-clock time
-** of how long that statement took to run.
+** of how long that statement took to run.  ^The profile callback
+** time is in units of nanoseconds, however the current implementation
+** is only capable of millisecond resolution so the six least significant
+** digits in the time are meaningless.  Future versions of SQLite
+** might provide greater resolution on the profiler callback.  The
+** sqlite3_profile() function is considered experimental and is
+** subject to change in future versions of SQLite.
 */
 SQLITE_API void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
 SQLITE_API SQLITE_EXPERIMENTAL void *sqlite3_profile(sqlite3*,
@@ -2181,17 +2215,28 @@
 /*
 ** CAPI3REF: Query Progress Callbacks
 **
-** ^This routine configures a callback function - the
-** progress callback - that is invoked periodically during long
-** running calls to [sqlite3_exec()], [sqlite3_step()] and
-** [sqlite3_get_table()].  An example use for this
+** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback
+** function X to be invoked periodically during long running calls to
+** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for
+** database connection D.  An example use for this
 ** interface is to keep a GUI updated during a large query.
 **
+** ^The parameter P is passed through as the only parameter to the 
+** callback function X.  ^The parameter N is the number of 
+** [virtual machine instructions] that are evaluated between successive
+** invocations of the callback X.
+**
+** ^Only a single progress handler may be defined at one time per
+** [database connection]; setting a new progress handler cancels the
+** old one.  ^Setting parameter X to NULL disables the progress handler.
+** ^The progress handler is also disabled by setting N to a value less
+** than 1.
+**
 ** ^If the progress callback returns non-zero, the operation is
 ** interrupted.  This feature can be used to implement a
 ** "Cancel" button on a GUI progress dialog box.
 **
-** The progress handler must not do anything that will modify
+** The progress handler callback must not do anything that will modify
 ** the database connection that invoked the progress handler.
 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
 ** database connections for the meaning of "modify" in this paragraph.
@@ -2250,7 +2295,7 @@
 ** If the 3rd parameter to sqlite3_open_v2() is not one of the
 ** combinations shown above or one of the combinations shown above combined
 ** with the [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX],
-** [SQLITE_OPEN_SHAREDCACHE] and/or [SQLITE_OPEN_SHAREDCACHE] flags,
+** [SQLITE_OPEN_SHAREDCACHE] and/or [SQLITE_OPEN_PRIVATECACHE] flags,
 ** then the behavior is undefined.
 **
 ** ^If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection
@@ -2375,17 +2420,22 @@
 ** [database connection] whose limit is to be set or queried.  The
 ** second parameter is one of the [limit categories] that define a
 ** class of constructs to be size limited.  The third parameter is the
-** new limit for that construct.  The function returns the old limit.)^
+** new limit for that construct.)^
 **
 ** ^If the new limit is a negative number, the limit is unchanged.
-** ^(For the limit category of SQLITE_LIMIT_XYZ there is a 
+** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a 
 ** [limits | hard upper bound]
-** set by a compile-time C preprocessor macro named 
-** [limits | SQLITE_MAX_XYZ].
+** set at compile-time by a C preprocessor macro called
+** [limits | SQLITE_MAX_<i>NAME</i>].
 ** (The "_LIMIT_" in the name is changed to "_MAX_".))^
 ** ^Attempts to increase a limit above its hard upper bound are
 ** silently truncated to the hard upper bound.
 **
+** ^Regardless of whether or not the limit was changed, the 
+** [sqlite3_limit()] interface returns the prior value of the limit.
+** ^Hence, to find the current value of a limit without changing it,
+** simply invoke this interface with the third parameter set to -1.
+**
 ** Run-time limits are intended for use in applications that manage
 ** both their own internal database and also databases that are controlled
 ** by untrusted external sources.  An example application might be a
@@ -2414,7 +2464,7 @@
 **
 ** <dl>
 ** ^(<dt>SQLITE_LIMIT_LENGTH</dt>
-** <dd>The maximum size of any string or BLOB or table row.<dd>)^
+** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^
 **
 ** ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt>
 ** <dd>The maximum length of an SQL statement, in bytes.</dd>)^
@@ -2432,7 +2482,9 @@
 **
 ** ^(<dt>SQLITE_LIMIT_VDBE_OP</dt>
 ** <dd>The maximum number of instructions in a virtual machine program
-** used to implement an SQL statement.</dd>)^
+** used to implement an SQL statement.  This limit is not currently
+** enforced, though that might be added in some future release of
+** SQLite.</dd>)^
 **
 ** ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
 ** <dd>The maximum number of arguments on a function.</dd>)^
@@ -2445,8 +2497,7 @@
 ** [GLOB] operators.</dd>)^
 **
 ** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
-** <dd>The maximum number of variables in an SQL statement that can
-** be bound.</dd>)^
+** <dd>The maximum index number of any [parameter] in an SQL statement.)^
 **
 ** ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
 ** <dd>The maximum depth of recursion for triggers.</dd>)^
@@ -2518,12 +2569,7 @@
 ** <li>
 ** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
 ** always used to do, [sqlite3_step()] will automatically recompile the SQL
-** statement and try to run it again.  ^If the schema has changed in
-** a way that makes the statement no longer valid, [sqlite3_step()] will still
-** return [SQLITE_SCHEMA].  But unlike the legacy behavior, [SQLITE_SCHEMA] is
-** now a fatal error.  Calling [sqlite3_prepare_v2()] again will not make the
-** error go away.  Note: use [sqlite3_errmsg()] to find the text
-** of the parsing error that results in an [SQLITE_SCHEMA] return.
+** statement and try to run it again.
 ** </li>
 **
 ** <li>
@@ -2536,11 +2582,16 @@
 ** </li>
 **
 ** <li>
-** ^If the value of a [parameter | host parameter] in the WHERE clause might
-** change the query plan for a statement, then the statement may be
-** automatically recompiled (as if there had been a schema change) on the first 
-** [sqlite3_step()] call following any change to the 
-** [sqlite3_bind_text | bindings] of the [parameter]. 
+** ^If the specific value bound to [parameter | host parameter] in the 
+** WHERE clause might influence the choice of query plan for a statement,
+** then the statement will be automatically recompiled, as if there had been 
+** a schema change, on the first  [sqlite3_step()] call following any change
+** to the [sqlite3_bind_text | bindings] of that [parameter]. 
+** ^The specific value of WHERE-clause [parameter] might influence the 
+** choice of query plan if the parameter is the left-hand side of a [LIKE]
+** or [GLOB] operator or if the parameter is compared to an indexed column
+** and the [SQLITE_ENABLE_STAT2] compile-time option is enabled.
+** the 
 ** </li>
 ** </ol>
 */
@@ -2607,7 +2658,7 @@
 ** then there is no distinction between protected and unprotected
 ** sqlite3_value objects and they can be used interchangeably.  However,
 ** for maximum code portability it is recommended that applications
-** still make the distinction between between protected and unprotected
+** still make the distinction between protected and unprotected
 ** sqlite3_value objects even when not strictly required.
 **
 ** ^The sqlite3_value objects that are passed as parameters into the
@@ -2653,7 +2704,7 @@
 ** </ul>
 **
 ** In the templates above, NNN represents an integer literal,
-** and VVV represents an alphanumeric identifer.)^  ^The values of these
+** and VVV represents an alphanumeric identifier.)^  ^The values of these
 ** parameters (also called "host parameter names" or "SQL parameters")
 ** can be set using the sqlite3_bind_*() routines defined here.
 **
@@ -2802,6 +2853,8 @@
 ** ^Return the number of columns in the result set returned by the
 ** [prepared statement]. ^This routine returns 0 if pStmt is an SQL
 ** statement that does not return data (for example an [UPDATE]).
+**
+** See also: [sqlite3_data_count()]
 */
 SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);
 
@@ -2992,8 +3045,14 @@
 /*
 ** CAPI3REF: Number of columns in a result set
 **
-** ^The sqlite3_data_count(P) the number of columns in the
-** of the result set of [prepared statement] P.
+** ^The sqlite3_data_count(P) interface returns the number of columns in the
+** current row of the result set of [prepared statement] P.
+** ^If prepared statement P does not have results ready to return
+** (via calls to the [sqlite3_column_int | sqlite3_column_*()] of
+** interfaces) then sqlite3_data_count(P) returns 0.
+** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.
+**
+** See also: [sqlite3_column_count()]
 */
 SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
 
@@ -3073,18 +3132,26 @@
 ** ^If the result is a numeric value then sqlite3_column_bytes() uses
 ** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
 ** the number of bytes in that string.
-** ^The value returned does not include the zero terminator at the end
-** of the string.  ^For clarity: the value returned is the number of
+** ^If the result is NULL, then sqlite3_column_bytes() returns zero.
+**
+** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16()
+** routine returns the number of bytes in that BLOB or string.
+** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts
+** the string to UTF-16 and then returns the number of bytes.
+** ^If the result is a numeric value then sqlite3_column_bytes16() uses
+** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns
+** the number of bytes in that string.
+** ^If the result is NULL, then sqlite3_column_bytes16() returns zero.
+**
+** ^The values returned by [sqlite3_column_bytes()] and 
+** [sqlite3_column_bytes16()] do not include the zero terminators at the end
+** of the string.  ^For clarity: the values returned by
+** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of
 ** bytes in the string, not the number of characters.
 **
 ** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
 ** even empty strings, are always zero terminated.  ^The return
-** value from sqlite3_column_blob() for a zero-length BLOB is an arbitrary
-** pointer, possibly even a NULL pointer.
-**
-** ^The sqlite3_column_bytes16() routine is similar to sqlite3_column_bytes()
-** but leaves the result in UTF-16 in native byte order instead of UTF-8.
-** ^The zero terminator is not included in this count.
+** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.
 **
 ** ^The object returned by [sqlite3_column_value()] is an
 ** [unprotected sqlite3_value] object.  An unprotected sqlite3_value object
@@ -3129,10 +3196,10 @@
 ** used in the table for brevity and because they are familiar to most
 ** C programmers.
 **
-** ^Note that when type conversions occur, pointers returned by prior
+** Note that when type conversions occur, pointers returned by prior
 ** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
 ** sqlite3_column_text16() may be invalidated.
-** ^(Type conversions and pointer invalidations might occur
+** Type conversions and pointer invalidations might occur
 ** in the following cases:
 **
 ** <ul>
@@ -3145,22 +3212,22 @@
 ** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
 **      sqlite3_column_text() is called.  The content must be converted
 **      to UTF-8.</li>
-** </ul>)^
+** </ul>
 **
 ** ^Conversions between UTF-16be and UTF-16le are always done in place and do
 ** not invalidate a prior pointer, though of course the content of the buffer
-** that the prior pointer points to will have been modified.  Other kinds
+** that the prior pointer references will have been modified.  Other kinds
 ** of conversion are done in place when it is possible, but sometimes they
 ** are not possible and in those cases prior pointers are invalidated.
 **
-** ^(The safest and easiest to remember policy is to invoke these routines
+** The safest and easiest to remember policy is to invoke these routines
 ** in one of the following ways:
 **
 ** <ul>
 **  <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
 **  <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
 **  <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
-** </ul>)^
+** </ul>
 **
 ** In other words, you should call sqlite3_column_text(),
 ** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
@@ -3244,23 +3311,25 @@
 ** KEYWORDS: {application-defined SQL function}
 ** KEYWORDS: {application-defined SQL functions}
 **
-** ^These two functions (collectively known as "function creation routines")
+** ^These functions (collectively known as "function creation routines")
 ** are used to add SQL functions or aggregates or to redefine the behavior
-** of existing SQL functions or aggregates.  The only difference between the
-** two is that the second parameter, the name of the (scalar) function or
-** aggregate, is encoded in UTF-8 for sqlite3_create_function() and UTF-16
-** for sqlite3_create_function16().
+** of existing SQL functions or aggregates.  The only differences between
+** these routines are the text encoding expected for
+** the the second parameter (the name of the function being created)
+** and the presence or absence of a destructor callback for
+** the application data pointer.
 **
 ** ^The first parameter is the [database connection] to which the SQL
 ** function is to be added.  ^If an application uses more than one database
 ** connection then application-defined SQL functions must be added
 ** to each database connection separately.
 **
-** The second parameter is the name of the SQL function to be created or
-** redefined.  ^The length of the name is limited to 255 bytes, exclusive of
-** the zero-terminator.  Note that the name length limit is in bytes, not
-** characters.  ^Any attempt to create a function with a longer name
-** will result in [SQLITE_ERROR] being returned.
+** ^The second parameter is the name of the SQL function to be created or
+** redefined.  ^The length of the name is limited to 255 bytes in a UTF-8
+** representation, exclusive of the zero-terminator.  ^Note that the name
+** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes.  
+** ^Any attempt to create a function with a longer name
+** will result in [SQLITE_MISUSE] being returned.
 **
 ** ^The third parameter (nArg)
 ** is the number of arguments that the SQL function or
@@ -3270,10 +3339,10 @@
 ** parameter is less than -1 or greater than 127 then the behavior is
 ** undefined.
 **
-** The fourth parameter, eTextRep, specifies what
+** ^The fourth parameter, eTextRep, specifies what
 ** [SQLITE_UTF8 | text encoding] this SQL function prefers for
-** its parameters.  Any SQL function implementation should be able to work
-** work with UTF-8, UTF-16le, or UTF-16be.  But some implementations may be
+** its parameters.  Every SQL function implementation must be able to work
+** with UTF-8, UTF-16le, or UTF-16be.  But some implementations may be
 ** more efficient with one encoding than another.  ^An application may
 ** invoke sqlite3_create_function() or sqlite3_create_function16() multiple
 ** times with the same function but with different values of eTextRep.
@@ -3285,13 +3354,21 @@
 ** ^(The fifth parameter is an arbitrary pointer.  The implementation of the
 ** function can gain access to this pointer using [sqlite3_user_data()].)^
 **
-** The seventh, eighth and ninth parameters, xFunc, xStep and xFinal, are
+** ^The seventh, eighth and ninth parameters, xFunc, xStep and xFinal, are
 ** pointers to C-language functions that implement the SQL function or
 ** aggregate. ^A scalar SQL function requires an implementation of the xFunc
-** callback only; NULL pointers should be passed as the xStep and xFinal
+** callback only; NULL pointers must be passed as the xStep and xFinal
 ** parameters. ^An aggregate SQL function requires an implementation of xStep
-** and xFinal and NULL should be passed for xFunc. ^To delete an existing
-** SQL function or aggregate, pass NULL for all three function callbacks.
+** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing
+** SQL function or aggregate, pass NULL poiners for all three function
+** callbacks.
+**
+** ^If the tenth parameter to sqlite3_create_function_v2() is not NULL,
+** then it is invoked when the function is deleted, either by being
+** overloaded or when the database connection closes.
+** ^When the destructure callback of the tenth parameter is invoked, it
+** is passed a single argument which is a copy of the pointer which was
+** the fifth parameter to sqlite3_create_function_v2().
 **
 ** ^It is permitted to register multiple implementations of the same
 ** functions with the same name but with either differing numbers of
@@ -3307,11 +3384,6 @@
 ** between UTF8 and UTF16.
 **
 ** ^Built-in functions may be overloaded by new application-defined functions.
-** ^The first application-defined function with a given name overrides all
-** built-in functions in the same [database connection] with the same name.
-** ^Subsequent application-defined functions of the same name only override 
-** prior application-defined functions that are an exact match for the
-** number of parameters and preferred encoding.
 **
 ** ^An application-defined function is permitted to call other
 ** SQLite interfaces.  However, such calls must not
@@ -3338,6 +3410,17 @@
   void (*xStep)(sqlite3_context*,int,sqlite3_value**),
   void (*xFinal)(sqlite3_context*)
 );
+SQLITE_API int sqlite3_create_function_v2(
+  sqlite3 *db,
+  const char *zFunctionName,
+  int nArg,
+  int eTextRep,
+  void *pApp,
+  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
+  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
+  void (*xFinal)(sqlite3_context*),
+  void(*xDestroy)(void*)
+);
 
 /*
 ** CAPI3REF: Text Encodings
@@ -3432,7 +3515,7 @@
 /*
 ** CAPI3REF: Obtain Aggregate Function Context
 **
-** Implementions of aggregate SQL functions use this
+** Implementations of aggregate SQL functions use this
 ** routine to allocate memory for storing their state.
 **
 ** ^The first time the sqlite3_aggregate_context(C,N) routine is called 
@@ -3684,46 +3767,70 @@
 /*
 ** CAPI3REF: Define New Collating Sequences
 **
-** These functions are used to add new collation sequences to the
-** [database connection] specified as the first argument.
+** ^These functions add, remove, or modify a [collation] associated
+** with the [database connection] specified as the first argument.
 **
-** ^The name of the new collation sequence is specified as a UTF-8 string
+** ^The name of the collation is a UTF-8 string
 ** for sqlite3_create_collation() and sqlite3_create_collation_v2()
-** and a UTF-16 string for sqlite3_create_collation16(). ^In all cases
-** the name is passed as the second function argument.
+** and a UTF-16 string in native byte order for sqlite3_create_collation16().
+** ^Collation names that compare equal according to [sqlite3_strnicmp()] are
+** considered to be the same name.
 **
-** ^The third argument may be one of the constants [SQLITE_UTF8],
-** [SQLITE_UTF16LE], or [SQLITE_UTF16BE], indicating that the user-supplied
-** routine expects to be passed pointers to strings encoded using UTF-8,
-** UTF-16 little-endian, or UTF-16 big-endian, respectively. ^The
-** third argument might also be [SQLITE_UTF16] to indicate that the routine
-** expects pointers to be UTF-16 strings in the native byte order, or the
-** argument can be [SQLITE_UTF16_ALIGNED] if the
-** the routine expects pointers to 16-bit word aligned strings
-** of UTF-16 in the native byte order.
+** ^(The third argument (eTextRep) must be one of the constants:
+** <ul>
+** <li> [SQLITE_UTF8],
+** <li> [SQLITE_UTF16LE],
+** <li> [SQLITE_UTF16BE],
+** <li> [SQLITE_UTF16], or
+** <li> [SQLITE_UTF16_ALIGNED].
+** </ul>)^
+** ^The eTextRep argument determines the encoding of strings passed
+** to the collating function callback, xCallback.
+** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep
+** force strings to be UTF16 with native byte order.
+** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin
+** on an even byte address.
 **
-** A pointer to the user supplied routine must be passed as the fifth
-** argument.  ^If it is NULL, this is the same as deleting the collation
-** sequence (so that SQLite cannot call it anymore).
-** ^Each time the application supplied function is invoked, it is passed
-** as its first parameter a copy of the void* passed as the fourth argument
-** to sqlite3_create_collation() or sqlite3_create_collation16().
+** ^The fourth argument, pArg, is a application data pointer that is passed
+** through as the first argument to the collating function callback.
 **
-** ^The remaining arguments to the application-supplied routine are two strings,
-** each represented by a (length, data) pair and encoded in the encoding
-** that was passed as the third argument when the collation sequence was
-** registered.  The application defined collation routine should
-** return negative, zero or positive if the first string is less than,
-** equal to, or greater than the second string. i.e. (STRING1 - STRING2).
+** ^The fifth argument, xCallback, is a pointer to the collating function.
+** ^Multiple collating functions can be registered using the same name but
+** with different eTextRep parameters and SQLite will use whichever
+** function requires the least amount of data transformation.
+** ^If the xCallback argument is NULL then the collating function is
+** deleted.  ^When all collating functions having the same name are deleted,
+** that collation is no longer usable.
+**
+** ^The collating function callback is invoked with a copy of the pArg 
+** application data pointer and with two strings in the encoding specified
+** by the eTextRep argument.  The collating function must return an
+** integer that is negative, zero, or positive
+** if the first string is less than, equal to, or greater than the second,
+** respectively.  A collating function must alway return the same answer
+** given the same inputs.  If two or more collating functions are registered
+** to the same collation name (using different eTextRep values) then all
+** must give an equivalent answer when invoked with equivalent strings.
+** The collating function must obey the following properties for all
+** strings A, B, and C:
+**
+** <ol>
+** <li> If A==B then B==A.
+** <li> If A==B and B==C then A==C.
+** <li> If A&lt;B THEN B&gt;A.
+** <li> If A&lt;B and B&lt;C then A&lt;C.
+** </ol>
+**
+** If a collating function fails any of the above constraints and that
+** collating function is  registered and used, then the behavior of SQLite
+** is undefined.
 **
 ** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()
-** except that it takes an extra argument which is a destructor for
-** the collation.  ^The destructor is called when the collation is
-** destroyed and is passed a copy of the fourth parameter void* pointer
-** of the sqlite3_create_collation_v2().
-** ^Collations are destroyed when they are overridden by later calls to the
-** collation creation functions or when the [database connection] is closed
-** using [sqlite3_close()].
+** with the addition that the xDestroy callback is invoked on pArg when
+** the collating function is deleted.
+** ^Collating functions are deleted when they are overridden by later
+** calls to the collation creation functions or when the
+** [database connection] is closed using [sqlite3_close()].
 **
 ** See also:  [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
 */
@@ -3731,14 +3838,14 @@
   sqlite3*, 
   const char *zName, 
   int eTextRep, 
-  void*,
+  void *pArg,
   int(*xCompare)(void*,int,const void*,int,const void*)
 );
 SQLITE_API int sqlite3_create_collation_v2(
   sqlite3*, 
   const char *zName, 
   int eTextRep, 
-  void*,
+  void *pArg,
   int(*xCompare)(void*,int,const void*,int,const void*),
   void(*xDestroy)(void*)
 );
@@ -3746,7 +3853,7 @@
   sqlite3*, 
   const void *zName,
   int eTextRep, 
-  void*,
+  void *pArg,
   int(*xCompare)(void*,int,const void*,int,const void*)
 );
 
@@ -3835,16 +3942,19 @@
 /*
 ** CAPI3REF: Suspend Execution For A Short Time
 **
-** ^The sqlite3_sleep() function causes the current thread to suspend execution
+** The sqlite3_sleep() function causes the current thread to suspend execution
 ** for at least a number of milliseconds specified in its parameter.
 **
-** ^If the operating system does not support sleep requests with
+** If the operating system does not support sleep requests with
 ** millisecond time resolution, then the time will be rounded up to
-** the nearest second. ^The number of milliseconds of sleep actually
+** the nearest second. The number of milliseconds of sleep actually
 ** requested from the operating system is returned.
 **
 ** ^SQLite implements this interface by calling the xSleep()
-** method of the default [sqlite3_vfs] object.
+** method of the default [sqlite3_vfs] object.  If the xSleep() method
+** of the default VFS is not implemented correctly, or not implemented at
+** all, then the behavior of sqlite3_sleep() may deviate from the description
+** in the previous paragraphs.
 */
 SQLITE_API int sqlite3_sleep(int);
 
@@ -4066,40 +4176,73 @@
 ** pages to improve performance is an example of non-essential memory.
 ** ^sqlite3_release_memory() returns the number of bytes actually freed,
 ** which might be more or less than the amount requested.
+** ^The sqlite3_release_memory() routine is a no-op returning zero
+** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT].
 */
 SQLITE_API int sqlite3_release_memory(int);
 
 /*
 ** CAPI3REF: Impose A Limit On Heap Size
 **
-** ^The sqlite3_soft_heap_limit() interface places a "soft" limit
-** on the amount of heap memory that may be allocated by SQLite.
-** ^If an internal allocation is requested that would exceed the
-** soft heap limit, [sqlite3_release_memory()] is invoked one or
-** more times to free up some space before the allocation is performed.
+** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the
+** soft limit on the amount of heap memory that may be allocated by SQLite.
+** ^SQLite strives to keep heap memory utilization below the soft heap
+** limit by reducing the number of pages held in the page cache
+** as heap memory usages approaches the limit.
+** ^The soft heap limit is "soft" because even though SQLite strives to stay
+** below the limit, it will exceed the limit rather than generate
+** an [SQLITE_NOMEM] error.  In other words, the soft heap limit 
+** is advisory only.
 **
-** ^The limit is called "soft" because if [sqlite3_release_memory()]
-** cannot free sufficient memory to prevent the limit from being exceeded,
-** the memory is allocated anyway and the current operation proceeds.
+** ^The return value from sqlite3_soft_heap_limit64() is the size of
+** the soft heap limit prior to the call.  ^If the argument N is negative
+** then no change is made to the soft heap limit.  Hence, the current
+** size of the soft heap limit can be determined by invoking
+** sqlite3_soft_heap_limit64() with a negative argument.
 **
-** ^A negative or zero value for N means that there is no soft heap limit and
-** [sqlite3_release_memory()] will only be called when memory is exhausted.
-** ^The default value for the soft heap limit is zero.
+** ^If the argument N is zero then the soft heap limit is disabled.
 **
-** ^(SQLite makes a best effort to honor the soft heap limit.
-** But if the soft heap limit cannot be honored, execution will
-** continue without error or notification.)^  This is why the limit is
-** called a "soft" limit.  It is advisory only.
+** ^(The soft heap limit is not enforced in the current implementation
+** if one or more of following conditions are true:
 **
-** Prior to SQLite version 3.5.0, this routine only constrained the memory
-** allocated by a single thread - the same thread in which this routine
-** runs.  Beginning with SQLite version 3.5.0, the soft heap limit is
-** applied to all threads. The value specified for the soft heap limit
-** is an upper bound on the total memory allocation for all threads. In
-** version 3.5.0 there is no mechanism for limiting the heap usage for
-** individual threads.
+** <ul>
+** <li> The soft heap limit is set to zero.
+** <li> Memory accounting is disabled using a combination of the
+**      [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and
+**      the [SQLITE_DEFAULT_MEMSTATUS] compile-time option.
+** <li> An alternative page cache implementation is specifed using
+**      [sqlite3_config]([SQLITE_CONFIG_PCACHE],...).
+** <li> The page cache allocates from its own memory pool supplied
+**      by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than
+**      from the heap.
+** </ul>)^
+**
+** Beginning with SQLite version 3.7.3, the soft heap limit is enforced
+** regardless of whether or not the [SQLITE_ENABLE_MEMORY_MANAGEMENT]
+** compile-time option is invoked.  With [SQLITE_ENABLE_MEMORY_MANAGEMENT],
+** the soft heap limit is enforced on every memory allocation.  Without
+** [SQLITE_ENABLE_MEMORY_MANAGEMENT], the soft heap limit is only enforced
+** when memory is allocated by the page cache.  Testing suggests that because
+** the page cache is the predominate memory user in SQLite, most
+** applications will achieve adequate soft heap limit enforcement without
+** the use of [SQLITE_ENABLE_MEMORY_MANAGEMENT].
+**
+** The circumstances under which SQLite will enforce the soft heap limit may
+** changes in future releases of SQLite.
 */
-SQLITE_API void sqlite3_soft_heap_limit(int);
+SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N);
+
+/*
+** CAPI3REF: Deprecated Soft Heap Limit Interface
+** DEPRECATED
+**
+** This is a deprecated version of the [sqlite3_soft_heap_limit64()]
+** interface.  This routine is provided for historical compatibility
+** only.  All new applications should use the
+** [sqlite3_soft_heap_limit64()] interface rather than this one.
+*/
+SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N);
+
 
 /*
 ** CAPI3REF: Extract Metadata About A Column Of A Table
@@ -4223,34 +4366,47 @@
 SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
 
 /*
-** CAPI3REF: Automatically Load An Extensions
+** CAPI3REF: Automatically Load Statically Linked Extensions
 **
-** ^This API can be invoked at program startup in order to register
-** one or more statically linked extensions that will be available
-** to all new [database connections].
+** ^This interface causes the xEntryPoint() function to be invoked for
+** each new [database connection] that is created.  The idea here is that
+** xEntryPoint() is the entry point for a statically linked SQLite extension
+** that is to be automatically loaded into all new database connections.
 **
-** ^(This routine stores a pointer to the extension entry point
-** in an array that is obtained from [sqlite3_malloc()].  That memory
-** is deallocated by [sqlite3_reset_auto_extension()].)^
+** ^(Even though the function prototype shows that xEntryPoint() takes
+** no arguments and returns void, SQLite invokes xEntryPoint() with three
+** arguments and expects and integer result as if the signature of the
+** entry point where as follows:
 **
-** ^This function registers an extension entry point that is
-** automatically invoked whenever a new [database connection]
-** is opened using [sqlite3_open()], [sqlite3_open16()],
-** or [sqlite3_open_v2()].
-** ^Duplicate extensions are detected so calling this routine
-** multiple times with the same extension is harmless.
-** ^Automatic extensions apply across all threads.
+** <blockquote><pre>
+** &nbsp;  int xEntryPoint(
+** &nbsp;    sqlite3 *db,
+** &nbsp;    const char **pzErrMsg,
+** &nbsp;    const struct sqlite3_api_routines *pThunk
+** &nbsp;  );
+** </pre></blockquote>)^
+**
+** If the xEntryPoint routine encounters an error, it should make *pzErrMsg
+** point to an appropriate error message (obtained from [sqlite3_mprintf()])
+** and return an appropriate [error code].  ^SQLite ensures that *pzErrMsg
+** is NULL before calling the xEntryPoint().  ^SQLite will invoke
+** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns.  ^If any
+** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()],
+** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail.
+**
+** ^Calling sqlite3_auto_extension(X) with an entry point X that is already
+** on the list of automatic extensions is a harmless no-op. ^No entry point
+** will be called more than once for each database connection that is opened.
+**
+** See also: [sqlite3_reset_auto_extension()].
 */
 SQLITE_API int sqlite3_auto_extension(void (*xEntryPoint)(void));
 
 /*
 ** CAPI3REF: Reset Automatic Extension Loading
 **
-** ^(This function disables all previously registered automatic
-** extensions. It undoes the effect of all prior
-** [sqlite3_auto_extension()] calls.)^
-**
-** ^This function disables automatic extensions in all threads.
+** ^This interface disables all automatic extensions previously
+** registered using [sqlite3_auto_extension()].
 */
 SQLITE_API void sqlite3_reset_auto_extension(void);
 
@@ -4321,7 +4477,8 @@
 ** CAPI3REF: Virtual Table Indexing Information
 ** KEYWORDS: sqlite3_index_info
 **
-** The sqlite3_index_info structure and its substructures is used to
+** The sqlite3_index_info structure and its substructures is used as part
+** of the [virtual table] interface to
 ** pass information into and receive the reply from the [xBestIndex]
 ** method of a [virtual table module].  The fields under **Inputs** are the
 ** inputs to xBestIndex and are read-only.  xBestIndex inserts its
@@ -4329,10 +4486,12 @@
 **
 ** ^(The aConstraint[] array records WHERE clause constraints of the form:
 **
-** <pre>column OP expr</pre>
+** <blockquote>column OP expr</blockquote>
 **
 ** where OP is =, &lt;, &lt;=, &gt;, or &gt;=.)^  ^(The particular operator is
-** stored in aConstraint[].op.)^  ^(The index of the column is stored in
+** stored in aConstraint[].op using one of the
+** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^
+** ^(The index of the column is stored in
 ** aConstraint[].iColumn.)^  ^(aConstraint[].usable is TRUE if the
 ** expr on the right-hand side can be evaluated (and thus the constraint
 ** is usable) and false if it cannot.)^
@@ -4392,6 +4551,15 @@
   int orderByConsumed;       /* True if output is already ordered */
   double estimatedCost;      /* Estimated cost of using this index */
 };
+
+/*
+** CAPI3REF: Virtual Table Constraint Operator Codes
+**
+** These macros defined the allowed values for the
+** [sqlite3_index_info].aConstraint[].op field.  Each value represents
+** an operator that is part of a constraint term in the wHERE clause of
+** a query that uses a [virtual table].
+*/
 #define SQLITE_INDEX_CONSTRAINT_EQ    2
 #define SQLITE_INDEX_CONSTRAINT_GT    4
 #define SQLITE_INDEX_CONSTRAINT_LE    8
@@ -4877,7 +5045,7 @@
 **
 ** ^The xMutexInit method defined by this structure is invoked as
 ** part of system initialization by the sqlite3_initialize() function.
-** ^The xMutexInit routine is calle by SQLite exactly once for each
+** ^The xMutexInit routine is called by SQLite exactly once for each
 ** effective call to [sqlite3_initialize()].
 **
 ** ^The xMutexEnd method defined by this structure is invoked as
@@ -4910,7 +5078,7 @@
 ** it is passed a NULL pointer).
 **
 ** The xMutexInit() method must be threadsafe.  ^It must be harmless to
-** invoke xMutexInit() mutiple times within the same process and without
+** invoke xMutexInit() multiple times within the same process and without
 ** intervening calls to xMutexEnd().  Second and subsequent calls to
 ** xMutexInit() must be no-ops.
 **
@@ -5074,13 +5242,14 @@
 #define SQLITE_TESTCTRL_OPTIMIZATIONS           15
 #define SQLITE_TESTCTRL_ISKEYWORD               16
 #define SQLITE_TESTCTRL_PGHDRSZ                 17
-#define SQLITE_TESTCTRL_LAST                    17
+#define SQLITE_TESTCTRL_SCRATCHMALLOC           18
+#define SQLITE_TESTCTRL_LAST                    18
 
 /*
 ** CAPI3REF: SQLite Runtime Status
 **
 ** ^This interface is used to retrieve runtime status information
-** about the preformance of SQLite, and optionally to reset various
+** about the performance of SQLite, and optionally to reset various
 ** highwater marks.  ^The first argument is an integer code for
 ** the specific parameter to measure.  ^(Recognized integer codes
 ** are of the form [SQLITE_STATUS_MEMORY_USED | SQLITE_STATUS_...].)^
@@ -5093,7 +5262,7 @@
 ** ^(Other parameters record only the highwater mark and not the current
 ** value.  For these latter parameters nothing is written into *pCurrent.)^
 **
-** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a
+** ^The sqlite3_status() routine returns SQLITE_OK on success and a
 ** non-zero [error code] on failure.
 **
 ** This routine is threadsafe but is not atomic.  This routine can be
@@ -5132,6 +5301,9 @@
 ** *pHighwater parameter to [sqlite3_status()] is of interest.  
 ** The value written into the *pCurrent parameter is undefined.</dd>)^
 **
+** ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt>
+** <dd>This parameter records the number of separate memory allocations.</dd>)^
+**
 ** ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt>
 ** <dd>This parameter returns the number of pages used out of the
 ** [pagecache memory allocator] that was configured using 
@@ -5140,7 +5312,7 @@
 **
 ** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
 ** <dd>This parameter returns the number of bytes of page cache
-** allocation which could not be statisfied by the [SQLITE_CONFIG_PAGECACHE]
+** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE]
 ** buffer and where forced to overflow to [sqlite3_malloc()].  The
 ** returned value includes allocations that overflowed because they
 ** where too large (they were larger than the "sz" parameter to
@@ -5163,7 +5335,7 @@
 **
 ** ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
 ** <dd>This parameter returns the number of bytes of scratch memory
-** allocation which could not be statisfied by the [SQLITE_CONFIG_SCRATCH]
+** allocation which could not be satisfied by the [SQLITE_CONFIG_SCRATCH]
 ** buffer and where forced to overflow to [sqlite3_malloc()].  The values
 ** returned include overflows because the requested allocation was too
 ** larger (that is, because the requested allocation was larger than the
@@ -5193,6 +5365,7 @@
 #define SQLITE_STATUS_PARSER_STACK         6
 #define SQLITE_STATUS_PAGECACHE_SIZE       7
 #define SQLITE_STATUS_SCRATCH_SIZE         8
+#define SQLITE_STATUS_MALLOC_COUNT         9
 
 /*
 ** CAPI3REF: Database Connection Status
@@ -5202,7 +5375,7 @@
 ** database connection object to be interrogated.  ^The second argument
 ** is an integer constant, taken from the set of
 ** [SQLITE_DBSTATUS_LOOKASIDE_USED | SQLITE_DBSTATUS_*] macros, that
-** determiness the parameter to interrogate.  The set of 
+** determines the parameter to interrogate.  The set of 
 ** [SQLITE_DBSTATUS_LOOKASIDE_USED | SQLITE_DBSTATUS_*] macros is likely
 ** to grow in future releases of SQLite.
 **
@@ -5211,6 +5384,9 @@
 ** the resetFlg is true, then the highest instantaneous value is
 ** reset back down to the current value.
 **
+** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a
+** non-zero [error code] on failure.
+**
 ** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
 */
 SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
@@ -5232,16 +5408,33 @@
 ** <dd>This parameter returns the number of lookaside memory slots currently
 ** checked out.</dd>)^
 **
-** <dt>SQLITE_DBSTATUS_CACHE_USED</dt>
-** <dd>^This parameter returns the approximate number of of bytes of heap
-** memory used by all pager caches associated with the database connection.
+** ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt>
+** <dd>This parameter returns the approximate number of of bytes of heap
+** memory used by all pager caches associated with the database connection.)^
 ** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0.
-** checked out.</dd>)^
+**
+** ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt>
+** <dd>This parameter returns the approximate number of of bytes of heap
+** memory used to store the schema for all databases associated
+** with the connection - main, temp, and any [ATTACH]-ed databases.)^ 
+** ^The full amount of memory used by the schemas is reported, even if the
+** schema memory is shared with other database connections due to
+** [shared cache mode] being enabled.
+** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0.
+**
+** ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt>
+** <dd>This parameter returns the approximate number of of bytes of heap
+** and lookaside memory used by all prepared statements associated with
+** the database connection.)^
+** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0.
+** </dd>
 ** </dl>
 */
 #define SQLITE_DBSTATUS_LOOKASIDE_USED     0
 #define SQLITE_DBSTATUS_CACHE_USED         1
-#define SQLITE_DBSTATUS_MAX                1   /* Largest defined DBSTATUS */
+#define SQLITE_DBSTATUS_SCHEMA_USED        2
+#define SQLITE_DBSTATUS_STMT_USED          3
+#define SQLITE_DBSTATUS_MAX                3   /* Largest defined DBSTATUS */
 
 
 /*
@@ -5320,32 +5513,42 @@
 **
 ** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE], ...) interface can
 ** register an alternative page cache implementation by passing in an 
-** instance of the sqlite3_pcache_methods structure.)^ The majority of the 
-** heap memory used by SQLite is used by the page cache to cache data read 
-** from, or ready to be written to, the database file. By implementing a 
-** custom page cache using this API, an application can control more 
-** precisely the amount of memory consumed by SQLite, the way in which 
+** instance of the sqlite3_pcache_methods structure.)^
+** In many applications, most of the heap memory allocated by 
+** SQLite is used for the page cache.
+** By implementing a 
+** custom page cache using this API, an application can better control
+** the amount of memory consumed by SQLite, the way in which 
 ** that memory is allocated and released, and the policies used to 
 ** determine exactly which parts of a database file are cached and for 
 ** how long.
 **
+** The alternative page cache mechanism is an
+** extreme measure that is only needed by the most demanding applications.
+** The built-in page cache is recommended for most uses.
+**
 ** ^(The contents of the sqlite3_pcache_methods structure are copied to an
 ** internal buffer by SQLite within the call to [sqlite3_config].  Hence
 ** the application may discard the parameter after the call to
 ** [sqlite3_config()] returns.)^
 **
-** ^The xInit() method is called once for each call to [sqlite3_initialize()]
+** ^(The xInit() method is called once for each effective 
+** call to [sqlite3_initialize()])^
 ** (usually only once during the lifetime of the process). ^(The xInit()
 ** method is passed a copy of the sqlite3_pcache_methods.pArg value.)^
-** ^The xInit() method can set up up global structures and/or any mutexes
+** The intent of the xInit() method is to set up global data structures 
 ** required by the custom page cache implementation. 
+** ^(If the xInit() method is NULL, then the 
+** built-in default page cache is used instead of the application defined
+** page cache.)^
 **
-** ^The xShutdown() method is called from within [sqlite3_shutdown()], 
-** if the application invokes this API. It can be used to clean up 
+** ^The xShutdown() method is called by [sqlite3_shutdown()].
+** It can be used to clean up 
 ** any outstanding resources before process shutdown, if required.
+** ^The xShutdown() method may be NULL.
 **
-** ^SQLite holds a [SQLITE_MUTEX_RECURSIVE] mutex when it invokes
-** the xInit method, so the xInit method need not be threadsafe.  ^The
+** ^SQLite automatically serializes calls to the xInit method,
+** so the xInit method need not be threadsafe.  ^The
 ** xShutdown method is only called from [sqlite3_shutdown()] so it does
 ** not need to be threadsafe either.  All other methods must be threadsafe
 ** in multithreaded applications.
@@ -5353,47 +5556,50 @@
 ** ^SQLite will never invoke xInit() more than once without an intervening
 ** call to xShutdown().
 **
-** ^The xCreate() method is used to construct a new cache instance.  SQLite
-** will typically create one cache instance for each open database file,
+** ^SQLite invokes the xCreate() method to construct a new cache instance.
+** SQLite will typically create one cache instance for each open database file,
 ** though this is not guaranteed. ^The
 ** first parameter, szPage, is the size in bytes of the pages that must
 ** be allocated by the cache.  ^szPage will not be a power of two.  ^szPage
 ** will the page size of the database file that is to be cached plus an
-** increment (here called "R") of about 100 or 200.  ^SQLite will use the
+** increment (here called "R") of about 100 or 200.  SQLite will use the
 ** extra R bytes on each page to store metadata about the underlying
 ** database page on disk.  The value of R depends
 ** on the SQLite version, the target platform, and how SQLite was compiled.
 ** ^R is constant for a particular build of SQLite.  ^The second argument to
 ** xCreate(), bPurgeable, is true if the cache being created will
 ** be used to cache database pages of a file stored on disk, or
-** false if it is used for an in-memory database. ^The cache implementation
+** false if it is used for an in-memory database. The cache implementation
 ** does not have to do anything special based with the value of bPurgeable;
 ** it is purely advisory.  ^On a cache where bPurgeable is false, SQLite will
 ** never invoke xUnpin() except to deliberately delete a page.
-** ^In other words, a cache created with bPurgeable set to false will
+** ^In other words, calls to xUnpin() on a cache with bPurgeable set to
+** false will always have the "discard" flag set to true.  
+** ^Hence, a cache created with bPurgeable false will
 ** never contain any unpinned pages.
 **
 ** ^(The xCachesize() method may be called at any time by SQLite to set the
 ** suggested maximum cache-size (number of pages stored by) the cache
 ** instance passed as the first argument. This is the value configured using
-** the SQLite "[PRAGMA cache_size]" command.)^  ^As with the bPurgeable
+** the SQLite "[PRAGMA cache_size]" command.)^  As with the bPurgeable
 ** parameter, the implementation is not required to do anything with this
 ** value; it is advisory only.
 **
-** ^The xPagecount() method should return the number of pages currently
-** stored in the cache.
+** The xPagecount() method must return the number of pages currently
+** stored in the cache, both pinned and unpinned.
 ** 
-** ^The xFetch() method is used to fetch a page and return a pointer to it. 
-** ^A 'page', in this context, is a buffer of szPage bytes aligned at an
-** 8-byte boundary. ^The page to be fetched is determined by the key. ^The
-** mimimum key value is 1. After it has been retrieved using xFetch, the page 
+** The xFetch() method locates a page in the cache and returns a pointer to 
+** the page, or a NULL pointer.
+** A "page", in this context, means a buffer of szPage bytes aligned at an
+** 8-byte boundary. The page to be fetched is determined by the key. ^The
+** mimimum key value is 1.  After it has been retrieved using xFetch, the page 
 ** is considered to be "pinned".
 **
-** ^If the requested page is already in the page cache, then the page cache
+** If the requested page is already in the page cache, then the page cache
 ** implementation must return a pointer to the page buffer with its content
-** intact.  ^(If the requested page is not already in the cache, then the
-** behavior of the cache implementation is determined by the value of the
-** createFlag parameter passed to xFetch, according to the following table:
+** intact.  If the requested page is not already in the cache, then the
+** behavior of the cache implementation should use the value of the createFlag
+** parameter to help it determined what action to take:
 **
 ** <table border=1 width=85% align=center>
 ** <tr><th> createFlag <th> Behaviour when page is not already in cache
@@ -5402,36 +5608,35 @@
 **                 Otherwise return NULL.
 ** <tr><td> 2 <td> Make every effort to allocate a new page.  Only return
 **                 NULL if allocating a new page is effectively impossible.
-** </table>)^
+** </table>
 **
-** SQLite will normally invoke xFetch() with a createFlag of 0 or 1.  If
-** a call to xFetch() with createFlag==1 returns NULL, then SQLite will
+** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1.  SQLite
+** will only use a createFlag of 2 after a prior call with a createFlag of 1
+** failed.)^  In between the to xFetch() calls, SQLite may
 ** attempt to unpin one or more cache pages by spilling the content of
-** pinned pages to disk and synching the operating system disk cache. After
-** attempting to unpin pages, the xFetch() method will be invoked again with
-** a createFlag of 2.
+** pinned pages to disk and synching the operating system disk cache.
 **
 ** ^xUnpin() is called by SQLite with a pointer to a currently pinned page
-** as its second argument. ^(If the third parameter, discard, is non-zero,
-** then the page should be evicted from the cache. In this case SQLite 
-** assumes that the next time the page is retrieved from the cache using
-** the xFetch() method, it will be zeroed.)^ ^If the discard parameter is
-** zero, then the page is considered to be unpinned. ^The cache implementation
+** as its second argument.  If the third parameter, discard, is non-zero,
+** then the page must be evicted from the cache.
+** ^If the discard parameter is
+** zero, then the page may be discarded or retained at the discretion of
+** page cache implementation. ^The page cache implementation
 ** may choose to evict unpinned pages at any time.
 **
-** ^(The cache is not required to perform any reference counting. A single 
+** The cache must not perform any reference counting. A single 
 ** call to xUnpin() unpins the page regardless of the number of prior calls 
-** to xFetch().)^
+** to xFetch().
 **
-** ^The xRekey() method is used to change the key value associated with the
-** page passed as the second argument from oldKey to newKey. ^If the cache
-** previously contains an entry associated with newKey, it should be
+** The xRekey() method is used to change the key value associated with the
+** page passed as the second argument. If the cache
+** previously contains an entry associated with newKey, it must be
 ** discarded. ^Any prior cache entry associated with newKey is guaranteed not
 ** to be pinned.
 **
-** ^When SQLite calls the xTruncate() method, the cache must discard all
+** When SQLite calls the xTruncate() method, the cache must discard all
 ** existing cache entries with page numbers (keys) greater than or equal
-** to the value of the iLimit parameter passed to xTruncate(). ^If any
+** to the value of the iLimit parameter passed to xTruncate(). If any
 ** of these pages are pinned, they are implicitly unpinned, meaning that
 ** they can be safely discarded.
 **
@@ -5607,7 +5812,7 @@
 **
 ** ^Each call to sqlite3_backup_step() sets two values inside
 ** the [sqlite3_backup] object: the number of pages still to be backed
-** up and the total number of pages in the source databae file.
+** up and the total number of pages in the source database file.
 ** The sqlite3_backup_remaining() and sqlite3_backup_pagecount() interfaces
 ** retrieve these two values, respectively.
 **
@@ -5703,7 +5908,7 @@
 ** blocked connection already has a registered unlock-notify callback,
 ** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is
 ** called with a NULL pointer as its second argument, then any existing
-** unlock-notify callback is cancelled. ^The blocked connections 
+** unlock-notify callback is canceled. ^The blocked connections 
 ** unlock-notify callback may also be canceled by closing the blocked
 ** connection using [sqlite3_close()].
 **
@@ -5785,7 +5990,7 @@
 **
 ** ^The [sqlite3_strnicmp()] API allows applications and extensions to
 ** compare the contents of two buffers containing UTF-8 strings in a
-** case-indendent fashion, using the same definition of case independence 
+** case-independent fashion, using the same definition of case independence 
 ** that SQLite uses internally when comparing identifiers.
 */
 SQLITE_API int sqlite3_strnicmp(const char *, const char *, int);
@@ -5909,3 +6114,59 @@
 #endif
 #endif
 
+/*
+** 2010 August 30
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+*/
+
+#ifndef _SQLITE3RTREE_H_
+#define _SQLITE3RTREE_H_
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry;
+
+/*
+** Register a geometry callback named zGeom that can be used as part of an
+** R-Tree geometry query as follows:
+**
+**   SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zGeom(... params ...)
+*/
+SQLITE_API int sqlite3_rtree_geometry_callback(
+  sqlite3 *db,
+  const char *zGeom,
+  int (*xGeom)(sqlite3_rtree_geometry *, int nCoord, double *aCoord, int *pRes),
+  void *pContext
+);
+
+
+/*
+** A pointer to a structure of the following type is passed as the first
+** argument to callbacks registered using rtree_geometry_callback().
+*/
+struct sqlite3_rtree_geometry {
+  void *pContext;                 /* Copy of pContext passed to s_r_g_c() */
+  int nParam;                     /* Size of array aParam[] */
+  double *aParam;                 /* Parameters passed to SQL geom function */
+  void *pUser;                    /* Callback implementation user data */
+  void (*xDelUser)(void *);       /* Called by SQLite to clean up pUser */
+};
+
+
+#ifdef __cplusplus
+}  /* end of the 'extern "C"' block */
+#endif
+
+#endif  /* ifndef _SQLITE3RTREE_H_ */
+
diff --git a/dist/sqlite3.h.orig b/dist/sqlite3.h.orig
new file mode 100644
index 0000000..9edccf0
--- /dev/null
+++ b/dist/sqlite3.h.orig
@@ -0,0 +1,6169 @@
+/*
+** 2001 September 15
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This header file defines the interface that the SQLite library
+** presents to client programs.  If a C-function, structure, datatype,
+** or constant definition does not appear in this file, then it is
+** not a published API of SQLite, is subject to change without
+** notice, and should not be referenced by programs that use SQLite.
+**
+** Some of the definitions that are in this file are marked as
+** "experimental".  Experimental interfaces are normally new
+** features recently added to SQLite.  We do not anticipate changes
+** to experimental interfaces but reserve the right to make minor changes
+** if experience from use "in the wild" suggest such changes are prudent.
+**
+** The official C-language API documentation for SQLite is derived
+** from comments in this file.  This file is the authoritative source
+** on how SQLite interfaces are suppose to operate.
+**
+** The name of this file under configuration management is "sqlite.h.in".
+** The makefile makes some minor changes to this file (such as inserting
+** the version number) and changes its name to "sqlite3.h" as
+** part of the build process.
+*/
+#ifndef _SQLITE3_H_
+#define _SQLITE3_H_
+#include <stdarg.h>     /* Needed for the definition of va_list */
+
+/*
+** Make sure we can call this stuff from C++.
+*/
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+/*
+** Add the ability to override 'extern'
+*/
+#ifndef SQLITE_EXTERN
+# define SQLITE_EXTERN extern
+#endif
+
+#ifndef SQLITE_API
+# define SQLITE_API
+#endif
+
+
+/*
+** These no-op macros are used in front of interfaces to mark those
+** interfaces as either deprecated or experimental.  New applications
+** should not use deprecated interfaces - they are support for backwards
+** compatibility only.  Application writers should be aware that
+** experimental interfaces are subject to change in point releases.
+**
+** These macros used to resolve to various kinds of compiler magic that
+** would generate warning messages when they were used.  But that
+** compiler magic ended up generating such a flurry of bug reports
+** that we have taken it all out and gone back to using simple
+** noop macros.
+*/
+#define SQLITE_DEPRECATED
+#define SQLITE_EXPERIMENTAL
+
+/*
+** Ensure these symbols were not defined by some previous header file.
+*/
+#ifdef SQLITE_VERSION
+# undef SQLITE_VERSION
+#endif
+#ifdef SQLITE_VERSION_NUMBER
+# undef SQLITE_VERSION_NUMBER
+#endif
+
+/*
+** CAPI3REF: Compile-Time Library Version Numbers
+**
+** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header
+** evaluates to a string literal that is the SQLite version in the
+** format "X.Y.Z" where X is the major version number (always 3 for
+** SQLite3) and Y is the minor version number and Z is the release number.)^
+** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer
+** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same
+** numbers used in [SQLITE_VERSION].)^
+** The SQLITE_VERSION_NUMBER for any given release of SQLite will also
+** be larger than the release from which it is derived.  Either Y will
+** be held constant and Z will be incremented or else Y will be incremented
+** and Z will be reset to zero.
+**
+** Since version 3.6.18, SQLite source code has been stored in the
+** <a href="http://www.fossil-scm.org/">Fossil configuration management
+** system</a>.  ^The SQLITE_SOURCE_ID macro evaluates to
+** a string which identifies a particular check-in of SQLite
+** within its configuration management system.  ^The SQLITE_SOURCE_ID
+** string contains the date and time of the check-in (UTC) and an SHA1
+** hash of the entire source tree.
+**
+** See also: [sqlite3_libversion()],
+** [sqlite3_libversion_number()], [sqlite3_sourceid()],
+** [sqlite_version()] and [sqlite_source_id()].
+*/
+#define SQLITE_VERSION        "3.7.3"
+#define SQLITE_VERSION_NUMBER 3007003
+#define SQLITE_SOURCE_ID      "2010-09-28 07:24:50 88108fff672b6012ffe87ba4b1efe6d5a07037d1"
+
+/*
+** CAPI3REF: Run-Time Library Version Numbers
+** KEYWORDS: sqlite3_version, sqlite3_sourceid
+**
+** These interfaces provide the same information as the [SQLITE_VERSION],
+** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros
+** but are associated with the library instead of the header file.  ^(Cautious
+** programmers might include assert() statements in their application to
+** verify that values returned by these interfaces match the macros in
+** the header, and thus insure that the application is
+** compiled with matching library and header files.
+**
+** <blockquote><pre>
+** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
+** assert( strcmp(sqlite3_sourceid(),SQLITE_SOURCE_ID)==0 );
+** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
+** </pre></blockquote>)^
+**
+** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION]
+** macro.  ^The sqlite3_libversion() function returns a pointer to the
+** to the sqlite3_version[] string constant.  The sqlite3_libversion()
+** function is provided for use in DLLs since DLL users usually do not have
+** direct access to string constants within the DLL.  ^The
+** sqlite3_libversion_number() function returns an integer equal to
+** [SQLITE_VERSION_NUMBER].  ^The sqlite3_sourceid() function returns 
+** a pointer to a string constant whose value is the same as the 
+** [SQLITE_SOURCE_ID] C preprocessor macro.
+**
+** See also: [sqlite_version()] and [sqlite_source_id()].
+*/
+SQLITE_API SQLITE_EXTERN const char sqlite3_version[];
+SQLITE_API const char *sqlite3_libversion(void);
+SQLITE_API const char *sqlite3_sourceid(void);
+SQLITE_API int sqlite3_libversion_number(void);
+
+/*
+** CAPI3REF: Run-Time Library Compilation Options Diagnostics
+**
+** ^The sqlite3_compileoption_used() function returns 0 or 1 
+** indicating whether the specified option was defined at 
+** compile time.  ^The SQLITE_ prefix may be omitted from the 
+** option name passed to sqlite3_compileoption_used().  
+**
+** ^The sqlite3_compileoption_get() function allows iterating
+** over the list of options that were defined at compile time by
+** returning the N-th compile time option string.  ^If N is out of range,
+** sqlite3_compileoption_get() returns a NULL pointer.  ^The SQLITE_ 
+** prefix is omitted from any strings returned by 
+** sqlite3_compileoption_get().
+**
+** ^Support for the diagnostic functions sqlite3_compileoption_used()
+** and sqlite3_compileoption_get() may be omitted by specifying the 
+** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
+**
+** See also: SQL functions [sqlite_compileoption_used()] and
+** [sqlite_compileoption_get()] and the [compile_options pragma].
+*/
+#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
+SQLITE_API int sqlite3_compileoption_used(const char *zOptName);
+SQLITE_API const char *sqlite3_compileoption_get(int N);
+#endif
+
+/*
+** CAPI3REF: Test To See If The Library Is Threadsafe
+**
+** ^The sqlite3_threadsafe() function returns zero if and only if
+** SQLite was compiled mutexing code omitted due to the
+** [SQLITE_THREADSAFE] compile-time option being set to 0.
+**
+** SQLite can be compiled with or without mutexes.  When
+** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
+** are enabled and SQLite is threadsafe.  When the
+** [SQLITE_THREADSAFE] macro is 0, 
+** the mutexes are omitted.  Without the mutexes, it is not safe
+** to use SQLite concurrently from more than one thread.
+**
+** Enabling mutexes incurs a measurable performance penalty.
+** So if speed is of utmost importance, it makes sense to disable
+** the mutexes.  But for maximum safety, mutexes should be enabled.
+** ^The default behavior is for mutexes to be enabled.
+**
+** This interface can be used by an application to make sure that the
+** version of SQLite that it is linking against was compiled with
+** the desired setting of the [SQLITE_THREADSAFE] macro.
+**
+** This interface only reports on the compile-time mutex setting
+** of the [SQLITE_THREADSAFE] flag.  If SQLite is compiled with
+** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but
+** can be fully or partially disabled using a call to [sqlite3_config()]
+** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
+** or [SQLITE_CONFIG_MUTEX].  ^(The return value of the
+** sqlite3_threadsafe() function shows only the compile-time setting of
+** thread safety, not any run-time changes to that setting made by
+** sqlite3_config(). In other words, the return value from sqlite3_threadsafe()
+** is unchanged by calls to sqlite3_config().)^
+**
+** See the [threading mode] documentation for additional information.
+*/
+SQLITE_API int sqlite3_threadsafe(void);
+
+/*
+** CAPI3REF: Database Connection Handle
+** KEYWORDS: {database connection} {database connections}
+**
+** Each open SQLite database is represented by a pointer to an instance of
+** the opaque structure named "sqlite3".  It is useful to think of an sqlite3
+** pointer as an object.  The [sqlite3_open()], [sqlite3_open16()], and
+** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
+** is its destructor.  There are many other interfaces (such as
+** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
+** [sqlite3_busy_timeout()] to name but three) that are methods on an
+** sqlite3 object.
+*/
+typedef struct sqlite3 sqlite3;
+
+/*
+** CAPI3REF: 64-Bit Integer Types
+** KEYWORDS: sqlite_int64 sqlite_uint64
+**
+** Because there is no cross-platform way to specify 64-bit integer types
+** SQLite includes typedefs for 64-bit signed and unsigned integers.
+**
+** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
+** The sqlite_int64 and sqlite_uint64 types are supported for backwards
+** compatibility only.
+**
+** ^The sqlite3_int64 and sqlite_int64 types can store integer values
+** between -9223372036854775808 and +9223372036854775807 inclusive.  ^The
+** sqlite3_uint64 and sqlite_uint64 types can store integer values 
+** between 0 and +18446744073709551615 inclusive.
+*/
+#ifdef SQLITE_INT64_TYPE
+  typedef SQLITE_INT64_TYPE sqlite_int64;
+  typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
+#elif defined(_MSC_VER) || defined(__BORLANDC__)
+  typedef __int64 sqlite_int64;
+  typedef unsigned __int64 sqlite_uint64;
+#else
+  typedef long long int sqlite_int64;
+  typedef unsigned long long int sqlite_uint64;
+#endif
+typedef sqlite_int64 sqlite3_int64;
+typedef sqlite_uint64 sqlite3_uint64;
+
+/*
+** If compiling for a processor that lacks floating point support,
+** substitute integer for floating-point.
+*/
+#ifdef SQLITE_OMIT_FLOATING_POINT
+# define double sqlite3_int64
+#endif
+
+/*
+** CAPI3REF: Closing A Database Connection
+**
+** ^The sqlite3_close() routine is the destructor for the [sqlite3] object.
+** ^Calls to sqlite3_close() return SQLITE_OK if the [sqlite3] object is
+** successfully destroyed and all associated resources are deallocated.
+**
+** Applications must [sqlite3_finalize | finalize] all [prepared statements]
+** and [sqlite3_blob_close | close] all [BLOB handles] associated with
+** the [sqlite3] object prior to attempting to close the object.  ^If
+** sqlite3_close() is called on a [database connection] that still has
+** outstanding [prepared statements] or [BLOB handles], then it returns
+** SQLITE_BUSY.
+**
+** ^If [sqlite3_close()] is invoked while a transaction is open,
+** the transaction is automatically rolled back.
+**
+** The C parameter to [sqlite3_close(C)] must be either a NULL
+** pointer or an [sqlite3] object pointer obtained
+** from [sqlite3_open()], [sqlite3_open16()], or
+** [sqlite3_open_v2()], and not previously closed.
+** ^Calling sqlite3_close() with a NULL pointer argument is a 
+** harmless no-op.
+*/
+SQLITE_API int sqlite3_close(sqlite3 *);
+
+/*
+** The type for a callback function.
+** This is legacy and deprecated.  It is included for historical
+** compatibility and is not documented.
+*/
+typedef int (*sqlite3_callback)(void*,int,char**, char**);
+
+/*
+** CAPI3REF: One-Step Query Execution Interface
+**
+** The sqlite3_exec() interface is a convenience wrapper around
+** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()],
+** that allows an application to run multiple statements of SQL
+** without having to use a lot of C code. 
+**
+** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded,
+** semicolon-separate SQL statements passed into its 2nd argument,
+** in the context of the [database connection] passed in as its 1st
+** argument.  ^If the callback function of the 3rd argument to
+** sqlite3_exec() is not NULL, then it is invoked for each result row
+** coming out of the evaluated SQL statements.  ^The 4th argument to
+** to sqlite3_exec() is relayed through to the 1st argument of each
+** callback invocation.  ^If the callback pointer to sqlite3_exec()
+** is NULL, then no callback is ever invoked and result rows are
+** ignored.
+**
+** ^If an error occurs while evaluating the SQL statements passed into
+** sqlite3_exec(), then execution of the current statement stops and
+** subsequent statements are skipped.  ^If the 5th parameter to sqlite3_exec()
+** is not NULL then any error message is written into memory obtained
+** from [sqlite3_malloc()] and passed back through the 5th parameter.
+** To avoid memory leaks, the application should invoke [sqlite3_free()]
+** on error message strings returned through the 5th parameter of
+** of sqlite3_exec() after the error message string is no longer needed.
+** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors
+** occur, then sqlite3_exec() sets the pointer in its 5th parameter to
+** NULL before returning.
+**
+** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()
+** routine returns SQLITE_ABORT without invoking the callback again and
+** without running any subsequent SQL statements.
+**
+** ^The 2nd argument to the sqlite3_exec() callback function is the
+** number of columns in the result.  ^The 3rd argument to the sqlite3_exec()
+** callback is an array of pointers to strings obtained as if from
+** [sqlite3_column_text()], one for each column.  ^If an element of a
+** result row is NULL then the corresponding string pointer for the
+** sqlite3_exec() callback is a NULL pointer.  ^The 4th argument to the
+** sqlite3_exec() callback is an array of pointers to strings where each
+** entry represents the name of corresponding result column as obtained
+** from [sqlite3_column_name()].
+**
+** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer
+** to an empty string, or a pointer that contains only whitespace and/or 
+** SQL comments, then no SQL statements are evaluated and the database
+** is not changed.
+**
+** Restrictions:
+**
+** <ul>
+** <li> The application must insure that the 1st parameter to sqlite3_exec()
+**      is a valid and open [database connection].
+** <li> The application must not close [database connection] specified by
+**      the 1st parameter to sqlite3_exec() while sqlite3_exec() is running.
+** <li> The application must not modify the SQL statement text passed into
+**      the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running.
+** </ul>
+*/
+SQLITE_API int sqlite3_exec(
+  sqlite3*,                                  /* An open database */
+  const char *sql,                           /* SQL to be evaluated */
+  int (*callback)(void*,int,char**,char**),  /* Callback function */
+  void *,                                    /* 1st argument to callback */
+  char **errmsg                              /* Error msg written here */
+);
+
+/*
+** CAPI3REF: Result Codes
+** KEYWORDS: SQLITE_OK {error code} {error codes}
+** KEYWORDS: {result code} {result codes}
+**
+** Many SQLite functions return an integer result code from the set shown
+** here in order to indicates success or failure.
+**
+** New error codes may be added in future versions of SQLite.
+**
+** See also: [SQLITE_IOERR_READ | extended result codes]
+*/
+#define SQLITE_OK           0   /* Successful result */
+/* beginning-of-error-codes */
+#define SQLITE_ERROR        1   /* SQL error or missing database */
+#define SQLITE_INTERNAL     2   /* Internal logic error in SQLite */
+#define SQLITE_PERM         3   /* Access permission denied */
+#define SQLITE_ABORT        4   /* Callback routine requested an abort */
+#define SQLITE_BUSY         5   /* The database file is locked */
+#define SQLITE_LOCKED       6   /* A table in the database is locked */
+#define SQLITE_NOMEM        7   /* A malloc() failed */
+#define SQLITE_READONLY     8   /* Attempt to write a readonly database */
+#define SQLITE_INTERRUPT    9   /* Operation terminated by sqlite3_interrupt()*/
+#define SQLITE_IOERR       10   /* Some kind of disk I/O error occurred */
+#define SQLITE_CORRUPT     11   /* The database disk image is malformed */
+#define SQLITE_NOTFOUND    12   /* NOT USED. Table or record not found */
+#define SQLITE_FULL        13   /* Insertion failed because database is full */
+#define SQLITE_CANTOPEN    14   /* Unable to open the database file */
+#define SQLITE_PROTOCOL    15   /* Database lock protocol error */
+#define SQLITE_EMPTY       16   /* Database is empty */
+#define SQLITE_SCHEMA      17   /* The database schema changed */
+#define SQLITE_TOOBIG      18   /* String or BLOB exceeds size limit */
+#define SQLITE_CONSTRAINT  19   /* Abort due to constraint violation */
+#define SQLITE_MISMATCH    20   /* Data type mismatch */
+#define SQLITE_MISUSE      21   /* Library used incorrectly */
+#define SQLITE_NOLFS       22   /* Uses OS features not supported on host */
+#define SQLITE_AUTH        23   /* Authorization denied */
+#define SQLITE_FORMAT      24   /* Auxiliary database format error */
+#define SQLITE_RANGE       25   /* 2nd parameter to sqlite3_bind out of range */
+#define SQLITE_NOTADB      26   /* File opened that is not a database file */
+#define SQLITE_ROW         100  /* sqlite3_step() has another row ready */
+#define SQLITE_DONE        101  /* sqlite3_step() has finished executing */
+/* end-of-error-codes */
+
+/*
+** CAPI3REF: Extended Result Codes
+** KEYWORDS: {extended error code} {extended error codes}
+** KEYWORDS: {extended result code} {extended result codes}
+**
+** In its default configuration, SQLite API routines return one of 26 integer
+** [SQLITE_OK | result codes].  However, experience has shown that many of
+** these result codes are too coarse-grained.  They do not provide as
+** much information about problems as programmers might like.  In an effort to
+** address this, newer versions of SQLite (version 3.3.8 and later) include
+** support for additional result codes that provide more detailed information
+** about errors. The extended result codes are enabled or disabled
+** on a per database connection basis using the
+** [sqlite3_extended_result_codes()] API.
+**
+** Some of the available extended result codes are listed here.
+** One may expect the number of extended result codes will be expand
+** over time.  Software that uses extended result codes should expect
+** to see new result codes in future releases of SQLite.
+**
+** The SQLITE_OK result code will never be extended.  It will always
+** be exactly zero.
+*/
+#define SQLITE_IOERR_READ              (SQLITE_IOERR | (1<<8))
+#define SQLITE_IOERR_SHORT_READ        (SQLITE_IOERR | (2<<8))
+#define SQLITE_IOERR_WRITE             (SQLITE_IOERR | (3<<8))
+#define SQLITE_IOERR_FSYNC             (SQLITE_IOERR | (4<<8))
+#define SQLITE_IOERR_DIR_FSYNC         (SQLITE_IOERR | (5<<8))
+#define SQLITE_IOERR_TRUNCATE          (SQLITE_IOERR | (6<<8))
+#define SQLITE_IOERR_FSTAT             (SQLITE_IOERR | (7<<8))
+#define SQLITE_IOERR_UNLOCK            (SQLITE_IOERR | (8<<8))
+#define SQLITE_IOERR_RDLOCK            (SQLITE_IOERR | (9<<8))
+#define SQLITE_IOERR_DELETE            (SQLITE_IOERR | (10<<8))
+#define SQLITE_IOERR_BLOCKED           (SQLITE_IOERR | (11<<8))
+#define SQLITE_IOERR_NOMEM             (SQLITE_IOERR | (12<<8))
+#define SQLITE_IOERR_ACCESS            (SQLITE_IOERR | (13<<8))
+#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
+#define SQLITE_IOERR_LOCK              (SQLITE_IOERR | (15<<8))
+#define SQLITE_IOERR_CLOSE             (SQLITE_IOERR | (16<<8))
+#define SQLITE_IOERR_DIR_CLOSE         (SQLITE_IOERR | (17<<8))
+#define SQLITE_IOERR_SHMOPEN           (SQLITE_IOERR | (18<<8))
+#define SQLITE_IOERR_SHMSIZE           (SQLITE_IOERR | (19<<8))
+#define SQLITE_IOERR_SHMLOCK           (SQLITE_IOERR | (20<<8))
+#define SQLITE_LOCKED_SHAREDCACHE      (SQLITE_LOCKED |  (1<<8))
+#define SQLITE_BUSY_RECOVERY           (SQLITE_BUSY   |  (1<<8))
+#define SQLITE_CANTOPEN_NOTEMPDIR      (SQLITE_CANTOPEN | (1<<8))
+
+/*
+** CAPI3REF: Flags For File Open Operations
+**
+** These bit values are intended for use in the
+** 3rd parameter to the [sqlite3_open_v2()] interface and
+** in the 4th parameter to the xOpen method of the
+** [sqlite3_vfs] object.
+*/
+#define SQLITE_OPEN_READONLY         0x00000001  /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_READWRITE        0x00000002  /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_CREATE           0x00000004  /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_DELETEONCLOSE    0x00000008  /* VFS only */
+#define SQLITE_OPEN_EXCLUSIVE        0x00000010  /* VFS only */
+#define SQLITE_OPEN_AUTOPROXY        0x00000020  /* VFS only */
+#define SQLITE_OPEN_MAIN_DB          0x00000100  /* VFS only */
+#define SQLITE_OPEN_TEMP_DB          0x00000200  /* VFS only */
+#define SQLITE_OPEN_TRANSIENT_DB     0x00000400  /* VFS only */
+#define SQLITE_OPEN_MAIN_JOURNAL     0x00000800  /* VFS only */
+#define SQLITE_OPEN_TEMP_JOURNAL     0x00001000  /* VFS only */
+#define SQLITE_OPEN_SUBJOURNAL       0x00002000  /* VFS only */
+#define SQLITE_OPEN_MASTER_JOURNAL   0x00004000  /* VFS only */
+#define SQLITE_OPEN_NOMUTEX          0x00008000  /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_FULLMUTEX        0x00010000  /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_SHAREDCACHE      0x00020000  /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_PRIVATECACHE     0x00040000  /* Ok for sqlite3_open_v2() */
+#define SQLITE_OPEN_WAL              0x00080000  /* VFS only */
+
+/*
+** CAPI3REF: Device Characteristics
+**
+** The xDeviceCharacteristics method of the [sqlite3_io_methods]
+** object returns an integer which is a vector of the these
+** bit values expressing I/O characteristics of the mass storage
+** device that holds the file that the [sqlite3_io_methods]
+** refers to.
+**
+** The SQLITE_IOCAP_ATOMIC property means that all writes of
+** any size are atomic.  The SQLITE_IOCAP_ATOMICnnn values
+** mean that writes of blocks that are nnn bytes in size and
+** are aligned to an address which is an integer multiple of
+** nnn are atomic.  The SQLITE_IOCAP_SAFE_APPEND value means
+** that when data is appended to a file, the data is appended
+** first then the size of the file is extended, never the other
+** way around.  The SQLITE_IOCAP_SEQUENTIAL property means that
+** information is written to disk in the same order as calls
+** to xWrite().
+*/
+#define SQLITE_IOCAP_ATOMIC                 0x00000001
+#define SQLITE_IOCAP_ATOMIC512              0x00000002
+#define SQLITE_IOCAP_ATOMIC1K               0x00000004
+#define SQLITE_IOCAP_ATOMIC2K               0x00000008
+#define SQLITE_IOCAP_ATOMIC4K               0x00000010
+#define SQLITE_IOCAP_ATOMIC8K               0x00000020
+#define SQLITE_IOCAP_ATOMIC16K              0x00000040
+#define SQLITE_IOCAP_ATOMIC32K              0x00000080
+#define SQLITE_IOCAP_ATOMIC64K              0x00000100
+#define SQLITE_IOCAP_SAFE_APPEND            0x00000200
+#define SQLITE_IOCAP_SEQUENTIAL             0x00000400
+#define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN  0x00000800
+
+/*
+** CAPI3REF: File Locking Levels
+**
+** SQLite uses one of these integer values as the second
+** argument to calls it makes to the xLock() and xUnlock() methods
+** of an [sqlite3_io_methods] object.
+*/
+#define SQLITE_LOCK_NONE          0
+#define SQLITE_LOCK_SHARED        1
+#define SQLITE_LOCK_RESERVED      2
+#define SQLITE_LOCK_PENDING       3
+#define SQLITE_LOCK_EXCLUSIVE     4
+
+/*
+** CAPI3REF: Synchronization Type Flags
+**
+** When SQLite invokes the xSync() method of an
+** [sqlite3_io_methods] object it uses a combination of
+** these integer values as the second argument.
+**
+** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
+** sync operation only needs to flush data to mass storage.  Inode
+** information need not be flushed. If the lower four bits of the flag
+** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
+** If the lower four bits equal SQLITE_SYNC_FULL, that means
+** to use Mac OS X style fullsync instead of fsync().
+*/
+#define SQLITE_SYNC_NORMAL        0x00002
+#define SQLITE_SYNC_FULL          0x00003
+#define SQLITE_SYNC_DATAONLY      0x00010
+
+/*
+** CAPI3REF: OS Interface Open File Handle
+**
+** An [sqlite3_file] object represents an open file in the 
+** [sqlite3_vfs | OS interface layer].  Individual OS interface
+** implementations will
+** want to subclass this object by appending additional fields
+** for their own use.  The pMethods entry is a pointer to an
+** [sqlite3_io_methods] object that defines methods for performing
+** I/O operations on the open file.
+*/
+typedef struct sqlite3_file sqlite3_file;
+struct sqlite3_file {
+  const struct sqlite3_io_methods *pMethods;  /* Methods for an open file */
+};
+
+/*
+** CAPI3REF: OS Interface File Virtual Methods Object
+**
+** Every file opened by the [sqlite3_vfs] xOpen method populates an
+** [sqlite3_file] object (or, more commonly, a subclass of the
+** [sqlite3_file] object) with a pointer to an instance of this object.
+** This object defines the methods used to perform various operations
+** against the open file represented by the [sqlite3_file] object.
+**
+** If the xOpen method sets the sqlite3_file.pMethods element 
+** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
+** may be invoked even if the xOpen reported that it failed.  The
+** only way to prevent a call to xClose following a failed xOpen
+** is for the xOpen to set the sqlite3_file.pMethods element to NULL.
+**
+** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
+** [SQLITE_SYNC_FULL].  The first choice is the normal fsync().
+** The second choice is a Mac OS X style fullsync.  The [SQLITE_SYNC_DATAONLY]
+** flag may be ORed in to indicate that only the data of the file
+** and not its inode needs to be synced.
+**
+** The integer values to xLock() and xUnlock() are one of
+** <ul>
+** <li> [SQLITE_LOCK_NONE],
+** <li> [SQLITE_LOCK_SHARED],
+** <li> [SQLITE_LOCK_RESERVED],
+** <li> [SQLITE_LOCK_PENDING], or
+** <li> [SQLITE_LOCK_EXCLUSIVE].
+** </ul>
+** xLock() increases the lock. xUnlock() decreases the lock.
+** The xCheckReservedLock() method checks whether any database connection,
+** either in this process or in some other process, is holding a RESERVED,
+** PENDING, or EXCLUSIVE lock on the file.  It returns true
+** if such a lock exists and false otherwise.
+**
+** The xFileControl() method is a generic interface that allows custom
+** VFS implementations to directly control an open file using the
+** [sqlite3_file_control()] interface.  The second "op" argument is an
+** integer opcode.  The third argument is a generic pointer intended to
+** point to a structure that may contain arguments or space in which to
+** write return values.  Potential uses for xFileControl() might be
+** functions to enable blocking locks with timeouts, to change the
+** locking strategy (for example to use dot-file locks), to inquire
+** about the status of a lock, or to break stale locks.  The SQLite
+** core reserves all opcodes less than 100 for its own use.
+** A [SQLITE_FCNTL_LOCKSTATE | list of opcodes] less than 100 is available.
+** Applications that define a custom xFileControl method should use opcodes
+** greater than 100 to avoid conflicts.
+**
+** The xSectorSize() method returns the sector size of the
+** device that underlies the file.  The sector size is the
+** minimum write that can be performed without disturbing
+** other bytes in the file.  The xDeviceCharacteristics()
+** method returns a bit vector describing behaviors of the
+** underlying device:
+**
+** <ul>
+** <li> [SQLITE_IOCAP_ATOMIC]
+** <li> [SQLITE_IOCAP_ATOMIC512]
+** <li> [SQLITE_IOCAP_ATOMIC1K]
+** <li> [SQLITE_IOCAP_ATOMIC2K]
+** <li> [SQLITE_IOCAP_ATOMIC4K]
+** <li> [SQLITE_IOCAP_ATOMIC8K]
+** <li> [SQLITE_IOCAP_ATOMIC16K]
+** <li> [SQLITE_IOCAP_ATOMIC32K]
+** <li> [SQLITE_IOCAP_ATOMIC64K]
+** <li> [SQLITE_IOCAP_SAFE_APPEND]
+** <li> [SQLITE_IOCAP_SEQUENTIAL]
+** </ul>
+**
+** The SQLITE_IOCAP_ATOMIC property means that all writes of
+** any size are atomic.  The SQLITE_IOCAP_ATOMICnnn values
+** mean that writes of blocks that are nnn bytes in size and
+** are aligned to an address which is an integer multiple of
+** nnn are atomic.  The SQLITE_IOCAP_SAFE_APPEND value means
+** that when data is appended to a file, the data is appended
+** first then the size of the file is extended, never the other
+** way around.  The SQLITE_IOCAP_SEQUENTIAL property means that
+** information is written to disk in the same order as calls
+** to xWrite().
+**
+** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
+** in the unread portions of the buffer with zeros.  A VFS that
+** fails to zero-fill short reads might seem to work.  However,
+** failure to zero-fill short reads will eventually lead to
+** database corruption.
+*/
+typedef struct sqlite3_io_methods sqlite3_io_methods;
+struct sqlite3_io_methods {
+  int iVersion;
+  int (*xClose)(sqlite3_file*);
+  int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
+  int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
+  int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
+  int (*xSync)(sqlite3_file*, int flags);
+  int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
+  int (*xLock)(sqlite3_file*, int);
+  int (*xUnlock)(sqlite3_file*, int);
+  int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
+  int (*xFileControl)(sqlite3_file*, int op, void *pArg);
+  int (*xSectorSize)(sqlite3_file*);
+  int (*xDeviceCharacteristics)(sqlite3_file*);
+  /* Methods above are valid for version 1 */
+  int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
+  int (*xShmLock)(sqlite3_file*, int offset, int n, int flags);
+  void (*xShmBarrier)(sqlite3_file*);
+  int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
+  /* Methods above are valid for version 2 */
+  /* Additional methods may be added in future releases */
+};
+
+/*
+** CAPI3REF: Standard File Control Opcodes
+**
+** These integer constants are opcodes for the xFileControl method
+** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
+** interface.
+**
+** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging.  This
+** opcode causes the xFileControl method to write the current state of
+** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
+** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
+** into an integer that the pArg argument points to. This capability
+** is used during testing and only needs to be supported when SQLITE_TEST
+** is defined.
+**
+** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
+** layer a hint of how large the database file will grow to be during the
+** current transaction.  This hint is not guaranteed to be accurate but it
+** is often close.  The underlying VFS might choose to preallocate database
+** file space based on this hint in order to help writes to the database
+** file run faster.
+**
+** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
+** extends and truncates the database file in chunks of a size specified
+** by the user. The fourth argument to [sqlite3_file_control()] should 
+** point to an integer (type int) containing the new chunk-size to use
+** for the nominated database. Allocating database file space in large
+** chunks (say 1MB at a time), may reduce file-system fragmentation and
+** improve performance on some systems.
+*/
+#define SQLITE_FCNTL_LOCKSTATE        1
+#define SQLITE_GET_LOCKPROXYFILE      2
+#define SQLITE_SET_LOCKPROXYFILE      3
+#define SQLITE_LAST_ERRNO             4
+#define SQLITE_FCNTL_SIZE_HINT        5
+#define SQLITE_FCNTL_CHUNK_SIZE       6
+
+/*
+** CAPI3REF: Mutex Handle
+**
+** The mutex module within SQLite defines [sqlite3_mutex] to be an
+** abstract type for a mutex object.  The SQLite core never looks
+** at the internal representation of an [sqlite3_mutex].  It only
+** deals with pointers to the [sqlite3_mutex] object.
+**
+** Mutexes are created using [sqlite3_mutex_alloc()].
+*/
+typedef struct sqlite3_mutex sqlite3_mutex;
+
+/*
+** CAPI3REF: OS Interface Object
+**
+** An instance of the sqlite3_vfs object defines the interface between
+** the SQLite core and the underlying operating system.  The "vfs"
+** in the name of the object stands for "virtual file system".
+**
+** The value of the iVersion field is initially 1 but may be larger in
+** future versions of SQLite.  Additional fields may be appended to this
+** object when the iVersion value is increased.  Note that the structure
+** of the sqlite3_vfs object changes in the transaction between
+** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not
+** modified.
+**
+** The szOsFile field is the size of the subclassed [sqlite3_file]
+** structure used by this VFS.  mxPathname is the maximum length of
+** a pathname in this VFS.
+**
+** Registered sqlite3_vfs objects are kept on a linked list formed by
+** the pNext pointer.  The [sqlite3_vfs_register()]
+** and [sqlite3_vfs_unregister()] interfaces manage this list
+** in a thread-safe way.  The [sqlite3_vfs_find()] interface
+** searches the list.  Neither the application code nor the VFS
+** implementation should use the pNext pointer.
+**
+** The pNext field is the only field in the sqlite3_vfs
+** structure that SQLite will ever modify.  SQLite will only access
+** or modify this field while holding a particular static mutex.
+** The application should never modify anything within the sqlite3_vfs
+** object once the object has been registered.
+**
+** The zName field holds the name of the VFS module.  The name must
+** be unique across all VFS modules.
+**
+** ^SQLite guarantees that the zFilename parameter to xOpen
+** is either a NULL pointer or string obtained
+** from xFullPathname() with an optional suffix added.
+** ^If a suffix is added to the zFilename parameter, it will
+** consist of a single "-" character followed by no more than
+** 10 alphanumeric and/or "-" characters.
+** ^SQLite further guarantees that
+** the string will be valid and unchanged until xClose() is
+** called. Because of the previous sentence,
+** the [sqlite3_file] can safely store a pointer to the
+** filename if it needs to remember the filename for some reason.
+** If the zFilename parameter to xOpen is a NULL pointer then xOpen
+** must invent its own temporary name for the file.  ^Whenever the 
+** xFilename parameter is NULL it will also be the case that the
+** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
+**
+** The flags argument to xOpen() includes all bits set in
+** the flags argument to [sqlite3_open_v2()].  Or if [sqlite3_open()]
+** or [sqlite3_open16()] is used, then flags includes at least
+** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. 
+** If xOpen() opens a file read-only then it sets *pOutFlags to
+** include [SQLITE_OPEN_READONLY].  Other bits in *pOutFlags may be set.
+**
+** ^(SQLite will also add one of the following flags to the xOpen()
+** call, depending on the object being opened:
+**
+** <ul>
+** <li>  [SQLITE_OPEN_MAIN_DB]
+** <li>  [SQLITE_OPEN_MAIN_JOURNAL]
+** <li>  [SQLITE_OPEN_TEMP_DB]
+** <li>  [SQLITE_OPEN_TEMP_JOURNAL]
+** <li>  [SQLITE_OPEN_TRANSIENT_DB]
+** <li>  [SQLITE_OPEN_SUBJOURNAL]
+** <li>  [SQLITE_OPEN_MASTER_JOURNAL]
+** <li>  [SQLITE_OPEN_WAL]
+** </ul>)^
+**
+** The file I/O implementation can use the object type flags to
+** change the way it deals with files.  For example, an application
+** that does not care about crash recovery or rollback might make
+** the open of a journal file a no-op.  Writes to this journal would
+** also be no-ops, and any attempt to read the journal would return
+** SQLITE_IOERR.  Or the implementation might recognize that a database
+** file will be doing page-aligned sector reads and writes in a random
+** order and set up its I/O subsystem accordingly.
+**
+** SQLite might also add one of the following flags to the xOpen method:
+**
+** <ul>
+** <li> [SQLITE_OPEN_DELETEONCLOSE]
+** <li> [SQLITE_OPEN_EXCLUSIVE]
+** </ul>
+**
+** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
+** deleted when it is closed.  ^The [SQLITE_OPEN_DELETEONCLOSE]
+** will be set for TEMP databases and their journals, transient
+** databases, and subjournals.
+**
+** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
+** with the [SQLITE_OPEN_CREATE] flag, which are both directly
+** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
+** API.  The SQLITE_OPEN_EXCLUSIVE flag, when paired with the 
+** SQLITE_OPEN_CREATE, is used to indicate that file should always
+** be created, and that it is an error if it already exists.
+** It is <i>not</i> used to indicate the file should be opened 
+** for exclusive access.
+**
+** ^At least szOsFile bytes of memory are allocated by SQLite
+** to hold the  [sqlite3_file] structure passed as the third
+** argument to xOpen.  The xOpen method does not have to
+** allocate the structure; it should just fill it in.  Note that
+** the xOpen method must set the sqlite3_file.pMethods to either
+** a valid [sqlite3_io_methods] object or to NULL.  xOpen must do
+** this even if the open fails.  SQLite expects that the sqlite3_file.pMethods
+** element will be valid after xOpen returns regardless of the success
+** or failure of the xOpen call.
+**
+** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
+** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
+** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
+** to test whether a file is at least readable.   The file can be a
+** directory.
+**
+** ^SQLite will always allocate at least mxPathname+1 bytes for the
+** output buffer xFullPathname.  The exact size of the output buffer
+** is also passed as a parameter to both  methods. If the output buffer
+** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
+** handled as a fatal error by SQLite, vfs implementations should endeavor
+** to prevent this by setting mxPathname to a sufficiently large value.
+**
+** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64()
+** interfaces are not strictly a part of the filesystem, but they are
+** included in the VFS structure for completeness.
+** The xRandomness() function attempts to return nBytes bytes
+** of good-quality randomness into zOut.  The return value is
+** the actual number of bytes of randomness obtained.
+** The xSleep() method causes the calling thread to sleep for at
+** least the number of microseconds given.  ^The xCurrentTime()
+** method returns a Julian Day Number for the current date and time as
+** a floating point value.
+** ^The xCurrentTimeInt64() method returns, as an integer, the Julian
+** Day Number multipled by 86400000 (the number of milliseconds in 
+** a 24-hour day).  
+** ^SQLite will use the xCurrentTimeInt64() method to get the current
+** date and time if that method is available (if iVersion is 2 or 
+** greater and the function pointer is not NULL) and will fall back
+** to xCurrentTime() if xCurrentTimeInt64() is unavailable.
+*/
+typedef struct sqlite3_vfs sqlite3_vfs;
+struct sqlite3_vfs {
+  int iVersion;            /* Structure version number (currently 2) */
+  int szOsFile;            /* Size of subclassed sqlite3_file */
+  int mxPathname;          /* Maximum file pathname length */
+  sqlite3_vfs *pNext;      /* Next registered VFS */
+  const char *zName;       /* Name of this virtual file system */
+  void *pAppData;          /* Pointer to application-specific data */
+  int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
+               int flags, int *pOutFlags);
+  int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
+  int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
+  int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
+  void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
+  void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
+  void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);
+  void (*xDlClose)(sqlite3_vfs*, void*);
+  int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
+  int (*xSleep)(sqlite3_vfs*, int microseconds);
+  int (*xCurrentTime)(sqlite3_vfs*, double*);
+  int (*xGetLastError)(sqlite3_vfs*, int, char *);
+  /*
+  ** The methods above are in version 1 of the sqlite_vfs object
+  ** definition.  Those that follow are added in version 2 or later
+  */
+  int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*);
+  /*
+  ** The methods above are in versions 1 and 2 of the sqlite_vfs object.
+  ** New fields may be appended in figure versions.  The iVersion
+  ** value will increment whenever this happens. 
+  */
+};
+
+/*
+** CAPI3REF: Flags for the xAccess VFS method
+**
+** These integer constants can be used as the third parameter to
+** the xAccess method of an [sqlite3_vfs] object.  They determine
+** what kind of permissions the xAccess method is looking for.
+** With SQLITE_ACCESS_EXISTS, the xAccess method
+** simply checks whether the file exists.
+** With SQLITE_ACCESS_READWRITE, the xAccess method
+** checks whether the named directory is both readable and writable
+** (in other words, if files can be added, removed, and renamed within
+** the directory).
+** The SQLITE_ACCESS_READWRITE constant is currently used only by the
+** [temp_store_directory pragma], though this could change in a future
+** release of SQLite.
+** With SQLITE_ACCESS_READ, the xAccess method
+** checks whether the file is readable.  The SQLITE_ACCESS_READ constant is
+** currently unused, though it might be used in a future release of
+** SQLite.
+*/
+#define SQLITE_ACCESS_EXISTS    0
+#define SQLITE_ACCESS_READWRITE 1   /* Used by PRAGMA temp_store_directory */
+#define SQLITE_ACCESS_READ      2   /* Unused */
+
+/*
+** CAPI3REF: Flags for the xShmLock VFS method
+**
+** These integer constants define the various locking operations
+** allowed by the xShmLock method of [sqlite3_io_methods].  The
+** following are the only legal combinations of flags to the
+** xShmLock method:
+**
+** <ul>
+** <li>  SQLITE_SHM_LOCK | SQLITE_SHM_SHARED
+** <li>  SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE
+** <li>  SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED
+** <li>  SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE
+** </ul>
+**
+** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as
+** was given no the corresponding lock.  
+**
+** The xShmLock method can transition between unlocked and SHARED or
+** between unlocked and EXCLUSIVE.  It cannot transition between SHARED
+** and EXCLUSIVE.
+*/
+#define SQLITE_SHM_UNLOCK       1
+#define SQLITE_SHM_LOCK         2
+#define SQLITE_SHM_SHARED       4
+#define SQLITE_SHM_EXCLUSIVE    8
+
+/*
+** CAPI3REF: Maximum xShmLock index
+**
+** The xShmLock method on [sqlite3_io_methods] may use values
+** between 0 and this upper bound as its "offset" argument.
+** The SQLite core will never attempt to acquire or release a
+** lock outside of this range
+*/
+#define SQLITE_SHM_NLOCK        8
+
+
+/*
+** CAPI3REF: Initialize The SQLite Library
+**
+** ^The sqlite3_initialize() routine initializes the
+** SQLite library.  ^The sqlite3_shutdown() routine
+** deallocates any resources that were allocated by sqlite3_initialize().
+** These routines are designed to aid in process initialization and
+** shutdown on embedded systems.  Workstation applications using
+** SQLite normally do not need to invoke either of these routines.
+**
+** A call to sqlite3_initialize() is an "effective" call if it is
+** the first time sqlite3_initialize() is invoked during the lifetime of
+** the process, or if it is the first time sqlite3_initialize() is invoked
+** following a call to sqlite3_shutdown().  ^(Only an effective call
+** of sqlite3_initialize() does any initialization.  All other calls
+** are harmless no-ops.)^
+**
+** A call to sqlite3_shutdown() is an "effective" call if it is the first
+** call to sqlite3_shutdown() since the last sqlite3_initialize().  ^(Only
+** an effective call to sqlite3_shutdown() does any deinitialization.
+** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^
+**
+** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown()
+** is not.  The sqlite3_shutdown() interface must only be called from a
+** single thread.  All open [database connections] must be closed and all
+** other SQLite resources must be deallocated prior to invoking
+** sqlite3_shutdown().
+**
+** Among other things, ^sqlite3_initialize() will invoke
+** sqlite3_os_init().  Similarly, ^sqlite3_shutdown()
+** will invoke sqlite3_os_end().
+**
+** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success.
+** ^If for some reason, sqlite3_initialize() is unable to initialize
+** the library (perhaps it is unable to allocate a needed resource such
+** as a mutex) it returns an [error code] other than [SQLITE_OK].
+**
+** ^The sqlite3_initialize() routine is called internally by many other
+** SQLite interfaces so that an application usually does not need to
+** invoke sqlite3_initialize() directly.  For example, [sqlite3_open()]
+** calls sqlite3_initialize() so the SQLite library will be automatically
+** initialized when [sqlite3_open()] is called if it has not be initialized
+** already.  ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
+** compile-time option, then the automatic calls to sqlite3_initialize()
+** are omitted and the application must call sqlite3_initialize() directly
+** prior to using any other SQLite interface.  For maximum portability,
+** it is recommended that applications always invoke sqlite3_initialize()
+** directly prior to using any other SQLite interface.  Future releases
+** of SQLite may require this.  In other words, the behavior exhibited
+** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
+** default behavior in some future release of SQLite.
+**
+** The sqlite3_os_init() routine does operating-system specific
+** initialization of the SQLite library.  The sqlite3_os_end()
+** routine undoes the effect of sqlite3_os_init().  Typical tasks
+** performed by these routines include allocation or deallocation
+** of static resources, initialization of global variables,
+** setting up a default [sqlite3_vfs] module, or setting up
+** a default configuration using [sqlite3_config()].
+**
+** The application should never invoke either sqlite3_os_init()
+** or sqlite3_os_end() directly.  The application should only invoke
+** sqlite3_initialize() and sqlite3_shutdown().  The sqlite3_os_init()
+** interface is called automatically by sqlite3_initialize() and
+** sqlite3_os_end() is called by sqlite3_shutdown().  Appropriate
+** implementations for sqlite3_os_init() and sqlite3_os_end()
+** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
+** When [custom builds | built for other platforms]
+** (using the [SQLITE_OS_OTHER=1] compile-time
+** option) the application must supply a suitable implementation for
+** sqlite3_os_init() and sqlite3_os_end().  An application-supplied
+** implementation of sqlite3_os_init() or sqlite3_os_end()
+** must return [SQLITE_OK] on success and some other [error code] upon
+** failure.
+*/
+SQLITE_API int sqlite3_initialize(void);
+SQLITE_API int sqlite3_shutdown(void);
+SQLITE_API int sqlite3_os_init(void);
+SQLITE_API int sqlite3_os_end(void);
+
+/*
+** CAPI3REF: Configuring The SQLite Library
+**
+** The sqlite3_config() interface is used to make global configuration
+** changes to SQLite in order to tune SQLite to the specific needs of
+** the application.  The default configuration is recommended for most
+** applications and so this routine is usually not necessary.  It is
+** provided to support rare applications with unusual needs.
+**
+** The sqlite3_config() interface is not threadsafe.  The application
+** must insure that no other SQLite interfaces are invoked by other
+** threads while sqlite3_config() is running.  Furthermore, sqlite3_config()
+** may only be invoked prior to library initialization using
+** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
+** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
+** [sqlite3_shutdown()] then it will return SQLITE_MISUSE.
+** Note, however, that ^sqlite3_config() can be called as part of the
+** implementation of an application-defined [sqlite3_os_init()].
+**
+** The first argument to sqlite3_config() is an integer
+** [SQLITE_CONFIG_SINGLETHREAD | configuration option] that determines
+** what property of SQLite is to be configured.  Subsequent arguments
+** vary depending on the [SQLITE_CONFIG_SINGLETHREAD | configuration option]
+** in the first argument.
+**
+** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
+** ^If the option is unknown or SQLite is unable to set the option
+** then this routine returns a non-zero [error code].
+*/
+SQLITE_API int sqlite3_config(int, ...);
+
+/*
+** CAPI3REF: Configure database connections
+**
+** The sqlite3_db_config() interface is used to make configuration
+** changes to a [database connection].  The interface is similar to
+** [sqlite3_config()] except that the changes apply to a single
+** [database connection] (specified in the first argument).  The
+** sqlite3_db_config() interface should only be used immediately after
+** the database connection is created using [sqlite3_open()],
+** [sqlite3_open16()], or [sqlite3_open_v2()].  
+**
+** The second argument to sqlite3_db_config(D,V,...)  is the
+** configuration verb - an integer code that indicates what
+** aspect of the [database connection] is being configured.
+** The only choice for this value is [SQLITE_DBCONFIG_LOOKASIDE].
+** New verbs are likely to be added in future releases of SQLite.
+** Additional arguments depend on the verb.
+**
+** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if
+** the call is considered successful.
+*/
+SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...);
+
+/*
+** CAPI3REF: Memory Allocation Routines
+**
+** An instance of this object defines the interface between SQLite
+** and low-level memory allocation routines.
+**
+** This object is used in only one place in the SQLite interface.
+** A pointer to an instance of this object is the argument to
+** [sqlite3_config()] when the configuration option is
+** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].  
+** By creating an instance of this object
+** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
+** during configuration, an application can specify an alternative
+** memory allocation subsystem for SQLite to use for all of its
+** dynamic memory needs.
+**
+** Note that SQLite comes with several [built-in memory allocators]
+** that are perfectly adequate for the overwhelming majority of applications
+** and that this object is only useful to a tiny minority of applications
+** with specialized memory allocation requirements.  This object is
+** also used during testing of SQLite in order to specify an alternative
+** memory allocator that simulates memory out-of-memory conditions in
+** order to verify that SQLite recovers gracefully from such
+** conditions.
+**
+** The xMalloc and xFree methods must work like the
+** malloc() and free() functions from the standard C library.
+** The xRealloc method must work like realloc() from the standard C library
+** with the exception that if the second argument to xRealloc is zero,
+** xRealloc must be a no-op - it must not perform any allocation or
+** deallocation.  ^SQLite guarantees that the second argument to
+** xRealloc is always a value returned by a prior call to xRoundup.
+** And so in cases where xRoundup always returns a positive number,
+** xRealloc can perform exactly as the standard library realloc() and
+** still be in compliance with this specification.
+**
+** xSize should return the allocated size of a memory allocation
+** previously obtained from xMalloc or xRealloc.  The allocated size
+** is always at least as big as the requested size but may be larger.
+**
+** The xRoundup method returns what would be the allocated size of
+** a memory allocation given a particular requested size.  Most memory
+** allocators round up memory allocations at least to the next multiple
+** of 8.  Some allocators round up to a larger multiple or to a power of 2.
+** Every memory allocation request coming in through [sqlite3_malloc()]
+** or [sqlite3_realloc()] first calls xRoundup.  If xRoundup returns 0, 
+** that causes the corresponding memory allocation to fail.
+**
+** The xInit method initializes the memory allocator.  (For example,
+** it might allocate any require mutexes or initialize internal data
+** structures.  The xShutdown method is invoked (indirectly) by
+** [sqlite3_shutdown()] and should deallocate any resources acquired
+** by xInit.  The pAppData pointer is used as the only parameter to
+** xInit and xShutdown.
+**
+** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes
+** the xInit method, so the xInit method need not be threadsafe.  The
+** xShutdown method is only called from [sqlite3_shutdown()] so it does
+** not need to be threadsafe either.  For all other methods, SQLite
+** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
+** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
+** it is by default) and so the methods are automatically serialized.
+** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
+** methods must be threadsafe or else make their own arrangements for
+** serialization.
+**
+** SQLite will never invoke xInit() more than once without an intervening
+** call to xShutdown().
+*/
+typedef struct sqlite3_mem_methods sqlite3_mem_methods;
+struct sqlite3_mem_methods {
+  void *(*xMalloc)(int);         /* Memory allocation function */
+  void (*xFree)(void*);          /* Free a prior allocation */
+  void *(*xRealloc)(void*,int);  /* Resize an allocation */
+  int (*xSize)(void*);           /* Return the size of an allocation */
+  int (*xRoundup)(int);          /* Round up request size to allocation size */
+  int (*xInit)(void*);           /* Initialize the memory allocator */
+  void (*xShutdown)(void*);      /* Deinitialize the memory allocator */
+  void *pAppData;                /* Argument to xInit() and xShutdown() */
+};
+
+/*
+** CAPI3REF: Configuration Options
+**
+** These constants are the available integer configuration options that
+** can be passed as the first argument to the [sqlite3_config()] interface.
+**
+** New configuration options may be added in future releases of SQLite.
+** Existing configuration options might be discontinued.  Applications
+** should check the return code from [sqlite3_config()] to make sure that
+** the call worked.  The [sqlite3_config()] interface will return a
+** non-zero [error code] if a discontinued or unsupported configuration option
+** is invoked.
+**
+** <dl>
+** <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
+** <dd>There are no arguments to this option.  ^This option sets the
+** [threading mode] to Single-thread.  In other words, it disables
+** all mutexing and puts SQLite into a mode where it can only be used
+** by a single thread.   ^If SQLite is compiled with
+** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
+** it is not possible to change the [threading mode] from its default
+** value of Single-thread and so [sqlite3_config()] will return 
+** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD
+** configuration option.</dd>
+**
+** <dt>SQLITE_CONFIG_MULTITHREAD</dt>
+** <dd>There are no arguments to this option.  ^This option sets the
+** [threading mode] to Multi-thread.  In other words, it disables
+** mutexing on [database connection] and [prepared statement] objects.
+** The application is responsible for serializing access to
+** [database connections] and [prepared statements].  But other mutexes
+** are enabled so that SQLite will be safe to use in a multi-threaded
+** environment as long as no two threads attempt to use the same
+** [database connection] at the same time.  ^If SQLite is compiled with
+** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
+** it is not possible to set the Multi-thread [threading mode] and
+** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
+** SQLITE_CONFIG_MULTITHREAD configuration option.</dd>
+**
+** <dt>SQLITE_CONFIG_SERIALIZED</dt>
+** <dd>There are no arguments to this option.  ^This option sets the
+** [threading mode] to Serialized. In other words, this option enables
+** all mutexes including the recursive
+** mutexes on [database connection] and [prepared statement] objects.
+** In this mode (which is the default when SQLite is compiled with
+** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
+** to [database connections] and [prepared statements] so that the
+** application is free to use the same [database connection] or the
+** same [prepared statement] in different threads at the same time.
+** ^If SQLite is compiled with
+** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
+** it is not possible to set the Serialized [threading mode] and
+** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
+** SQLITE_CONFIG_SERIALIZED configuration option.</dd>
+**
+** <dt>SQLITE_CONFIG_MALLOC</dt>
+** <dd> ^(This option takes a single argument which is a pointer to an
+** instance of the [sqlite3_mem_methods] structure.  The argument specifies
+** alternative low-level memory allocation routines to be used in place of
+** the memory allocation routines built into SQLite.)^ ^SQLite makes
+** its own private copy of the content of the [sqlite3_mem_methods] structure
+** before the [sqlite3_config()] call returns.</dd>
+**
+** <dt>SQLITE_CONFIG_GETMALLOC</dt>
+** <dd> ^(This option takes a single argument which is a pointer to an
+** instance of the [sqlite3_mem_methods] structure.  The [sqlite3_mem_methods]
+** structure is filled with the currently defined memory allocation routines.)^
+** This option can be used to overload the default memory allocation
+** routines with a wrapper that simulations memory allocation failure or
+** tracks memory usage, for example. </dd>
+**
+** <dt>SQLITE_CONFIG_MEMSTATUS</dt>
+** <dd> ^This option takes single argument of type int, interpreted as a 
+** boolean, which enables or disables the collection of memory allocation 
+** statistics. ^(When memory allocation statistics are disabled, the 
+** following SQLite interfaces become non-operational:
+**   <ul>
+**   <li> [sqlite3_memory_used()]
+**   <li> [sqlite3_memory_highwater()]
+**   <li> [sqlite3_soft_heap_limit64()]
+**   <li> [sqlite3_status()]
+**   </ul>)^
+** ^Memory allocation statistics are enabled by default unless SQLite is
+** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory
+** allocation statistics are disabled by default.
+** </dd>
+**
+** <dt>SQLITE_CONFIG_SCRATCH</dt>
+** <dd> ^This option specifies a static memory buffer that SQLite can use for
+** scratch memory.  There are three arguments:  A pointer an 8-byte
+** aligned memory buffer from which the scrach allocations will be
+** drawn, the size of each scratch allocation (sz),
+** and the maximum number of scratch allocations (N).  The sz
+** argument must be a multiple of 16.
+** The first argument must be a pointer to an 8-byte aligned buffer
+** of at least sz*N bytes of memory.
+** ^SQLite will use no more than two scratch buffers per thread.  So
+** N should be set to twice the expected maximum number of threads.
+** ^SQLite will never require a scratch buffer that is more than 6
+** times the database page size. ^If SQLite needs needs additional
+** scratch memory beyond what is provided by this configuration option, then 
+** [sqlite3_malloc()] will be used to obtain the memory needed.</dd>
+**
+** <dt>SQLITE_CONFIG_PAGECACHE</dt>
+** <dd> ^This option specifies a static memory buffer that SQLite can use for
+** the database page cache with the default page cache implemenation.  
+** This configuration should not be used if an application-define page
+** cache implementation is loaded using the SQLITE_CONFIG_PCACHE option.
+** There are three arguments to this option: A pointer to 8-byte aligned
+** memory, the size of each page buffer (sz), and the number of pages (N).
+** The sz argument should be the size of the largest database page
+** (a power of two between 512 and 32768) plus a little extra for each
+** page header.  ^The page header size is 20 to 40 bytes depending on
+** the host architecture.  ^It is harmless, apart from the wasted memory,
+** to make sz a little too large.  The first
+** argument should point to an allocation of at least sz*N bytes of memory.
+** ^SQLite will use the memory provided by the first argument to satisfy its
+** memory needs for the first N pages that it adds to cache.  ^If additional
+** page cache memory is needed beyond what is provided by this option, then
+** SQLite goes to [sqlite3_malloc()] for the additional storage space.
+** The pointer in the first argument must
+** be aligned to an 8-byte boundary or subsequent behavior of SQLite
+** will be undefined.</dd>
+**
+** <dt>SQLITE_CONFIG_HEAP</dt>
+** <dd> ^This option specifies a static memory buffer that SQLite will use
+** for all of its dynamic memory allocation needs beyond those provided
+** for by [SQLITE_CONFIG_SCRATCH] and [SQLITE_CONFIG_PAGECACHE].
+** There are three arguments: An 8-byte aligned pointer to the memory,
+** the number of bytes in the memory buffer, and the minimum allocation size.
+** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts
+** to using its default memory allocator (the system malloc() implementation),
+** undoing any prior invocation of [SQLITE_CONFIG_MALLOC].  ^If the
+** memory pointer is not NULL and either [SQLITE_ENABLE_MEMSYS3] or
+** [SQLITE_ENABLE_MEMSYS5] are defined, then the alternative memory
+** allocator is engaged to handle all of SQLites memory allocation needs.
+** The first pointer (the memory pointer) must be aligned to an 8-byte
+** boundary or subsequent behavior of SQLite will be undefined.</dd>
+**
+** <dt>SQLITE_CONFIG_MUTEX</dt>
+** <dd> ^(This option takes a single argument which is a pointer to an
+** instance of the [sqlite3_mutex_methods] structure.  The argument specifies
+** alternative low-level mutex routines to be used in place
+** the mutex routines built into SQLite.)^  ^SQLite makes a copy of the
+** content of the [sqlite3_mutex_methods] structure before the call to
+** [sqlite3_config()] returns. ^If SQLite is compiled with
+** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
+** the entire mutexing subsystem is omitted from the build and hence calls to
+** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will
+** return [SQLITE_ERROR].</dd>
+**
+** <dt>SQLITE_CONFIG_GETMUTEX</dt>
+** <dd> ^(This option takes a single argument which is a pointer to an
+** instance of the [sqlite3_mutex_methods] structure.  The
+** [sqlite3_mutex_methods]
+** structure is filled with the currently defined mutex routines.)^
+** This option can be used to overload the default mutex allocation
+** routines with a wrapper used to track mutex usage for performance
+** profiling or testing, for example.   ^If SQLite is compiled with
+** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
+** the entire mutexing subsystem is omitted from the build and hence calls to
+** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will
+** return [SQLITE_ERROR].</dd>
+**
+** <dt>SQLITE_CONFIG_LOOKASIDE</dt>
+** <dd> ^(This option takes two arguments that determine the default
+** memory allocation for the lookaside memory allocator on each
+** [database connection].  The first argument is the
+** size of each lookaside buffer slot and the second is the number of
+** slots allocated to each database connection.)^  ^(This option sets the
+** <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE]
+** verb to [sqlite3_db_config()] can be used to change the lookaside
+** configuration on individual connections.)^ </dd>
+**
+** <dt>SQLITE_CONFIG_PCACHE</dt>
+** <dd> ^(This option takes a single argument which is a pointer to
+** an [sqlite3_pcache_methods] object.  This object specifies the interface
+** to a custom page cache implementation.)^  ^SQLite makes a copy of the
+** object and uses it for page cache memory allocations.</dd>
+**
+** <dt>SQLITE_CONFIG_GETPCACHE</dt>
+** <dd> ^(This option takes a single argument which is a pointer to an
+** [sqlite3_pcache_methods] object.  SQLite copies of the current
+** page cache implementation into that object.)^ </dd>
+**
+** <dt>SQLITE_CONFIG_LOG</dt>
+** <dd> ^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
+** function with a call signature of void(*)(void*,int,const char*), 
+** and a pointer to void. ^If the function pointer is not NULL, it is
+** invoked by [sqlite3_log()] to process each logging event.  ^If the
+** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op.
+** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is
+** passed through as the first parameter to the application-defined logger
+** function whenever that function is invoked.  ^The second parameter to
+** the logger function is a copy of the first parameter to the corresponding
+** [sqlite3_log()] call and is intended to be a [result code] or an
+** [extended result code].  ^The third parameter passed to the logger is
+** log message after formatting via [sqlite3_snprintf()].
+** The SQLite logging interface is not reentrant; the logger function
+** supplied by the application must not invoke any SQLite interface.
+** In a multi-threaded application, the application-defined logger
+** function must be threadsafe. </dd>
+**
+** </dl>
+*/
+#define SQLITE_CONFIG_SINGLETHREAD  1  /* nil */
+#define SQLITE_CONFIG_MULTITHREAD   2  /* nil */
+#define SQLITE_CONFIG_SERIALIZED    3  /* nil */
+#define SQLITE_CONFIG_MALLOC        4  /* sqlite3_mem_methods* */
+#define SQLITE_CONFIG_GETMALLOC     5  /* sqlite3_mem_methods* */
+#define SQLITE_CONFIG_SCRATCH       6  /* void*, int sz, int N */
+#define SQLITE_CONFIG_PAGECACHE     7  /* void*, int sz, int N */
+#define SQLITE_CONFIG_HEAP          8  /* void*, int nByte, int min */
+#define SQLITE_CONFIG_MEMSTATUS     9  /* boolean */
+#define SQLITE_CONFIG_MUTEX        10  /* sqlite3_mutex_methods* */
+#define SQLITE_CONFIG_GETMUTEX     11  /* sqlite3_mutex_methods* */
+/* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */ 
+#define SQLITE_CONFIG_LOOKASIDE    13  /* int int */
+#define SQLITE_CONFIG_PCACHE       14  /* sqlite3_pcache_methods* */
+#define SQLITE_CONFIG_GETPCACHE    15  /* sqlite3_pcache_methods* */
+#define SQLITE_CONFIG_LOG          16  /* xFunc, void* */
+
+/*
+** CAPI3REF: Database Connection Configuration Options
+**
+** These constants are the available integer configuration options that
+** can be passed as the second argument to the [sqlite3_db_config()] interface.
+**
+** New configuration options may be added in future releases of SQLite.
+** Existing configuration options might be discontinued.  Applications
+** should check the return code from [sqlite3_db_config()] to make sure that
+** the call worked.  ^The [sqlite3_db_config()] interface will return a
+** non-zero [error code] if a discontinued or unsupported configuration option
+** is invoked.
+**
+** <dl>
+** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
+** <dd> ^This option takes three additional arguments that determine the 
+** [lookaside memory allocator] configuration for the [database connection].
+** ^The first argument (the third parameter to [sqlite3_db_config()] is a
+** pointer to an memory buffer to use for lookaside memory.
+** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb
+** may be NULL in which case SQLite will allocate the
+** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the
+** size of each lookaside buffer slot.  ^The third argument is the number of
+** slots.  The size of the buffer in the first argument must be greater than
+** or equal to the product of the second and third arguments.  The buffer
+** must be aligned to an 8-byte boundary.  ^If the second argument to
+** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally
+** rounded down to the next smaller multiple of 8.  ^(The lookaside memory
+** configuration for a database connection can only be changed when that
+** connection is not currently using lookaside memory, or in other words
+** when the "current value" returned by
+** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero.
+** Any attempt to change the lookaside memory configuration when lookaside
+** memory is in use leaves the configuration unchanged and returns 
+** [SQLITE_BUSY].)^</dd>
+**
+** </dl>
+*/
+#define SQLITE_DBCONFIG_LOOKASIDE    1001  /* void* int int */
+
+
+/*
+** CAPI3REF: Enable Or Disable Extended Result Codes
+**
+** ^The sqlite3_extended_result_codes() routine enables or disables the
+** [extended result codes] feature of SQLite. ^The extended result
+** codes are disabled by default for historical compatibility.
+*/
+SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff);
+
+/*
+** CAPI3REF: Last Insert Rowid
+**
+** ^Each entry in an SQLite table has a unique 64-bit signed
+** integer key called the [ROWID | "rowid"]. ^The rowid is always available
+** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
+** names are not also used by explicitly declared columns. ^If
+** the table has a column of type [INTEGER PRIMARY KEY] then that column
+** is another alias for the rowid.
+**
+** ^This routine returns the [rowid] of the most recent
+** successful [INSERT] into the database from the [database connection]
+** in the first argument.  ^If no successful [INSERT]s
+** have ever occurred on that database connection, zero is returned.
+**
+** ^(If an [INSERT] occurs within a trigger, then the [rowid] of the inserted
+** row is returned by this routine as long as the trigger is running.
+** But once the trigger terminates, the value returned by this routine
+** reverts to the last value inserted before the trigger fired.)^
+**
+** ^An [INSERT] that fails due to a constraint violation is not a
+** successful [INSERT] and does not change the value returned by this
+** routine.  ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
+** and INSERT OR ABORT make no changes to the return value of this
+** routine when their insertion fails.  ^(When INSERT OR REPLACE
+** encounters a constraint violation, it does not fail.  The
+** INSERT continues to completion after deleting rows that caused
+** the constraint problem so INSERT OR REPLACE will always change
+** the return value of this interface.)^
+**
+** ^For the purposes of this routine, an [INSERT] is considered to
+** be successful even if it is subsequently rolled back.
+**
+** This function is accessible to SQL statements via the
+** [last_insert_rowid() SQL function].
+**
+** If a separate thread performs a new [INSERT] on the same
+** database connection while the [sqlite3_last_insert_rowid()]
+** function is running and thus changes the last insert [rowid],
+** then the value returned by [sqlite3_last_insert_rowid()] is
+** unpredictable and might not equal either the old or the new
+** last insert [rowid].
+*/
+SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
+
+/*
+** CAPI3REF: Count The Number Of Rows Modified
+**
+** ^This function returns the number of database rows that were changed
+** or inserted or deleted by the most recently completed SQL statement
+** on the [database connection] specified by the first parameter.
+** ^(Only changes that are directly specified by the [INSERT], [UPDATE],
+** or [DELETE] statement are counted.  Auxiliary changes caused by
+** triggers or [foreign key actions] are not counted.)^ Use the
+** [sqlite3_total_changes()] function to find the total number of changes
+** including changes caused by triggers and foreign key actions.
+**
+** ^Changes to a view that are simulated by an [INSTEAD OF trigger]
+** are not counted.  Only real table changes are counted.
+**
+** ^(A "row change" is a change to a single row of a single table
+** caused by an INSERT, DELETE, or UPDATE statement.  Rows that
+** are changed as side effects of [REPLACE] constraint resolution,
+** rollback, ABORT processing, [DROP TABLE], or by any other
+** mechanisms do not count as direct row changes.)^
+**
+** A "trigger context" is a scope of execution that begins and
+** ends with the script of a [CREATE TRIGGER | trigger]. 
+** Most SQL statements are
+** evaluated outside of any trigger.  This is the "top level"
+** trigger context.  If a trigger fires from the top level, a
+** new trigger context is entered for the duration of that one
+** trigger.  Subtriggers create subcontexts for their duration.
+**
+** ^Calling [sqlite3_exec()] or [sqlite3_step()] recursively does
+** not create a new trigger context.
+**
+** ^This function returns the number of direct row changes in the
+** most recent INSERT, UPDATE, or DELETE statement within the same
+** trigger context.
+**
+** ^Thus, when called from the top level, this function returns the
+** number of changes in the most recent INSERT, UPDATE, or DELETE
+** that also occurred at the top level.  ^(Within the body of a trigger,
+** the sqlite3_changes() interface can be called to find the number of
+** changes in the most recently completed INSERT, UPDATE, or DELETE
+** statement within the body of the same trigger.
+** However, the number returned does not include changes
+** caused by subtriggers since those have their own context.)^
+**
+** See also the [sqlite3_total_changes()] interface, the
+** [count_changes pragma], and the [changes() SQL function].
+**
+** If a separate thread makes changes on the same database connection
+** while [sqlite3_changes()] is running then the value returned
+** is unpredictable and not meaningful.
+*/
+SQLITE_API int sqlite3_changes(sqlite3*);
+
+/*
+** CAPI3REF: Total Number Of Rows Modified
+**
+** ^This function returns the number of row changes caused by [INSERT],
+** [UPDATE] or [DELETE] statements since the [database connection] was opened.
+** ^(The count returned by sqlite3_total_changes() includes all changes
+** from all [CREATE TRIGGER | trigger] contexts and changes made by
+** [foreign key actions]. However,
+** the count does not include changes used to implement [REPLACE] constraints,
+** do rollbacks or ABORT processing, or [DROP TABLE] processing.  The
+** count does not include rows of views that fire an [INSTEAD OF trigger],
+** though if the INSTEAD OF trigger makes changes of its own, those changes 
+** are counted.)^
+** ^The sqlite3_total_changes() function counts the changes as soon as
+** the statement that makes them is completed (when the statement handle
+** is passed to [sqlite3_reset()] or [sqlite3_finalize()]).
+**
+** See also the [sqlite3_changes()] interface, the
+** [count_changes pragma], and the [total_changes() SQL function].
+**
+** If a separate thread makes changes on the same database connection
+** while [sqlite3_total_changes()] is running then the value
+** returned is unpredictable and not meaningful.
+*/
+SQLITE_API int sqlite3_total_changes(sqlite3*);
+
+/*
+** CAPI3REF: Interrupt A Long-Running Query
+**
+** ^This function causes any pending database operation to abort and
+** return at its earliest opportunity. This routine is typically
+** called in response to a user action such as pressing "Cancel"
+** or Ctrl-C where the user wants a long query operation to halt
+** immediately.
+**
+** ^It is safe to call this routine from a thread different from the
+** thread that is currently running the database operation.  But it
+** is not safe to call this routine with a [database connection] that
+** is closed or might close before sqlite3_interrupt() returns.
+**
+** ^If an SQL operation is very nearly finished at the time when
+** sqlite3_interrupt() is called, then it might not have an opportunity
+** to be interrupted and might continue to completion.
+**
+** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
+** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
+** that is inside an explicit transaction, then the entire transaction
+** will be rolled back automatically.
+**
+** ^The sqlite3_interrupt(D) call is in effect until all currently running
+** SQL statements on [database connection] D complete.  ^Any new SQL statements
+** that are started after the sqlite3_interrupt() call and before the 
+** running statements reaches zero are interrupted as if they had been
+** running prior to the sqlite3_interrupt() call.  ^New SQL statements
+** that are started after the running statement count reaches zero are
+** not effected by the sqlite3_interrupt().
+** ^A call to sqlite3_interrupt(D) that occurs when there are no running
+** SQL statements is a no-op and has no effect on SQL statements
+** that are started after the sqlite3_interrupt() call returns.
+**
+** If the database connection closes while [sqlite3_interrupt()]
+** is running then bad things will likely happen.
+*/
+SQLITE_API void sqlite3_interrupt(sqlite3*);
+
+/*
+** CAPI3REF: Determine If An SQL Statement Is Complete
+**
+** These routines are useful during command-line input to determine if the
+** currently entered text seems to form a complete SQL statement or
+** if additional input is needed before sending the text into
+** SQLite for parsing.  ^These routines return 1 if the input string
+** appears to be a complete SQL statement.  ^A statement is judged to be
+** complete if it ends with a semicolon token and is not a prefix of a
+** well-formed CREATE TRIGGER statement.  ^Semicolons that are embedded within
+** string literals or quoted identifier names or comments are not
+** independent tokens (they are part of the token in which they are
+** embedded) and thus do not count as a statement terminator.  ^Whitespace
+** and comments that follow the final semicolon are ignored.
+**
+** ^These routines return 0 if the statement is incomplete.  ^If a
+** memory allocation fails, then SQLITE_NOMEM is returned.
+**
+** ^These routines do not parse the SQL statements thus
+** will not detect syntactically incorrect SQL.
+**
+** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior 
+** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
+** automatically by sqlite3_complete16().  If that initialization fails,
+** then the return value from sqlite3_complete16() will be non-zero
+** regardless of whether or not the input SQL is complete.)^
+**
+** The input to [sqlite3_complete()] must be a zero-terminated
+** UTF-8 string.
+**
+** The input to [sqlite3_complete16()] must be a zero-terminated
+** UTF-16 string in native byte order.
+*/
+SQLITE_API int sqlite3_complete(const char *sql);
+SQLITE_API int sqlite3_complete16(const void *sql);
+
+/*
+** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
+**
+** ^This routine sets a callback function that might be invoked whenever
+** an attempt is made to open a database table that another thread
+** or process has locked.
+**
+** ^If the busy callback is NULL, then [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED]
+** is returned immediately upon encountering the lock.  ^If the busy callback
+** is not NULL, then the callback might be invoked with two arguments.
+**
+** ^The first argument to the busy handler is a copy of the void* pointer which
+** is the third argument to sqlite3_busy_handler().  ^The second argument to
+** the busy handler callback is the number of times that the busy handler has
+** been invoked for this locking event.  ^If the
+** busy callback returns 0, then no additional attempts are made to
+** access the database and [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED] is returned.
+** ^If the callback returns non-zero, then another attempt
+** is made to open the database for reading and the cycle repeats.
+**
+** The presence of a busy handler does not guarantee that it will be invoked
+** when there is lock contention. ^If SQLite determines that invoking the busy
+** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
+** or [SQLITE_IOERR_BLOCKED] instead of invoking the busy handler.
+** Consider a scenario where one process is holding a read lock that
+** it is trying to promote to a reserved lock and
+** a second process is holding a reserved lock that it is trying
+** to promote to an exclusive lock.  The first process cannot proceed
+** because it is blocked by the second and the second process cannot
+** proceed because it is blocked by the first.  If both processes
+** invoke the busy handlers, neither will make any progress.  Therefore,
+** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
+** will induce the first process to release its read lock and allow
+** the second process to proceed.
+**
+** ^The default busy callback is NULL.
+**
+** ^The [SQLITE_BUSY] error is converted to [SQLITE_IOERR_BLOCKED]
+** when SQLite is in the middle of a large transaction where all the
+** changes will not fit into the in-memory cache.  SQLite will
+** already hold a RESERVED lock on the database file, but it needs
+** to promote this lock to EXCLUSIVE so that it can spill cache
+** pages into the database file without harm to concurrent
+** readers.  ^If it is unable to promote the lock, then the in-memory
+** cache will be left in an inconsistent state and so the error
+** code is promoted from the relatively benign [SQLITE_BUSY] to
+** the more severe [SQLITE_IOERR_BLOCKED].  ^This error code promotion
+** forces an automatic rollback of the changes.  See the
+** <a href="/cvstrac/wiki?p=CorruptionFollowingBusyError">
+** CorruptionFollowingBusyError</a> wiki page for a discussion of why
+** this is important.
+**
+** ^(There can only be a single busy handler defined for each
+** [database connection].  Setting a new busy handler clears any
+** previously set handler.)^  ^Note that calling [sqlite3_busy_timeout()]
+** will also set or clear the busy handler.
+**
+** The busy callback should not take any actions which modify the
+** database connection that invoked the busy handler.  Any such actions
+** result in undefined behavior.
+** 
+** A busy handler must not close the database connection
+** or [prepared statement] that invoked the busy handler.
+*/
+SQLITE_API int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*);
+
+/*
+** CAPI3REF: Set A Busy Timeout
+**
+** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
+** for a specified amount of time when a table is locked.  ^The handler
+** will sleep multiple times until at least "ms" milliseconds of sleeping
+** have accumulated.  ^After at least "ms" milliseconds of sleeping,
+** the handler returns 0 which causes [sqlite3_step()] to return
+** [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED].
+**
+** ^Calling this routine with an argument less than or equal to zero
+** turns off all busy handlers.
+**
+** ^(There can only be a single busy handler for a particular
+** [database connection] any any given moment.  If another busy handler
+** was defined  (using [sqlite3_busy_handler()]) prior to calling
+** this routine, that other busy handler is cleared.)^
+*/
+SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms);
+
+/*
+** CAPI3REF: Convenience Routines For Running Queries
+**
+** Definition: A <b>result table</b> is memory data structure created by the
+** [sqlite3_get_table()] interface.  A result table records the
+** complete query results from one or more queries.
+**
+** The table conceptually has a number of rows and columns.  But
+** these numbers are not part of the result table itself.  These
+** numbers are obtained separately.  Let N be the number of rows
+** and M be the number of columns.
+**
+** A result table is an array of pointers to zero-terminated UTF-8 strings.
+** There are (N+1)*M elements in the array.  The first M pointers point
+** to zero-terminated strings that  contain the names of the columns.
+** The remaining entries all point to query results.  NULL values result
+** in NULL pointers.  All other values are in their UTF-8 zero-terminated
+** string representation as returned by [sqlite3_column_text()].
+**
+** A result table might consist of one or more memory allocations.
+** It is not safe to pass a result table directly to [sqlite3_free()].
+** A result table should be deallocated using [sqlite3_free_table()].
+**
+** As an example of the result table format, suppose a query result
+** is as follows:
+**
+** <blockquote><pre>
+**        Name        | Age
+**        -----------------------
+**        Alice       | 43
+**        Bob         | 28
+**        Cindy       | 21
+** </pre></blockquote>
+**
+** There are two column (M==2) and three rows (N==3).  Thus the
+** result table has 8 entries.  Suppose the result table is stored
+** in an array names azResult.  Then azResult holds this content:
+**
+** <blockquote><pre>
+**        azResult&#91;0] = "Name";
+**        azResult&#91;1] = "Age";
+**        azResult&#91;2] = "Alice";
+**        azResult&#91;3] = "43";
+**        azResult&#91;4] = "Bob";
+**        azResult&#91;5] = "28";
+**        azResult&#91;6] = "Cindy";
+**        azResult&#91;7] = "21";
+** </pre></blockquote>
+**
+** ^The sqlite3_get_table() function evaluates one or more
+** semicolon-separated SQL statements in the zero-terminated UTF-8
+** string of its 2nd parameter and returns a result table to the
+** pointer given in its 3rd parameter.
+**
+** After the application has finished with the result from sqlite3_get_table(),
+** it should pass the result table pointer to sqlite3_free_table() in order to
+** release the memory that was malloced.  Because of the way the
+** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
+** function must not try to call [sqlite3_free()] directly.  Only
+** [sqlite3_free_table()] is able to release the memory properly and safely.
+**
+** ^(The sqlite3_get_table() interface is implemented as a wrapper around
+** [sqlite3_exec()].  The sqlite3_get_table() routine does not have access
+** to any internal data structures of SQLite.  It uses only the public
+** interface defined here.  As a consequence, errors that occur in the
+** wrapper layer outside of the internal [sqlite3_exec()] call are not
+** reflected in subsequent calls to [sqlite3_errcode()] or
+** [sqlite3_errmsg()].)^
+*/
+SQLITE_API int sqlite3_get_table(
+  sqlite3 *db,          /* An open database */
+  const char *zSql,     /* SQL to be evaluated */
+  char ***pazResult,    /* Results of the query */
+  int *pnRow,           /* Number of result rows written here */
+  int *pnColumn,        /* Number of result columns written here */
+  char **pzErrmsg       /* Error msg written here */
+);
+SQLITE_API void sqlite3_free_table(char **result);
+
+/*
+** CAPI3REF: Formatted String Printing Functions
+**
+** These routines are work-alikes of the "printf()" family of functions
+** from the standard C library.
+**
+** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
+** results into memory obtained from [sqlite3_malloc()].
+** The strings returned by these two routines should be
+** released by [sqlite3_free()].  ^Both routines return a
+** NULL pointer if [sqlite3_malloc()] is unable to allocate enough
+** memory to hold the resulting string.
+**
+** ^(In sqlite3_snprintf() routine is similar to "snprintf()" from
+** the standard C library.  The result is written into the
+** buffer supplied as the second parameter whose size is given by
+** the first parameter. Note that the order of the
+** first two parameters is reversed from snprintf().)^  This is an
+** historical accident that cannot be fixed without breaking
+** backwards compatibility.  ^(Note also that sqlite3_snprintf()
+** returns a pointer to its buffer instead of the number of
+** characters actually written into the buffer.)^  We admit that
+** the number of characters written would be a more useful return
+** value but we cannot change the implementation of sqlite3_snprintf()
+** now without breaking compatibility.
+**
+** ^As long as the buffer size is greater than zero, sqlite3_snprintf()
+** guarantees that the buffer is always zero-terminated.  ^The first
+** parameter "n" is the total size of the buffer, including space for
+** the zero terminator.  So the longest string that can be completely
+** written will be n-1 characters.
+**
+** These routines all implement some additional formatting
+** options that are useful for constructing SQL statements.
+** All of the usual printf() formatting options apply.  In addition, there
+** is are "%q", "%Q", and "%z" options.
+**
+** ^(The %q option works like %s in that it substitutes a null-terminated
+** string from the argument list.  But %q also doubles every '\'' character.
+** %q is designed for use inside a string literal.)^  By doubling each '\''
+** character it escapes that character and allows it to be inserted into
+** the string.
+**
+** For example, assume the string variable zText contains text as follows:
+**
+** <blockquote><pre>
+**  char *zText = "It's a happy day!";
+** </pre></blockquote>
+**
+** One can use this text in an SQL statement as follows:
+**
+** <blockquote><pre>
+**  char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText);
+**  sqlite3_exec(db, zSQL, 0, 0, 0);
+**  sqlite3_free(zSQL);
+** </pre></blockquote>
+**
+** Because the %q format string is used, the '\'' character in zText
+** is escaped and the SQL generated is as follows:
+**
+** <blockquote><pre>
+**  INSERT INTO table1 VALUES('It''s a happy day!')
+** </pre></blockquote>
+**
+** This is correct.  Had we used %s instead of %q, the generated SQL
+** would have looked like this:
+**
+** <blockquote><pre>
+**  INSERT INTO table1 VALUES('It's a happy day!');
+** </pre></blockquote>
+**
+** This second example is an SQL syntax error.  As a general rule you should
+** always use %q instead of %s when inserting text into a string literal.
+**
+** ^(The %Q option works like %q except it also adds single quotes around
+** the outside of the total string.  Additionally, if the parameter in the
+** argument list is a NULL pointer, %Q substitutes the text "NULL" (without
+** single quotes).)^  So, for example, one could say:
+**
+** <blockquote><pre>
+**  char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
+**  sqlite3_exec(db, zSQL, 0, 0, 0);
+**  sqlite3_free(zSQL);
+** </pre></blockquote>
+**
+** The code above will render a correct SQL statement in the zSQL
+** variable even if the zText variable is a NULL pointer.
+**
+** ^(The "%z" formatting option works like "%s" but with the
+** addition that after the string has been read and copied into
+** the result, [sqlite3_free()] is called on the input string.)^
+*/
+SQLITE_API char *sqlite3_mprintf(const char*,...);
+SQLITE_API char *sqlite3_vmprintf(const char*, va_list);
+SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);
+
+/*
+** CAPI3REF: Memory Allocation Subsystem
+**
+** The SQLite core uses these three routines for all of its own
+** internal memory allocation needs. "Core" in the previous sentence
+** does not include operating-system specific VFS implementation.  The
+** Windows VFS uses native malloc() and free() for some operations.
+**
+** ^The sqlite3_malloc() routine returns a pointer to a block
+** of memory at least N bytes in length, where N is the parameter.
+** ^If sqlite3_malloc() is unable to obtain sufficient free
+** memory, it returns a NULL pointer.  ^If the parameter N to
+** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
+** a NULL pointer.
+**
+** ^Calling sqlite3_free() with a pointer previously returned
+** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
+** that it might be reused.  ^The sqlite3_free() routine is
+** a no-op if is called with a NULL pointer.  Passing a NULL pointer
+** to sqlite3_free() is harmless.  After being freed, memory
+** should neither be read nor written.  Even reading previously freed
+** memory might result in a segmentation fault or other severe error.
+** Memory corruption, a segmentation fault, or other severe error
+** might result if sqlite3_free() is called with a non-NULL pointer that
+** was not obtained from sqlite3_malloc() or sqlite3_realloc().
+**
+** ^(The sqlite3_realloc() interface attempts to resize a
+** prior memory allocation to be at least N bytes, where N is the
+** second parameter.  The memory allocation to be resized is the first
+** parameter.)^ ^ If the first parameter to sqlite3_realloc()
+** is a NULL pointer then its behavior is identical to calling
+** sqlite3_malloc(N) where N is the second parameter to sqlite3_realloc().
+** ^If the second parameter to sqlite3_realloc() is zero or
+** negative then the behavior is exactly the same as calling
+** sqlite3_free(P) where P is the first parameter to sqlite3_realloc().
+** ^sqlite3_realloc() returns a pointer to a memory allocation
+** of at least N bytes in size or NULL if sufficient memory is unavailable.
+** ^If M is the size of the prior allocation, then min(N,M) bytes
+** of the prior allocation are copied into the beginning of buffer returned
+** by sqlite3_realloc() and the prior allocation is freed.
+** ^If sqlite3_realloc() returns NULL, then the prior allocation
+** is not freed.
+**
+** ^The memory returned by sqlite3_malloc() and sqlite3_realloc()
+** is always aligned to at least an 8 byte boundary, or to a
+** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time
+** option is used.
+**
+** In SQLite version 3.5.0 and 3.5.1, it was possible to define
+** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
+** implementation of these routines to be omitted.  That capability
+** is no longer provided.  Only built-in memory allocators can be used.
+**
+** The Windows OS interface layer calls
+** the system malloc() and free() directly when converting
+** filenames between the UTF-8 encoding used by SQLite
+** and whatever filename encoding is used by the particular Windows
+** installation.  Memory allocation errors are detected, but
+** they are reported back as [SQLITE_CANTOPEN] or
+** [SQLITE_IOERR] rather than [SQLITE_NOMEM].
+**
+** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
+** must be either NULL or else pointers obtained from a prior
+** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
+** not yet been released.
+**
+** The application must not read or write any part of
+** a block of memory after it has been released using
+** [sqlite3_free()] or [sqlite3_realloc()].
+*/
+SQLITE_API void *sqlite3_malloc(int);
+SQLITE_API void *sqlite3_realloc(void*, int);
+SQLITE_API void sqlite3_free(void*);
+
+/*
+** CAPI3REF: Memory Allocator Statistics
+**
+** SQLite provides these two interfaces for reporting on the status
+** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
+** routines, which form the built-in memory allocation subsystem.
+**
+** ^The [sqlite3_memory_used()] routine returns the number of bytes
+** of memory currently outstanding (malloced but not freed).
+** ^The [sqlite3_memory_highwater()] routine returns the maximum
+** value of [sqlite3_memory_used()] since the high-water mark
+** was last reset.  ^The values returned by [sqlite3_memory_used()] and
+** [sqlite3_memory_highwater()] include any overhead
+** added by SQLite in its implementation of [sqlite3_malloc()],
+** but not overhead added by the any underlying system library
+** routines that [sqlite3_malloc()] may call.
+**
+** ^The memory high-water mark is reset to the current value of
+** [sqlite3_memory_used()] if and only if the parameter to
+** [sqlite3_memory_highwater()] is true.  ^The value returned
+** by [sqlite3_memory_highwater(1)] is the high-water mark
+** prior to the reset.
+*/
+SQLITE_API sqlite3_int64 sqlite3_memory_used(void);
+SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
+
+/*
+** CAPI3REF: Pseudo-Random Number Generator
+**
+** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
+** select random [ROWID | ROWIDs] when inserting new records into a table that
+** already uses the largest possible [ROWID].  The PRNG is also used for
+** the build-in random() and randomblob() SQL functions.  This interface allows
+** applications to access the same PRNG for other purposes.
+**
+** ^A call to this routine stores N bytes of randomness into buffer P.
+**
+** ^The first time this routine is invoked (either internally or by
+** the application) the PRNG is seeded using randomness obtained
+** from the xRandomness method of the default [sqlite3_vfs] object.
+** ^On all subsequent invocations, the pseudo-randomness is generated
+** internally and without recourse to the [sqlite3_vfs] xRandomness
+** method.
+*/
+SQLITE_API void sqlite3_randomness(int N, void *P);
+
+/*
+** CAPI3REF: Compile-Time Authorization Callbacks
+**
+** ^This routine registers a authorizer callback with a particular
+** [database connection], supplied in the first argument.
+** ^The authorizer callback is invoked as SQL statements are being compiled
+** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
+** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()].  ^At various
+** points during the compilation process, as logic is being created
+** to perform various actions, the authorizer callback is invoked to
+** see if those actions are allowed.  ^The authorizer callback should
+** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
+** specific action but allow the SQL statement to continue to be
+** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
+** rejected with an error.  ^If the authorizer callback returns
+** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
+** then the [sqlite3_prepare_v2()] or equivalent call that triggered
+** the authorizer will fail with an error message.
+**
+** When the callback returns [SQLITE_OK], that means the operation
+** requested is ok.  ^When the callback returns [SQLITE_DENY], the
+** [sqlite3_prepare_v2()] or equivalent call that triggered the
+** authorizer will fail with an error message explaining that
+** access is denied. 
+**
+** ^The first parameter to the authorizer callback is a copy of the third
+** parameter to the sqlite3_set_authorizer() interface. ^The second parameter
+** to the callback is an integer [SQLITE_COPY | action code] that specifies
+** the particular action to be authorized. ^The third through sixth parameters
+** to the callback are zero-terminated strings that contain additional
+** details about the action to be authorized.
+**
+** ^If the action code is [SQLITE_READ]
+** and the callback returns [SQLITE_IGNORE] then the
+** [prepared statement] statement is constructed to substitute
+** a NULL value in place of the table column that would have
+** been read if [SQLITE_OK] had been returned.  The [SQLITE_IGNORE]
+** return can be used to deny an untrusted user access to individual
+** columns of a table.
+** ^If the action code is [SQLITE_DELETE] and the callback returns
+** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
+** [truncate optimization] is disabled and all rows are deleted individually.
+**
+** An authorizer is used when [sqlite3_prepare | preparing]
+** SQL statements from an untrusted source, to ensure that the SQL statements
+** do not try to access data they are not allowed to see, or that they do not
+** try to execute malicious statements that damage the database.  For
+** example, an application may allow a user to enter arbitrary
+** SQL queries for evaluation by a database.  But the application does
+** not want the user to be able to make arbitrary changes to the
+** database.  An authorizer could then be put in place while the
+** user-entered SQL is being [sqlite3_prepare | prepared] that
+** disallows everything except [SELECT] statements.
+**
+** Applications that need to process SQL from untrusted sources
+** might also consider lowering resource limits using [sqlite3_limit()]
+** and limiting database size using the [max_page_count] [PRAGMA]
+** in addition to using an authorizer.
+**
+** ^(Only a single authorizer can be in place on a database connection
+** at a time.  Each call to sqlite3_set_authorizer overrides the
+** previous call.)^  ^Disable the authorizer by installing a NULL callback.
+** The authorizer is disabled by default.
+**
+** The authorizer callback must not do anything that will modify
+** the database connection that invoked the authorizer callback.
+** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
+** database connections for the meaning of "modify" in this paragraph.
+**
+** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the
+** statement might be re-prepared during [sqlite3_step()] due to a 
+** schema change.  Hence, the application should ensure that the
+** correct authorizer callback remains in place during the [sqlite3_step()].
+**
+** ^Note that the authorizer callback is invoked only during
+** [sqlite3_prepare()] or its variants.  Authorization is not
+** performed during statement evaluation in [sqlite3_step()], unless
+** as stated in the previous paragraph, sqlite3_step() invokes
+** sqlite3_prepare_v2() to reprepare a statement after a schema change.
+*/
+SQLITE_API int sqlite3_set_authorizer(
+  sqlite3*,
+  int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
+  void *pUserData
+);
+
+/*
+** CAPI3REF: Authorizer Return Codes
+**
+** The [sqlite3_set_authorizer | authorizer callback function] must
+** return either [SQLITE_OK] or one of these two constants in order
+** to signal SQLite whether or not the action is permitted.  See the
+** [sqlite3_set_authorizer | authorizer documentation] for additional
+** information.
+*/
+#define SQLITE_DENY   1   /* Abort the SQL statement with an error */
+#define SQLITE_IGNORE 2   /* Don't allow access, but don't generate an error */
+
+/*
+** CAPI3REF: Authorizer Action Codes
+**
+** The [sqlite3_set_authorizer()] interface registers a callback function
+** that is invoked to authorize certain SQL statement actions.  The
+** second parameter to the callback is an integer code that specifies
+** what action is being authorized.  These are the integer action codes that
+** the authorizer callback may be passed.
+**
+** These action code values signify what kind of operation is to be
+** authorized.  The 3rd and 4th parameters to the authorization
+** callback function will be parameters or NULL depending on which of these
+** codes is used as the second parameter.  ^(The 5th parameter to the
+** authorizer callback is the name of the database ("main", "temp",
+** etc.) if applicable.)^  ^The 6th parameter to the authorizer callback
+** is the name of the inner-most trigger or view that is responsible for
+** the access attempt or NULL if this access attempt is directly from
+** top-level SQL code.
+*/
+/******************************************* 3rd ************ 4th ***********/
+#define SQLITE_CREATE_INDEX          1   /* Index Name      Table Name      */
+#define SQLITE_CREATE_TABLE          2   /* Table Name      NULL            */
+#define SQLITE_CREATE_TEMP_INDEX     3   /* Index Name      Table Name      */
+#define SQLITE_CREATE_TEMP_TABLE     4   /* Table Name      NULL            */
+#define SQLITE_CREATE_TEMP_TRIGGER   5   /* Trigger Name    Table Name      */
+#define SQLITE_CREATE_TEMP_VIEW      6   /* View Name       NULL            */
+#define SQLITE_CREATE_TRIGGER        7   /* Trigger Name    Table Name      */
+#define SQLITE_CREATE_VIEW           8   /* View Name       NULL            */
+#define SQLITE_DELETE                9   /* Table Name      NULL            */
+#define SQLITE_DROP_INDEX           10   /* Index Name      Table Name      */
+#define SQLITE_DROP_TABLE           11   /* Table Name      NULL            */
+#define SQLITE_DROP_TEMP_INDEX      12   /* Index Name      Table Name      */
+#define SQLITE_DROP_TEMP_TABLE      13   /* Table Name      NULL            */
+#define SQLITE_DROP_TEMP_TRIGGER    14   /* Trigger Name    Table Name      */
+#define SQLITE_DROP_TEMP_VIEW       15   /* View Name       NULL            */
+#define SQLITE_DROP_TRIGGER         16   /* Trigger Name    Table Name      */
+#define SQLITE_DROP_VIEW            17   /* View Name       NULL            */
+#define SQLITE_INSERT               18   /* Table Name      NULL            */
+#define SQLITE_PRAGMA               19   /* Pragma Name     1st arg or NULL */
+#define SQLITE_READ                 20   /* Table Name      Column Name     */
+#define SQLITE_SELECT               21   /* NULL            NULL            */
+#define SQLITE_TRANSACTION          22   /* Operation       NULL            */
+#define SQLITE_UPDATE               23   /* Table Name      Column Name     */
+#define SQLITE_ATTACH               24   /* Filename        NULL            */
+#define SQLITE_DETACH               25   /* Database Name   NULL            */
+#define SQLITE_ALTER_TABLE          26   /* Database Name   Table Name      */
+#define SQLITE_REINDEX              27   /* Index Name      NULL            */
+#define SQLITE_ANALYZE              28   /* Table Name      NULL            */
+#define SQLITE_CREATE_VTABLE        29   /* Table Name      Module Name     */
+#define SQLITE_DROP_VTABLE          30   /* Table Name      Module Name     */
+#define SQLITE_FUNCTION             31   /* NULL            Function Name   */
+#define SQLITE_SAVEPOINT            32   /* Operation       Savepoint Name  */
+#define SQLITE_COPY                  0   /* No longer used */
+
+/*
+** CAPI3REF: Tracing And Profiling Functions
+**
+** These routines register callback functions that can be used for
+** tracing and profiling the execution of SQL statements.
+**
+** ^The callback function registered by sqlite3_trace() is invoked at
+** various times when an SQL statement is being run by [sqlite3_step()].
+** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the
+** SQL statement text as the statement first begins executing.
+** ^(Additional sqlite3_trace() callbacks might occur
+** as each triggered subprogram is entered.  The callbacks for triggers
+** contain a UTF-8 SQL comment that identifies the trigger.)^
+**
+** ^The callback function registered by sqlite3_profile() is invoked
+** as each SQL statement finishes.  ^The profile callback contains
+** the original statement text and an estimate of wall-clock time
+** of how long that statement took to run.  ^The profile callback
+** time is in units of nanoseconds, however the current implementation
+** is only capable of millisecond resolution so the six least significant
+** digits in the time are meaningless.  Future versions of SQLite
+** might provide greater resolution on the profiler callback.  The
+** sqlite3_profile() function is considered experimental and is
+** subject to change in future versions of SQLite.
+*/
+SQLITE_API void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
+SQLITE_API SQLITE_EXPERIMENTAL void *sqlite3_profile(sqlite3*,
+   void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
+
+/*
+** CAPI3REF: Query Progress Callbacks
+**
+** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback
+** function X to be invoked periodically during long running calls to
+** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for
+** database connection D.  An example use for this
+** interface is to keep a GUI updated during a large query.
+**
+** ^The parameter P is passed through as the only parameter to the 
+** callback function X.  ^The parameter N is the number of 
+** [virtual machine instructions] that are evaluated between successive
+** invocations of the callback X.
+**
+** ^Only a single progress handler may be defined at one time per
+** [database connection]; setting a new progress handler cancels the
+** old one.  ^Setting parameter X to NULL disables the progress handler.
+** ^The progress handler is also disabled by setting N to a value less
+** than 1.
+**
+** ^If the progress callback returns non-zero, the operation is
+** interrupted.  This feature can be used to implement a
+** "Cancel" button on a GUI progress dialog box.
+**
+** The progress handler callback must not do anything that will modify
+** the database connection that invoked the progress handler.
+** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
+** database connections for the meaning of "modify" in this paragraph.
+**
+*/
+SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
+
+/*
+** CAPI3REF: Opening A New Database Connection
+**
+** ^These routines open an SQLite database file whose name is given by the
+** filename argument. ^The filename argument is interpreted as UTF-8 for
+** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
+** order for sqlite3_open16(). ^(A [database connection] handle is usually
+** returned in *ppDb, even if an error occurs.  The only exception is that
+** if SQLite is unable to allocate memory to hold the [sqlite3] object,
+** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
+** object.)^ ^(If the database is opened (and/or created) successfully, then
+** [SQLITE_OK] is returned.  Otherwise an [error code] is returned.)^ ^The
+** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
+** an English language description of the error following a failure of any
+** of the sqlite3_open() routines.
+**
+** ^The default encoding for the database will be UTF-8 if
+** sqlite3_open() or sqlite3_open_v2() is called and
+** UTF-16 in the native byte order if sqlite3_open16() is used.
+**
+** Whether or not an error occurs when it is opened, resources
+** associated with the [database connection] handle should be released by
+** passing it to [sqlite3_close()] when it is no longer required.
+**
+** The sqlite3_open_v2() interface works like sqlite3_open()
+** except that it accepts two additional parameters for additional control
+** over the new database connection.  ^(The flags parameter to
+** sqlite3_open_v2() can take one of
+** the following three values, optionally combined with the 
+** [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], [SQLITE_OPEN_SHAREDCACHE],
+** and/or [SQLITE_OPEN_PRIVATECACHE] flags:)^
+**
+** <dl>
+** ^(<dt>[SQLITE_OPEN_READONLY]</dt>
+** <dd>The database is opened in read-only mode.  If the database does not
+** already exist, an error is returned.</dd>)^
+**
+** ^(<dt>[SQLITE_OPEN_READWRITE]</dt>
+** <dd>The database is opened for reading and writing if possible, or reading
+** only if the file is write protected by the operating system.  In either
+** case the database must already exist, otherwise an error is returned.</dd>)^
+**
+** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
+** <dd>The database is opened for reading and writing, and is creates it if
+** it does not already exist. This is the behavior that is always used for
+** sqlite3_open() and sqlite3_open16().</dd>)^
+** </dl>
+**
+** If the 3rd parameter to sqlite3_open_v2() is not one of the
+** combinations shown above or one of the combinations shown above combined
+** with the [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX],
+** [SQLITE_OPEN_SHAREDCACHE] and/or [SQLITE_OPEN_PRIVATECACHE] flags,
+** then the behavior is undefined.
+**
+** ^If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection
+** opens in the multi-thread [threading mode] as long as the single-thread
+** mode has not been set at compile-time or start-time.  ^If the
+** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens
+** in the serialized [threading mode] unless single-thread was
+** previously selected at compile-time or start-time.
+** ^The [SQLITE_OPEN_SHAREDCACHE] flag causes the database connection to be
+** eligible to use [shared cache mode], regardless of whether or not shared
+** cache is enabled using [sqlite3_enable_shared_cache()].  ^The
+** [SQLITE_OPEN_PRIVATECACHE] flag causes the database connection to not
+** participate in [shared cache mode] even if it is enabled.
+**
+** ^If the filename is ":memory:", then a private, temporary in-memory database
+** is created for the connection.  ^This in-memory database will vanish when
+** the database connection is closed.  Future versions of SQLite might
+** make use of additional special filenames that begin with the ":" character.
+** It is recommended that when a database filename actually does begin with
+** a ":" character you should prefix the filename with a pathname such as
+** "./" to avoid ambiguity.
+**
+** ^If the filename is an empty string, then a private, temporary
+** on-disk database will be created.  ^This private database will be
+** automatically deleted as soon as the database connection is closed.
+**
+** ^The fourth parameter to sqlite3_open_v2() is the name of the
+** [sqlite3_vfs] object that defines the operating system interface that
+** the new database connection should use.  ^If the fourth parameter is
+** a NULL pointer then the default [sqlite3_vfs] object is used.
+**
+** <b>Note to Windows users:</b>  The encoding used for the filename argument
+** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
+** codepage is currently defined.  Filenames containing international
+** characters must be converted to UTF-8 prior to passing them into
+** sqlite3_open() or sqlite3_open_v2().
+*/
+SQLITE_API int sqlite3_open(
+  const char *filename,   /* Database filename (UTF-8) */
+  sqlite3 **ppDb          /* OUT: SQLite db handle */
+);
+SQLITE_API int sqlite3_open16(
+  const void *filename,   /* Database filename (UTF-16) */
+  sqlite3 **ppDb          /* OUT: SQLite db handle */
+);
+SQLITE_API int sqlite3_open_v2(
+  const char *filename,   /* Database filename (UTF-8) */
+  sqlite3 **ppDb,         /* OUT: SQLite db handle */
+  int flags,              /* Flags */
+  const char *zVfs        /* Name of VFS module to use */
+);
+
+/*
+** CAPI3REF: Error Codes And Messages
+**
+** ^The sqlite3_errcode() interface returns the numeric [result code] or
+** [extended result code] for the most recent failed sqlite3_* API call
+** associated with a [database connection]. If a prior API call failed
+** but the most recent API call succeeded, the return value from
+** sqlite3_errcode() is undefined.  ^The sqlite3_extended_errcode()
+** interface is the same except that it always returns the 
+** [extended result code] even when extended result codes are
+** disabled.
+**
+** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
+** text that describes the error, as either UTF-8 or UTF-16 respectively.
+** ^(Memory to hold the error message string is managed internally.
+** The application does not need to worry about freeing the result.
+** However, the error string might be overwritten or deallocated by
+** subsequent calls to other SQLite interface functions.)^
+**
+** When the serialized [threading mode] is in use, it might be the
+** case that a second error occurs on a separate thread in between
+** the time of the first error and the call to these interfaces.
+** When that happens, the second error will be reported since these
+** interfaces always report the most recent result.  To avoid
+** this, each thread can obtain exclusive use of the [database connection] D
+** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
+** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
+** all calls to the interfaces listed here are completed.
+**
+** If an interface fails with SQLITE_MISUSE, that means the interface
+** was invoked incorrectly by the application.  In that case, the
+** error code and message may or may not be set.
+*/
+SQLITE_API int sqlite3_errcode(sqlite3 *db);
+SQLITE_API int sqlite3_extended_errcode(sqlite3 *db);
+SQLITE_API const char *sqlite3_errmsg(sqlite3*);
+SQLITE_API const void *sqlite3_errmsg16(sqlite3*);
+
+/*
+** CAPI3REF: SQL Statement Object
+** KEYWORDS: {prepared statement} {prepared statements}
+**
+** An instance of this object represents a single SQL statement.
+** This object is variously known as a "prepared statement" or a
+** "compiled SQL statement" or simply as a "statement".
+**
+** The life of a statement object goes something like this:
+**
+** <ol>
+** <li> Create the object using [sqlite3_prepare_v2()] or a related
+**      function.
+** <li> Bind values to [host parameters] using the sqlite3_bind_*()
+**      interfaces.
+** <li> Run the SQL by calling [sqlite3_step()] one or more times.
+** <li> Reset the statement using [sqlite3_reset()] then go back
+**      to step 2.  Do this zero or more times.
+** <li> Destroy the object using [sqlite3_finalize()].
+** </ol>
+**
+** Refer to documentation on individual methods above for additional
+** information.
+*/
+typedef struct sqlite3_stmt sqlite3_stmt;
+
+/*
+** CAPI3REF: Run-time Limits
+**
+** ^(This interface allows the size of various constructs to be limited
+** on a connection by connection basis.  The first parameter is the
+** [database connection] whose limit is to be set or queried.  The
+** second parameter is one of the [limit categories] that define a
+** class of constructs to be size limited.  The third parameter is the
+** new limit for that construct.)^
+**
+** ^If the new limit is a negative number, the limit is unchanged.
+** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a 
+** [limits | hard upper bound]
+** set at compile-time by a C preprocessor macro called
+** [limits | SQLITE_MAX_<i>NAME</i>].
+** (The "_LIMIT_" in the name is changed to "_MAX_".))^
+** ^Attempts to increase a limit above its hard upper bound are
+** silently truncated to the hard upper bound.
+**
+** ^Regardless of whether or not the limit was changed, the 
+** [sqlite3_limit()] interface returns the prior value of the limit.
+** ^Hence, to find the current value of a limit without changing it,
+** simply invoke this interface with the third parameter set to -1.
+**
+** Run-time limits are intended for use in applications that manage
+** both their own internal database and also databases that are controlled
+** by untrusted external sources.  An example application might be a
+** web browser that has its own databases for storing history and
+** separate databases controlled by JavaScript applications downloaded
+** off the Internet.  The internal databases can be given the
+** large, default limits.  Databases managed by external sources can
+** be given much smaller limits designed to prevent a denial of service
+** attack.  Developers might also want to use the [sqlite3_set_authorizer()]
+** interface to further control untrusted SQL.  The size of the database
+** created by an untrusted script can be contained using the
+** [max_page_count] [PRAGMA].
+**
+** New run-time limit categories may be added in future releases.
+*/
+SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);
+
+/*
+** CAPI3REF: Run-Time Limit Categories
+** KEYWORDS: {limit category} {*limit categories}
+**
+** These constants define various performance limits
+** that can be lowered at run-time using [sqlite3_limit()].
+** The synopsis of the meanings of the various limits is shown below.
+** Additional information is available at [limits | Limits in SQLite].
+**
+** <dl>
+** ^(<dt>SQLITE_LIMIT_LENGTH</dt>
+** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^
+**
+** ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt>
+** <dd>The maximum length of an SQL statement, in bytes.</dd>)^
+**
+** ^(<dt>SQLITE_LIMIT_COLUMN</dt>
+** <dd>The maximum number of columns in a table definition or in the
+** result set of a [SELECT] or the maximum number of columns in an index
+** or in an ORDER BY or GROUP BY clause.</dd>)^
+**
+** ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
+** <dd>The maximum depth of the parse tree on any expression.</dd>)^
+**
+** ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
+** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^
+**
+** ^(<dt>SQLITE_LIMIT_VDBE_OP</dt>
+** <dd>The maximum number of instructions in a virtual machine program
+** used to implement an SQL statement.  This limit is not currently
+** enforced, though that might be added in some future release of
+** SQLite.</dd>)^
+**
+** ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
+** <dd>The maximum number of arguments on a function.</dd>)^
+**
+** ^(<dt>SQLITE_LIMIT_ATTACHED</dt>
+** <dd>The maximum number of [ATTACH | attached databases].)^</dd>
+**
+** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
+** <dd>The maximum length of the pattern argument to the [LIKE] or
+** [GLOB] operators.</dd>)^
+**
+** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
+** <dd>The maximum index number of any [parameter] in an SQL statement.)^
+**
+** ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
+** <dd>The maximum depth of recursion for triggers.</dd>)^
+** </dl>
+*/
+#define SQLITE_LIMIT_LENGTH                    0
+#define SQLITE_LIMIT_SQL_LENGTH                1
+#define SQLITE_LIMIT_COLUMN                    2
+#define SQLITE_LIMIT_EXPR_DEPTH                3
+#define SQLITE_LIMIT_COMPOUND_SELECT           4
+#define SQLITE_LIMIT_VDBE_OP                   5
+#define SQLITE_LIMIT_FUNCTION_ARG              6
+#define SQLITE_LIMIT_ATTACHED                  7
+#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH       8
+#define SQLITE_LIMIT_VARIABLE_NUMBER           9
+#define SQLITE_LIMIT_TRIGGER_DEPTH            10
+
+/*
+** CAPI3REF: Compiling An SQL Statement
+** KEYWORDS: {SQL statement compiler}
+**
+** To execute an SQL query, it must first be compiled into a byte-code
+** program using one of these routines.
+**
+** The first argument, "db", is a [database connection] obtained from a
+** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
+** [sqlite3_open16()].  The database connection must not have been closed.
+**
+** The second argument, "zSql", is the statement to be compiled, encoded
+** as either UTF-8 or UTF-16.  The sqlite3_prepare() and sqlite3_prepare_v2()
+** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2()
+** use UTF-16.
+**
+** ^If the nByte argument is less than zero, then zSql is read up to the
+** first zero terminator. ^If nByte is non-negative, then it is the maximum
+** number of  bytes read from zSql.  ^When nByte is non-negative, the
+** zSql string ends at either the first '\000' or '\u0000' character or
+** the nByte-th byte, whichever comes first. If the caller knows
+** that the supplied string is nul-terminated, then there is a small
+** performance advantage to be gained by passing an nByte parameter that
+** is equal to the number of bytes in the input string <i>including</i>
+** the nul-terminator bytes.
+**
+** ^If pzTail is not NULL then *pzTail is made to point to the first byte
+** past the end of the first SQL statement in zSql.  These routines only
+** compile the first statement in zSql, so *pzTail is left pointing to
+** what remains uncompiled.
+**
+** ^*ppStmt is left pointing to a compiled [prepared statement] that can be
+** executed using [sqlite3_step()].  ^If there is an error, *ppStmt is set
+** to NULL.  ^If the input text contains no SQL (if the input is an empty
+** string or a comment) then *ppStmt is set to NULL.
+** The calling procedure is responsible for deleting the compiled
+** SQL statement using [sqlite3_finalize()] after it has finished with it.
+** ppStmt may not be NULL.
+**
+** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK];
+** otherwise an [error code] is returned.
+**
+** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are
+** recommended for all new programs. The two older interfaces are retained
+** for backwards compatibility, but their use is discouraged.
+** ^In the "v2" interfaces, the prepared statement
+** that is returned (the [sqlite3_stmt] object) contains a copy of the
+** original SQL text. This causes the [sqlite3_step()] interface to
+** behave differently in three ways:
+**
+** <ol>
+** <li>
+** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
+** always used to do, [sqlite3_step()] will automatically recompile the SQL
+** statement and try to run it again.
+** </li>
+**
+** <li>
+** ^When an error occurs, [sqlite3_step()] will return one of the detailed
+** [error codes] or [extended error codes].  ^The legacy behavior was that
+** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
+** and the application would have to make a second call to [sqlite3_reset()]
+** in order to find the underlying cause of the problem. With the "v2" prepare
+** interfaces, the underlying reason for the error is returned immediately.
+** </li>
+**
+** <li>
+** ^If the specific value bound to [parameter | host parameter] in the 
+** WHERE clause might influence the choice of query plan for a statement,
+** then the statement will be automatically recompiled, as if there had been 
+** a schema change, on the first  [sqlite3_step()] call following any change
+** to the [sqlite3_bind_text | bindings] of that [parameter]. 
+** ^The specific value of WHERE-clause [parameter] might influence the 
+** choice of query plan if the parameter is the left-hand side of a [LIKE]
+** or [GLOB] operator or if the parameter is compared to an indexed column
+** and the [SQLITE_ENABLE_STAT2] compile-time option is enabled.
+** the 
+** </li>
+** </ol>
+*/
+SQLITE_API int sqlite3_prepare(
+  sqlite3 *db,            /* Database handle */
+  const char *zSql,       /* SQL statement, UTF-8 encoded */
+  int nByte,              /* Maximum length of zSql in bytes. */
+  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
+  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
+);
+SQLITE_API int sqlite3_prepare_v2(
+  sqlite3 *db,            /* Database handle */
+  const char *zSql,       /* SQL statement, UTF-8 encoded */
+  int nByte,              /* Maximum length of zSql in bytes. */
+  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
+  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
+);
+SQLITE_API int sqlite3_prepare16(
+  sqlite3 *db,            /* Database handle */
+  const void *zSql,       /* SQL statement, UTF-16 encoded */
+  int nByte,              /* Maximum length of zSql in bytes. */
+  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
+  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
+);
+SQLITE_API int sqlite3_prepare16_v2(
+  sqlite3 *db,            /* Database handle */
+  const void *zSql,       /* SQL statement, UTF-16 encoded */
+  int nByte,              /* Maximum length of zSql in bytes. */
+  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
+  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
+);
+
+/*
+** CAPI3REF: Retrieving Statement SQL
+**
+** ^This interface can be used to retrieve a saved copy of the original
+** SQL text used to create a [prepared statement] if that statement was
+** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].
+*/
+SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt);
+
+/*
+** CAPI3REF: Dynamically Typed Value Object
+** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
+**
+** SQLite uses the sqlite3_value object to represent all values
+** that can be stored in a database table. SQLite uses dynamic typing
+** for the values it stores.  ^Values stored in sqlite3_value objects
+** can be integers, floating point values, strings, BLOBs, or NULL.
+**
+** An sqlite3_value object may be either "protected" or "unprotected".
+** Some interfaces require a protected sqlite3_value.  Other interfaces
+** will accept either a protected or an unprotected sqlite3_value.
+** Every interface that accepts sqlite3_value arguments specifies
+** whether or not it requires a protected sqlite3_value.
+**
+** The terms "protected" and "unprotected" refer to whether or not
+** a mutex is held.  A internal mutex is held for a protected
+** sqlite3_value object but no mutex is held for an unprotected
+** sqlite3_value object.  If SQLite is compiled to be single-threaded
+** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
+** or if SQLite is run in one of reduced mutex modes 
+** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
+** then there is no distinction between protected and unprotected
+** sqlite3_value objects and they can be used interchangeably.  However,
+** for maximum code portability it is recommended that applications
+** still make the distinction between protected and unprotected
+** sqlite3_value objects even when not strictly required.
+**
+** ^The sqlite3_value objects that are passed as parameters into the
+** implementation of [application-defined SQL functions] are protected.
+** ^The sqlite3_value object returned by
+** [sqlite3_column_value()] is unprotected.
+** Unprotected sqlite3_value objects may only be used with
+** [sqlite3_result_value()] and [sqlite3_bind_value()].
+** The [sqlite3_value_blob | sqlite3_value_type()] family of
+** interfaces require protected sqlite3_value objects.
+*/
+typedef struct Mem sqlite3_value;
+
+/*
+** CAPI3REF: SQL Function Context Object
+**
+** The context in which an SQL function executes is stored in an
+** sqlite3_context object.  ^A pointer to an sqlite3_context object
+** is always first parameter to [application-defined SQL functions].
+** The application-defined SQL function implementation will pass this
+** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
+** [sqlite3_aggregate_context()], [sqlite3_user_data()],
+** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
+** and/or [sqlite3_set_auxdata()].
+*/
+typedef struct sqlite3_context sqlite3_context;
+
+/*
+** CAPI3REF: Binding Values To Prepared Statements
+** KEYWORDS: {host parameter} {host parameters} {host parameter name}
+** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
+**
+** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,
+** literals may be replaced by a [parameter] that matches one of following
+** templates:
+**
+** <ul>
+** <li>  ?
+** <li>  ?NNN
+** <li>  :VVV
+** <li>  @VVV
+** <li>  $VVV
+** </ul>
+**
+** In the templates above, NNN represents an integer literal,
+** and VVV represents an alphanumeric identifier.)^  ^The values of these
+** parameters (also called "host parameter names" or "SQL parameters")
+** can be set using the sqlite3_bind_*() routines defined here.
+**
+** ^The first argument to the sqlite3_bind_*() routines is always
+** a pointer to the [sqlite3_stmt] object returned from
+** [sqlite3_prepare_v2()] or its variants.
+**
+** ^The second argument is the index of the SQL parameter to be set.
+** ^The leftmost SQL parameter has an index of 1.  ^When the same named
+** SQL parameter is used more than once, second and subsequent
+** occurrences have the same index as the first occurrence.
+** ^The index for named parameters can be looked up using the
+** [sqlite3_bind_parameter_index()] API if desired.  ^The index
+** for "?NNN" parameters is the value of NNN.
+** ^The NNN value must be between 1 and the [sqlite3_limit()]
+** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
+**
+** ^The third argument is the value to bind to the parameter.
+**
+** ^(In those routines that have a fourth argument, its value is the
+** number of bytes in the parameter.  To be clear: the value is the
+** number of <u>bytes</u> in the value, not the number of characters.)^
+** ^If the fourth parameter is negative, the length of the string is
+** the number of bytes up to the first zero terminator.
+**
+** ^The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and
+** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or
+** string after SQLite has finished with it. ^If the fifth argument is
+** the special value [SQLITE_STATIC], then SQLite assumes that the
+** information is in static, unmanaged space and does not need to be freed.
+** ^If the fifth argument has the value [SQLITE_TRANSIENT], then
+** SQLite makes its own private copy of the data immediately, before
+** the sqlite3_bind_*() routine returns.
+**
+** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
+** is filled with zeroes.  ^A zeroblob uses a fixed amount of memory
+** (just an integer to hold its size) while it is being processed.
+** Zeroblobs are intended to serve as placeholders for BLOBs whose
+** content is later written using
+** [sqlite3_blob_open | incremental BLOB I/O] routines.
+** ^A negative value for the zeroblob results in a zero-length BLOB.
+**
+** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer
+** for the [prepared statement] or with a prepared statement for which
+** [sqlite3_step()] has been called more recently than [sqlite3_reset()],
+** then the call will return [SQLITE_MISUSE].  If any sqlite3_bind_()
+** routine is passed a [prepared statement] that has been finalized, the
+** result is undefined and probably harmful.
+**
+** ^Bindings are not cleared by the [sqlite3_reset()] routine.
+** ^Unbound parameters are interpreted as NULL.
+**
+** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an
+** [error code] if anything goes wrong.
+** ^[SQLITE_RANGE] is returned if the parameter
+** index is out of range.  ^[SQLITE_NOMEM] is returned if malloc() fails.
+**
+** See also: [sqlite3_bind_parameter_count()],
+** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
+*/
+SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
+SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double);
+SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int);
+SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
+SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int);
+SQLITE_API int sqlite3_bind_text(sqlite3_stmt*, int, const char*, int n, void(*)(void*));
+SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
+SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
+SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
+
+/*
+** CAPI3REF: Number Of SQL Parameters
+**
+** ^This routine can be used to find the number of [SQL parameters]
+** in a [prepared statement].  SQL parameters are tokens of the
+** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
+** placeholders for values that are [sqlite3_bind_blob | bound]
+** to the parameters at a later time.
+**
+** ^(This routine actually returns the index of the largest (rightmost)
+** parameter. For all forms except ?NNN, this will correspond to the
+** number of unique parameters.  If parameters of the ?NNN form are used,
+** there may be gaps in the list.)^
+**
+** See also: [sqlite3_bind_blob|sqlite3_bind()],
+** [sqlite3_bind_parameter_name()], and
+** [sqlite3_bind_parameter_index()].
+*/
+SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*);
+
+/*
+** CAPI3REF: Name Of A Host Parameter
+**
+** ^The sqlite3_bind_parameter_name(P,N) interface returns
+** the name of the N-th [SQL parameter] in the [prepared statement] P.
+** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
+** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
+** respectively.
+** In other words, the initial ":" or "$" or "@" or "?"
+** is included as part of the name.)^
+** ^Parameters of the form "?" without a following integer have no name
+** and are referred to as "nameless" or "anonymous parameters".
+**
+** ^The first host parameter has an index of 1, not 0.
+**
+** ^If the value N is out of range or if the N-th parameter is
+** nameless, then NULL is returned.  ^The returned string is
+** always in UTF-8 encoding even if the named parameter was
+** originally specified as UTF-16 in [sqlite3_prepare16()] or
+** [sqlite3_prepare16_v2()].
+**
+** See also: [sqlite3_bind_blob|sqlite3_bind()],
+** [sqlite3_bind_parameter_count()], and
+** [sqlite3_bind_parameter_index()].
+*/
+SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
+
+/*
+** CAPI3REF: Index Of A Parameter With A Given Name
+**
+** ^Return the index of an SQL parameter given its name.  ^The
+** index value returned is suitable for use as the second
+** parameter to [sqlite3_bind_blob|sqlite3_bind()].  ^A zero
+** is returned if no matching parameter is found.  ^The parameter
+** name must be given in UTF-8 even if the original statement
+** was prepared from UTF-16 text using [sqlite3_prepare16_v2()].
+**
+** See also: [sqlite3_bind_blob|sqlite3_bind()],
+** [sqlite3_bind_parameter_count()], and
+** [sqlite3_bind_parameter_index()].
+*/
+SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
+
+/*
+** CAPI3REF: Reset All Bindings On A Prepared Statement
+**
+** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset
+** the [sqlite3_bind_blob | bindings] on a [prepared statement].
+** ^Use this routine to reset all host parameters to NULL.
+*/
+SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*);
+
+/*
+** CAPI3REF: Number Of Columns In A Result Set
+**
+** ^Return the number of columns in the result set returned by the
+** [prepared statement]. ^This routine returns 0 if pStmt is an SQL
+** statement that does not return data (for example an [UPDATE]).
+**
+** See also: [sqlite3_data_count()]
+*/
+SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);
+
+/*
+** CAPI3REF: Column Names In A Result Set
+**
+** ^These routines return the name assigned to a particular column
+** in the result set of a [SELECT] statement.  ^The sqlite3_column_name()
+** interface returns a pointer to a zero-terminated UTF-8 string
+** and sqlite3_column_name16() returns a pointer to a zero-terminated
+** UTF-16 string.  ^The first parameter is the [prepared statement]
+** that implements the [SELECT] statement. ^The second parameter is the
+** column number.  ^The leftmost column is number 0.
+**
+** ^The returned string pointer is valid until either the [prepared statement]
+** is destroyed by [sqlite3_finalize()] or until the next call to
+** sqlite3_column_name() or sqlite3_column_name16() on the same column.
+**
+** ^If sqlite3_malloc() fails during the processing of either routine
+** (for example during a conversion from UTF-8 to UTF-16) then a
+** NULL pointer is returned.
+**
+** ^The name of a result column is the value of the "AS" clause for
+** that column, if there is an AS clause.  If there is no AS clause
+** then the name of the column is unspecified and may change from
+** one release of SQLite to the next.
+*/
+SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N);
+SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N);
+
+/*
+** CAPI3REF: Source Of Data In A Query Result
+**
+** ^These routines provide a means to determine the database, table, and
+** table column that is the origin of a particular result column in
+** [SELECT] statement.
+** ^The name of the database or table or column can be returned as
+** either a UTF-8 or UTF-16 string.  ^The _database_ routines return
+** the database name, the _table_ routines return the table name, and
+** the origin_ routines return the column name.
+** ^The returned string is valid until the [prepared statement] is destroyed
+** using [sqlite3_finalize()] or until the same information is requested
+** again in a different encoding.
+**
+** ^The names returned are the original un-aliased names of the
+** database, table, and column.
+**
+** ^The first argument to these interfaces is a [prepared statement].
+** ^These functions return information about the Nth result column returned by
+** the statement, where N is the second function argument.
+** ^The left-most column is column 0 for these routines.
+**
+** ^If the Nth column returned by the statement is an expression or
+** subquery and is not a column value, then all of these functions return
+** NULL.  ^These routine might also return NULL if a memory allocation error
+** occurs.  ^Otherwise, they return the name of the attached database, table,
+** or column that query result column was extracted from.
+**
+** ^As with all other SQLite APIs, those whose names end with "16" return
+** UTF-16 encoded strings and the other functions return UTF-8.
+**
+** ^These APIs are only available if the library was compiled with the
+** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol.
+**
+** If two or more threads call one or more of these routines against the same
+** prepared statement and column at the same time then the results are
+** undefined.
+**
+** If two or more threads call one or more
+** [sqlite3_column_database_name | column metadata interfaces]
+** for the same [prepared statement] and result column
+** at the same time then the results are undefined.
+*/
+SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int);
+SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
+SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int);
+SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
+SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
+SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
+
+/*
+** CAPI3REF: Declared Datatype Of A Query Result
+**
+** ^(The first parameter is a [prepared statement].
+** If this statement is a [SELECT] statement and the Nth column of the
+** returned result set of that [SELECT] is a table column (not an
+** expression or subquery) then the declared type of the table
+** column is returned.)^  ^If the Nth column of the result set is an
+** expression or subquery, then a NULL pointer is returned.
+** ^The returned string is always UTF-8 encoded.
+**
+** ^(For example, given the database schema:
+**
+** CREATE TABLE t1(c1 VARIANT);
+**
+** and the following statement to be compiled:
+**
+** SELECT c1 + 1, c1 FROM t1;
+**
+** this routine would return the string "VARIANT" for the second result
+** column (i==1), and a NULL pointer for the first result column (i==0).)^
+**
+** ^SQLite uses dynamic run-time typing.  ^So just because a column
+** is declared to contain a particular type does not mean that the
+** data stored in that column is of the declared type.  SQLite is
+** strongly typed, but the typing is dynamic not static.  ^Type
+** is associated with individual values, not with the containers
+** used to hold those values.
+*/
+SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int);
+SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
+
+/*
+** CAPI3REF: Evaluate An SQL Statement
+**
+** After a [prepared statement] has been prepared using either
+** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy
+** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
+** must be called one or more times to evaluate the statement.
+**
+** The details of the behavior of the sqlite3_step() interface depend
+** on whether the statement was prepared using the newer "v2" interface
+** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy
+** interface [sqlite3_prepare()] and [sqlite3_prepare16()].  The use of the
+** new "v2" interface is recommended for new applications but the legacy
+** interface will continue to be supported.
+**
+** ^In the legacy interface, the return value will be either [SQLITE_BUSY],
+** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
+** ^With the "v2" interface, any of the other [result codes] or
+** [extended result codes] might be returned as well.
+**
+** ^[SQLITE_BUSY] means that the database engine was unable to acquire the
+** database locks it needs to do its job.  ^If the statement is a [COMMIT]
+** or occurs outside of an explicit transaction, then you can retry the
+** statement.  If the statement is not a [COMMIT] and occurs within a
+** explicit transaction then you should rollback the transaction before
+** continuing.
+**
+** ^[SQLITE_DONE] means that the statement has finished executing
+** successfully.  sqlite3_step() should not be called again on this virtual
+** machine without first calling [sqlite3_reset()] to reset the virtual
+** machine back to its initial state.
+**
+** ^If the SQL statement being executed returns any data, then [SQLITE_ROW]
+** is returned each time a new row of data is ready for processing by the
+** caller. The values may be accessed using the [column access functions].
+** sqlite3_step() is called again to retrieve the next row of data.
+**
+** ^[SQLITE_ERROR] means that a run-time error (such as a constraint
+** violation) has occurred.  sqlite3_step() should not be called again on
+** the VM. More information may be found by calling [sqlite3_errmsg()].
+** ^With the legacy interface, a more specific error code (for example,
+** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
+** can be obtained by calling [sqlite3_reset()] on the
+** [prepared statement].  ^In the "v2" interface,
+** the more specific error code is returned directly by sqlite3_step().
+**
+** [SQLITE_MISUSE] means that the this routine was called inappropriately.
+** Perhaps it was called on a [prepared statement] that has
+** already been [sqlite3_finalize | finalized] or on one that had
+** previously returned [SQLITE_ERROR] or [SQLITE_DONE].  Or it could
+** be the case that the same database connection is being used by two or
+** more threads at the same moment in time.
+**
+** For all versions of SQLite up to and including 3.6.23.1, it was required
+** after sqlite3_step() returned anything other than [SQLITE_ROW] that
+** [sqlite3_reset()] be called before any subsequent invocation of
+** sqlite3_step().  Failure to invoke [sqlite3_reset()] in this way would
+** result in an [SQLITE_MISUSE] return from sqlite3_step().  But after
+** version 3.6.23.1, sqlite3_step() began calling [sqlite3_reset()] 
+** automatically in this circumstance rather than returning [SQLITE_MISUSE].  
+**
+** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
+** API always returns a generic error code, [SQLITE_ERROR], following any
+** error other than [SQLITE_BUSY] and [SQLITE_MISUSE].  You must call
+** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
+** specific [error codes] that better describes the error.
+** We admit that this is a goofy design.  The problem has been fixed
+** with the "v2" interface.  If you prepare all of your SQL statements
+** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead
+** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
+** then the more specific [error codes] are returned directly
+** by sqlite3_step().  The use of the "v2" interface is recommended.
+*/
+SQLITE_API int sqlite3_step(sqlite3_stmt*);
+
+/*
+** CAPI3REF: Number of columns in a result set
+**
+** ^The sqlite3_data_count(P) interface returns the number of columns in the
+** current row of the result set of [prepared statement] P.
+** ^If prepared statement P does not have results ready to return
+** (via calls to the [sqlite3_column_int | sqlite3_column_*()] of
+** interfaces) then sqlite3_data_count(P) returns 0.
+** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.
+**
+** See also: [sqlite3_column_count()]
+*/
+SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
+
+/*
+** CAPI3REF: Fundamental Datatypes
+** KEYWORDS: SQLITE_TEXT
+**
+** ^(Every value in SQLite has one of five fundamental datatypes:
+**
+** <ul>
+** <li> 64-bit signed integer
+** <li> 64-bit IEEE floating point number
+** <li> string
+** <li> BLOB
+** <li> NULL
+** </ul>)^
+**
+** These constants are codes for each of those types.
+**
+** Note that the SQLITE_TEXT constant was also used in SQLite version 2
+** for a completely different meaning.  Software that links against both
+** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
+** SQLITE_TEXT.
+*/
+#define SQLITE_INTEGER  1
+#define SQLITE_FLOAT    2
+#define SQLITE_BLOB     4
+#define SQLITE_NULL     5
+#ifdef SQLITE_TEXT
+# undef SQLITE_TEXT
+#else
+# define SQLITE_TEXT     3
+#endif
+#define SQLITE3_TEXT     3
+
+/*
+** CAPI3REF: Result Values From A Query
+** KEYWORDS: {column access functions}
+**
+** These routines form the "result set" interface.
+**
+** ^These routines return information about a single column of the current
+** result row of a query.  ^In every case the first argument is a pointer
+** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
+** that was returned from [sqlite3_prepare_v2()] or one of its variants)
+** and the second argument is the index of the column for which information
+** should be returned. ^The leftmost column of the result set has the index 0.
+** ^The number of columns in the result can be determined using
+** [sqlite3_column_count()].
+**
+** If the SQL statement does not currently point to a valid row, or if the
+** column index is out of range, the result is undefined.
+** These routines may only be called when the most recent call to
+** [sqlite3_step()] has returned [SQLITE_ROW] and neither
+** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
+** If any of these routines are called after [sqlite3_reset()] or
+** [sqlite3_finalize()] or after [sqlite3_step()] has returned
+** something other than [SQLITE_ROW], the results are undefined.
+** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
+** are called from a different thread while any of these routines
+** are pending, then the results are undefined.
+**
+** ^The sqlite3_column_type() routine returns the
+** [SQLITE_INTEGER | datatype code] for the initial data type
+** of the result column.  ^The returned value is one of [SQLITE_INTEGER],
+** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].  The value
+** returned by sqlite3_column_type() is only meaningful if no type
+** conversions have occurred as described below.  After a type conversion,
+** the value returned by sqlite3_column_type() is undefined.  Future
+** versions of SQLite may change the behavior of sqlite3_column_type()
+** following a type conversion.
+**
+** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
+** routine returns the number of bytes in that BLOB or string.
+** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts
+** the string to UTF-8 and then returns the number of bytes.
+** ^If the result is a numeric value then sqlite3_column_bytes() uses
+** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
+** the number of bytes in that string.
+** ^If the result is NULL, then sqlite3_column_bytes() returns zero.
+**
+** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16()
+** routine returns the number of bytes in that BLOB or string.
+** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts
+** the string to UTF-16 and then returns the number of bytes.
+** ^If the result is a numeric value then sqlite3_column_bytes16() uses
+** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns
+** the number of bytes in that string.
+** ^If the result is NULL, then sqlite3_column_bytes16() returns zero.
+**
+** ^The values returned by [sqlite3_column_bytes()] and 
+** [sqlite3_column_bytes16()] do not include the zero terminators at the end
+** of the string.  ^For clarity: the values returned by
+** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of
+** bytes in the string, not the number of characters.
+**
+** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
+** even empty strings, are always zero terminated.  ^The return
+** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.
+**
+** ^The object returned by [sqlite3_column_value()] is an
+** [unprotected sqlite3_value] object.  An unprotected sqlite3_value object
+** may only be used with [sqlite3_bind_value()] and [sqlite3_result_value()].
+** If the [unprotected sqlite3_value] object returned by
+** [sqlite3_column_value()] is used in any other way, including calls
+** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
+** or [sqlite3_value_bytes()], then the behavior is undefined.
+**
+** These routines attempt to convert the value where appropriate.  ^For
+** example, if the internal representation is FLOAT and a text result
+** is requested, [sqlite3_snprintf()] is used internally to perform the
+** conversion automatically.  ^(The following table details the conversions
+** that are applied:
+**
+** <blockquote>
+** <table border="1">
+** <tr><th> Internal<br>Type <th> Requested<br>Type <th>  Conversion
+**
+** <tr><td>  NULL    <td> INTEGER   <td> Result is 0
+** <tr><td>  NULL    <td>  FLOAT    <td> Result is 0.0
+** <tr><td>  NULL    <td>   TEXT    <td> Result is NULL pointer
+** <tr><td>  NULL    <td>   BLOB    <td> Result is NULL pointer
+** <tr><td> INTEGER  <td>  FLOAT    <td> Convert from integer to float
+** <tr><td> INTEGER  <td>   TEXT    <td> ASCII rendering of the integer
+** <tr><td> INTEGER  <td>   BLOB    <td> Same as INTEGER->TEXT
+** <tr><td>  FLOAT   <td> INTEGER   <td> Convert from float to integer
+** <tr><td>  FLOAT   <td>   TEXT    <td> ASCII rendering of the float
+** <tr><td>  FLOAT   <td>   BLOB    <td> Same as FLOAT->TEXT
+** <tr><td>  TEXT    <td> INTEGER   <td> Use atoi()
+** <tr><td>  TEXT    <td>  FLOAT    <td> Use atof()
+** <tr><td>  TEXT    <td>   BLOB    <td> No change
+** <tr><td>  BLOB    <td> INTEGER   <td> Convert to TEXT then use atoi()
+** <tr><td>  BLOB    <td>  FLOAT    <td> Convert to TEXT then use atof()
+** <tr><td>  BLOB    <td>   TEXT    <td> Add a zero terminator if needed
+** </table>
+** </blockquote>)^
+**
+** The table above makes reference to standard C library functions atoi()
+** and atof().  SQLite does not really use these functions.  It has its
+** own equivalent internal routines.  The atoi() and atof() names are
+** used in the table for brevity and because they are familiar to most
+** C programmers.
+**
+** Note that when type conversions occur, pointers returned by prior
+** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
+** sqlite3_column_text16() may be invalidated.
+** Type conversions and pointer invalidations might occur
+** in the following cases:
+**
+** <ul>
+** <li> The initial content is a BLOB and sqlite3_column_text() or
+**      sqlite3_column_text16() is called.  A zero-terminator might
+**      need to be added to the string.</li>
+** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
+**      sqlite3_column_text16() is called.  The content must be converted
+**      to UTF-16.</li>
+** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
+**      sqlite3_column_text() is called.  The content must be converted
+**      to UTF-8.</li>
+** </ul>
+**
+** ^Conversions between UTF-16be and UTF-16le are always done in place and do
+** not invalidate a prior pointer, though of course the content of the buffer
+** that the prior pointer references will have been modified.  Other kinds
+** of conversion are done in place when it is possible, but sometimes they
+** are not possible and in those cases prior pointers are invalidated.
+**
+** The safest and easiest to remember policy is to invoke these routines
+** in one of the following ways:
+**
+** <ul>
+**  <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
+**  <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
+**  <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
+** </ul>
+**
+** In other words, you should call sqlite3_column_text(),
+** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
+** into the desired format, then invoke sqlite3_column_bytes() or
+** sqlite3_column_bytes16() to find the size of the result.  Do not mix calls
+** to sqlite3_column_text() or sqlite3_column_blob() with calls to
+** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
+** with calls to sqlite3_column_bytes().
+**
+** ^The pointers returned are valid until a type conversion occurs as
+** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
+** [sqlite3_finalize()] is called.  ^The memory space used to hold strings
+** and BLOBs is freed automatically.  Do <b>not</b> pass the pointers returned
+** [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
+** [sqlite3_free()].
+**
+** ^(If a memory allocation error occurs during the evaluation of any
+** of these routines, a default value is returned.  The default value
+** is either the integer 0, the floating point number 0.0, or a NULL
+** pointer.  Subsequent calls to [sqlite3_errcode()] will return
+** [SQLITE_NOMEM].)^
+*/
+SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
+SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
+SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
+SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol);
+SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol);
+SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
+SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
+SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
+SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol);
+SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
+
+/*
+** CAPI3REF: Destroy A Prepared Statement Object
+**
+** ^The sqlite3_finalize() function is called to delete a [prepared statement].
+** ^If the statement was executed successfully or not executed at all, then
+** SQLITE_OK is returned. ^If execution of the statement failed then an
+** [error code] or [extended error code] is returned.
+**
+** ^This routine can be called at any point during the execution of the
+** [prepared statement].  ^If the virtual machine has not
+** completed execution when this routine is called, that is like
+** encountering an error or an [sqlite3_interrupt | interrupt].
+** ^Incomplete updates may be rolled back and transactions canceled,
+** depending on the circumstances, and the
+** [error code] returned will be [SQLITE_ABORT].
+*/
+SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt);
+
+/*
+** CAPI3REF: Reset A Prepared Statement Object
+**
+** The sqlite3_reset() function is called to reset a [prepared statement]
+** object back to its initial state, ready to be re-executed.
+** ^Any SQL statement variables that had values bound to them using
+** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
+** Use [sqlite3_clear_bindings()] to reset the bindings.
+**
+** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S
+** back to the beginning of its program.
+**
+** ^If the most recent call to [sqlite3_step(S)] for the
+** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
+** or if [sqlite3_step(S)] has never before been called on S,
+** then [sqlite3_reset(S)] returns [SQLITE_OK].
+**
+** ^If the most recent call to [sqlite3_step(S)] for the
+** [prepared statement] S indicated an error, then
+** [sqlite3_reset(S)] returns an appropriate [error code].
+**
+** ^The [sqlite3_reset(S)] interface does not change the values
+** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
+*/
+SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt);
+
+/*
+** CAPI3REF: Create Or Redefine SQL Functions
+** KEYWORDS: {function creation routines}
+** KEYWORDS: {application-defined SQL function}
+** KEYWORDS: {application-defined SQL functions}
+**
+** ^These functions (collectively known as "function creation routines")
+** are used to add SQL functions or aggregates or to redefine the behavior
+** of existing SQL functions or aggregates.  The only differences between
+** these routines are the text encoding expected for
+** the the second parameter (the name of the function being created)
+** and the presence or absence of a destructor callback for
+** the application data pointer.
+**
+** ^The first parameter is the [database connection] to which the SQL
+** function is to be added.  ^If an application uses more than one database
+** connection then application-defined SQL functions must be added
+** to each database connection separately.
+**
+** ^The second parameter is the name of the SQL function to be created or
+** redefined.  ^The length of the name is limited to 255 bytes in a UTF-8
+** representation, exclusive of the zero-terminator.  ^Note that the name
+** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes.  
+** ^Any attempt to create a function with a longer name
+** will result in [SQLITE_MISUSE] being returned.
+**
+** ^The third parameter (nArg)
+** is the number of arguments that the SQL function or
+** aggregate takes. ^If this parameter is -1, then the SQL function or
+** aggregate may take any number of arguments between 0 and the limit
+** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]).  If the third
+** parameter is less than -1 or greater than 127 then the behavior is
+** undefined.
+**
+** ^The fourth parameter, eTextRep, specifies what
+** [SQLITE_UTF8 | text encoding] this SQL function prefers for
+** its parameters.  Every SQL function implementation must be able to work
+** with UTF-8, UTF-16le, or UTF-16be.  But some implementations may be
+** more efficient with one encoding than another.  ^An application may
+** invoke sqlite3_create_function() or sqlite3_create_function16() multiple
+** times with the same function but with different values of eTextRep.
+** ^When multiple implementations of the same function are available, SQLite
+** will pick the one that involves the least amount of data conversion.
+** If there is only a single implementation which does not care what text
+** encoding is used, then the fourth argument should be [SQLITE_ANY].
+**
+** ^(The fifth parameter is an arbitrary pointer.  The implementation of the
+** function can gain access to this pointer using [sqlite3_user_data()].)^
+**
+** ^The seventh, eighth and ninth parameters, xFunc, xStep and xFinal, are
+** pointers to C-language functions that implement the SQL function or
+** aggregate. ^A scalar SQL function requires an implementation of the xFunc
+** callback only; NULL pointers must be passed as the xStep and xFinal
+** parameters. ^An aggregate SQL function requires an implementation of xStep
+** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing
+** SQL function or aggregate, pass NULL poiners for all three function
+** callbacks.
+**
+** ^If the tenth parameter to sqlite3_create_function_v2() is not NULL,
+** then it is invoked when the function is deleted, either by being
+** overloaded or when the database connection closes.
+** ^When the destructure callback of the tenth parameter is invoked, it
+** is passed a single argument which is a copy of the pointer which was
+** the fifth parameter to sqlite3_create_function_v2().
+**
+** ^It is permitted to register multiple implementations of the same
+** functions with the same name but with either differing numbers of
+** arguments or differing preferred text encodings.  ^SQLite will use
+** the implementation that most closely matches the way in which the
+** SQL function is used.  ^A function implementation with a non-negative
+** nArg parameter is a better match than a function implementation with
+** a negative nArg.  ^A function where the preferred text encoding
+** matches the database encoding is a better
+** match than a function where the encoding is different.  
+** ^A function where the encoding difference is between UTF16le and UTF16be
+** is a closer match than a function where the encoding difference is
+** between UTF8 and UTF16.
+**
+** ^Built-in functions may be overloaded by new application-defined functions.
+**
+** ^An application-defined function is permitted to call other
+** SQLite interfaces.  However, such calls must not
+** close the database connection nor finalize or reset the prepared
+** statement in which the function is running.
+*/
+SQLITE_API int sqlite3_create_function(
+  sqlite3 *db,
+  const char *zFunctionName,
+  int nArg,
+  int eTextRep,
+  void *pApp,
+  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
+  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
+  void (*xFinal)(sqlite3_context*)
+);
+SQLITE_API int sqlite3_create_function16(
+  sqlite3 *db,
+  const void *zFunctionName,
+  int nArg,
+  int eTextRep,
+  void *pApp,
+  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
+  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
+  void (*xFinal)(sqlite3_context*)
+);
+SQLITE_API int sqlite3_create_function_v2(
+  sqlite3 *db,
+  const char *zFunctionName,
+  int nArg,
+  int eTextRep,
+  void *pApp,
+  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
+  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
+  void (*xFinal)(sqlite3_context*),
+  void(*xDestroy)(void*)
+);
+
+/*
+** CAPI3REF: Text Encodings
+**
+** These constant define integer codes that represent the various
+** text encodings supported by SQLite.
+*/
+#define SQLITE_UTF8           1
+#define SQLITE_UTF16LE        2
+#define SQLITE_UTF16BE        3
+#define SQLITE_UTF16          4    /* Use native byte order */
+#define SQLITE_ANY            5    /* sqlite3_create_function only */
+#define SQLITE_UTF16_ALIGNED  8    /* sqlite3_create_collation only */
+
+/*
+** CAPI3REF: Deprecated Functions
+** DEPRECATED
+**
+** These functions are [deprecated].  In order to maintain
+** backwards compatibility with older code, these functions continue 
+** to be supported.  However, new applications should avoid
+** the use of these functions.  To help encourage people to avoid
+** using these functions, we are not going to tell you what they do.
+*/
+#ifndef SQLITE_OMIT_DEPRECATED
+SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
+SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
+SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
+SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void);
+SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
+SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64);
+#endif
+
+/*
+** CAPI3REF: Obtaining SQL Function Parameter Values
+**
+** The C-language implementation of SQL functions and aggregates uses
+** this set of interface routines to access the parameter values on
+** the function or aggregate.
+**
+** The xFunc (for scalar functions) or xStep (for aggregates) parameters
+** to [sqlite3_create_function()] and [sqlite3_create_function16()]
+** define callbacks that implement the SQL functions and aggregates.
+** The 4th parameter to these callbacks is an array of pointers to
+** [protected sqlite3_value] objects.  There is one [sqlite3_value] object for
+** each parameter to the SQL function.  These routines are used to
+** extract values from the [sqlite3_value] objects.
+**
+** These routines work only with [protected sqlite3_value] objects.
+** Any attempt to use these routines on an [unprotected sqlite3_value]
+** object results in undefined behavior.
+**
+** ^These routines work just like the corresponding [column access functions]
+** except that  these routines take a single [protected sqlite3_value] object
+** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
+**
+** ^The sqlite3_value_text16() interface extracts a UTF-16 string
+** in the native byte-order of the host machine.  ^The
+** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
+** extract UTF-16 strings as big-endian and little-endian respectively.
+**
+** ^(The sqlite3_value_numeric_type() interface attempts to apply
+** numeric affinity to the value.  This means that an attempt is
+** made to convert the value to an integer or floating point.  If
+** such a conversion is possible without loss of information (in other
+** words, if the value is a string that looks like a number)
+** then the conversion is performed.  Otherwise no conversion occurs.
+** The [SQLITE_INTEGER | datatype] after conversion is returned.)^
+**
+** Please pay particular attention to the fact that the pointer returned
+** from [sqlite3_value_blob()], [sqlite3_value_text()], or
+** [sqlite3_value_text16()] can be invalidated by a subsequent call to
+** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
+** or [sqlite3_value_text16()].
+**
+** These routines must be called from the same thread as
+** the SQL function that supplied the [sqlite3_value*] parameters.
+*/
+SQLITE_API const void *sqlite3_value_blob(sqlite3_value*);
+SQLITE_API int sqlite3_value_bytes(sqlite3_value*);
+SQLITE_API int sqlite3_value_bytes16(sqlite3_value*);
+SQLITE_API double sqlite3_value_double(sqlite3_value*);
+SQLITE_API int sqlite3_value_int(sqlite3_value*);
+SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
+SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*);
+SQLITE_API const void *sqlite3_value_text16(sqlite3_value*);
+SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*);
+SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*);
+SQLITE_API int sqlite3_value_type(sqlite3_value*);
+SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);
+
+/*
+** CAPI3REF: Obtain Aggregate Function Context
+**
+** Implementations of aggregate SQL functions use this
+** routine to allocate memory for storing their state.
+**
+** ^The first time the sqlite3_aggregate_context(C,N) routine is called 
+** for a particular aggregate function, SQLite
+** allocates N of memory, zeroes out that memory, and returns a pointer
+** to the new memory. ^On second and subsequent calls to
+** sqlite3_aggregate_context() for the same aggregate function instance,
+** the same buffer is returned.  Sqlite3_aggregate_context() is normally
+** called once for each invocation of the xStep callback and then one
+** last time when the xFinal callback is invoked.  ^(When no rows match
+** an aggregate query, the xStep() callback of the aggregate function
+** implementation is never called and xFinal() is called exactly once.
+** In those cases, sqlite3_aggregate_context() might be called for the
+** first time from within xFinal().)^
+**
+** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer if N is
+** less than or equal to zero or if a memory allocate error occurs.
+**
+** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
+** determined by the N parameter on first successful call.  Changing the
+** value of N in subsequent call to sqlite3_aggregate_context() within
+** the same aggregate function instance will not resize the memory
+** allocation.)^
+**
+** ^SQLite automatically frees the memory allocated by 
+** sqlite3_aggregate_context() when the aggregate query concludes.
+**
+** The first parameter must be a copy of the
+** [sqlite3_context | SQL function context] that is the first parameter
+** to the xStep or xFinal callback routine that implements the aggregate
+** function.
+**
+** This routine must be called from the same thread in which
+** the aggregate SQL function is running.
+*/
+SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
+
+/*
+** CAPI3REF: User Data For Functions
+**
+** ^The sqlite3_user_data() interface returns a copy of
+** the pointer that was the pUserData parameter (the 5th parameter)
+** of the [sqlite3_create_function()]
+** and [sqlite3_create_function16()] routines that originally
+** registered the application defined function.
+**
+** This routine must be called from the same thread in which
+** the application-defined function is running.
+*/
+SQLITE_API void *sqlite3_user_data(sqlite3_context*);
+
+/*
+** CAPI3REF: Database Connection For Functions
+**
+** ^The sqlite3_context_db_handle() interface returns a copy of
+** the pointer to the [database connection] (the 1st parameter)
+** of the [sqlite3_create_function()]
+** and [sqlite3_create_function16()] routines that originally
+** registered the application defined function.
+*/
+SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
+
+/*
+** CAPI3REF: Function Auxiliary Data
+**
+** The following two functions may be used by scalar SQL functions to
+** associate metadata with argument values. If the same value is passed to
+** multiple invocations of the same SQL function during query execution, under
+** some circumstances the associated metadata may be preserved. This may
+** be used, for example, to add a regular-expression matching scalar
+** function. The compiled version of the regular expression is stored as
+** metadata associated with the SQL value passed as the regular expression
+** pattern.  The compiled regular expression can be reused on multiple
+** invocations of the same function so that the original pattern string
+** does not need to be recompiled on each invocation.
+**
+** ^The sqlite3_get_auxdata() interface returns a pointer to the metadata
+** associated by the sqlite3_set_auxdata() function with the Nth argument
+** value to the application-defined function. ^If no metadata has been ever
+** been set for the Nth argument of the function, or if the corresponding
+** function parameter has changed since the meta-data was set,
+** then sqlite3_get_auxdata() returns a NULL pointer.
+**
+** ^The sqlite3_set_auxdata() interface saves the metadata
+** pointed to by its 3rd parameter as the metadata for the N-th
+** argument of the application-defined function.  Subsequent
+** calls to sqlite3_get_auxdata() might return this data, if it has
+** not been destroyed.
+** ^If it is not NULL, SQLite will invoke the destructor
+** function given by the 4th parameter to sqlite3_set_auxdata() on
+** the metadata when the corresponding function parameter changes
+** or when the SQL statement completes, whichever comes first.
+**
+** SQLite is free to call the destructor and drop metadata on any
+** parameter of any function at any time.  ^The only guarantee is that
+** the destructor will be called before the metadata is dropped.
+**
+** ^(In practice, metadata is preserved between function calls for
+** expressions that are constant at compile time. This includes literal
+** values and [parameters].)^
+**
+** These routines must be called from the same thread in which
+** the SQL function is running.
+*/
+SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N);
+SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
+
+
+/*
+** CAPI3REF: Constants Defining Special Destructor Behavior
+**
+** These are special values for the destructor that is passed in as the
+** final argument to routines like [sqlite3_result_blob()].  ^If the destructor
+** argument is SQLITE_STATIC, it means that the content pointer is constant
+** and will never change.  It does not need to be destroyed.  ^The
+** SQLITE_TRANSIENT value means that the content will likely change in
+** the near future and that SQLite should make its own private copy of
+** the content before returning.
+**
+** The typedef is necessary to work around problems in certain
+** C++ compilers.  See ticket #2191.
+*/
+typedef void (*sqlite3_destructor_type)(void*);
+#define SQLITE_STATIC      ((sqlite3_destructor_type)0)
+#define SQLITE_TRANSIENT   ((sqlite3_destructor_type)-1)
+
+/*
+** CAPI3REF: Setting The Result Of An SQL Function
+**
+** These routines are used by the xFunc or xFinal callbacks that
+** implement SQL functions and aggregates.  See
+** [sqlite3_create_function()] and [sqlite3_create_function16()]
+** for additional information.
+**
+** These functions work very much like the [parameter binding] family of
+** functions used to bind values to host parameters in prepared statements.
+** Refer to the [SQL parameter] documentation for additional information.
+**
+** ^The sqlite3_result_blob() interface sets the result from
+** an application-defined function to be the BLOB whose content is pointed
+** to by the second parameter and which is N bytes long where N is the
+** third parameter.
+**
+** ^The sqlite3_result_zeroblob() interfaces set the result of
+** the application-defined function to be a BLOB containing all zero
+** bytes and N bytes in size, where N is the value of the 2nd parameter.
+**
+** ^The sqlite3_result_double() interface sets the result from
+** an application-defined function to be a floating point value specified
+** by its 2nd argument.
+**
+** ^The sqlite3_result_error() and sqlite3_result_error16() functions
+** cause the implemented SQL function to throw an exception.
+** ^SQLite uses the string pointed to by the
+** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
+** as the text of an error message.  ^SQLite interprets the error
+** message string from sqlite3_result_error() as UTF-8. ^SQLite
+** interprets the string from sqlite3_result_error16() as UTF-16 in native
+** byte order.  ^If the third parameter to sqlite3_result_error()
+** or sqlite3_result_error16() is negative then SQLite takes as the error
+** message all text up through the first zero character.
+** ^If the third parameter to sqlite3_result_error() or
+** sqlite3_result_error16() is non-negative then SQLite takes that many
+** bytes (not characters) from the 2nd parameter as the error message.
+** ^The sqlite3_result_error() and sqlite3_result_error16()
+** routines make a private copy of the error message text before
+** they return.  Hence, the calling function can deallocate or
+** modify the text after they return without harm.
+** ^The sqlite3_result_error_code() function changes the error code
+** returned by SQLite as a result of an error in a function.  ^By default,
+** the error code is SQLITE_ERROR.  ^A subsequent call to sqlite3_result_error()
+** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
+**
+** ^The sqlite3_result_toobig() interface causes SQLite to throw an error
+** indicating that a string or BLOB is too long to represent.
+**
+** ^The sqlite3_result_nomem() interface causes SQLite to throw an error
+** indicating that a memory allocation failed.
+**
+** ^The sqlite3_result_int() interface sets the return value
+** of the application-defined function to be the 32-bit signed integer
+** value given in the 2nd argument.
+** ^The sqlite3_result_int64() interface sets the return value
+** of the application-defined function to be the 64-bit signed integer
+** value given in the 2nd argument.
+**
+** ^The sqlite3_result_null() interface sets the return value
+** of the application-defined function to be NULL.
+**
+** ^The sqlite3_result_text(), sqlite3_result_text16(),
+** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
+** set the return value of the application-defined function to be
+** a text string which is represented as UTF-8, UTF-16 native byte order,
+** UTF-16 little endian, or UTF-16 big endian, respectively.
+** ^SQLite takes the text result from the application from
+** the 2nd parameter of the sqlite3_result_text* interfaces.
+** ^If the 3rd parameter to the sqlite3_result_text* interfaces
+** is negative, then SQLite takes result text from the 2nd parameter
+** through the first zero character.
+** ^If the 3rd parameter to the sqlite3_result_text* interfaces
+** is non-negative, then as many bytes (not characters) of the text
+** pointed to by the 2nd parameter are taken as the application-defined
+** function result.
+** ^If the 4th parameter to the sqlite3_result_text* interfaces
+** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
+** function as the destructor on the text or BLOB result when it has
+** finished using that result.
+** ^If the 4th parameter to the sqlite3_result_text* interfaces or to
+** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
+** assumes that the text or BLOB result is in constant space and does not
+** copy the content of the parameter nor call a destructor on the content
+** when it has finished using that result.
+** ^If the 4th parameter to the sqlite3_result_text* interfaces
+** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
+** then SQLite makes a copy of the result into space obtained from
+** from [sqlite3_malloc()] before it returns.
+**
+** ^The sqlite3_result_value() interface sets the result of
+** the application-defined function to be a copy the
+** [unprotected sqlite3_value] object specified by the 2nd parameter.  ^The
+** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
+** so that the [sqlite3_value] specified in the parameter may change or
+** be deallocated after sqlite3_result_value() returns without harm.
+** ^A [protected sqlite3_value] object may always be used where an
+** [unprotected sqlite3_value] object is required, so either
+** kind of [sqlite3_value] object can be used with this interface.
+**
+** If these routines are called from within the different thread
+** than the one containing the application-defined function that received
+** the [sqlite3_context] pointer, the results are undefined.
+*/
+SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
+SQLITE_API void sqlite3_result_double(sqlite3_context*, double);
+SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int);
+SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int);
+SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*);
+SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*);
+SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int);
+SQLITE_API void sqlite3_result_int(sqlite3_context*, int);
+SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
+SQLITE_API void sqlite3_result_null(sqlite3_context*);
+SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
+SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
+SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
+SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
+SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
+SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n);
+
+/*
+** CAPI3REF: Define New Collating Sequences
+**
+** ^These functions add, remove, or modify a [collation] associated
+** with the [database connection] specified as the first argument.
+**
+** ^The name of the collation is a UTF-8 string
+** for sqlite3_create_collation() and sqlite3_create_collation_v2()
+** and a UTF-16 string in native byte order for sqlite3_create_collation16().
+** ^Collation names that compare equal according to [sqlite3_strnicmp()] are
+** considered to be the same name.
+**
+** ^(The third argument (eTextRep) must be one of the constants:
+** <ul>
+** <li> [SQLITE_UTF8],
+** <li> [SQLITE_UTF16LE],
+** <li> [SQLITE_UTF16BE],
+** <li> [SQLITE_UTF16], or
+** <li> [SQLITE_UTF16_ALIGNED].
+** </ul>)^
+** ^The eTextRep argument determines the encoding of strings passed
+** to the collating function callback, xCallback.
+** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep
+** force strings to be UTF16 with native byte order.
+** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin
+** on an even byte address.
+**
+** ^The fourth argument, pArg, is a application data pointer that is passed
+** through as the first argument to the collating function callback.
+**
+** ^The fifth argument, xCallback, is a pointer to the collating function.
+** ^Multiple collating functions can be registered using the same name but
+** with different eTextRep parameters and SQLite will use whichever
+** function requires the least amount of data transformation.
+** ^If the xCallback argument is NULL then the collating function is
+** deleted.  ^When all collating functions having the same name are deleted,
+** that collation is no longer usable.
+**
+** ^The collating function callback is invoked with a copy of the pArg 
+** application data pointer and with two strings in the encoding specified
+** by the eTextRep argument.  The collating function must return an
+** integer that is negative, zero, or positive
+** if the first string is less than, equal to, or greater than the second,
+** respectively.  A collating function must alway return the same answer
+** given the same inputs.  If two or more collating functions are registered
+** to the same collation name (using different eTextRep values) then all
+** must give an equivalent answer when invoked with equivalent strings.
+** The collating function must obey the following properties for all
+** strings A, B, and C:
+**
+** <ol>
+** <li> If A==B then B==A.
+** <li> If A==B and B==C then A==C.
+** <li> If A&lt;B THEN B&gt;A.
+** <li> If A&lt;B and B&lt;C then A&lt;C.
+** </ol>
+**
+** If a collating function fails any of the above constraints and that
+** collating function is  registered and used, then the behavior of SQLite
+** is undefined.
+**
+** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()
+** with the addition that the xDestroy callback is invoked on pArg when
+** the collating function is deleted.
+** ^Collating functions are deleted when they are overridden by later
+** calls to the collation creation functions or when the
+** [database connection] is closed using [sqlite3_close()].
+**
+** See also:  [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
+*/
+SQLITE_API int sqlite3_create_collation(
+  sqlite3*, 
+  const char *zName, 
+  int eTextRep, 
+  void *pArg,
+  int(*xCompare)(void*,int,const void*,int,const void*)
+);
+SQLITE_API int sqlite3_create_collation_v2(
+  sqlite3*, 
+  const char *zName, 
+  int eTextRep, 
+  void *pArg,
+  int(*xCompare)(void*,int,const void*,int,const void*),
+  void(*xDestroy)(void*)
+);
+SQLITE_API int sqlite3_create_collation16(
+  sqlite3*, 
+  const void *zName,
+  int eTextRep, 
+  void *pArg,
+  int(*xCompare)(void*,int,const void*,int,const void*)
+);
+
+/*
+** CAPI3REF: Collation Needed Callbacks
+**
+** ^To avoid having to register all collation sequences before a database
+** can be used, a single callback function may be registered with the
+** [database connection] to be invoked whenever an undefined collation
+** sequence is required.
+**
+** ^If the function is registered using the sqlite3_collation_needed() API,
+** then it is passed the names of undefined collation sequences as strings
+** encoded in UTF-8. ^If sqlite3_collation_needed16() is used,
+** the names are passed as UTF-16 in machine native byte order.
+** ^A call to either function replaces the existing collation-needed callback.
+**
+** ^(When the callback is invoked, the first argument passed is a copy
+** of the second argument to sqlite3_collation_needed() or
+** sqlite3_collation_needed16().  The second argument is the database
+** connection.  The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
+** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
+** sequence function required.  The fourth parameter is the name of the
+** required collation sequence.)^
+**
+** The callback function should register the desired collation using
+** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
+** [sqlite3_create_collation_v2()].
+*/
+SQLITE_API int sqlite3_collation_needed(
+  sqlite3*, 
+  void*, 
+  void(*)(void*,sqlite3*,int eTextRep,const char*)
+);
+SQLITE_API int sqlite3_collation_needed16(
+  sqlite3*, 
+  void*,
+  void(*)(void*,sqlite3*,int eTextRep,const void*)
+);
+
+#ifdef SQLITE_HAS_CODEC
+/*
+** Specify the key for an encrypted database.  This routine should be
+** called right after sqlite3_open().
+**
+** The code to implement this API is not available in the public release
+** of SQLite.
+*/
+SQLITE_API int sqlite3_key(
+  sqlite3 *db,                   /* Database to be rekeyed */
+  const void *pKey, int nKey     /* The key */
+);
+
+/*
+** Change the key on an open database.  If the current database is not
+** encrypted, this routine will encrypt it.  If pNew==0 or nNew==0, the
+** database is decrypted.
+**
+** The code to implement this API is not available in the public release
+** of SQLite.
+*/
+SQLITE_API int sqlite3_rekey(
+  sqlite3 *db,                   /* Database to be rekeyed */
+  const void *pKey, int nKey     /* The new key */
+);
+
+/*
+** Specify the activation key for a SEE database.  Unless 
+** activated, none of the SEE routines will work.
+*/
+SQLITE_API void sqlite3_activate_see(
+  const char *zPassPhrase        /* Activation phrase */
+);
+#endif
+
+#ifdef SQLITE_ENABLE_CEROD
+/*
+** Specify the activation key for a CEROD database.  Unless 
+** activated, none of the CEROD routines will work.
+*/
+SQLITE_API void sqlite3_activate_cerod(
+  const char *zPassPhrase        /* Activation phrase */
+);
+#endif
+
+/*
+** CAPI3REF: Suspend Execution For A Short Time
+**
+** The sqlite3_sleep() function causes the current thread to suspend execution
+** for at least a number of milliseconds specified in its parameter.
+**
+** If the operating system does not support sleep requests with
+** millisecond time resolution, then the time will be rounded up to
+** the nearest second. The number of milliseconds of sleep actually
+** requested from the operating system is returned.
+**
+** ^SQLite implements this interface by calling the xSleep()
+** method of the default [sqlite3_vfs] object.  If the xSleep() method
+** of the default VFS is not implemented correctly, or not implemented at
+** all, then the behavior of sqlite3_sleep() may deviate from the description
+** in the previous paragraphs.
+*/
+SQLITE_API int sqlite3_sleep(int);
+
+/*
+** CAPI3REF: Name Of The Folder Holding Temporary Files
+**
+** ^(If this global variable is made to point to a string which is
+** the name of a folder (a.k.a. directory), then all temporary files
+** created by SQLite when using a built-in [sqlite3_vfs | VFS]
+** will be placed in that directory.)^  ^If this variable
+** is a NULL pointer, then SQLite performs a search for an appropriate
+** temporary file directory.
+**
+** It is not safe to read or modify this variable in more than one
+** thread at a time.  It is not safe to read or modify this variable
+** if a [database connection] is being used at the same time in a separate
+** thread.
+** It is intended that this variable be set once
+** as part of process initialization and before any SQLite interface
+** routines have been called and that this variable remain unchanged
+** thereafter.
+**
+** ^The [temp_store_directory pragma] may modify this variable and cause
+** it to point to memory obtained from [sqlite3_malloc].  ^Furthermore,
+** the [temp_store_directory pragma] always assumes that any string
+** that this variable points to is held in memory obtained from 
+** [sqlite3_malloc] and the pragma may attempt to free that memory
+** using [sqlite3_free].
+** Hence, if this variable is modified directly, either it should be
+** made NULL or made to point to memory obtained from [sqlite3_malloc]
+** or else the use of the [temp_store_directory pragma] should be avoided.
+*/
+SQLITE_API SQLITE_EXTERN char *sqlite3_temp_directory;
+
+/*
+** CAPI3REF: Test For Auto-Commit Mode
+** KEYWORDS: {autocommit mode}
+**
+** ^The sqlite3_get_autocommit() interface returns non-zero or
+** zero if the given database connection is or is not in autocommit mode,
+** respectively.  ^Autocommit mode is on by default.
+** ^Autocommit mode is disabled by a [BEGIN] statement.
+** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
+**
+** If certain kinds of errors occur on a statement within a multi-statement
+** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
+** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
+** transaction might be rolled back automatically.  The only way to
+** find out whether SQLite automatically rolled back the transaction after
+** an error is to use this function.
+**
+** If another thread changes the autocommit status of the database
+** connection while this routine is running, then the return value
+** is undefined.
+*/
+SQLITE_API int sqlite3_get_autocommit(sqlite3*);
+
+/*
+** CAPI3REF: Find The Database Handle Of A Prepared Statement
+**
+** ^The sqlite3_db_handle interface returns the [database connection] handle
+** to which a [prepared statement] belongs.  ^The [database connection]
+** returned by sqlite3_db_handle is the same [database connection]
+** that was the first argument
+** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
+** create the statement in the first place.
+*/
+SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
+
+/*
+** CAPI3REF: Find the next prepared statement
+**
+** ^This interface returns a pointer to the next [prepared statement] after
+** pStmt associated with the [database connection] pDb.  ^If pStmt is NULL
+** then this interface returns a pointer to the first prepared statement
+** associated with the database connection pDb.  ^If no prepared statement
+** satisfies the conditions of this routine, it returns NULL.
+**
+** The [database connection] pointer D in a call to
+** [sqlite3_next_stmt(D,S)] must refer to an open database
+** connection and in particular must not be a NULL pointer.
+*/
+SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
+
+/*
+** CAPI3REF: Commit And Rollback Notification Callbacks
+**
+** ^The sqlite3_commit_hook() interface registers a callback
+** function to be invoked whenever a transaction is [COMMIT | committed].
+** ^Any callback set by a previous call to sqlite3_commit_hook()
+** for the same database connection is overridden.
+** ^The sqlite3_rollback_hook() interface registers a callback
+** function to be invoked whenever a transaction is [ROLLBACK | rolled back].
+** ^Any callback set by a previous call to sqlite3_rollback_hook()
+** for the same database connection is overridden.
+** ^The pArg argument is passed through to the callback.
+** ^If the callback on a commit hook function returns non-zero,
+** then the commit is converted into a rollback.
+**
+** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions
+** return the P argument from the previous call of the same function
+** on the same [database connection] D, or NULL for
+** the first call for each function on D.
+**
+** The callback implementation must not do anything that will modify
+** the database connection that invoked the callback.  Any actions
+** to modify the database connection must be deferred until after the
+** completion of the [sqlite3_step()] call that triggered the commit
+** or rollback hook in the first place.
+** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
+** database connections for the meaning of "modify" in this paragraph.
+**
+** ^Registering a NULL function disables the callback.
+**
+** ^When the commit hook callback routine returns zero, the [COMMIT]
+** operation is allowed to continue normally.  ^If the commit hook
+** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK].
+** ^The rollback hook is invoked on a rollback that results from a commit
+** hook returning non-zero, just as it would be with any other rollback.
+**
+** ^For the purposes of this API, a transaction is said to have been
+** rolled back if an explicit "ROLLBACK" statement is executed, or
+** an error or constraint causes an implicit rollback to occur.
+** ^The rollback callback is not invoked if a transaction is
+** automatically rolled back because the database connection is closed.
+**
+** See also the [sqlite3_update_hook()] interface.
+*/
+SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
+SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
+
+/*
+** CAPI3REF: Data Change Notification Callbacks
+**
+** ^The sqlite3_update_hook() interface registers a callback function
+** with the [database connection] identified by the first argument
+** to be invoked whenever a row is updated, inserted or deleted.
+** ^Any callback set by a previous call to this function
+** for the same database connection is overridden.
+**
+** ^The second argument is a pointer to the function to invoke when a
+** row is updated, inserted or deleted.
+** ^The first argument to the callback is a copy of the third argument
+** to sqlite3_update_hook().
+** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
+** or [SQLITE_UPDATE], depending on the operation that caused the callback
+** to be invoked.
+** ^The third and fourth arguments to the callback contain pointers to the
+** database and table name containing the affected row.
+** ^The final callback parameter is the [rowid] of the row.
+** ^In the case of an update, this is the [rowid] after the update takes place.
+**
+** ^(The update hook is not invoked when internal system tables are
+** modified (i.e. sqlite_master and sqlite_sequence).)^
+**
+** ^In the current implementation, the update hook
+** is not invoked when duplication rows are deleted because of an
+** [ON CONFLICT | ON CONFLICT REPLACE] clause.  ^Nor is the update hook
+** invoked when rows are deleted using the [truncate optimization].
+** The exceptions defined in this paragraph might change in a future
+** release of SQLite.
+**
+** The update hook implementation must not do anything that will modify
+** the database connection that invoked the update hook.  Any actions
+** to modify the database connection must be deferred until after the
+** completion of the [sqlite3_step()] call that triggered the update hook.
+** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
+** database connections for the meaning of "modify" in this paragraph.
+**
+** ^The sqlite3_update_hook(D,C,P) function
+** returns the P argument from the previous call
+** on the same [database connection] D, or NULL for
+** the first call on D.
+**
+** See also the [sqlite3_commit_hook()] and [sqlite3_rollback_hook()]
+** interfaces.
+*/
+SQLITE_API void *sqlite3_update_hook(
+  sqlite3*, 
+  void(*)(void *,int ,char const *,char const *,sqlite3_int64),
+  void*
+);
+
+/*
+** CAPI3REF: Enable Or Disable Shared Pager Cache
+** KEYWORDS: {shared cache}
+**
+** ^(This routine enables or disables the sharing of the database cache
+** and schema data structures between [database connection | connections]
+** to the same database. Sharing is enabled if the argument is true
+** and disabled if the argument is false.)^
+**
+** ^Cache sharing is enabled and disabled for an entire process.
+** This is a change as of SQLite version 3.5.0. In prior versions of SQLite,
+** sharing was enabled or disabled for each thread separately.
+**
+** ^(The cache sharing mode set by this interface effects all subsequent
+** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
+** Existing database connections continue use the sharing mode
+** that was in effect at the time they were opened.)^
+**
+** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled
+** successfully.  An [error code] is returned otherwise.)^
+**
+** ^Shared cache is disabled by default. But this might change in
+** future releases of SQLite.  Applications that care about shared
+** cache setting should set it explicitly.
+**
+** See Also:  [SQLite Shared-Cache Mode]
+*/
+SQLITE_API int sqlite3_enable_shared_cache(int);
+
+/*
+** CAPI3REF: Attempt To Free Heap Memory
+**
+** ^The sqlite3_release_memory() interface attempts to free N bytes
+** of heap memory by deallocating non-essential memory allocations
+** held by the database library.   Memory used to cache database
+** pages to improve performance is an example of non-essential memory.
+** ^sqlite3_release_memory() returns the number of bytes actually freed,
+** which might be more or less than the amount requested.
+** ^The sqlite3_release_memory() routine is a no-op returning zero
+** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT].
+*/
+SQLITE_API int sqlite3_release_memory(int);
+
+/*
+** CAPI3REF: Impose A Limit On Heap Size
+**
+** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the
+** soft limit on the amount of heap memory that may be allocated by SQLite.
+** ^SQLite strives to keep heap memory utilization below the soft heap
+** limit by reducing the number of pages held in the page cache
+** as heap memory usages approaches the limit.
+** ^The soft heap limit is "soft" because even though SQLite strives to stay
+** below the limit, it will exceed the limit rather than generate
+** an [SQLITE_NOMEM] error.  In other words, the soft heap limit 
+** is advisory only.
+**
+** ^The return value from sqlite3_soft_heap_limit64() is the size of
+** the soft heap limit prior to the call.  ^If the argument N is negative
+** then no change is made to the soft heap limit.  Hence, the current
+** size of the soft heap limit can be determined by invoking
+** sqlite3_soft_heap_limit64() with a negative argument.
+**
+** ^If the argument N is zero then the soft heap limit is disabled.
+**
+** ^(The soft heap limit is not enforced in the current implementation
+** if one or more of following conditions are true:
+**
+** <ul>
+** <li> The soft heap limit is set to zero.
+** <li> Memory accounting is disabled using a combination of the
+**      [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and
+**      the [SQLITE_DEFAULT_MEMSTATUS] compile-time option.
+** <li> An alternative page cache implementation is specifed using
+**      [sqlite3_config]([SQLITE_CONFIG_PCACHE],...).
+** <li> The page cache allocates from its own memory pool supplied
+**      by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than
+**      from the heap.
+** </ul>)^
+**
+** Beginning with SQLite version 3.7.3, the soft heap limit is enforced
+** regardless of whether or not the [SQLITE_ENABLE_MEMORY_MANAGEMENT]
+** compile-time option is invoked.  With [SQLITE_ENABLE_MEMORY_MANAGEMENT],
+** the soft heap limit is enforced on every memory allocation.  Without
+** [SQLITE_ENABLE_MEMORY_MANAGEMENT], the soft heap limit is only enforced
+** when memory is allocated by the page cache.  Testing suggests that because
+** the page cache is the predominate memory user in SQLite, most
+** applications will achieve adequate soft heap limit enforcement without
+** the use of [SQLITE_ENABLE_MEMORY_MANAGEMENT].
+**
+** The circumstances under which SQLite will enforce the soft heap limit may
+** changes in future releases of SQLite.
+*/
+SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N);
+
+/*
+** CAPI3REF: Deprecated Soft Heap Limit Interface
+** DEPRECATED
+**
+** This is a deprecated version of the [sqlite3_soft_heap_limit64()]
+** interface.  This routine is provided for historical compatibility
+** only.  All new applications should use the
+** [sqlite3_soft_heap_limit64()] interface rather than this one.
+*/
+SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N);
+
+
+/*
+** CAPI3REF: Extract Metadata About A Column Of A Table
+**
+** ^This routine returns metadata about a specific column of a specific
+** database table accessible using the [database connection] handle
+** passed as the first function argument.
+**
+** ^The column is identified by the second, third and fourth parameters to
+** this function. ^The second parameter is either the name of the database
+** (i.e. "main", "temp", or an attached database) containing the specified
+** table or NULL. ^If it is NULL, then all attached databases are searched
+** for the table using the same algorithm used by the database engine to
+** resolve unqualified table references.
+**
+** ^The third and fourth parameters to this function are the table and column
+** name of the desired column, respectively. Neither of these parameters
+** may be NULL.
+**
+** ^Metadata is returned by writing to the memory locations passed as the 5th
+** and subsequent parameters to this function. ^Any of these arguments may be
+** NULL, in which case the corresponding element of metadata is omitted.
+**
+** ^(<blockquote>
+** <table border="1">
+** <tr><th> Parameter <th> Output<br>Type <th>  Description
+**
+** <tr><td> 5th <td> const char* <td> Data type
+** <tr><td> 6th <td> const char* <td> Name of default collation sequence
+** <tr><td> 7th <td> int         <td> True if column has a NOT NULL constraint
+** <tr><td> 8th <td> int         <td> True if column is part of the PRIMARY KEY
+** <tr><td> 9th <td> int         <td> True if column is [AUTOINCREMENT]
+** </table>
+** </blockquote>)^
+**
+** ^The memory pointed to by the character pointers returned for the
+** declaration type and collation sequence is valid only until the next
+** call to any SQLite API function.
+**
+** ^If the specified table is actually a view, an [error code] is returned.
+**
+** ^If the specified column is "rowid", "oid" or "_rowid_" and an
+** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
+** parameters are set for the explicitly declared column. ^(If there is no
+** explicitly declared [INTEGER PRIMARY KEY] column, then the output
+** parameters are set as follows:
+**
+** <pre>
+**     data type: "INTEGER"
+**     collation sequence: "BINARY"
+**     not null: 0
+**     primary key: 1
+**     auto increment: 0
+** </pre>)^
+**
+** ^(This function may load one or more schemas from database files. If an
+** error occurs during this process, or if the requested table or column
+** cannot be found, an [error code] is returned and an error message left
+** in the [database connection] (to be retrieved using sqlite3_errmsg()).)^
+**
+** ^This API is only available if the library was compiled with the
+** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
+*/
+SQLITE_API int sqlite3_table_column_metadata(
+  sqlite3 *db,                /* Connection handle */
+  const char *zDbName,        /* Database name or NULL */
+  const char *zTableName,     /* Table name */
+  const char *zColumnName,    /* Column name */
+  char const **pzDataType,    /* OUTPUT: Declared data type */
+  char const **pzCollSeq,     /* OUTPUT: Collation sequence name */
+  int *pNotNull,              /* OUTPUT: True if NOT NULL constraint exists */
+  int *pPrimaryKey,           /* OUTPUT: True if column part of PK */
+  int *pAutoinc               /* OUTPUT: True if column is auto-increment */
+);
+
+/*
+** CAPI3REF: Load An Extension
+**
+** ^This interface loads an SQLite extension library from the named file.
+**
+** ^The sqlite3_load_extension() interface attempts to load an
+** SQLite extension library contained in the file zFile.
+**
+** ^The entry point is zProc.
+** ^zProc may be 0, in which case the name of the entry point
+** defaults to "sqlite3_extension_init".
+** ^The sqlite3_load_extension() interface returns
+** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
+** ^If an error occurs and pzErrMsg is not 0, then the
+** [sqlite3_load_extension()] interface shall attempt to
+** fill *pzErrMsg with error message text stored in memory
+** obtained from [sqlite3_malloc()]. The calling function
+** should free this memory by calling [sqlite3_free()].
+**
+** ^Extension loading must be enabled using
+** [sqlite3_enable_load_extension()] prior to calling this API,
+** otherwise an error will be returned.
+**
+** See also the [load_extension() SQL function].
+*/
+SQLITE_API int sqlite3_load_extension(
+  sqlite3 *db,          /* Load the extension into this database connection */
+  const char *zFile,    /* Name of the shared library containing extension */
+  const char *zProc,    /* Entry point.  Derived from zFile if 0 */
+  char **pzErrMsg       /* Put error message here if not 0 */
+);
+
+/*
+** CAPI3REF: Enable Or Disable Extension Loading
+**
+** ^So as not to open security holes in older applications that are
+** unprepared to deal with extension loading, and as a means of disabling
+** extension loading while evaluating user-entered SQL, the following API
+** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
+**
+** ^Extension loading is off by default. See ticket #1863.
+** ^Call the sqlite3_enable_load_extension() routine with onoff==1
+** to turn extension loading on and call it with onoff==0 to turn
+** it back off again.
+*/
+SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
+
+/*
+** CAPI3REF: Automatically Load Statically Linked Extensions
+**
+** ^This interface causes the xEntryPoint() function to be invoked for
+** each new [database connection] that is created.  The idea here is that
+** xEntryPoint() is the entry point for a statically linked SQLite extension
+** that is to be automatically loaded into all new database connections.
+**
+** ^(Even though the function prototype shows that xEntryPoint() takes
+** no arguments and returns void, SQLite invokes xEntryPoint() with three
+** arguments and expects and integer result as if the signature of the
+** entry point where as follows:
+**
+** <blockquote><pre>
+** &nbsp;  int xEntryPoint(
+** &nbsp;    sqlite3 *db,
+** &nbsp;    const char **pzErrMsg,
+** &nbsp;    const struct sqlite3_api_routines *pThunk
+** &nbsp;  );
+** </pre></blockquote>)^
+**
+** If the xEntryPoint routine encounters an error, it should make *pzErrMsg
+** point to an appropriate error message (obtained from [sqlite3_mprintf()])
+** and return an appropriate [error code].  ^SQLite ensures that *pzErrMsg
+** is NULL before calling the xEntryPoint().  ^SQLite will invoke
+** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns.  ^If any
+** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()],
+** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail.
+**
+** ^Calling sqlite3_auto_extension(X) with an entry point X that is already
+** on the list of automatic extensions is a harmless no-op. ^No entry point
+** will be called more than once for each database connection that is opened.
+**
+** See also: [sqlite3_reset_auto_extension()].
+*/
+SQLITE_API int sqlite3_auto_extension(void (*xEntryPoint)(void));
+
+/*
+** CAPI3REF: Reset Automatic Extension Loading
+**
+** ^This interface disables all automatic extensions previously
+** registered using [sqlite3_auto_extension()].
+*/
+SQLITE_API void sqlite3_reset_auto_extension(void);
+
+/*
+** The interface to the virtual-table mechanism is currently considered
+** to be experimental.  The interface might change in incompatible ways.
+** If this is a problem for you, do not use the interface at this time.
+**
+** When the virtual-table mechanism stabilizes, we will declare the
+** interface fixed, support it indefinitely, and remove this comment.
+*/
+
+/*
+** Structures used by the virtual table interface
+*/
+typedef struct sqlite3_vtab sqlite3_vtab;
+typedef struct sqlite3_index_info sqlite3_index_info;
+typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
+typedef struct sqlite3_module sqlite3_module;
+
+/*
+** CAPI3REF: Virtual Table Object
+** KEYWORDS: sqlite3_module {virtual table module}
+**
+** This structure, sometimes called a a "virtual table module", 
+** defines the implementation of a [virtual tables].  
+** This structure consists mostly of methods for the module.
+**
+** ^A virtual table module is created by filling in a persistent
+** instance of this structure and passing a pointer to that instance
+** to [sqlite3_create_module()] or [sqlite3_create_module_v2()].
+** ^The registration remains valid until it is replaced by a different
+** module or until the [database connection] closes.  The content
+** of this structure must not change while it is registered with
+** any database connection.
+*/
+struct sqlite3_module {
+  int iVersion;
+  int (*xCreate)(sqlite3*, void *pAux,
+               int argc, const char *const*argv,
+               sqlite3_vtab **ppVTab, char**);
+  int (*xConnect)(sqlite3*, void *pAux,
+               int argc, const char *const*argv,
+               sqlite3_vtab **ppVTab, char**);
+  int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
+  int (*xDisconnect)(sqlite3_vtab *pVTab);
+  int (*xDestroy)(sqlite3_vtab *pVTab);
+  int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
+  int (*xClose)(sqlite3_vtab_cursor*);
+  int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
+                int argc, sqlite3_value **argv);
+  int (*xNext)(sqlite3_vtab_cursor*);
+  int (*xEof)(sqlite3_vtab_cursor*);
+  int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
+  int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
+  int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
+  int (*xBegin)(sqlite3_vtab *pVTab);
+  int (*xSync)(sqlite3_vtab *pVTab);
+  int (*xCommit)(sqlite3_vtab *pVTab);
+  int (*xRollback)(sqlite3_vtab *pVTab);
+  int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
+                       void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
+                       void **ppArg);
+  int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
+};
+
+/*
+** CAPI3REF: Virtual Table Indexing Information
+** KEYWORDS: sqlite3_index_info
+**
+** The sqlite3_index_info structure and its substructures is used as part
+** of the [virtual table] interface to
+** pass information into and receive the reply from the [xBestIndex]
+** method of a [virtual table module].  The fields under **Inputs** are the
+** inputs to xBestIndex and are read-only.  xBestIndex inserts its
+** results into the **Outputs** fields.
+**
+** ^(The aConstraint[] array records WHERE clause constraints of the form:
+**
+** <blockquote>column OP expr</blockquote>
+**
+** where OP is =, &lt;, &lt;=, &gt;, or &gt;=.)^  ^(The particular operator is
+** stored in aConstraint[].op using one of the
+** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^
+** ^(The index of the column is stored in
+** aConstraint[].iColumn.)^  ^(aConstraint[].usable is TRUE if the
+** expr on the right-hand side can be evaluated (and thus the constraint
+** is usable) and false if it cannot.)^
+**
+** ^The optimizer automatically inverts terms of the form "expr OP column"
+** and makes other simplifications to the WHERE clause in an attempt to
+** get as many WHERE clause terms into the form shown above as possible.
+** ^The aConstraint[] array only reports WHERE clause terms that are
+** relevant to the particular virtual table being queried.
+**
+** ^Information about the ORDER BY clause is stored in aOrderBy[].
+** ^Each term of aOrderBy records a column of the ORDER BY clause.
+**
+** The [xBestIndex] method must fill aConstraintUsage[] with information
+** about what parameters to pass to xFilter.  ^If argvIndex>0 then
+** the right-hand side of the corresponding aConstraint[] is evaluated
+** and becomes the argvIndex-th entry in argv.  ^(If aConstraintUsage[].omit
+** is true, then the constraint is assumed to be fully handled by the
+** virtual table and is not checked again by SQLite.)^
+**
+** ^The idxNum and idxPtr values are recorded and passed into the
+** [xFilter] method.
+** ^[sqlite3_free()] is used to free idxPtr if and only if
+** needToFreeIdxPtr is true.
+**
+** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
+** the correct order to satisfy the ORDER BY clause so that no separate
+** sorting step is required.
+**
+** ^The estimatedCost value is an estimate of the cost of doing the
+** particular lookup.  A full scan of a table with N entries should have
+** a cost of N.  A binary search of a table of N entries should have a
+** cost of approximately log(N).
+*/
+struct sqlite3_index_info {
+  /* Inputs */
+  int nConstraint;           /* Number of entries in aConstraint */
+  struct sqlite3_index_constraint {
+     int iColumn;              /* Column on left-hand side of constraint */
+     unsigned char op;         /* Constraint operator */
+     unsigned char usable;     /* True if this constraint is usable */
+     int iTermOffset;          /* Used internally - xBestIndex should ignore */
+  } *aConstraint;            /* Table of WHERE clause constraints */
+  int nOrderBy;              /* Number of terms in the ORDER BY clause */
+  struct sqlite3_index_orderby {
+     int iColumn;              /* Column number */
+     unsigned char desc;       /* True for DESC.  False for ASC. */
+  } *aOrderBy;               /* The ORDER BY clause */
+  /* Outputs */
+  struct sqlite3_index_constraint_usage {
+    int argvIndex;           /* if >0, constraint is part of argv to xFilter */
+    unsigned char omit;      /* Do not code a test for this constraint */
+  } *aConstraintUsage;
+  int idxNum;                /* Number used to identify the index */
+  char *idxStr;              /* String, possibly obtained from sqlite3_malloc */
+  int needToFreeIdxStr;      /* Free idxStr using sqlite3_free() if true */
+  int orderByConsumed;       /* True if output is already ordered */
+  double estimatedCost;      /* Estimated cost of using this index */
+};
+
+/*
+** CAPI3REF: Virtual Table Constraint Operator Codes
+**
+** These macros defined the allowed values for the
+** [sqlite3_index_info].aConstraint[].op field.  Each value represents
+** an operator that is part of a constraint term in the wHERE clause of
+** a query that uses a [virtual table].
+*/
+#define SQLITE_INDEX_CONSTRAINT_EQ    2
+#define SQLITE_INDEX_CONSTRAINT_GT    4
+#define SQLITE_INDEX_CONSTRAINT_LE    8
+#define SQLITE_INDEX_CONSTRAINT_LT    16
+#define SQLITE_INDEX_CONSTRAINT_GE    32
+#define SQLITE_INDEX_CONSTRAINT_MATCH 64
+
+/*
+** CAPI3REF: Register A Virtual Table Implementation
+**
+** ^These routines are used to register a new [virtual table module] name.
+** ^Module names must be registered before
+** creating a new [virtual table] using the module and before using a
+** preexisting [virtual table] for the module.
+**
+** ^The module name is registered on the [database connection] specified
+** by the first parameter.  ^The name of the module is given by the 
+** second parameter.  ^The third parameter is a pointer to
+** the implementation of the [virtual table module].   ^The fourth
+** parameter is an arbitrary client data pointer that is passed through
+** into the [xCreate] and [xConnect] methods of the virtual table module
+** when a new virtual table is be being created or reinitialized.
+**
+** ^The sqlite3_create_module_v2() interface has a fifth parameter which
+** is a pointer to a destructor for the pClientData.  ^SQLite will
+** invoke the destructor function (if it is not NULL) when SQLite
+** no longer needs the pClientData pointer.  ^The sqlite3_create_module()
+** interface is equivalent to sqlite3_create_module_v2() with a NULL
+** destructor.
+*/
+SQLITE_API int sqlite3_create_module(
+  sqlite3 *db,               /* SQLite connection to register module with */
+  const char *zName,         /* Name of the module */
+  const sqlite3_module *p,   /* Methods for the module */
+  void *pClientData          /* Client data for xCreate/xConnect */
+);
+SQLITE_API int sqlite3_create_module_v2(
+  sqlite3 *db,               /* SQLite connection to register module with */
+  const char *zName,         /* Name of the module */
+  const sqlite3_module *p,   /* Methods for the module */
+  void *pClientData,         /* Client data for xCreate/xConnect */
+  void(*xDestroy)(void*)     /* Module destructor function */
+);
+
+/*
+** CAPI3REF: Virtual Table Instance Object
+** KEYWORDS: sqlite3_vtab
+**
+** Every [virtual table module] implementation uses a subclass
+** of this object to describe a particular instance
+** of the [virtual table].  Each subclass will
+** be tailored to the specific needs of the module implementation.
+** The purpose of this superclass is to define certain fields that are
+** common to all module implementations.
+**
+** ^Virtual tables methods can set an error message by assigning a
+** string obtained from [sqlite3_mprintf()] to zErrMsg.  The method should
+** take care that any prior string is freed by a call to [sqlite3_free()]
+** prior to assigning a new string to zErrMsg.  ^After the error message
+** is delivered up to the client application, the string will be automatically
+** freed by sqlite3_free() and the zErrMsg field will be zeroed.
+*/
+struct sqlite3_vtab {
+  const sqlite3_module *pModule;  /* The module for this virtual table */
+  int nRef;                       /* NO LONGER USED */
+  char *zErrMsg;                  /* Error message from sqlite3_mprintf() */
+  /* Virtual table implementations will typically add additional fields */
+};
+
+/*
+** CAPI3REF: Virtual Table Cursor Object
+** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}
+**
+** Every [virtual table module] implementation uses a subclass of the
+** following structure to describe cursors that point into the
+** [virtual table] and are used
+** to loop through the virtual table.  Cursors are created using the
+** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed
+** by the [sqlite3_module.xClose | xClose] method.  Cursors are used
+** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods
+** of the module.  Each module implementation will define
+** the content of a cursor structure to suit its own needs.
+**
+** This superclass exists in order to define fields of the cursor that
+** are common to all implementations.
+*/
+struct sqlite3_vtab_cursor {
+  sqlite3_vtab *pVtab;      /* Virtual table of this cursor */
+  /* Virtual table implementations will typically add additional fields */
+};
+
+/*
+** CAPI3REF: Declare The Schema Of A Virtual Table
+**
+** ^The [xCreate] and [xConnect] methods of a
+** [virtual table module] call this interface
+** to declare the format (the names and datatypes of the columns) of
+** the virtual tables they implement.
+*/
+SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zSQL);
+
+/*
+** CAPI3REF: Overload A Function For A Virtual Table
+**
+** ^(Virtual tables can provide alternative implementations of functions
+** using the [xFindFunction] method of the [virtual table module].  
+** But global versions of those functions
+** must exist in order to be overloaded.)^
+**
+** ^(This API makes sure a global version of a function with a particular
+** name and number of parameters exists.  If no such function exists
+** before this API is called, a new function is created.)^  ^The implementation
+** of the new function always causes an exception to be thrown.  So
+** the new function is not good for anything by itself.  Its only
+** purpose is to be a placeholder function that can be overloaded
+** by a [virtual table].
+*/
+SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
+
+/*
+** The interface to the virtual-table mechanism defined above (back up
+** to a comment remarkably similar to this one) is currently considered
+** to be experimental.  The interface might change in incompatible ways.
+** If this is a problem for you, do not use the interface at this time.
+**
+** When the virtual-table mechanism stabilizes, we will declare the
+** interface fixed, support it indefinitely, and remove this comment.
+*/
+
+/*
+** CAPI3REF: A Handle To An Open BLOB
+** KEYWORDS: {BLOB handle} {BLOB handles}
+**
+** An instance of this object represents an open BLOB on which
+** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
+** ^Objects of this type are created by [sqlite3_blob_open()]
+** and destroyed by [sqlite3_blob_close()].
+** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
+** can be used to read or write small subsections of the BLOB.
+** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
+*/
+typedef struct sqlite3_blob sqlite3_blob;
+
+/*
+** CAPI3REF: Open A BLOB For Incremental I/O
+**
+** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located
+** in row iRow, column zColumn, table zTable in database zDb;
+** in other words, the same BLOB that would be selected by:
+**
+** <pre>
+**     SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
+** </pre>)^
+**
+** ^If the flags parameter is non-zero, then the BLOB is opened for read
+** and write access. ^If it is zero, the BLOB is opened for read access.
+** ^It is not possible to open a column that is part of an index or primary 
+** key for writing. ^If [foreign key constraints] are enabled, it is 
+** not possible to open a column that is part of a [child key] for writing.
+**
+** ^Note that the database name is not the filename that contains
+** the database but rather the symbolic name of the database that
+** appears after the AS keyword when the database is connected using [ATTACH].
+** ^For the main database file, the database name is "main".
+** ^For TEMP tables, the database name is "temp".
+**
+** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is written
+** to *ppBlob. Otherwise an [error code] is returned and *ppBlob is set
+** to be a null pointer.)^
+** ^This function sets the [database connection] error code and message
+** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()] and related
+** functions. ^Note that the *ppBlob variable is always initialized in a
+** way that makes it safe to invoke [sqlite3_blob_close()] on *ppBlob
+** regardless of the success or failure of this routine.
+**
+** ^(If the row that a BLOB handle points to is modified by an
+** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
+** then the BLOB handle is marked as "expired".
+** This is true if any column of the row is changed, even a column
+** other than the one the BLOB handle is open on.)^
+** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
+** a expired BLOB handle fail with an return code of [SQLITE_ABORT].
+** ^(Changes written into a BLOB prior to the BLOB expiring are not
+** rolled back by the expiration of the BLOB.  Such changes will eventually
+** commit if the transaction continues to completion.)^
+**
+** ^Use the [sqlite3_blob_bytes()] interface to determine the size of
+** the opened blob.  ^The size of a blob may not be changed by this
+** interface.  Use the [UPDATE] SQL command to change the size of a
+** blob.
+**
+** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces
+** and the built-in [zeroblob] SQL function can be used, if desired,
+** to create an empty, zero-filled blob in which to read or write using
+** this interface.
+**
+** To avoid a resource leak, every open [BLOB handle] should eventually
+** be released by a call to [sqlite3_blob_close()].
+*/
+SQLITE_API int sqlite3_blob_open(
+  sqlite3*,
+  const char *zDb,
+  const char *zTable,
+  const char *zColumn,
+  sqlite3_int64 iRow,
+  int flags,
+  sqlite3_blob **ppBlob
+);
+
+/*
+** CAPI3REF: Close A BLOB Handle
+**
+** ^Closes an open [BLOB handle].
+**
+** ^Closing a BLOB shall cause the current transaction to commit
+** if there are no other BLOBs, no pending prepared statements, and the
+** database connection is in [autocommit mode].
+** ^If any writes were made to the BLOB, they might be held in cache
+** until the close operation if they will fit.
+**
+** ^(Closing the BLOB often forces the changes
+** out to disk and so if any I/O errors occur, they will likely occur
+** at the time when the BLOB is closed.  Any errors that occur during
+** closing are reported as a non-zero return value.)^
+**
+** ^(The BLOB is closed unconditionally.  Even if this routine returns
+** an error code, the BLOB is still closed.)^
+**
+** ^Calling this routine with a null pointer (such as would be returned
+** by a failed call to [sqlite3_blob_open()]) is a harmless no-op.
+*/
+SQLITE_API int sqlite3_blob_close(sqlite3_blob *);
+
+/*
+** CAPI3REF: Return The Size Of An Open BLOB
+**
+** ^Returns the size in bytes of the BLOB accessible via the 
+** successfully opened [BLOB handle] in its only argument.  ^The
+** incremental blob I/O routines can only read or overwriting existing
+** blob content; they cannot change the size of a blob.
+**
+** This routine only works on a [BLOB handle] which has been created
+** by a prior successful call to [sqlite3_blob_open()] and which has not
+** been closed by [sqlite3_blob_close()].  Passing any other pointer in
+** to this routine results in undefined and probably undesirable behavior.
+*/
+SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *);
+
+/*
+** CAPI3REF: Read Data From A BLOB Incrementally
+**
+** ^(This function is used to read data from an open [BLOB handle] into a
+** caller-supplied buffer. N bytes of data are copied into buffer Z
+** from the open BLOB, starting at offset iOffset.)^
+**
+** ^If offset iOffset is less than N bytes from the end of the BLOB,
+** [SQLITE_ERROR] is returned and no data is read.  ^If N or iOffset is
+** less than zero, [SQLITE_ERROR] is returned and no data is read.
+** ^The size of the blob (and hence the maximum value of N+iOffset)
+** can be determined using the [sqlite3_blob_bytes()] interface.
+**
+** ^An attempt to read from an expired [BLOB handle] fails with an
+** error code of [SQLITE_ABORT].
+**
+** ^(On success, sqlite3_blob_read() returns SQLITE_OK.
+** Otherwise, an [error code] or an [extended error code] is returned.)^
+**
+** This routine only works on a [BLOB handle] which has been created
+** by a prior successful call to [sqlite3_blob_open()] and which has not
+** been closed by [sqlite3_blob_close()].  Passing any other pointer in
+** to this routine results in undefined and probably undesirable behavior.
+**
+** See also: [sqlite3_blob_write()].
+*/
+SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
+
+/*
+** CAPI3REF: Write Data Into A BLOB Incrementally
+**
+** ^This function is used to write data into an open [BLOB handle] from a
+** caller-supplied buffer. ^N bytes of data are copied from the buffer Z
+** into the open BLOB, starting at offset iOffset.
+**
+** ^If the [BLOB handle] passed as the first argument was not opened for
+** writing (the flags parameter to [sqlite3_blob_open()] was zero),
+** this function returns [SQLITE_READONLY].
+**
+** ^This function may only modify the contents of the BLOB; it is
+** not possible to increase the size of a BLOB using this API.
+** ^If offset iOffset is less than N bytes from the end of the BLOB,
+** [SQLITE_ERROR] is returned and no data is written.  ^If N is
+** less than zero [SQLITE_ERROR] is returned and no data is written.
+** The size of the BLOB (and hence the maximum value of N+iOffset)
+** can be determined using the [sqlite3_blob_bytes()] interface.
+**
+** ^An attempt to write to an expired [BLOB handle] fails with an
+** error code of [SQLITE_ABORT].  ^Writes to the BLOB that occurred
+** before the [BLOB handle] expired are not rolled back by the
+** expiration of the handle, though of course those changes might
+** have been overwritten by the statement that expired the BLOB handle
+** or by other independent statements.
+**
+** ^(On success, sqlite3_blob_write() returns SQLITE_OK.
+** Otherwise, an  [error code] or an [extended error code] is returned.)^
+**
+** This routine only works on a [BLOB handle] which has been created
+** by a prior successful call to [sqlite3_blob_open()] and which has not
+** been closed by [sqlite3_blob_close()].  Passing any other pointer in
+** to this routine results in undefined and probably undesirable behavior.
+**
+** See also: [sqlite3_blob_read()].
+*/
+SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
+
+/*
+** CAPI3REF: Virtual File System Objects
+**
+** A virtual filesystem (VFS) is an [sqlite3_vfs] object
+** that SQLite uses to interact
+** with the underlying operating system.  Most SQLite builds come with a
+** single default VFS that is appropriate for the host computer.
+** New VFSes can be registered and existing VFSes can be unregistered.
+** The following interfaces are provided.
+**
+** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
+** ^Names are case sensitive.
+** ^Names are zero-terminated UTF-8 strings.
+** ^If there is no match, a NULL pointer is returned.
+** ^If zVfsName is NULL then the default VFS is returned.
+**
+** ^New VFSes are registered with sqlite3_vfs_register().
+** ^Each new VFS becomes the default VFS if the makeDflt flag is set.
+** ^The same VFS can be registered multiple times without injury.
+** ^To make an existing VFS into the default VFS, register it again
+** with the makeDflt flag set.  If two different VFSes with the
+** same name are registered, the behavior is undefined.  If a
+** VFS is registered with a name that is NULL or an empty string,
+** then the behavior is undefined.
+**
+** ^Unregister a VFS with the sqlite3_vfs_unregister() interface.
+** ^(If the default VFS is unregistered, another VFS is chosen as
+** the default.  The choice for the new VFS is arbitrary.)^
+*/
+SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
+SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
+SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
+
+/*
+** CAPI3REF: Mutexes
+**
+** The SQLite core uses these routines for thread
+** synchronization. Though they are intended for internal
+** use by SQLite, code that links against SQLite is
+** permitted to use any of these routines.
+**
+** The SQLite source code contains multiple implementations
+** of these mutex routines.  An appropriate implementation
+** is selected automatically at compile-time.  ^(The following
+** implementations are available in the SQLite core:
+**
+** <ul>
+** <li>   SQLITE_MUTEX_OS2
+** <li>   SQLITE_MUTEX_PTHREAD
+** <li>   SQLITE_MUTEX_W32
+** <li>   SQLITE_MUTEX_NOOP
+** </ul>)^
+**
+** ^The SQLITE_MUTEX_NOOP implementation is a set of routines
+** that does no real locking and is appropriate for use in
+** a single-threaded application.  ^The SQLITE_MUTEX_OS2,
+** SQLITE_MUTEX_PTHREAD, and SQLITE_MUTEX_W32 implementations
+** are appropriate for use on OS/2, Unix, and Windows.
+**
+** ^(If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
+** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
+** implementation is included with the library. In this case the
+** application must supply a custom mutex implementation using the
+** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
+** before calling sqlite3_initialize() or any other public sqlite3_
+** function that calls sqlite3_initialize().)^
+**
+** ^The sqlite3_mutex_alloc() routine allocates a new
+** mutex and returns a pointer to it. ^If it returns NULL
+** that means that a mutex could not be allocated.  ^SQLite
+** will unwind its stack and return an error.  ^(The argument
+** to sqlite3_mutex_alloc() is one of these integer constants:
+**
+** <ul>
+** <li>  SQLITE_MUTEX_FAST
+** <li>  SQLITE_MUTEX_RECURSIVE
+** <li>  SQLITE_MUTEX_STATIC_MASTER
+** <li>  SQLITE_MUTEX_STATIC_MEM
+** <li>  SQLITE_MUTEX_STATIC_MEM2
+** <li>  SQLITE_MUTEX_STATIC_PRNG
+** <li>  SQLITE_MUTEX_STATIC_LRU
+** <li>  SQLITE_MUTEX_STATIC_LRU2
+** </ul>)^
+**
+** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE)
+** cause sqlite3_mutex_alloc() to create
+** a new mutex.  ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
+** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
+** The mutex implementation does not need to make a distinction
+** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
+** not want to.  ^SQLite will only request a recursive mutex in
+** cases where it really needs one.  ^If a faster non-recursive mutex
+** implementation is available on the host platform, the mutex subsystem
+** might return such a mutex in response to SQLITE_MUTEX_FAST.
+**
+** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other
+** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return
+** a pointer to a static preexisting mutex.  ^Six static mutexes are
+** used by the current version of SQLite.  Future versions of SQLite
+** may add additional static mutexes.  Static mutexes are for internal
+** use by SQLite only.  Applications that use SQLite mutexes should
+** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
+** SQLITE_MUTEX_RECURSIVE.
+**
+** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
+** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
+** returns a different mutex on every call.  ^But for the static
+** mutex types, the same mutex is returned on every call that has
+** the same type number.
+**
+** ^The sqlite3_mutex_free() routine deallocates a previously
+** allocated dynamic mutex.  ^SQLite is careful to deallocate every
+** dynamic mutex that it allocates.  The dynamic mutexes must not be in
+** use when they are deallocated.  Attempting to deallocate a static
+** mutex results in undefined behavior.  ^SQLite never deallocates
+** a static mutex.
+**
+** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
+** to enter a mutex.  ^If another thread is already within the mutex,
+** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
+** SQLITE_BUSY.  ^The sqlite3_mutex_try() interface returns [SQLITE_OK]
+** upon successful entry.  ^(Mutexes created using
+** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
+** In such cases the,
+** mutex must be exited an equal number of times before another thread
+** can enter.)^  ^(If the same thread tries to enter any other
+** kind of mutex more than once, the behavior is undefined.
+** SQLite will never exhibit
+** such behavior in its own use of mutexes.)^
+**
+** ^(Some systems (for example, Windows 95) do not support the operation
+** implemented by sqlite3_mutex_try().  On those systems, sqlite3_mutex_try()
+** will always return SQLITE_BUSY.  The SQLite core only ever uses
+** sqlite3_mutex_try() as an optimization so this is acceptable behavior.)^
+**
+** ^The sqlite3_mutex_leave() routine exits a mutex that was
+** previously entered by the same thread.   ^(The behavior
+** is undefined if the mutex is not currently entered by the
+** calling thread or is not currently allocated.  SQLite will
+** never do either.)^
+**
+** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or
+** sqlite3_mutex_leave() is a NULL pointer, then all three routines
+** behave as no-ops.
+**
+** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
+*/
+SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int);
+SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*);
+SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*);
+SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*);
+SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*);
+
+/*
+** CAPI3REF: Mutex Methods Object
+**
+** An instance of this structure defines the low-level routines
+** used to allocate and use mutexes.
+**
+** Usually, the default mutex implementations provided by SQLite are
+** sufficient, however the user has the option of substituting a custom
+** implementation for specialized deployments or systems for which SQLite
+** does not provide a suitable implementation. In this case, the user
+** creates and populates an instance of this structure to pass
+** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
+** Additionally, an instance of this structure can be used as an
+** output variable when querying the system for the current mutex
+** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
+**
+** ^The xMutexInit method defined by this structure is invoked as
+** part of system initialization by the sqlite3_initialize() function.
+** ^The xMutexInit routine is called by SQLite exactly once for each
+** effective call to [sqlite3_initialize()].
+**
+** ^The xMutexEnd method defined by this structure is invoked as
+** part of system shutdown by the sqlite3_shutdown() function. The
+** implementation of this method is expected to release all outstanding
+** resources obtained by the mutex methods implementation, especially
+** those obtained by the xMutexInit method.  ^The xMutexEnd()
+** interface is invoked exactly once for each call to [sqlite3_shutdown()].
+**
+** ^(The remaining seven methods defined by this structure (xMutexAlloc,
+** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
+** xMutexNotheld) implement the following interfaces (respectively):
+**
+** <ul>
+**   <li>  [sqlite3_mutex_alloc()] </li>
+**   <li>  [sqlite3_mutex_free()] </li>
+**   <li>  [sqlite3_mutex_enter()] </li>
+**   <li>  [sqlite3_mutex_try()] </li>
+**   <li>  [sqlite3_mutex_leave()] </li>
+**   <li>  [sqlite3_mutex_held()] </li>
+**   <li>  [sqlite3_mutex_notheld()] </li>
+** </ul>)^
+**
+** The only difference is that the public sqlite3_XXX functions enumerated
+** above silently ignore any invocations that pass a NULL pointer instead
+** of a valid mutex handle. The implementations of the methods defined
+** by this structure are not required to handle this case, the results
+** of passing a NULL pointer instead of a valid mutex handle are undefined
+** (i.e. it is acceptable to provide an implementation that segfaults if
+** it is passed a NULL pointer).
+**
+** The xMutexInit() method must be threadsafe.  ^It must be harmless to
+** invoke xMutexInit() multiple times within the same process and without
+** intervening calls to xMutexEnd().  Second and subsequent calls to
+** xMutexInit() must be no-ops.
+**
+** ^xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()]
+** and its associates).  ^Similarly, xMutexAlloc() must not use SQLite memory
+** allocation for a static mutex.  ^However xMutexAlloc() may use SQLite
+** memory allocation for a fast or recursive mutex.
+**
+** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is
+** called, but only if the prior call to xMutexInit returned SQLITE_OK.
+** If xMutexInit fails in any way, it is expected to clean up after itself
+** prior to returning.
+*/
+typedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
+struct sqlite3_mutex_methods {
+  int (*xMutexInit)(void);
+  int (*xMutexEnd)(void);
+  sqlite3_mutex *(*xMutexAlloc)(int);
+  void (*xMutexFree)(sqlite3_mutex *);
+  void (*xMutexEnter)(sqlite3_mutex *);
+  int (*xMutexTry)(sqlite3_mutex *);
+  void (*xMutexLeave)(sqlite3_mutex *);
+  int (*xMutexHeld)(sqlite3_mutex *);
+  int (*xMutexNotheld)(sqlite3_mutex *);
+};
+
+/*
+** CAPI3REF: Mutex Verification Routines
+**
+** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
+** are intended for use inside assert() statements.  ^The SQLite core
+** never uses these routines except inside an assert() and applications
+** are advised to follow the lead of the core.  ^The SQLite core only
+** provides implementations for these routines when it is compiled
+** with the SQLITE_DEBUG flag.  ^External mutex implementations
+** are only required to provide these routines if SQLITE_DEBUG is
+** defined and if NDEBUG is not defined.
+**
+** ^These routines should return true if the mutex in their argument
+** is held or not held, respectively, by the calling thread.
+**
+** ^The implementation is not required to provided versions of these
+** routines that actually work. If the implementation does not provide working
+** versions of these routines, it should at least provide stubs that always
+** return true so that one does not get spurious assertion failures.
+**
+** ^If the argument to sqlite3_mutex_held() is a NULL pointer then
+** the routine should return 1.   This seems counter-intuitive since
+** clearly the mutex cannot be held if it does not exist.  But the
+** the reason the mutex does not exist is because the build is not
+** using mutexes.  And we do not want the assert() containing the
+** call to sqlite3_mutex_held() to fail, so a non-zero return is
+** the appropriate thing to do.  ^The sqlite3_mutex_notheld()
+** interface should also return 1 when given a NULL pointer.
+*/
+#ifndef NDEBUG
+SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*);
+SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*);
+#endif
+
+/*
+** CAPI3REF: Mutex Types
+**
+** The [sqlite3_mutex_alloc()] interface takes a single argument
+** which is one of these integer constants.
+**
+** The set of static mutexes may change from one SQLite release to the
+** next.  Applications that override the built-in mutex logic must be
+** prepared to accommodate additional static mutexes.
+*/
+#define SQLITE_MUTEX_FAST             0
+#define SQLITE_MUTEX_RECURSIVE        1
+#define SQLITE_MUTEX_STATIC_MASTER    2
+#define SQLITE_MUTEX_STATIC_MEM       3  /* sqlite3_malloc() */
+#define SQLITE_MUTEX_STATIC_MEM2      4  /* NOT USED */
+#define SQLITE_MUTEX_STATIC_OPEN      4  /* sqlite3BtreeOpen() */
+#define SQLITE_MUTEX_STATIC_PRNG      5  /* sqlite3_random() */
+#define SQLITE_MUTEX_STATIC_LRU       6  /* lru page list */
+#define SQLITE_MUTEX_STATIC_LRU2      7  /* lru page list */
+
+/*
+** CAPI3REF: Retrieve the mutex for a database connection
+**
+** ^This interface returns a pointer the [sqlite3_mutex] object that 
+** serializes access to the [database connection] given in the argument
+** when the [threading mode] is Serialized.
+** ^If the [threading mode] is Single-thread or Multi-thread then this
+** routine returns a NULL pointer.
+*/
+SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*);
+
+/*
+** CAPI3REF: Low-Level Control Of Database Files
+**
+** ^The [sqlite3_file_control()] interface makes a direct call to the
+** xFileControl method for the [sqlite3_io_methods] object associated
+** with a particular database identified by the second argument. ^The
+** name of the database "main" for the main database or "temp" for the
+** TEMP database, or the name that appears after the AS keyword for
+** databases that are added using the [ATTACH] SQL command.
+** ^A NULL pointer can be used in place of "main" to refer to the
+** main database file.
+** ^The third and fourth parameters to this routine
+** are passed directly through to the second and third parameters of
+** the xFileControl method.  ^The return value of the xFileControl
+** method becomes the return value of this routine.
+**
+** ^If the second parameter (zDbName) does not match the name of any
+** open database file, then SQLITE_ERROR is returned.  ^This error
+** code is not remembered and will not be recalled by [sqlite3_errcode()]
+** or [sqlite3_errmsg()].  The underlying xFileControl method might
+** also return SQLITE_ERROR.  There is no way to distinguish between
+** an incorrect zDbName and an SQLITE_ERROR return from the underlying
+** xFileControl method.
+**
+** See also: [SQLITE_FCNTL_LOCKSTATE]
+*/
+SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
+
+/*
+** CAPI3REF: Testing Interface
+**
+** ^The sqlite3_test_control() interface is used to read out internal
+** state of SQLite and to inject faults into SQLite for testing
+** purposes.  ^The first parameter is an operation code that determines
+** the number, meaning, and operation of all subsequent parameters.
+**
+** This interface is not for use by applications.  It exists solely
+** for verifying the correct operation of the SQLite library.  Depending
+** on how the SQLite library is compiled, this interface might not exist.
+**
+** The details of the operation codes, their meanings, the parameters
+** they take, and what they do are all subject to change without notice.
+** Unlike most of the SQLite API, this function is not guaranteed to
+** operate consistently from one release to the next.
+*/
+SQLITE_API int sqlite3_test_control(int op, ...);
+
+/*
+** CAPI3REF: Testing Interface Operation Codes
+**
+** These constants are the valid operation code parameters used
+** as the first argument to [sqlite3_test_control()].
+**
+** These parameters and their meanings are subject to change
+** without notice.  These values are for testing purposes only.
+** Applications should not use any of these parameters or the
+** [sqlite3_test_control()] interface.
+*/
+#define SQLITE_TESTCTRL_FIRST                    5
+#define SQLITE_TESTCTRL_PRNG_SAVE                5
+#define SQLITE_TESTCTRL_PRNG_RESTORE             6
+#define SQLITE_TESTCTRL_PRNG_RESET               7
+#define SQLITE_TESTCTRL_BITVEC_TEST              8
+#define SQLITE_TESTCTRL_FAULT_INSTALL            9
+#define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS     10
+#define SQLITE_TESTCTRL_PENDING_BYTE            11
+#define SQLITE_TESTCTRL_ASSERT                  12
+#define SQLITE_TESTCTRL_ALWAYS                  13
+#define SQLITE_TESTCTRL_RESERVE                 14
+#define SQLITE_TESTCTRL_OPTIMIZATIONS           15
+#define SQLITE_TESTCTRL_ISKEYWORD               16
+#define SQLITE_TESTCTRL_PGHDRSZ                 17
+#define SQLITE_TESTCTRL_SCRATCHMALLOC           18
+#define SQLITE_TESTCTRL_LAST                    18
+
+/*
+** CAPI3REF: SQLite Runtime Status
+**
+** ^This interface is used to retrieve runtime status information
+** about the performance of SQLite, and optionally to reset various
+** highwater marks.  ^The first argument is an integer code for
+** the specific parameter to measure.  ^(Recognized integer codes
+** are of the form [SQLITE_STATUS_MEMORY_USED | SQLITE_STATUS_...].)^
+** ^The current value of the parameter is returned into *pCurrent.
+** ^The highest recorded value is returned in *pHighwater.  ^If the
+** resetFlag is true, then the highest record value is reset after
+** *pHighwater is written.  ^(Some parameters do not record the highest
+** value.  For those parameters
+** nothing is written into *pHighwater and the resetFlag is ignored.)^
+** ^(Other parameters record only the highwater mark and not the current
+** value.  For these latter parameters nothing is written into *pCurrent.)^
+**
+** ^The sqlite3_status() routine returns SQLITE_OK on success and a
+** non-zero [error code] on failure.
+**
+** This routine is threadsafe but is not atomic.  This routine can be
+** called while other threads are running the same or different SQLite
+** interfaces.  However the values returned in *pCurrent and
+** *pHighwater reflect the status of SQLite at different points in time
+** and it is possible that another thread might change the parameter
+** in between the times when *pCurrent and *pHighwater are written.
+**
+** See also: [sqlite3_db_status()]
+*/
+SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
+
+
+/*
+** CAPI3REF: Status Parameters
+**
+** These integer constants designate various run-time status parameters
+** that can be returned by [sqlite3_status()].
+**
+** <dl>
+** ^(<dt>SQLITE_STATUS_MEMORY_USED</dt>
+** <dd>This parameter is the current amount of memory checked out
+** using [sqlite3_malloc()], either directly or indirectly.  The
+** figure includes calls made to [sqlite3_malloc()] by the application
+** and internal memory usage by the SQLite library.  Scratch memory
+** controlled by [SQLITE_CONFIG_SCRATCH] and auxiliary page-cache
+** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in
+** this parameter.  The amount returned is the sum of the allocation
+** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^
+**
+** ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt>
+** <dd>This parameter records the largest memory allocation request
+** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their
+** internal equivalents).  Only the value returned in the
+** *pHighwater parameter to [sqlite3_status()] is of interest.  
+** The value written into the *pCurrent parameter is undefined.</dd>)^
+**
+** ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt>
+** <dd>This parameter records the number of separate memory allocations.</dd>)^
+**
+** ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt>
+** <dd>This parameter returns the number of pages used out of the
+** [pagecache memory allocator] that was configured using 
+** [SQLITE_CONFIG_PAGECACHE].  The
+** value returned is in pages, not in bytes.</dd>)^
+**
+** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
+** <dd>This parameter returns the number of bytes of page cache
+** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE]
+** buffer and where forced to overflow to [sqlite3_malloc()].  The
+** returned value includes allocations that overflowed because they
+** where too large (they were larger than the "sz" parameter to
+** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because
+** no space was left in the page cache.</dd>)^
+**
+** ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt>
+** <dd>This parameter records the largest memory allocation request
+** handed to [pagecache memory allocator].  Only the value returned in the
+** *pHighwater parameter to [sqlite3_status()] is of interest.  
+** The value written into the *pCurrent parameter is undefined.</dd>)^
+**
+** ^(<dt>SQLITE_STATUS_SCRATCH_USED</dt>
+** <dd>This parameter returns the number of allocations used out of the
+** [scratch memory allocator] configured using
+** [SQLITE_CONFIG_SCRATCH].  The value returned is in allocations, not
+** in bytes.  Since a single thread may only have one scratch allocation
+** outstanding at time, this parameter also reports the number of threads
+** using scratch memory at the same time.</dd>)^
+**
+** ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
+** <dd>This parameter returns the number of bytes of scratch memory
+** allocation which could not be satisfied by the [SQLITE_CONFIG_SCRATCH]
+** buffer and where forced to overflow to [sqlite3_malloc()].  The values
+** returned include overflows because the requested allocation was too
+** larger (that is, because the requested allocation was larger than the
+** "sz" parameter to [SQLITE_CONFIG_SCRATCH]) and because no scratch buffer
+** slots were available.
+** </dd>)^
+**
+** ^(<dt>SQLITE_STATUS_SCRATCH_SIZE</dt>
+** <dd>This parameter records the largest memory allocation request
+** handed to [scratch memory allocator].  Only the value returned in the
+** *pHighwater parameter to [sqlite3_status()] is of interest.  
+** The value written into the *pCurrent parameter is undefined.</dd>)^
+**
+** ^(<dt>SQLITE_STATUS_PARSER_STACK</dt>
+** <dd>This parameter records the deepest parser stack.  It is only
+** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^
+** </dl>
+**
+** New status parameters may be added from time to time.
+*/
+#define SQLITE_STATUS_MEMORY_USED          0
+#define SQLITE_STATUS_PAGECACHE_USED       1
+#define SQLITE_STATUS_PAGECACHE_OVERFLOW   2
+#define SQLITE_STATUS_SCRATCH_USED         3
+#define SQLITE_STATUS_SCRATCH_OVERFLOW     4
+#define SQLITE_STATUS_MALLOC_SIZE          5
+#define SQLITE_STATUS_PARSER_STACK         6
+#define SQLITE_STATUS_PAGECACHE_SIZE       7
+#define SQLITE_STATUS_SCRATCH_SIZE         8
+#define SQLITE_STATUS_MALLOC_COUNT         9
+
+/*
+** CAPI3REF: Database Connection Status
+**
+** ^This interface is used to retrieve runtime status information 
+** about a single [database connection].  ^The first argument is the
+** database connection object to be interrogated.  ^The second argument
+** is an integer constant, taken from the set of
+** [SQLITE_DBSTATUS_LOOKASIDE_USED | SQLITE_DBSTATUS_*] macros, that
+** determines the parameter to interrogate.  The set of 
+** [SQLITE_DBSTATUS_LOOKASIDE_USED | SQLITE_DBSTATUS_*] macros is likely
+** to grow in future releases of SQLite.
+**
+** ^The current value of the requested parameter is written into *pCur
+** and the highest instantaneous value is written into *pHiwtr.  ^If
+** the resetFlg is true, then the highest instantaneous value is
+** reset back down to the current value.
+**
+** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a
+** non-zero [error code] on failure.
+**
+** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
+*/
+SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
+
+/*
+** CAPI3REF: Status Parameters for database connections
+**
+** These constants are the available integer "verbs" that can be passed as
+** the second argument to the [sqlite3_db_status()] interface.
+**
+** New verbs may be added in future releases of SQLite. Existing verbs
+** might be discontinued. Applications should check the return code from
+** [sqlite3_db_status()] to make sure that the call worked.
+** The [sqlite3_db_status()] interface will return a non-zero error code
+** if a discontinued or unsupported verb is invoked.
+**
+** <dl>
+** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>
+** <dd>This parameter returns the number of lookaside memory slots currently
+** checked out.</dd>)^
+**
+** ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt>
+** <dd>This parameter returns the approximate number of of bytes of heap
+** memory used by all pager caches associated with the database connection.)^
+** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0.
+**
+** ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt>
+** <dd>This parameter returns the approximate number of of bytes of heap
+** memory used to store the schema for all databases associated
+** with the connection - main, temp, and any [ATTACH]-ed databases.)^ 
+** ^The full amount of memory used by the schemas is reported, even if the
+** schema memory is shared with other database connections due to
+** [shared cache mode] being enabled.
+** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0.
+**
+** ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt>
+** <dd>This parameter returns the approximate number of of bytes of heap
+** and lookaside memory used by all prepared statements associated with
+** the database connection.)^
+** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0.
+** </dd>
+** </dl>
+*/
+#define SQLITE_DBSTATUS_LOOKASIDE_USED     0
+#define SQLITE_DBSTATUS_CACHE_USED         1
+#define SQLITE_DBSTATUS_SCHEMA_USED        2
+#define SQLITE_DBSTATUS_STMT_USED          3
+#define SQLITE_DBSTATUS_MAX                3   /* Largest defined DBSTATUS */
+
+
+/*
+** CAPI3REF: Prepared Statement Status
+**
+** ^(Each prepared statement maintains various
+** [SQLITE_STMTSTATUS_SORT | counters] that measure the number
+** of times it has performed specific operations.)^  These counters can
+** be used to monitor the performance characteristics of the prepared
+** statements.  For example, if the number of table steps greatly exceeds
+** the number of table searches or result rows, that would tend to indicate
+** that the prepared statement is using a full table scan rather than
+** an index.  
+**
+** ^(This interface is used to retrieve and reset counter values from
+** a [prepared statement].  The first argument is the prepared statement
+** object to be interrogated.  The second argument
+** is an integer code for a specific [SQLITE_STMTSTATUS_SORT | counter]
+** to be interrogated.)^
+** ^The current value of the requested counter is returned.
+** ^If the resetFlg is true, then the counter is reset to zero after this
+** interface call returns.
+**
+** See also: [sqlite3_status()] and [sqlite3_db_status()].
+*/
+SQLITE_API int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);
+
+/*
+** CAPI3REF: Status Parameters for prepared statements
+**
+** These preprocessor macros define integer codes that name counter
+** values associated with the [sqlite3_stmt_status()] interface.
+** The meanings of the various counters are as follows:
+**
+** <dl>
+** <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt>
+** <dd>^This is the number of times that SQLite has stepped forward in
+** a table as part of a full table scan.  Large numbers for this counter
+** may indicate opportunities for performance improvement through 
+** careful use of indices.</dd>
+**
+** <dt>SQLITE_STMTSTATUS_SORT</dt>
+** <dd>^This is the number of sort operations that have occurred.
+** A non-zero value in this counter may indicate an opportunity to
+** improvement performance through careful use of indices.</dd>
+**
+** <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt>
+** <dd>^This is the number of rows inserted into transient indices that
+** were created automatically in order to help joins run faster.
+** A non-zero value in this counter may indicate an opportunity to
+** improvement performance by adding permanent indices that do not
+** need to be reinitialized each time the statement is run.</dd>
+**
+** </dl>
+*/
+#define SQLITE_STMTSTATUS_FULLSCAN_STEP     1
+#define SQLITE_STMTSTATUS_SORT              2
+#define SQLITE_STMTSTATUS_AUTOINDEX         3
+
+/*
+** CAPI3REF: Custom Page Cache Object
+**
+** The sqlite3_pcache type is opaque.  It is implemented by
+** the pluggable module.  The SQLite core has no knowledge of
+** its size or internal structure and never deals with the
+** sqlite3_pcache object except by holding and passing pointers
+** to the object.
+**
+** See [sqlite3_pcache_methods] for additional information.
+*/
+typedef struct sqlite3_pcache sqlite3_pcache;
+
+/*
+** CAPI3REF: Application Defined Page Cache.
+** KEYWORDS: {page cache}
+**
+** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE], ...) interface can
+** register an alternative page cache implementation by passing in an 
+** instance of the sqlite3_pcache_methods structure.)^
+** In many applications, most of the heap memory allocated by 
+** SQLite is used for the page cache.
+** By implementing a 
+** custom page cache using this API, an application can better control
+** the amount of memory consumed by SQLite, the way in which 
+** that memory is allocated and released, and the policies used to 
+** determine exactly which parts of a database file are cached and for 
+** how long.
+**
+** The alternative page cache mechanism is an
+** extreme measure that is only needed by the most demanding applications.
+** The built-in page cache is recommended for most uses.
+**
+** ^(The contents of the sqlite3_pcache_methods structure are copied to an
+** internal buffer by SQLite within the call to [sqlite3_config].  Hence
+** the application may discard the parameter after the call to
+** [sqlite3_config()] returns.)^
+**
+** ^(The xInit() method is called once for each effective 
+** call to [sqlite3_initialize()])^
+** (usually only once during the lifetime of the process). ^(The xInit()
+** method is passed a copy of the sqlite3_pcache_methods.pArg value.)^
+** The intent of the xInit() method is to set up global data structures 
+** required by the custom page cache implementation. 
+** ^(If the xInit() method is NULL, then the 
+** built-in default page cache is used instead of the application defined
+** page cache.)^
+**
+** ^The xShutdown() method is called by [sqlite3_shutdown()].
+** It can be used to clean up 
+** any outstanding resources before process shutdown, if required.
+** ^The xShutdown() method may be NULL.
+**
+** ^SQLite automatically serializes calls to the xInit method,
+** so the xInit method need not be threadsafe.  ^The
+** xShutdown method is only called from [sqlite3_shutdown()] so it does
+** not need to be threadsafe either.  All other methods must be threadsafe
+** in multithreaded applications.
+**
+** ^SQLite will never invoke xInit() more than once without an intervening
+** call to xShutdown().
+**
+** ^SQLite invokes the xCreate() method to construct a new cache instance.
+** SQLite will typically create one cache instance for each open database file,
+** though this is not guaranteed. ^The
+** first parameter, szPage, is the size in bytes of the pages that must
+** be allocated by the cache.  ^szPage will not be a power of two.  ^szPage
+** will the page size of the database file that is to be cached plus an
+** increment (here called "R") of about 100 or 200.  SQLite will use the
+** extra R bytes on each page to store metadata about the underlying
+** database page on disk.  The value of R depends
+** on the SQLite version, the target platform, and how SQLite was compiled.
+** ^R is constant for a particular build of SQLite.  ^The second argument to
+** xCreate(), bPurgeable, is true if the cache being created will
+** be used to cache database pages of a file stored on disk, or
+** false if it is used for an in-memory database. The cache implementation
+** does not have to do anything special based with the value of bPurgeable;
+** it is purely advisory.  ^On a cache where bPurgeable is false, SQLite will
+** never invoke xUnpin() except to deliberately delete a page.
+** ^In other words, calls to xUnpin() on a cache with bPurgeable set to
+** false will always have the "discard" flag set to true.  
+** ^Hence, a cache created with bPurgeable false will
+** never contain any unpinned pages.
+**
+** ^(The xCachesize() method may be called at any time by SQLite to set the
+** suggested maximum cache-size (number of pages stored by) the cache
+** instance passed as the first argument. This is the value configured using
+** the SQLite "[PRAGMA cache_size]" command.)^  As with the bPurgeable
+** parameter, the implementation is not required to do anything with this
+** value; it is advisory only.
+**
+** The xPagecount() method must return the number of pages currently
+** stored in the cache, both pinned and unpinned.
+** 
+** The xFetch() method locates a page in the cache and returns a pointer to 
+** the page, or a NULL pointer.
+** A "page", in this context, means a buffer of szPage bytes aligned at an
+** 8-byte boundary. The page to be fetched is determined by the key. ^The
+** mimimum key value is 1.  After it has been retrieved using xFetch, the page 
+** is considered to be "pinned".
+**
+** If the requested page is already in the page cache, then the page cache
+** implementation must return a pointer to the page buffer with its content
+** intact.  If the requested page is not already in the cache, then the
+** behavior of the cache implementation should use the value of the createFlag
+** parameter to help it determined what action to take:
+**
+** <table border=1 width=85% align=center>
+** <tr><th> createFlag <th> Behaviour when page is not already in cache
+** <tr><td> 0 <td> Do not allocate a new page.  Return NULL.
+** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so.
+**                 Otherwise return NULL.
+** <tr><td> 2 <td> Make every effort to allocate a new page.  Only return
+**                 NULL if allocating a new page is effectively impossible.
+** </table>
+**
+** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1.  SQLite
+** will only use a createFlag of 2 after a prior call with a createFlag of 1
+** failed.)^  In between the to xFetch() calls, SQLite may
+** attempt to unpin one or more cache pages by spilling the content of
+** pinned pages to disk and synching the operating system disk cache.
+**
+** ^xUnpin() is called by SQLite with a pointer to a currently pinned page
+** as its second argument.  If the third parameter, discard, is non-zero,
+** then the page must be evicted from the cache.
+** ^If the discard parameter is
+** zero, then the page may be discarded or retained at the discretion of
+** page cache implementation. ^The page cache implementation
+** may choose to evict unpinned pages at any time.
+**
+** The cache must not perform any reference counting. A single 
+** call to xUnpin() unpins the page regardless of the number of prior calls 
+** to xFetch().
+**
+** The xRekey() method is used to change the key value associated with the
+** page passed as the second argument. If the cache
+** previously contains an entry associated with newKey, it must be
+** discarded. ^Any prior cache entry associated with newKey is guaranteed not
+** to be pinned.
+**
+** When SQLite calls the xTruncate() method, the cache must discard all
+** existing cache entries with page numbers (keys) greater than or equal
+** to the value of the iLimit parameter passed to xTruncate(). If any
+** of these pages are pinned, they are implicitly unpinned, meaning that
+** they can be safely discarded.
+**
+** ^The xDestroy() method is used to delete a cache allocated by xCreate().
+** All resources associated with the specified cache should be freed. ^After
+** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*]
+** handle invalid, and will not use it with any other sqlite3_pcache_methods
+** functions.
+*/
+typedef struct sqlite3_pcache_methods sqlite3_pcache_methods;
+struct sqlite3_pcache_methods {
+  void *pArg;
+  int (*xInit)(void*);
+  void (*xShutdown)(void*);
+  sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable);
+  void (*xCachesize)(sqlite3_pcache*, int nCachesize);
+  int (*xPagecount)(sqlite3_pcache*);
+  void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
+  void (*xUnpin)(sqlite3_pcache*, void*, int discard);
+  void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey);
+  void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
+  void (*xDestroy)(sqlite3_pcache*);
+};
+
+/*
+** CAPI3REF: Online Backup Object
+**
+** The sqlite3_backup object records state information about an ongoing
+** online backup operation.  ^The sqlite3_backup object is created by
+** a call to [sqlite3_backup_init()] and is destroyed by a call to
+** [sqlite3_backup_finish()].
+**
+** See Also: [Using the SQLite Online Backup API]
+*/
+typedef struct sqlite3_backup sqlite3_backup;
+
+/*
+** CAPI3REF: Online Backup API.
+**
+** The backup API copies the content of one database into another.
+** It is useful either for creating backups of databases or
+** for copying in-memory databases to or from persistent files. 
+**
+** See Also: [Using the SQLite Online Backup API]
+**
+** ^Exclusive access is required to the destination database for the 
+** duration of the operation. ^However the source database is only
+** read-locked while it is actually being read; it is not locked
+** continuously for the entire backup operation. ^Thus, the backup may be
+** performed on a live source database without preventing other users from
+** reading or writing to the source database while the backup is underway.
+** 
+** ^(To perform a backup operation: 
+**   <ol>
+**     <li><b>sqlite3_backup_init()</b> is called once to initialize the
+**         backup, 
+**     <li><b>sqlite3_backup_step()</b> is called one or more times to transfer 
+**         the data between the two databases, and finally
+**     <li><b>sqlite3_backup_finish()</b> is called to release all resources 
+**         associated with the backup operation. 
+**   </ol>)^
+** There should be exactly one call to sqlite3_backup_finish() for each
+** successful call to sqlite3_backup_init().
+**
+** <b>sqlite3_backup_init()</b>
+**
+** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the 
+** [database connection] associated with the destination database 
+** and the database name, respectively.
+** ^The database name is "main" for the main database, "temp" for the
+** temporary database, or the name specified after the AS keyword in
+** an [ATTACH] statement for an attached database.
+** ^The S and M arguments passed to 
+** sqlite3_backup_init(D,N,S,M) identify the [database connection]
+** and database name of the source database, respectively.
+** ^The source and destination [database connections] (parameters S and D)
+** must be different or else sqlite3_backup_init(D,N,S,M) will file with
+** an error.
+**
+** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is
+** returned and an error code and error message are store3d in the
+** destination [database connection] D.
+** ^The error code and message for the failed call to sqlite3_backup_init()
+** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or
+** [sqlite3_errmsg16()] functions.
+** ^A successful call to sqlite3_backup_init() returns a pointer to an
+** [sqlite3_backup] object.
+** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and
+** sqlite3_backup_finish() functions to perform the specified backup 
+** operation.
+**
+** <b>sqlite3_backup_step()</b>
+**
+** ^Function sqlite3_backup_step(B,N) will copy up to N pages between 
+** the source and destination databases specified by [sqlite3_backup] object B.
+** ^If N is negative, all remaining source pages are copied. 
+** ^If sqlite3_backup_step(B,N) successfully copies N pages and there
+** are still more pages to be copied, then the function resturns [SQLITE_OK].
+** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages
+** from source to destination, then it returns [SQLITE_DONE].
+** ^If an error occurs while running sqlite3_backup_step(B,N),
+** then an [error code] is returned. ^As well as [SQLITE_OK] and
+** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY],
+** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an
+** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code.
+**
+** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if
+** <ol>
+** <li> the destination database was opened read-only, or
+** <li> the destination database is using write-ahead-log journaling
+** and the destination and source page sizes differ, or
+** <li> The destination database is an in-memory database and the
+** destination and source page sizes differ.
+** </ol>)^
+**
+** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then
+** the [sqlite3_busy_handler | busy-handler function]
+** is invoked (if one is specified). ^If the 
+** busy-handler returns non-zero before the lock is available, then 
+** [SQLITE_BUSY] is returned to the caller. ^In this case the call to
+** sqlite3_backup_step() can be retried later. ^If the source
+** [database connection]
+** is being used to write to the source database when sqlite3_backup_step()
+** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this
+** case the call to sqlite3_backup_step() can be retried later on. ^(If
+** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or
+** [SQLITE_READONLY] is returned, then 
+** there is no point in retrying the call to sqlite3_backup_step(). These 
+** errors are considered fatal.)^  The application must accept 
+** that the backup operation has failed and pass the backup operation handle 
+** to the sqlite3_backup_finish() to release associated resources.
+**
+** ^The first call to sqlite3_backup_step() obtains an exclusive lock
+** on the destination file. ^The exclusive lock is not released until either 
+** sqlite3_backup_finish() is called or the backup operation is complete 
+** and sqlite3_backup_step() returns [SQLITE_DONE].  ^Every call to
+** sqlite3_backup_step() obtains a [shared lock] on the source database that
+** lasts for the duration of the sqlite3_backup_step() call.
+** ^Because the source database is not locked between calls to
+** sqlite3_backup_step(), the source database may be modified mid-way
+** through the backup process.  ^If the source database is modified by an
+** external process or via a database connection other than the one being
+** used by the backup operation, then the backup will be automatically
+** restarted by the next call to sqlite3_backup_step(). ^If the source 
+** database is modified by the using the same database connection as is used
+** by the backup operation, then the backup database is automatically
+** updated at the same time.
+**
+** <b>sqlite3_backup_finish()</b>
+**
+** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the 
+** application wishes to abandon the backup operation, the application
+** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish().
+** ^The sqlite3_backup_finish() interfaces releases all
+** resources associated with the [sqlite3_backup] object. 
+** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any
+** active write-transaction on the destination database is rolled back.
+** The [sqlite3_backup] object is invalid
+** and may not be used following a call to sqlite3_backup_finish().
+**
+** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no
+** sqlite3_backup_step() errors occurred, regardless or whether or not
+** sqlite3_backup_step() completed.
+** ^If an out-of-memory condition or IO error occurred during any prior
+** sqlite3_backup_step() call on the same [sqlite3_backup] object, then
+** sqlite3_backup_finish() returns the corresponding [error code].
+**
+** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step()
+** is not a permanent error and does not affect the return value of
+** sqlite3_backup_finish().
+**
+** <b>sqlite3_backup_remaining(), sqlite3_backup_pagecount()</b>
+**
+** ^Each call to sqlite3_backup_step() sets two values inside
+** the [sqlite3_backup] object: the number of pages still to be backed
+** up and the total number of pages in the source database file.
+** The sqlite3_backup_remaining() and sqlite3_backup_pagecount() interfaces
+** retrieve these two values, respectively.
+**
+** ^The values returned by these functions are only updated by
+** sqlite3_backup_step(). ^If the source database is modified during a backup
+** operation, then the values are not updated to account for any extra
+** pages that need to be updated or the size of the source database file
+** changing.
+**
+** <b>Concurrent Usage of Database Handles</b>
+**
+** ^The source [database connection] may be used by the application for other
+** purposes while a backup operation is underway or being initialized.
+** ^If SQLite is compiled and configured to support threadsafe database
+** connections, then the source database connection may be used concurrently
+** from within other threads.
+**
+** However, the application must guarantee that the destination 
+** [database connection] is not passed to any other API (by any thread) after 
+** sqlite3_backup_init() is called and before the corresponding call to
+** sqlite3_backup_finish().  SQLite does not currently check to see
+** if the application incorrectly accesses the destination [database connection]
+** and so no error code is reported, but the operations may malfunction
+** nevertheless.  Use of the destination database connection while a
+** backup is in progress might also also cause a mutex deadlock.
+**
+** If running in [shared cache mode], the application must
+** guarantee that the shared cache used by the destination database
+** is not accessed while the backup is running. In practice this means
+** that the application must guarantee that the disk file being 
+** backed up to is not accessed by any connection within the process,
+** not just the specific connection that was passed to sqlite3_backup_init().
+**
+** The [sqlite3_backup] object itself is partially threadsafe. Multiple 
+** threads may safely make multiple concurrent calls to sqlite3_backup_step().
+** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount()
+** APIs are not strictly speaking threadsafe. If they are invoked at the
+** same time as another thread is invoking sqlite3_backup_step() it is
+** possible that they return invalid values.
+*/
+SQLITE_API sqlite3_backup *sqlite3_backup_init(
+  sqlite3 *pDest,                        /* Destination database handle */
+  const char *zDestName,                 /* Destination database name */
+  sqlite3 *pSource,                      /* Source database handle */
+  const char *zSourceName                /* Source database name */
+);
+SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage);
+SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p);
+SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p);
+SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p);
+
+/*
+** CAPI3REF: Unlock Notification
+**
+** ^When running in shared-cache mode, a database operation may fail with
+** an [SQLITE_LOCKED] error if the required locks on the shared-cache or
+** individual tables within the shared-cache cannot be obtained. See
+** [SQLite Shared-Cache Mode] for a description of shared-cache locking. 
+** ^This API may be used to register a callback that SQLite will invoke 
+** when the connection currently holding the required lock relinquishes it.
+** ^This API is only available if the library was compiled with the
+** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined.
+**
+** See Also: [Using the SQLite Unlock Notification Feature].
+**
+** ^Shared-cache locks are released when a database connection concludes
+** its current transaction, either by committing it or rolling it back. 
+**
+** ^When a connection (known as the blocked connection) fails to obtain a
+** shared-cache lock and SQLITE_LOCKED is returned to the caller, the
+** identity of the database connection (the blocking connection) that
+** has locked the required resource is stored internally. ^After an 
+** application receives an SQLITE_LOCKED error, it may call the
+** sqlite3_unlock_notify() method with the blocked connection handle as 
+** the first argument to register for a callback that will be invoked
+** when the blocking connections current transaction is concluded. ^The
+** callback is invoked from within the [sqlite3_step] or [sqlite3_close]
+** call that concludes the blocking connections transaction.
+**
+** ^(If sqlite3_unlock_notify() is called in a multi-threaded application,
+** there is a chance that the blocking connection will have already
+** concluded its transaction by the time sqlite3_unlock_notify() is invoked.
+** If this happens, then the specified callback is invoked immediately,
+** from within the call to sqlite3_unlock_notify().)^
+**
+** ^If the blocked connection is attempting to obtain a write-lock on a
+** shared-cache table, and more than one other connection currently holds
+** a read-lock on the same table, then SQLite arbitrarily selects one of 
+** the other connections to use as the blocking connection.
+**
+** ^(There may be at most one unlock-notify callback registered by a 
+** blocked connection. If sqlite3_unlock_notify() is called when the
+** blocked connection already has a registered unlock-notify callback,
+** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is
+** called with a NULL pointer as its second argument, then any existing
+** unlock-notify callback is canceled. ^The blocked connections 
+** unlock-notify callback may also be canceled by closing the blocked
+** connection using [sqlite3_close()].
+**
+** The unlock-notify callback is not reentrant. If an application invokes
+** any sqlite3_xxx API functions from within an unlock-notify callback, a
+** crash or deadlock may be the result.
+**
+** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always
+** returns SQLITE_OK.
+**
+** <b>Callback Invocation Details</b>
+**
+** When an unlock-notify callback is registered, the application provides a 
+** single void* pointer that is passed to the callback when it is invoked.
+** However, the signature of the callback function allows SQLite to pass
+** it an array of void* context pointers. The first argument passed to
+** an unlock-notify callback is a pointer to an array of void* pointers,
+** and the second is the number of entries in the array.
+**
+** When a blocking connections transaction is concluded, there may be
+** more than one blocked connection that has registered for an unlock-notify
+** callback. ^If two or more such blocked connections have specified the
+** same callback function, then instead of invoking the callback function
+** multiple times, it is invoked once with the set of void* context pointers
+** specified by the blocked connections bundled together into an array.
+** This gives the application an opportunity to prioritize any actions 
+** related to the set of unblocked database connections.
+**
+** <b>Deadlock Detection</b>
+**
+** Assuming that after registering for an unlock-notify callback a 
+** database waits for the callback to be issued before taking any further
+** action (a reasonable assumption), then using this API may cause the
+** application to deadlock. For example, if connection X is waiting for
+** connection Y's transaction to be concluded, and similarly connection
+** Y is waiting on connection X's transaction, then neither connection
+** will proceed and the system may remain deadlocked indefinitely.
+**
+** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock
+** detection. ^If a given call to sqlite3_unlock_notify() would put the
+** system in a deadlocked state, then SQLITE_LOCKED is returned and no
+** unlock-notify callback is registered. The system is said to be in
+** a deadlocked state if connection A has registered for an unlock-notify
+** callback on the conclusion of connection B's transaction, and connection
+** B has itself registered for an unlock-notify callback when connection
+** A's transaction is concluded. ^Indirect deadlock is also detected, so
+** the system is also considered to be deadlocked if connection B has
+** registered for an unlock-notify callback on the conclusion of connection
+** C's transaction, where connection C is waiting on connection A. ^Any
+** number of levels of indirection are allowed.
+**
+** <b>The "DROP TABLE" Exception</b>
+**
+** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost 
+** always appropriate to call sqlite3_unlock_notify(). There is however,
+** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement,
+** SQLite checks if there are any currently executing SELECT statements
+** that belong to the same connection. If there are, SQLITE_LOCKED is
+** returned. In this case there is no "blocking connection", so invoking
+** sqlite3_unlock_notify() results in the unlock-notify callback being
+** invoked immediately. If the application then re-attempts the "DROP TABLE"
+** or "DROP INDEX" query, an infinite loop might be the result.
+**
+** One way around this problem is to check the extended error code returned
+** by an sqlite3_step() call. ^(If there is a blocking connection, then the
+** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in
+** the special "DROP TABLE/INDEX" case, the extended error code is just 
+** SQLITE_LOCKED.)^
+*/
+SQLITE_API int sqlite3_unlock_notify(
+  sqlite3 *pBlocked,                          /* Waiting connection */
+  void (*xNotify)(void **apArg, int nArg),    /* Callback function to invoke */
+  void *pNotifyArg                            /* Argument to pass to xNotify */
+);
+
+
+/*
+** CAPI3REF: String Comparison
+**
+** ^The [sqlite3_strnicmp()] API allows applications and extensions to
+** compare the contents of two buffers containing UTF-8 strings in a
+** case-independent fashion, using the same definition of case independence 
+** that SQLite uses internally when comparing identifiers.
+*/
+SQLITE_API int sqlite3_strnicmp(const char *, const char *, int);
+
+/*
+** CAPI3REF: Error Logging Interface
+**
+** ^The [sqlite3_log()] interface writes a message into the error log
+** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()].
+** ^If logging is enabled, the zFormat string and subsequent arguments are
+** used with [sqlite3_snprintf()] to generate the final output string.
+**
+** The sqlite3_log() interface is intended for use by extensions such as
+** virtual tables, collating functions, and SQL functions.  While there is
+** nothing to prevent an application from calling sqlite3_log(), doing so
+** is considered bad form.
+**
+** The zFormat string must not be NULL.
+**
+** To avoid deadlocks and other threading problems, the sqlite3_log() routine
+** will not use dynamically allocated memory.  The log message is stored in
+** a fixed-length buffer on the stack.  If the log message is longer than
+** a few hundred characters, it will be truncated to the length of the
+** buffer.
+*/
+SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...);
+
+/*
+** CAPI3REF: Write-Ahead Log Commit Hook
+**
+** ^The [sqlite3_wal_hook()] function is used to register a callback that
+** will be invoked each time a database connection commits data to a
+** [write-ahead log] (i.e. whenever a transaction is committed in
+** [journal_mode | journal_mode=WAL mode]). 
+**
+** ^The callback is invoked by SQLite after the commit has taken place and 
+** the associated write-lock on the database released, so the implementation 
+** may read, write or [checkpoint] the database as required.
+**
+** ^The first parameter passed to the callback function when it is invoked
+** is a copy of the third parameter passed to sqlite3_wal_hook() when
+** registering the callback. ^The second is a copy of the database handle.
+** ^The third parameter is the name of the database that was written to -
+** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter
+** is the number of pages currently in the write-ahead log file,
+** including those that were just committed.
+**
+** The callback function should normally return [SQLITE_OK].  ^If an error
+** code is returned, that error will propagate back up through the
+** SQLite code base to cause the statement that provoked the callback
+** to report an error, though the commit will have still occurred. If the
+** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value
+** that does not correspond to any valid SQLite error code, the results
+** are undefined.
+**
+** A single database handle may have at most a single write-ahead log callback 
+** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any
+** previously registered write-ahead log callback. ^Note that the
+** [sqlite3_wal_autocheckpoint()] interface and the
+** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will
+** those overwrite any prior [sqlite3_wal_hook()] settings.
+*/
+SQLITE_API void *sqlite3_wal_hook(
+  sqlite3*, 
+  int(*)(void *,sqlite3*,const char*,int),
+  void*
+);
+
+/*
+** CAPI3REF: Configure an auto-checkpoint
+**
+** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around
+** [sqlite3_wal_hook()] that causes any database on [database connection] D
+** to automatically [checkpoint]
+** after committing a transaction if there are N or
+** more frames in the [write-ahead log] file.  ^Passing zero or 
+** a negative value as the nFrame parameter disables automatic
+** checkpoints entirely.
+**
+** ^The callback registered by this function replaces any existing callback
+** registered using [sqlite3_wal_hook()].  ^Likewise, registering a callback
+** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism
+** configured by this function.
+**
+** ^The [wal_autocheckpoint pragma] can be used to invoke this interface
+** from SQL.
+**
+** ^Every new [database connection] defaults to having the auto-checkpoint
+** enabled with a threshold of 1000 pages.  The use of this interface
+** is only necessary if the default setting is found to be suboptimal
+** for a particular application.
+*/
+SQLITE_API int sqlite3_wal_autocheckpoint(sqlite3 *db, int N);
+
+/*
+** CAPI3REF: Checkpoint a database
+**
+** ^The [sqlite3_wal_checkpoint(D,X)] interface causes database named X
+** on [database connection] D to be [checkpointed].  ^If X is NULL or an
+** empty string, then a checkpoint is run on all databases of
+** connection D.  ^If the database connection D is not in
+** [WAL | write-ahead log mode] then this interface is a harmless no-op.
+**
+** ^The [wal_checkpoint pragma] can be used to invoke this interface
+** from SQL.  ^The [sqlite3_wal_autocheckpoint()] interface and the
+** [wal_autocheckpoint pragma] can be used to cause this interface to be
+** run whenever the WAL reaches a certain size threshold.
+*/
+SQLITE_API int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb);
+
+/*
+** Undo the hack that converts floating point types to integer for
+** builds on processors without floating point support.
+*/
+#ifdef SQLITE_OMIT_FLOATING_POINT
+# undef double
+#endif
+
+#ifdef __cplusplus
+}  /* End of the 'extern "C"' block */
+#endif
+#endif
+
+/*
+** 2010 August 30
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+*/
+
+#ifndef _SQLITE3RTREE_H_
+#define _SQLITE3RTREE_H_
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry;
+
+/*
+** Register a geometry callback named zGeom that can be used as part of an
+** R-Tree geometry query as follows:
+**
+**   SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zGeom(... params ...)
+*/
+SQLITE_API int sqlite3_rtree_geometry_callback(
+  sqlite3 *db,
+  const char *zGeom,
+  int (*xGeom)(sqlite3_rtree_geometry *, int nCoord, double *aCoord, int *pRes),
+  void *pContext
+);
+
+
+/*
+** A pointer to a structure of the following type is passed as the first
+** argument to callbacks registered using rtree_geometry_callback().
+*/
+struct sqlite3_rtree_geometry {
+  void *pContext;                 /* Copy of pContext passed to s_r_g_c() */
+  int nParam;                     /* Size of array aParam[] */
+  double *aParam;                 /* Parameters passed to SQL geom function */
+  void *pUser;                    /* Callback implementation user data */
+  void (*xDelUser)(void *);       /* Called by SQLite to clean up pUser */
+};
+
+
+#ifdef __cplusplus
+}  /* end of the 'extern "C"' block */
+#endif
+
+#endif  /* ifndef _SQLITE3RTREE_H_ */
+