Merge 3.44.2 changes into the reuse-schema-3.44 sub-branch.

FossilOrigin-Name: 2b9d5ff78f085fc465a5a7f2468ded1d15a46ce09edfe6e09bd10fe16f319757

Makefile.in

@@ -141,6 +141,7 @@ GCOV_LDFLAGS1 = -lgcov
 USE_GCOV = @USE_GCOV@
 LTCOMPILE_EXTRAS += $(GCOV_CFLAGS$(USE_GCOV))
 LTLINK_EXTRAS += $(GCOV_LDFLAGS$(USE_GCOV))
+LTCOMPILE_EXTRAS += -DSQLITE_ENABLE_SHARED_SCHEMA
 
 
 # The directory into which to store package information for
@@ -402,6 +403,7 @@ TESTSRC = \
   $(TOP)/src/test_quota.c \
   $(TOP)/src/test_rtree.c \
   $(TOP)/src/test_schema.c \
+  $(TOP)/src/test_schemapool.c \
   $(TOP)/src/test_superlock.c \
   $(TOP)/src/test_syscall.c \
   $(TOP)/src/test_tclsh.c \
@@ -466,6 +468,7 @@ TESTSRC2 = \
   $(TOP)/src/bitvec.c \
   $(TOP)/src/btree.c \
   $(TOP)/src/build.c \
+  $(TOP)/src/callback.c \
   $(TOP)/src/ctime.c \
   $(TOP)/src/date.c \
   $(TOP)/src/dbpage.c \
@@ -1137,6 +1140,8 @@ SHELL_SRC = \
 	$(TOP)/src/shell.c.in \
         $(TOP)/ext/misc/appendvfs.c \
 	$(TOP)/ext/misc/completion.c \
+        $(TOP)/ext/consio/console_io.c \
+        $(TOP)/ext/consio/console_io.h \
         $(TOP)/ext/misc/decimal.c \
         $(TOP)/ext/misc/basexx.c \
         $(TOP)/ext/misc/base64.c \

Makefile.msc

@@ -1542,6 +1542,7 @@ TESTSRC = \
   $(TOP)\src\test_quota.c \
   $(TOP)\src\test_rtree.c \
   $(TOP)\src\test_schema.c \
+  $(TOP)\src\test_schemapool.c \
   $(TOP)\src\test_superlock.c \
   $(TOP)\src\test_syscall.c \
   $(TOP)\src\test_tclsh.c \
@@ -2261,6 +2262,8 @@ keywordhash.h:	$(TOP)\tool\mkkeywordhash.c mkkeywordhash.exe
 # Source files that go into making shell.c
 SHELL_SRC = \
 	$(TOP)\src\shell.c.in \
+	$(TOP)\ext\consio\console_io.c \
+	$(TOP)\ext\consio\console_io.h \
 	$(TOP)\ext\misc\appendvfs.c \
 	$(TOP)\ext\misc\completion.c \
 	$(TOP)\ext\misc\base64.c \

VERSION

@@ -1 +1 @@
-3.44.0
+3.44.2

autoconf/tea/configure.ac

@@ -19,7 +19,7 @@ dnl	to configure the system for the local environment.
 # so that we create the export library with the dll.
 #-----------------------------------------------------------------------
 
-AC_INIT([sqlite],[3.44.0])
+AC_INIT([sqlite],[3.44.2])
 
 #--------------------------------------------------------------------
 # Call TEA_INIT as the first TEA_ macro to set up initial vars.

configure

@@ -1,6 +1,6 @@
 #! /bin/sh
 # Guess values for system-dependent variables and create Makefiles.
-# Generated by GNU Autoconf 2.69 for sqlite 3.44.0.
+# Generated by GNU Autoconf 2.69 for sqlite 3.44.2.
 #
 #
 # Copyright (C) 1992-1996, 1998-2012 Free Software Foundation, Inc.
@@ -726,8 +726,8 @@ MAKEFLAGS=
 # Identity of this package.
 PACKAGE_NAME='sqlite'
 PACKAGE_TARNAME='sqlite'
-PACKAGE_VERSION='3.44.0'
-PACKAGE_STRING='sqlite 3.44.0'
+PACKAGE_VERSION='3.44.2'
+PACKAGE_STRING='sqlite 3.44.2'
 PACKAGE_BUGREPORT=''
 PACKAGE_URL=''
 
@@ -1472,7 +1472,7 @@ if test "$ac_init_help" = "long"; then
   # Omit some internal or obsolete options to make the list less imposing.
   # This message is too long to be a string in the A/UX 3.1 sh.
   cat <<_ACEOF
-\`configure' configures sqlite 3.44.0 to adapt to many kinds of systems.
+\`configure' configures sqlite 3.44.2 to adapt to many kinds of systems.
 
 Usage: $0 [OPTION]... [VAR=VALUE]...
 
@@ -1537,7 +1537,7 @@ fi
 
 if test -n "$ac_init_help"; then
   case $ac_init_help in
-     short | recursive ) echo "Configuration of sqlite 3.44.0:";;
+     short | recursive ) echo "Configuration of sqlite 3.44.2:";;
    esac
   cat <<\_ACEOF
 
@@ -1668,7 +1668,7 @@ fi
 test -n "$ac_init_help" && exit $ac_status
 if $ac_init_version; then
   cat <<\_ACEOF
-sqlite configure 3.44.0
+sqlite configure 3.44.2
 generated by GNU Autoconf 2.69
 
 Copyright (C) 2012 Free Software Foundation, Inc.
@@ -2087,7 +2087,7 @@ cat >config.log <<_ACEOF
 This file contains any messages produced by compilers while
 running configure, to aid debugging if configure makes a mistake.
 
-It was created by sqlite $as_me 3.44.0, which was
+It was created by sqlite $as_me 3.44.2, which was
 generated by GNU Autoconf 2.69.  Invocation command line was
 
   $ $0 $@
@@ -12481,7 +12481,7 @@ cat >>$CONFIG_STATUS <<\_ACEOF || ac_write_fail=1
 # report actual input values of CONFIG_FILES etc. instead of their
 # values after options handling.
 ac_log="
-This file was extended by sqlite $as_me 3.44.0, which was
+This file was extended by sqlite $as_me 3.44.2, which was
 generated by GNU Autoconf 2.69.  Invocation command line was
 
   CONFIG_FILES    = $CONFIG_FILES
@@ -12547,7 +12547,7 @@ _ACEOF
 cat >>$CONFIG_STATUS <<_ACEOF || ac_write_fail=1
 ac_cs_config="`$as_echo "$ac_configure_args" | sed 's/^ //; s/[\\""\`\$]/\\\\&/g'`"
 ac_cs_version="\\
-sqlite config.status 3.44.0
+sqlite config.status 3.44.2
 configured by $0, generated by GNU Autoconf 2.69,
   with options \\"\$ac_cs_config\\"
 

doc/shared_schema.md

@@ -0,0 +1,142 @@
+
+Shared-Schema Mode Notes
+========================
+
+The [reuse-schema](/timeline?r=reuse-schema) branch contains changes 
+to allow SQLite connections to share schemas
+between database connections within the same process in order to save memory.
+Schemas may be shared between multiple databases attached to the same or
+distinct connection handles.
+
+Compile with -DSQLITE\_ENABLE\_SHARED\_SCHEMA in order to enable the
+shared-schema enhancement.  Enabling the shared-schema enhancement causes
+approximately a 0.1% increase in CPU cycles consumed and about a 3000-byte
+increase in the size of the library, even if shared-schema is never used.
+
+Assuming the compile-time requirements are satisfied, the shared-schema
+feature is engaged by opening the database connection using the
+sqlite3_open_v2() API with the SQLITE_OPEN_SHARED_SCHEMA
+flag specified.  The main database and any attached databases will then share
+an in-memory Schema object with any other database opened within the process
+for which: 
+
+  * the contents of the sqlite_master table, including all object names,
+    SQL statements and root pages are identical, and
+  * have the same values for the schema-cookie.
+
+Temp databases (those populated with "CREATE TEMP TABLE" and similar
+statements) never share schemas.
+
+Connections opened with the SQLITE_OPEN_SHARED_SCHEMA flag
+specified may not modify any database schema except that belonging to the
+temp database in anyway. This includes creating or dropping database 
+objects, vacuuming the database, or running ANALYZE when the
+sqlite_stat\[14\] tables do not exist.
+
+For SQLITE_OPEN_SHARED_SCHEMA connections, the
+SQLITE_DBSTATUS_SCHEMA_USED sqlite3_db_status() verb
+distributes the memory used for a shared schema object evenly between all
+database connections that share it.
+
+## The ".shared-schema" Command
+
+The shell tool on this branch contains a special dot-command to help with
+managing databases. The ".shared-schema" dot-command can be used to test
+whether or not two databases are similar enough to share in-memory schemas,
+and to fix minor problems that prevent them from doing so. To test if
+two or more database are compatible, one database is opened directly using 
+the shell tool and the following command issued:
+
+        .shared-schema check <database-1> [<database-2>]...
+
+where &lt;database-1&gt; etc. are replaced with the names of database files
+on disk. For each database specified on the command line, a single line of
+output is produced. If the database can share an in-memory schema with the
+main database opened by the shell tool, the output is of the form:
+
+        <database> is compatible
+
+Otherwise, if the database cannot share a schema with the main db, the output
+is of the form:
+
+        <database> is NOT compatible (<reason>)
+
+where &lt;reason&gt; indicates the cause of the incompatibility. &lt;reason&gt;
+is always one of the following.
+
+<ul>
+  <li> <b>objects</b> - the databases contain a different set schema objects
+  (tables, indexes, views and triggers).
+
+  <li> <b>SQL</b> - the databases contain the same set of objects, but the SQL
+  statements used to create them were not the same.
+
+  <li> <b>root pages</b> - the databases contain the same set of objects created
+  by the same SQL statements, but the root pages are not the same.
+
+  <li> <b>order of sqlite&#95;master rows</b> - the databases contain the same
+  set of objects created by the same SQL statements with the same root pages,
+  but the order of the rows in the sqlite&#95;master tables are different.
+
+  <li> <b>schema cookie</b> - the database schemas are compatible, but the 
+  schema cookie values ("PRAGMA schema&#95;version") are different.
+</ul>
+
+The final three problems in the list above can be fixed using the
+.shared-schema command. To modify such a database so that it can share a 
+schema with the main database, the following shell command is used:
+
+        .shared-schema fix <database-1> [<database-2>]...
+
+If a database can be modified so that it may share a schema with the main
+database opened by the shell tool, output is as follows:
+
+        Fixing <database>... <database> is compatible
+
+If a database does not require modification, or cannot be modified such that
+it can share a schema with the main database, the output of "fix" is identical
+to that of the "check" command.
+
+## Implementation Notes
+
+A single Schema object is never used by more than one database simultaneously,
+regardless of whether or not those databases are attached to the same or
+different database handles. Instead, a pool of schema objects is maintained 
+for each unique sqlite&#95;master-contents/schema-cookie combination
+opened within the process. Each time database schemas are required by a
+connection, for example as part of an sqlite3&#95;prepare\*(),
+sqlite3&#95;blob&#95;open() or sqlite3&#95;blob&#95;open() call, it obtains
+the minimum number of schemas required from the various schema-pools, returning
+them at the end of the call. This means that a single schema-pool only ever
+contains more than one copy of the schema if:
+
+  * Two threads require schemas from the same pool at the same time, or
+  * A single sqlite3&#95;prepare\*() call requires schemas for two or more
+    attached databases that use the same schema-pool.
+
+The size of a schema-pool never shrinks. Each schema pool always maintains 
+a number of schema objects equal to the highwater mark of schema objects
+simultaneously required by clients.
+
+This approach is preferred to allowing multiple databases to use the same
+Schema object simultaneously for three reasons:
+
+  * The Schema object is not completely read-only. For example, the 
+    Index.zIdxAff string is allocated lazily.
+  * Throughout the statement compiler, SQLite uses variables like 
+    Table.pSchema and Index.pSchema with the sqlite3SchemaToIndex() routine
+    in order to determine which attached database a Table or Index object
+    resides in. This mechanism does not work if the same Schema may be
+    used by two or more attached databases.
+  * It may be easier to modify this approach in order to allow
+    SQLITE&#95;OPEN&#95;SHARED&#95;SCHEMA connections to modify database
+    schemas, should that be required.
+
+SQLITE&#95;OPEN&#95;SHARED&#95;SCHEMA connections do not store their
+virtual-table handles in the Table.pVTable list of each table. This would not
+work, as (a) there is no guarantee that a connection will be assigned the same
+Schema object each time it requests one from a schema-pool and (b) a single
+Schema (and therefore Table) object may correspond to tables in two or more
+databases attached to a single connection. Instead, all virtual-table handles
+associated with a single database are stored in a linked-list headed at
+Db.pVTable.

ext/consio/console_io.c

@@ -0,0 +1,679 @@
+/*
+** 2023 November 4
+**
+** 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 file implements various interfaces used for console and stream I/O
+** by the SQLite project command-line tools, as explained in console_io.h .
+** Functions prefixed by "SQLITE_INTERNAL_LINKAGE" behave as described there.
+*/
+
+#ifndef SQLITE_CDECL
+# define SQLITE_CDECL
+#endif
+
+#ifndef SHELL_NO_SYSINC
+# include <stdarg.h>
+# include <string.h>
+# include <stdlib.h>
+# include <limits.h>
+# include <assert.h>
+# include "console_io.h"
+# include "sqlite3.h"
+#endif
+
+#ifndef SQLITE_CIO_NO_TRANSLATE
+# if (defined(_WIN32) || defined(WIN32)) && !SQLITE_OS_WINRT
+#  ifndef SHELL_NO_SYSINC
+#   include <io.h>
+#   include <fcntl.h>
+#   undef WIN32_LEAN_AND_MEAN
+#   define WIN32_LEAN_AND_MEAN
+#   include <windows.h>
+#  endif
+#  define CIO_WIN_WC_XLATE 1 /* Use WCHAR Windows APIs for console I/O */
+# else
+#  ifndef SHELL_NO_SYSINC
+#   include <unistd.h>
+#  endif
+#  define CIO_WIN_WC_XLATE 0 /* Use plain C library stream I/O at console */
+# endif
+#else
+# define CIO_WIN_WC_XLATE 0 /* Not exposing translation routines at all */
+#endif
+
+#if CIO_WIN_WC_XLATE
+/* Character used to represent a known-incomplete UTF-8 char group (�) */
+static WCHAR cBadGroup = 0xfffd;
+#endif
+
+#if CIO_WIN_WC_XLATE
+static HANDLE handleOfFile(FILE *pf){
+  int fileDesc = _fileno(pf);
+  union { intptr_t osfh; HANDLE fh; } fid = {
+    (fileDesc>=0)? _get_osfhandle(fileDesc) : (intptr_t)INVALID_HANDLE_VALUE
+  };
+  return fid.fh;
+}
+#endif
+
+#ifndef SQLITE_CIO_NO_TRANSLATE
+typedef struct PerStreamTags {
+# if CIO_WIN_WC_XLATE
+  HANDLE hx;
+  DWORD consMode;
+  char acIncomplete[4];
+# else
+  short reachesConsole;
+# endif
+  FILE *pf;
+} PerStreamTags;
+
+/* Define NULL-like value for things which can validly be 0. */
+# define SHELL_INVALID_FILE_PTR ((FILE *)~0)
+# if CIO_WIN_WC_XLATE
+#  define SHELL_INVALID_CONS_MODE 0xFFFF0000
+# endif
+
+# if CIO_WIN_WC_XLATE
+#  define PST_INITIALIZER { INVALID_HANDLE_VALUE, SHELL_INVALID_CONS_MODE, \
+      {0,0,0,0}, SHELL_INVALID_FILE_PTR }
+# else
+#  define PST_INITIALIZER { 0, SHELL_INVALID_FILE_PTR }
+# endif
+
+/* Quickly say whether a known output is going to the console. */
+# if CIO_WIN_WC_XLATE
+static short pstReachesConsole(PerStreamTags *ppst){
+  return (ppst->hx != INVALID_HANDLE_VALUE);
+}
+# else
+#  define pstReachesConsole(ppst) 0
+# endif
+
+# if CIO_WIN_WC_XLATE
+static void restoreConsoleArb(PerStreamTags *ppst){
+  if( pstReachesConsole(ppst) ) SetConsoleMode(ppst->hx, ppst->consMode);
+}
+# else
+#  define restoreConsoleArb(ppst)
+# endif
+
+/* Say whether FILE* appears to be a console, collect associated info. */
+static short streamOfConsole(FILE *pf, /* out */ PerStreamTags *ppst){
+# if CIO_WIN_WC_XLATE
+  short rv = 0;
+  DWORD dwCM = SHELL_INVALID_CONS_MODE;
+  HANDLE fh = handleOfFile(pf);
+  ppst->pf = pf;
+  if( INVALID_HANDLE_VALUE != fh ){
+    rv = (GetFileType(fh) == FILE_TYPE_CHAR && GetConsoleMode(fh,&dwCM));
+  }
+  ppst->hx = (rv)? fh : INVALID_HANDLE_VALUE;
+  ppst->consMode = dwCM;
+  return rv;
+# else
+  ppst->pf = pf;
+  ppst->reachesConsole = ( (short)isatty(fileno(pf)) );
+  return ppst->reachesConsole;
+# endif
+}
+
+# if CIO_WIN_WC_XLATE
+/* Define console modes for use with the Windows Console API. */
+#  define SHELL_CONI_MODE \
+  (ENABLE_ECHO_INPUT | ENABLE_INSERT_MODE | ENABLE_LINE_INPUT | 0x80 \
+  | ENABLE_QUICK_EDIT_MODE | ENABLE_EXTENDED_FLAGS | ENABLE_PROCESSED_INPUT)
+#  define SHELL_CONO_MODE (ENABLE_PROCESSED_OUTPUT | ENABLE_WRAP_AT_EOL_OUTPUT \
+  | ENABLE_VIRTUAL_TERMINAL_PROCESSING)
+# endif
+
+typedef struct ConsoleInfo {
+  PerStreamTags pstSetup[3];
+  PerStreamTags pstDesignated[3];
+  StreamsAreConsole sacSetup;
+} ConsoleInfo;
+
+static short isValidStreamInfo(PerStreamTags *ppst){
+  return (ppst->pf != SHELL_INVALID_FILE_PTR);
+}
+
+static ConsoleInfo consoleInfo = {
+  { /* pstSetup */ PST_INITIALIZER, PST_INITIALIZER, PST_INITIALIZER },
+  { /* pstDesignated[] */ PST_INITIALIZER, PST_INITIALIZER, PST_INITIALIZER },
+  SAC_NoConsole /* sacSetup */
+};
+
+SQLITE_INTERNAL_LINKAGE FILE* invalidFileStream = (FILE *)~0;
+
+# if CIO_WIN_WC_XLATE
+static void maybeSetupAsConsole(PerStreamTags *ppst, short odir){
+  if( pstReachesConsole(ppst) ){
+    DWORD cm = odir? SHELL_CONO_MODE : SHELL_CONI_MODE;
+    SetConsoleMode(ppst->hx, cm);
+  }
+}
+# else
+#  define maybeSetupAsConsole(ppst,odir)
+# endif
+
+SQLITE_INTERNAL_LINKAGE void consoleRenewSetup(void){
+# if CIO_WIN_WC_XLATE
+  int ix = 0;
+  while( ix < 6 ){
+    PerStreamTags *ppst = (ix<3)?
+      &consoleInfo.pstSetup[ix] : &consoleInfo.pstDesignated[ix-3];
+    maybeSetupAsConsole(ppst, (ix % 3)>0);
+    ++ix;
+  }
+# endif
+}
+
+SQLITE_INTERNAL_LINKAGE StreamsAreConsole
+consoleClassifySetup( FILE *pfIn, FILE *pfOut, FILE *pfErr ){
+  StreamsAreConsole rv = SAC_NoConsole;
+  FILE* apf[3] = { pfIn, pfOut, pfErr };
+  int ix;
+  for( ix = 2; ix >= 0; --ix ){
+    PerStreamTags *ppst = &consoleInfo.pstSetup[ix];
+    if( streamOfConsole(apf[ix], ppst) ){
+      rv |= (SAC_InConsole<<ix);
+    }
+    consoleInfo.pstDesignated[ix] = *ppst;
+    if( ix > 0 ) fflush(apf[ix]);
+  }
+  consoleInfo.sacSetup = rv;
+  consoleRenewSetup();
+  return rv;
+}
+
+SQLITE_INTERNAL_LINKAGE void SQLITE_CDECL consoleRestore( void ){
+# if CIO_WIN_WC_XLATE
+  static ConsoleInfo *pci = &consoleInfo;
+  if( pci->sacSetup ){
+    int ix;
+    for( ix=0; ix<3; ++ix ){
+      if( pci->sacSetup & (SAC_InConsole<<ix) ){
+        PerStreamTags *ppst = &pci->pstSetup[ix];
+        SetConsoleMode(ppst->hx, ppst->consMode);
+      }
+    }
+  }
+# endif
+}
+#endif /* !defined(SQLITE_CIO_NO_TRANSLATE) */
+
+#ifdef SQLITE_CIO_INPUT_REDIR
+/* Say whether given FILE* is among those known, via either
+** consoleClassifySetup() or set{Output,Error}Stream, as
+** readable, and return an associated PerStreamTags pointer
+** if so. Otherwise, return 0.
+*/
+static PerStreamTags * isKnownReadable(FILE *pf){
+  static PerStreamTags *apst[] = {
+    &consoleInfo.pstDesignated[0], &consoleInfo.pstSetup[0], 0
+  };
+  int ix = 0;
+  do {
+    if( apst[ix]->pf == pf ) break;
+  } while( apst[++ix] != 0 );
+  return apst[ix];
+}
+#endif
+
+#ifndef SQLITE_CIO_NO_TRANSLATE
+/* Say whether given FILE* is among those known, via either
+** consoleClassifySetup() or set{Output,Error}Stream, as
+** writable, and return an associated PerStreamTags pointer
+** if so. Otherwise, return 0.
+*/
+static PerStreamTags * isKnownWritable(FILE *pf){
+  static PerStreamTags *apst[] = {
+    &consoleInfo.pstDesignated[1], &consoleInfo.pstDesignated[2],
+    &consoleInfo.pstSetup[1], &consoleInfo.pstSetup[2], 0
+  };
+  int ix = 0;
+  do {
+    if( apst[ix]->pf == pf ) break;
+  } while( apst[++ix] != 0 );
+  return apst[ix];
+}
+
+static FILE *designateEmitStream(FILE *pf, unsigned chix){
+  FILE *rv = consoleInfo.pstDesignated[chix].pf;
+  if( pf == invalidFileStream ) return rv;
+  else{
+    /* Setting a possibly new output stream. */
+    PerStreamTags *ppst = isKnownWritable(pf);
+    if( ppst != 0 ){
+      PerStreamTags pst = *ppst;
+      consoleInfo.pstDesignated[chix] = pst;
+    }else streamOfConsole(pf, &consoleInfo.pstDesignated[chix]);
+  }
+  return rv;
+}
+
+SQLITE_INTERNAL_LINKAGE FILE *setOutputStream(FILE *pf){
+  return designateEmitStream(pf, 1);
+}
+# ifdef CONSIO_SET_ERROR_STREAM
+SQLITE_INTERNAL_LINKAGE FILE *setErrorStream(FILE *pf){
+  return designateEmitStream(pf, 2);
+}
+# endif
+#endif /* !defined(SQLITE_CIO_NO_TRANSLATE) */
+
+#ifndef SQLITE_CIO_NO_SETMODE
+# if CIO_WIN_WC_XLATE
+static void setModeFlushQ(FILE *pf, short bFlush, int mode){
+  if( bFlush ) fflush(pf);
+  _setmode(_fileno(pf), mode);
+}
+# else
+#  define setModeFlushQ(f, b, m) if(b) fflush(f)
+# endif
+
+SQLITE_INTERNAL_LINKAGE void setBinaryMode(FILE *pf, short bFlush){
+  setModeFlushQ(pf, bFlush, _O_BINARY);
+}
+SQLITE_INTERNAL_LINKAGE void setTextMode(FILE *pf, short bFlush){
+  setModeFlushQ(pf, bFlush, _O_TEXT);
+}
+# undef setModeFlushQ
+
+#else /* defined(SQLITE_CIO_NO_SETMODE) */
+# define setBinaryMode(f, bFlush) do{ if((bFlush)) fflush(f); }while(0)
+# define setTextMode(f, bFlush) do{ if((bFlush)) fflush(f); }while(0)
+#endif /* defined(SQLITE_CIO_NO_SETMODE) */
+
+#ifndef SQLITE_CIO_NO_TRANSLATE
+# if CIO_WIN_WC_XLATE
+/* Write buffer cBuf as output to stream known to reach console,
+** limited to ncTake char's. Return ncTake on success, else 0. */
+static int conZstrEmit(PerStreamTags *ppst, const char *z, int ncTake){
+  int rv = 0;
+  if( z!=NULL ){
+    int nwc = MultiByteToWideChar(CP_UTF8,0, z,ncTake, 0,0);
+    if( nwc > 0 ){
+      WCHAR *zw = sqlite3_malloc64(nwc*sizeof(WCHAR));
+      if( zw!=NULL ){
+        nwc = MultiByteToWideChar(CP_UTF8,0, z,ncTake, zw,nwc);
+        if( nwc > 0 ){
+          /* Translation from UTF-8 to UTF-16, then WCHARs out. */
+          if( WriteConsoleW(ppst->hx, zw,nwc, 0, NULL) ){
+            rv = ncTake;
+          }
+        }
+        sqlite3_free(zw);
+      }
+    }
+  }
+  return rv;
+}
+
+/* For {f,o,e}PrintfUtf8() when stream is known to reach console. */
+static int conioVmPrintf(PerStreamTags *ppst, const char *zFormat, va_list ap){
+  char *z = sqlite3_vmprintf(zFormat, ap);
+  if( z ){
+    int rv = conZstrEmit(ppst, z, (int)strlen(z));
+    sqlite3_free(z);
+    return rv;
+  }else return 0;
+}
+# endif /* CIO_WIN_WC_XLATE */
+
+# ifdef CONSIO_GET_EMIT_STREAM
+static PerStreamTags * getDesignatedEmitStream(FILE *pf, unsigned chix,
+                                               PerStreamTags *ppst){
+  PerStreamTags *rv = isKnownWritable(pf);
+  short isValid = (rv!=0)? isValidStreamInfo(rv) : 0;
+  if( rv != 0 && isValid ) return rv;
+  streamOfConsole(pf, ppst);
+  return ppst;
+}
+# endif
+
+/* Get stream info, either for designated output or error stream when
+** chix equals 1 or 2, or for an arbitrary stream when chix == 0.
+** In either case, ppst references a caller-owned PerStreamTags
+** struct which may be filled in if none of the known writable
+** streams is being held by consoleInfo. The ppf parameter is a
+** byref output when chix!=0 and a byref input when chix==0.
+ */
+static PerStreamTags *
+getEmitStreamInfo(unsigned chix, PerStreamTags *ppst,
+                  /* in/out */ FILE **ppf){
+  PerStreamTags *ppstTry;
+  FILE *pfEmit;
+  if( chix > 0 ){
+    ppstTry = &consoleInfo.pstDesignated[chix];
+    if( !isValidStreamInfo(ppstTry) ){
+      ppstTry = &consoleInfo.pstSetup[chix];
+      pfEmit = ppst->pf;
+    }else pfEmit = ppstTry->pf;
+    if( !isValidStreamInfo(ppstTry) ){
+      pfEmit = (chix > 1)? stderr : stdout;
+      ppstTry = ppst;
+      streamOfConsole(pfEmit, ppstTry);
+    }
+    *ppf = pfEmit;
+  }else{
+    ppstTry = isKnownWritable(*ppf);
+    if( ppstTry != 0 ) return ppstTry;
+    streamOfConsole(*ppf, ppst);
+    return ppst;
+  }
+  return ppstTry;
+}
+
+SQLITE_INTERNAL_LINKAGE int oPrintfUtf8(const char *zFormat, ...){
+  va_list ap;
+  int rv;
+  FILE *pfOut;
+  PerStreamTags pst = PST_INITIALIZER; /* for unknown streams */
+# if CIO_WIN_WC_XLATE
+  PerStreamTags *ppst = getEmitStreamInfo(1, &pst, &pfOut);
+# else
+  getEmitStreamInfo(1, &pst, &pfOut);
+# endif
+  assert(zFormat!=0);
+  va_start(ap, zFormat);
+# if CIO_WIN_WC_XLATE
+  if( pstReachesConsole(ppst) ){
+    rv = conioVmPrintf(ppst, zFormat, ap);
+  }else{
+# endif
+    rv = vfprintf(pfOut, zFormat, ap);
+# if CIO_WIN_WC_XLATE
+  }
+# endif
+  va_end(ap);
+  return rv;
+}
+
+SQLITE_INTERNAL_LINKAGE int ePrintfUtf8(const char *zFormat, ...){
+  va_list ap;
+  int rv;
+  FILE *pfErr;
+  PerStreamTags pst = PST_INITIALIZER; /* for unknown streams */
+# if CIO_WIN_WC_XLATE
+  PerStreamTags *ppst = getEmitStreamInfo(2, &pst, &pfErr);
+# else
+  getEmitStreamInfo(2, &pst, &pfErr);
+# endif
+  assert(zFormat!=0);
+  va_start(ap, zFormat);
+# if CIO_WIN_WC_XLATE
+  if( pstReachesConsole(ppst) ){
+    rv = conioVmPrintf(ppst, zFormat, ap);
+  }else{
+# endif
+    rv = vfprintf(pfErr, zFormat, ap);
+# if CIO_WIN_WC_XLATE
+  }
+# endif
+  va_end(ap);
+  return rv;
+}
+
+SQLITE_INTERNAL_LINKAGE int fPrintfUtf8(FILE *pfO, const char *zFormat, ...){
+  va_list ap;
+  int rv;
+  PerStreamTags pst = PST_INITIALIZER; /* for unknown streams */
+# if CIO_WIN_WC_XLATE
+  PerStreamTags *ppst = getEmitStreamInfo(0, &pst, &pfO);
+# else
+  getEmitStreamInfo(0, &pst, &pfO);
+# endif
+  assert(zFormat!=0);
+  va_start(ap, zFormat);
+# if CIO_WIN_WC_XLATE
+  if( pstReachesConsole(ppst) ){
+    maybeSetupAsConsole(ppst, 1);
+    rv = conioVmPrintf(ppst, zFormat, ap);
+    if( 0 == isKnownWritable(ppst->pf) ) restoreConsoleArb(ppst);
+  }else{
+# endif
+    rv = vfprintf(pfO, zFormat, ap);
+# if CIO_WIN_WC_XLATE
+  }
+# endif
+  va_end(ap);
+  return rv;
+}
+
+SQLITE_INTERNAL_LINKAGE int fPutsUtf8(const char *z, FILE *pfO){
+  PerStreamTags pst = PST_INITIALIZER; /* for unknown streams */
+# if CIO_WIN_WC_XLATE
+  PerStreamTags *ppst = getEmitStreamInfo(0, &pst, &pfO);
+# else
+  getEmitStreamInfo(0, &pst, &pfO);
+# endif
+  assert(z!=0);
+# if CIO_WIN_WC_XLATE
+  if( pstReachesConsole(ppst) ){
+    int rv;
+    maybeSetupAsConsole(ppst, 1);
+    rv = conZstrEmit(ppst, z, (int)strlen(z));
+    if( 0 == isKnownWritable(ppst->pf) ) restoreConsoleArb(ppst);
+    return rv;
+  }else {
+# endif
+    return (fputs(z, pfO)<0)? 0 : (int)strlen(z);
+# if CIO_WIN_WC_XLATE
+  }
+# endif
+}
+
+SQLITE_INTERNAL_LINKAGE int ePutsUtf8(const char *z){
+  FILE *pfErr;
+  PerStreamTags pst = PST_INITIALIZER; /* for unknown streams */
+# if CIO_WIN_WC_XLATE
+  PerStreamTags *ppst = getEmitStreamInfo(2, &pst, &pfErr);
+# else
+  getEmitStreamInfo(2, &pst, &pfErr);
+# endif
+  assert(z!=0);
+# if CIO_WIN_WC_XLATE
+  if( pstReachesConsole(ppst) ) return conZstrEmit(ppst, z, (int)strlen(z));
+  else {
+# endif
+    return (fputs(z, pfErr)<0)? 0 : (int)strlen(z);
+# if CIO_WIN_WC_XLATE
+  }
+# endif
+}
+
+SQLITE_INTERNAL_LINKAGE int oPutsUtf8(const char *z){
+  FILE *pfOut;
+  PerStreamTags pst = PST_INITIALIZER; /* for unknown streams */
+# if CIO_WIN_WC_XLATE
+  PerStreamTags *ppst = getEmitStreamInfo(1, &pst, &pfOut);
+# else
+  getEmitStreamInfo(1, &pst, &pfOut);
+# endif
+  assert(z!=0);
+# if CIO_WIN_WC_XLATE
+  if( pstReachesConsole(ppst) ) return conZstrEmit(ppst, z, (int)strlen(z));
+  else {
+# endif
+    return (fputs(z, pfOut)<0)? 0 : (int)strlen(z);
+# if CIO_WIN_WC_XLATE
+  }
+# endif
+}
+
+#endif /* !defined(SQLITE_CIO_NO_TRANSLATE) */
+
+#if !(defined(SQLITE_CIO_NO_UTF8SCAN) && defined(SQLITE_CIO_NO_TRANSLATE))
+/* Skip over as much z[] input char sequence as is valid UTF-8,
+** limited per nAccept char's or whole characters and containing
+** no char cn such that ((1<<cn) & ccm)!=0. On return, the
+** sequence z:return (inclusive:exclusive) is validated UTF-8.
+** Limit: nAccept>=0 => char count, nAccept<0 => character
+ */
+SQLITE_INTERNAL_LINKAGE const char*
+zSkipValidUtf8(const char *z, int nAccept, long ccm){
+  int ng = (nAccept<0)? -nAccept : 0;
+  const char *pcLimit = (nAccept>=0)? z+nAccept : 0;
+  assert(z!=0);
+  while( (pcLimit)? (z<pcLimit) : (ng-- != 0) ){
+    char c = *z;
+    if( (c & 0x80) == 0 ){
+      if( ccm != 0L && c < 0x20 && ((1L<<c) & ccm) != 0 ) return z;
+      ++z; /* ASCII */
+    }else if( (c & 0xC0) != 0xC0 ) return z; /* not a lead byte */
+    else{
+      const char *zt = z+1; /* Got lead byte, look at trail bytes.*/
+      do{
+        if( pcLimit && zt >= pcLimit ) return z;
+        else{
+          char ct = *zt++;
+          if( ct==0 || (zt-z)>4 || (ct & 0xC0)!=0x80 ){
+            /* Trailing bytes are too few, too many, or invalid. */
+            return z;
+          }
+        }
+      } while( ((c <<= 1) & 0x40) == 0x40 ); /* Eat lead byte's count. */
+      z = zt;
+    }
+  }
+  return z;
+}
+#endif /*!(defined(SQLITE_CIO_NO_UTF8SCAN)&&defined(SQLITE_CIO_NO_TRANSLATE))*/
+
+#ifndef SQLITE_CIO_NO_TRANSLATE
+
+#ifdef CONSIO_SPUTB
+SQLITE_INTERNAL_LINKAGE int
+fPutbUtf8(FILE *pfO, const char *cBuf, int nAccept){
+  assert(pfO!=0);
+# if CIO_WIN_WC_XLATE
+  PerStreamTags pst = PST_INITIALIZER; /* for unknown streams */
+  PerStreamTags *ppst = getEmitStreamInfo(0, &pst, &pfO);
+  if( pstReachesConsole(ppst) ){
+    int rv;
+    maybeSetupAsConsole(ppst, 1);
+    rv = conZstrEmit(ppst, cBuf, nAccept);
+    if( 0 == isKnownWritable(ppst->pf) ) restoreConsoleArb(ppst);
+    return rv;
+  }else {
+# endif
+    return (int)fwrite(cBuf, 1, nAccept, pfO);
+# if CIO_WIN_WC_XLATE
+  }
+# endif
+}
+#endif /* defined(CONSIO_SPUTB) */
+
+SQLITE_INTERNAL_LINKAGE int
+oPutbUtf8(const char *cBuf, int nAccept){
+  FILE *pfOut;
+  PerStreamTags pst = PST_INITIALIZER; /* for unknown streams */
+# if CIO_WIN_WC_XLATE
+  PerStreamTags *ppst = getEmitStreamInfo(1, &pst, &pfOut);
+# else
+  getEmitStreamInfo(1, &pst, &pfOut);
+# endif
+# if CIO_WIN_WC_XLATE
+  if( pstReachesConsole(ppst) ){
+    return conZstrEmit(ppst, cBuf, nAccept);
+  }else {
+# endif
+    return (int)fwrite(cBuf, 1, nAccept, pfOut);
+# if CIO_WIN_WC_XLATE
+  }
+# endif
+}
+
+# ifdef CONSIO_EPUTB
+SQLITE_INTERNAL_LINKAGE int
+ePutbUtf8(const char *cBuf, int nAccept){
+  FILE *pfErr;
+  PerStreamTags pst = PST_INITIALIZER; /* for unknown streams */
+  PerStreamTags *ppst = getEmitStreamInfo(2, &pst, &pfErr);
+#  if CIO_WIN_WC_XLATE
+  if( pstReachesConsole(ppst) ){
+    return conZstrEmit(ppst, cBuf, nAccept);
+  }else {
+#  endif
+    return (int)fwrite(cBuf, 1, nAccept, pfErr);
+#  if CIO_WIN_WC_XLATE
+  }
+#  endif
+}
+# endif /* defined(CONSIO_EPUTB) */
+
+SQLITE_INTERNAL_LINKAGE char* fGetsUtf8(char *cBuf, int ncMax, FILE *pfIn){
+  if( pfIn==0 ) pfIn = stdin;
+# if CIO_WIN_WC_XLATE
+  if( pfIn == consoleInfo.pstSetup[0].pf
+      && (consoleInfo.sacSetup & SAC_InConsole)!=0 ){
+#  if CIO_WIN_WC_XLATE==1
+#   define SHELL_GULP 150 /* Count of WCHARS to be gulped at a time */
+    WCHAR wcBuf[SHELL_GULP+1];
+    int lend = 0, noc = 0;
+    if( ncMax > 0 ) cBuf[0] = 0;
+    while( noc < ncMax-8-1 && !lend ){
+      /* There is room for at least 2 more characters and a 0-terminator. */
+      int na = (ncMax > SHELL_GULP*4+1 + noc)? SHELL_GULP : (ncMax-1 - noc)/4;
+#   undef SHELL_GULP
+      DWORD nbr = 0;
+      BOOL bRC = ReadConsoleW(consoleInfo.pstSetup[0].hx, wcBuf, na, &nbr, 0);
+      if( bRC && nbr>0 && (wcBuf[nbr-1]&0xF800)==0xD800 ){
+        /* Last WHAR read is first of a UTF-16 surrogate pair. Grab its mate. */
+        DWORD nbrx;
+        bRC &= ReadConsoleW(consoleInfo.pstSetup[0].hx, wcBuf+nbr, 1, &nbrx, 0);
+        if( bRC ) nbr += nbrx;
+      }
+      if( !bRC || (noc==0 && nbr==0) ) return 0;
+      if( nbr > 0 ){
+        int nmb = WideCharToMultiByte(CP_UTF8, 0, wcBuf,nbr,0,0,0,0);
+        if( nmb != 0 && noc+nmb <= ncMax ){
+          int iseg = noc;
+          nmb = WideCharToMultiByte(CP_UTF8, 0, wcBuf,nbr,cBuf+noc,nmb,0,0);
+          noc += nmb;
+          /* Fixup line-ends as coded by Windows for CR (or "Enter".)
+          ** This is done without regard for any setMode{Text,Binary}()
+          ** call that might have been done on the interactive input.
+          */
+          if( noc > 0 ){
+            if( cBuf[noc-1]=='\n' ){
+              lend = 1;
+              if( noc > 1 && cBuf[noc-2]=='\r' ) cBuf[--noc-1] = '\n';
+            }
+          }
+          /* Check for ^Z (anywhere in line) too, to act as EOF. */
+          while( iseg < noc ){
+            if( cBuf[iseg]=='\x1a' ){
+              noc = iseg; /* Chop ^Z and anything following. */
+              lend = 1; /* Counts as end of line too. */
+              break;
+            }
+            ++iseg;
+          }
+        }else break; /* Drop apparent garbage in. (Could assert.) */
+      }else break;
+    }
+    /* If got nothing, (after ^Z chop), must be at end-of-file. */
+    if( noc > 0 ){
+      cBuf[noc] = 0;
+      return cBuf;
+    }else return 0;
+#  endif
+  }else{
+# endif
+    return fgets(cBuf, ncMax, pfIn);
+# if CIO_WIN_WC_XLATE
+  }
+# endif
+}
+#endif /* !defined(SQLITE_CIO_NO_TRANSLATE) */
+
+#undef SHELL_INVALID_FILE_PTR

ext/consio/console_io.h

@@ -0,0 +1,280 @@
+/*
+** 2023 November 1
+**
+** 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 file exposes various interfaces used for console and other I/O
+** by the SQLite project command-line tools. These interfaces are used
+** at either source conglomeration time, compilation time, or run time.
+** This source provides for either inclusion into conglomerated,
+** "single-source" forms or separate compilation then linking.
+**
+** Platform dependencies are "hidden" here by various stratagems so
+** that, provided certain conditions are met, the programs using this
+** source or object code compiled from it need no explicit conditional
+** compilation in their source for their console and stream I/O.
+**
+** The symbols and functionality exposed here are not a public API.
+** This code may change in tandem with other project code as needed.
+**
+** When this .h file and its companion .c are directly incorporated into
+** a source conglomeration (such as shell.c), the preprocessor symbol
+** CIO_WIN_WC_XLATE is defined as 0 or 1, reflecting whether console I/O
+** translation for Windows is effected for the build.
+*/
+
+#ifndef SQLITE_INTERNAL_LINKAGE
+# define SQLITE_INTERNAL_LINKAGE extern /* external to translation unit */
+# include <stdio.h>
+#else
+# define SHELL_NO_SYSINC /* Better yet, modify mkshellc.tcl for this. */
+#endif
+
+#ifndef SQLITE3_H
+# include "sqlite3.h"
+#endif
+
+#ifndef SQLITE_CIO_NO_CLASSIFY
+
+/* Define enum for use with following function. */
+typedef enum StreamsAreConsole {
+  SAC_NoConsole = 0,
+  SAC_InConsole = 1, SAC_OutConsole = 2, SAC_ErrConsole = 4,
+  SAC_AnyConsole = 0x7
+} StreamsAreConsole;
+
+/*
+** Classify the three standard I/O streams according to whether
+** they are connected to a console attached to the process.
+**
+** Returns the bit-wise OR of SAC_{In,Out,Err}Console values,
+** or SAC_NoConsole if none of the streams reaches a console.
+**
+** This function should be called before any I/O is done with
+** the given streams. As a side-effect, the given inputs are
+** recorded so that later I/O operations on them may be done
+** differently than the C library FILE* I/O would be done,
+** iff the stream is used for the I/O functions that follow,
+** and to support the ones that use an implicit stream.
+**
+** On some platforms, stream or console mode alteration (aka
+** "Setup") may be made which is undone by consoleRestore().
+*/
+SQLITE_INTERNAL_LINKAGE StreamsAreConsole
+consoleClassifySetup( FILE *pfIn, FILE *pfOut, FILE *pfErr );
+/* A usual call for convenience: */
+#define SQLITE_STD_CONSOLE_INIT() consoleClassifySetup(stdin,stdout,stderr)
+
+/*
+** After an initial call to consoleClassifySetup(...), renew
+** the same setup it effected. (A call not after is an error.)
+** This will restore state altered by consoleRestore();
+**
+** Applications which run an inferior (child) process which
+** inherits the same I/O streams may call this function after
+** such a process exits to guard against console mode changes.
+*/
+SQLITE_INTERNAL_LINKAGE void consoleRenewSetup(void);
+
+/*
+** Undo any side-effects left by consoleClassifySetup(...).
+**
+** This should be called after consoleClassifySetup() and
+** before the process terminates normally. It is suitable
+** for use with the atexit() C library procedure. After
+** this call, no console I/O should be done until one of
+** console{Classify or Renew}Setup(...) is called again.
+**
+** Applications which run an inferior (child) process that
+** inherits the same I/O streams might call this procedure
+** before so that said process will have a console setup
+** however users have configured it or come to expect.
+*/
+SQLITE_INTERNAL_LINKAGE void SQLITE_CDECL consoleRestore( void );
+
+#else /* defined(SQLITE_CIO_NO_CLASSIFY) */
+# define consoleClassifySetup(i,o,e)
+# define consoleRenewSetup()
+# define consoleRestore()
+#endif /* defined(SQLITE_CIO_NO_CLASSIFY) */
+
+#ifndef SQLITE_CIO_NO_REDIRECT
+/*
+** Set stream to be used for the functions below which write
+** to "the designated X stream", where X is Output or Error.
+** Returns the previous value.
+**
+** Alternatively, pass the special value, invalidFileStream,
+** to get the designated stream value without setting it.
+**
+** Before the designated streams are set, they default to
+** those passed to consoleClassifySetup(...), and before
+** that is called they default to stdout and stderr.
+**
+** It is error to close a stream so designated, then, without
+** designating another, use the corresponding {o,e}Emit(...).
+*/
+SQLITE_INTERNAL_LINKAGE FILE *invalidFileStream;
+SQLITE_INTERNAL_LINKAGE FILE *setOutputStream(FILE *pf);
+# ifdef CONSIO_SET_ERROR_STREAM
+SQLITE_INTERNAL_LINKAGE FILE *setErrorStream(FILE *pf);
+# endif
+#else
+# define setOutputStream(pf)
+# define setErrorStream(pf)
+#endif /* !defined(SQLITE_CIO_NO_REDIRECT) */
+
+#ifndef SQLITE_CIO_NO_TRANSLATE
+/*
+** Emit output like fprintf(). If the output is going to the
+** console and translation from UTF-8 is necessary, perform
+** the needed translation. Otherwise, write formatted output
+** to the provided stream almost as-is, possibly with newline
+** translation as specified by set{Binary,Text}Mode().
+*/
+SQLITE_INTERNAL_LINKAGE int fPrintfUtf8(FILE *pfO, const char *zFormat, ...);
+/* Like fPrintfUtf8 except stream is always the designated output. */
+SQLITE_INTERNAL_LINKAGE int oPrintfUtf8(const char *zFormat, ...);
+/* Like fPrintfUtf8 except stream is always the designated error. */
+SQLITE_INTERNAL_LINKAGE int ePrintfUtf8(const char *zFormat, ...);
+
+/*
+** Emit output like fputs(). If the output is going to the
+** console and translation from UTF-8 is necessary, perform
+** the needed translation. Otherwise, write given text to the
+** provided stream almost as-is, possibly with newline
+** translation as specified by set{Binary,Text}Mode().
+*/
+SQLITE_INTERNAL_LINKAGE int fPutsUtf8(const char *z, FILE *pfO);
+/* Like fPutsUtf8 except stream is always the designated output. */
+SQLITE_INTERNAL_LINKAGE int oPutsUtf8(const char *z);
+/* Like fPutsUtf8 except stream is always the designated error. */
+SQLITE_INTERNAL_LINKAGE int ePutsUtf8(const char *z);
+
+/*
+** Emit output like fPutsUtf8(), except that the length of the
+** accepted char or character sequence is limited by nAccept.
+**
+** Returns the number of accepted char values.
+*/
+#ifdef CONSIO_SPUTB
+SQLITE_INTERNAL_LINKAGE int
+fPutbUtf8(FILE *pfOut, const char *cBuf, int nAccept);
+#endif
+/* Like fPutbUtf8 except stream is always the designated output. */
+SQLITE_INTERNAL_LINKAGE int
+oPutbUtf8(const char *cBuf, int nAccept);
+/* Like fPutbUtf8 except stream is always the designated error. */
+#ifdef CONSIO_EPUTB
+SQLITE_INTERNAL_LINKAGE int
+ePutbUtf8(const char *cBuf, int nAccept);
+#endif
+
+/*
+** Collect input like fgets(...) with special provisions for input
+** from the console on platforms that require same. Defers to the
+** C library fgets() when input is not from the console. Newline
+** translation may be done as set by set{Binary,Text}Mode(). As a
+** convenience, pfIn==NULL is treated as stdin.
+*/
+SQLITE_INTERNAL_LINKAGE char* fGetsUtf8(char *cBuf, int ncMax, FILE *pfIn);
+/* Like fGetsUtf8 except stream is always the designated input. */
+/* SQLITE_INTERNAL_LINKAGE char* iGetsUtf8(char *cBuf, int ncMax); */
+
+#endif /* !defined(SQLITE_CIO_NO_TRANSLATE) */
+
+#ifndef SQLITE_CIO_NO_SETMODE
+/*
+** Set given stream for binary mode, where newline translation is
+** not done, or for text mode where, for some platforms, newlines
+** are translated to the platform's conventional char sequence.
+** If bFlush true, flush the stream.
+**
+** An additional side-effect is that if the stream is one passed
+** to consoleClassifySetup() as an output, it is flushed first.
+**
+** Note that binary/text mode has no effect on console I/O
+** translation. On all platforms, newline to the console starts
+** a new line and CR,LF chars from the console become a newline.
+*/
+SQLITE_INTERNAL_LINKAGE void setBinaryMode(FILE *, short bFlush);
+SQLITE_INTERNAL_LINKAGE void setTextMode(FILE *, short bFlush);
+#endif
+
+#ifdef SQLITE_CIO_PROMPTED_IN
+typedef struct Prompts {
+  int numPrompts;
+  const char **azPrompts;
+} Prompts;
+
+/*
+** Macros for use of a line editor.
+**
+** The following macros define operations involving use of a
+** line-editing library or simple console interaction.
+** A "T" argument is a text (char *) buffer or filename.
+** A "N" argument is an integer.
+**
+** SHELL_ADD_HISTORY(T) // Record text as line(s) of history.
+** SHELL_READ_HISTORY(T) // Read history from file named by T.
+** SHELL_WRITE_HISTORY(T) // Write history to file named by T.
+** SHELL_STIFLE_HISTORY(N) // Limit history to N entries.
+**
+** A console program which does interactive console input is
+** expected to call:
+** SHELL_READ_HISTORY(T) before collecting such input;
+** SHELL_ADD_HISTORY(T) as record-worthy input is taken;
+** SHELL_STIFLE_HISTORY(N) after console input ceases; then
+** SHELL_WRITE_HISTORY(T) before the program exits.
+*/
+
+/*
+** Retrieve a single line of input text from an input stream.
+**
+** If pfIn is the input stream passed to consoleClassifySetup(),
+** and azPrompt is not NULL, then a prompt is issued before the
+** line is collected, as selected by the isContinuation flag.
+** Array azPrompt[{0,1}] holds the {main,continuation} prompt.
+**
+** If zBufPrior is not NULL then it is a buffer from a prior
+** call to this routine that can be reused, or will be freed.
+**
+** The result is stored in space obtained from malloc() and
+** must either be freed by the caller or else passed back to
+** this function as zBufPrior for reuse.
+**
+** This function may call upon services of a line-editing
+** library to interactively collect line edited input.
+*/
+SQLITE_INTERNAL_LINKAGE char *
+shellGetLine(FILE *pfIn, char *zBufPrior, int nLen,
+             short isContinuation, Prompts azPrompt);
+#endif /* defined(SQLITE_CIO_PROMPTED_IN) */
+/*
+** TBD: Define an interface for application(s) to generate
+** completion candidates for use by the line-editor.
+**
+** This may be premature; the CLI is the only application
+** that does this. Yet, getting line-editing melded into
+** console I/O is desirable because a line-editing library
+** may have to establish console operating mode, possibly
+** in a way that interferes with the above functionality.
+*/
+
+#if !(defined(SQLITE_CIO_NO_UTF8SCAN)&&defined(SQLITE_CIO_NO_TRANSLATE))
+/* Skip over as much z[] input char sequence as is valid UTF-8,
+** limited per nAccept char's or whole characters and containing
+** no char cn such that ((1<<cn) & ccm)!=0. On return, the
+** sequence z:return (inclusive:exclusive) is validated UTF-8.
+** Limit: nAccept>=0 => char count, nAccept<0 => character
+ */
+SQLITE_INTERNAL_LINKAGE const char*
+zSkipValidUtf8(const char *z, int nAccept, long ccm);
+
+#endif

ext/fts5/fts5_hash.c

@@ -432,10 +432,8 @@ static Fts5HashEntry *fts5HashEntryMerge(
 }
 
 /*
-** Extract all tokens from hash table iHash and link them into a list
-** in sorted order. The hash table is cleared before returning. It is
-** the responsibility of the caller to free the elements of the returned
-** list.
+** Link all tokens from hash table iHash into a list in sorted order. The
+** tokens are not removed from the hash table.
 */
 static int fts5HashEntrySort(
   Fts5Hash *pHash, 

ext/fts5/fts5_index.c

@@ -2719,6 +2719,14 @@ static void fts5SegIterHashInit(
         pLeaf->p = (u8*)pList;
       }
     }
+
+    /* The call to sqlite3Fts5HashScanInit() causes the hash table to
+    ** fill the size field of all existing position lists. This means they
+    ** can no longer be appended to. Since the only scenario in which they
+    ** can be appended to is if the previous operation on this table was
+    ** a DELETE, by clearing the Fts5Index.bDelete flag we can avoid this
+    ** possibility altogether.  */
+    p->bDelete = 0;
   }else{
     p->rc = sqlite3Fts5HashQuery(p->pHash, sizeof(Fts5Data), 
         (const char*)pTerm, nTerm, (void**)&pLeaf, &nList
@@ -4396,7 +4404,7 @@ static void fts5WriteAppendPoslistData(
   const u8 *a = aData;
   int n = nData;
   
-  assert( p->pConfig->pgsz>0 );
+  assert( p->pConfig->pgsz>0 || p->rc!=SQLITE_OK );
   while( p->rc==SQLITE_OK 
      && (pPage->buf.n + pPage->pgidx.n + n)>=p->pConfig->pgsz 
   ){
@@ -5129,18 +5137,24 @@ static void fts5DoSecureDelete(
 
   iOff = iStart;
 
-  /* Set variable bLastInDoclist to true if this entry happens to be
-  ** the last rowid in the doclist for its term.  */
+  /* If the position-list for the entry being removed flows over past
+  ** the end of this page, delete the portion of the position-list on the
+  ** next page and beyond.
+  **
+  ** Set variable bLastInDoclist to true if this entry happens 
+  ** to be the last rowid in the doclist for its term.  */
+  if( iNextOff>=iPgIdx ){
+    int pgno = pSeg->iLeafPgno+1;
+    fts5SecureDeleteOverflow(p, pSeg->pSeg, pgno, &bLastInDoclist);
+    iNextOff = iPgIdx;
+  }
+
   if( pSeg->bDel==0 ){
-    if( iNextOff>=iPgIdx ){
-      int pgno = pSeg->iLeafPgno+1;
-      fts5SecureDeleteOverflow(p, pSeg->pSeg, pgno, &bLastInDoclist);
-      iNextOff = iPgIdx;
-    }else{
+    if( iNextOff!=iPgIdx ){
       /* Loop through the page-footer. If iNextOff (offset of the
       ** entry following the one we are removing) is equal to the 
       ** offset of a key on this page, then the entry is the last 
-      ** in its doclist.  */
+      ** in its doclist. */
       int iKeyOff = 0;
       for(iIdx=0; iIdx<nIdx; /* no-op */){
         u32 iVal = 0;
@@ -5656,8 +5670,9 @@ int sqlite3Fts5IndexOptimize(Fts5Index *p){
 
   assert( p->rc==SQLITE_OK );
   fts5IndexFlush(p);
-  assert( p->nContentlessDelete==0 );
+  assert( p->rc!=SQLITE_OK || p->nContentlessDelete==0 );
   pStruct = fts5StructureRead(p);
+  assert( p->rc!=SQLITE_OK || pStruct!=0 );
   fts5StructureInvalidate(p);
 
   if( pStruct ){
@@ -6204,7 +6219,7 @@ int sqlite3Fts5IndexBeginWrite(Fts5Index *p, int bDelete, i64 iRowid){
   /* Flush the hash table to disk if required */
   if( iRowid<p->iWriteRowid 
    || (iRowid==p->iWriteRowid && p->bDelete==0)
-   || (p->nPendingData > p->pConfig->nHashSize) 
+   || (p->nPendingData > p->pConfig->nHashSize)
   ){
     fts5IndexFlush(p);
   }

ext/fts5/test/fts5corrupt5.test

@@ -880,6 +880,91 @@ do_catchsql_test 5.4 {
   UPDATE t1 SET content=randomblob(500);
 } {1 {database disk image is malformed}}
 
+#-------------------------------------------------------------------------
+reset_db
+do_test 6.0 {
+  sqlite3 db {}
+  db deserialize [decode_hexdb {
+.open --hexdb
+| size 32768 pagesize 4096 filename crash-42fa37b694d45a.db
+| page 1 offset 0
+|      0: 53 51 4c 69 74 65 20 66 6f 72 6d 61 74 20 33 00   SQLite format 3.
+|     16: 10 00 01 01 00 40 20 20 00 00 00 00 00 00 00 07   .....@  ........
+|     96: 00 00 00 00 0d 00 00 00 07 0d d2 00 0f c4 0f 6d   ...............m
+|    112: 0f 02 0e ab 0e 4e 0d f6 0d d2 00 00 00 00 00 00   .....N..........
+|   3536: 00 00 22 07 06 17 11 11 01 31 74 61 62 6c 65 74   .........1tablet
+|   3552: 32 74 32 07 43 52 45 41 54 45 20 54 41 42 4c 45   2t2.CREATE TABLE
+|   3568: 20 74 32 28 78 29 56 06 06 17 1f 1f 01 7d 74 61    t2(x)V.......ta
+|   3584: 62 6c 65 74 31 5f 63 6f 6e 66 69 67 74 31 5f 63   blet1_configt1_c
+|   3600: 6f 6e 66 69 67 06 43 52 45 41 54 45 20 54 41 42   onfig.CREATE TAB
+|   3616: 4c 45 20 27 74 31 5f 63 6f 6e 66 69 67 27 28 6b   LE 't1_config'(k
+|   3632: 20 50 52 49 4d 41 52 59 20 4b 45 59 2c 20 76 29    PRIMARY KEY, v)
+|   3648: 20 57 49 54 48 4f 55 54 20 52 4f 57 49 44 5b 05    WITHOUT ROWID[.
+|   3664: 07 17 21 21 01 81 01 74 61 62 6c 65 74 31 5f 64   ..!!...tablet1_d
+|   3680: 6f 63 73 69 7a 65 74 31 5f 64 6f 63 73 69 7a 65   ocsizet1_docsize
+|   3696: 05 43 52 45 41 54 45 20 54 41 42 4c 45 20 27 74   .CREATE TABLE 't
+|   3712: 31 5f 64 6f 63 73 69 7a 65 27 28 69 64 20 49 4e   1_docsize'(id IN
+|   3728: 54 45 47 45 52 20 50 52 49 4d 41 52 59 20 4b 45   TEGER PRIMARY KE
+|   3744: 59 2c 20 73 7a 20 42 4c 4f 42 29 55 04 06 17 21   Y, sz BLOB)U...!
+|   3760: 21 01 77 74 61 62 6c 65 74 31 5f 63 6f 6e 74 65   !.wtablet1_conte
+|   3776: 6e 74 74 31 5f 63 6f 6e 74 65 6e 74 04 43 52 45   ntt1_content.CRE
+|   3792: 41 54 45 20 54 41 42 4c 45 20 27 74 31 5f 63 6f   ATE TABLE 't1_co
+|   3808: 6e 74 65 6e 74 27 28 69 64 20 49 4e 54 45 47 45   ntent'(id INTEGE
+|   3824: 52 20 50 52 49 4d 41 52 49 20 4b 45 59 2c 20 63   R PRIMARI KEY, c
+|   3840: 30 29 69 03 07 17 19 19 01 81 2d 74 61 62 6c 65   0)i.......-table
+|   3856: 74 31 5f 69 64 78 74 31 5f 69 64 78 03 43 52 45   t1_idxt1_idx.CRE
+|   3872: 41 54 45 20 54 41 42 4c 45 20 27 74 31 5f 69 64   ATE TABLE 't1_id
+|   3888: 78 27 28 73 65 67 69 64 2c 20 74 65 72 6d 2c 20   x'(segid, term, 
+|   3904: 70 67 6e 6f 2c 20 50 52 49 4d 41 52 59 20 4b 45   pgno, PRIMARY KE
+|   3920: 59 28 73 65 67 69 64 2c 20 74 65 72 6d 29 29 20   Y(segid, term)) 
+|   3936: 57 49 54 48 4f 55 54 20 52 4f 57 49 44 55 02 07   WITHOUT ROWIDU..
+|   3952: 17 1b 1b 01 81 01 74 61 62 6c 65 74 31 5f 64 61   ......tablet1_da
+|   3968: 74 61 74 31 5f 64 61 74 61 02 43 52 45 41 54 45   tat1_data.CREATE
+|   3984: 20 54 41 42 4c 45 20 27 74 31 5f 64 61 74 61 27    TABLE 't1_data'
+|   4000: 28 69 64 20 49 4e 54 45 47 45 52 20 50 52 49 4d   (id INTEGER PRIM
+|   4016: 41 52 b9 20 4b 45 59 2c 20 62 6c 6f 63 6b 20 42   AR. KEY, block B
+|   4032: 4c 4f 42 29 3a 01 06 17 11 11 08 63 74 61 62 6c   LOB):......ctabl
+|   4048: 65 74 31 74 31 43 52 45 41 54 45 20 56 49 52 54   et1t1CREATE VIRT
+|   4064: 55 41 4c 20 54 41 42 4c 45 20 74 31 20 55 53 49   UAL TABLE t1 USI
+|   4080: 4e 47 20 66 74 73 35 28 63 6f 6e 74 65 6e 74 29   NG fts5(content)
+| page 2 offset 4096
+|      0: 0d 00 00 00 03 0f bd 00 0f e8 0f ef 0f bd f0 00   ................
+|     16: 00 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00   ................
+|   4016: 00 00 00 00 00 00 00 00 00 00 00 00 00 24 84 80   .............$..
+|   4032: 80 80 80 01 03 00 4e 00 10 00 1e 06 30 61 62 61   ......N.....0aba
+|   4048: 63 6c 01 02 02 04 02 66 74 02 5f 02 04 04 6e 64   cl.....ft._...nd
+|   4064: 6f 6e 02 02 02 04 0a 07 05 01 03 00 10 03 03 0f   on..............
+|   4080: 0a 03 00 24 00 00 00 00 01 01 01 00 01 01 01 11   ...$............
+| page 3 offset 8192
+|      0: 0a 00 00 00 01 0f 00 01 00 00 00 00 00 00 00 00   ................
+|   4080: 00 00 00 00 00 00 00 00 00 00 05 04 09 0c 01 02   ................
+| page 4 offset 12288
+|      0: 0d 00 00 00 03 0f e0 00 0f f6 0f ec 0f e0 00 00   ................
+|   4064: 0a 03 03 00 1b 61 62 61 6e 64 6f 6e 08 02 03 00   .....abandon....
+|   4080: 17 61 62 61 66 74 08 01 03 00 17 61 62 61 63 6b   .abaft.....aback
+| page 5 offset 16384
+|      0: 0d 00 00 00 03 0f ee 00 0f fa 0f 00 00 00 00 00   ................
+|   4064: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 04 03   ................
+|   4080: 03 00 0e 01 04 02 03 00 0e 01 04 01 03 00 0e 01   ................
+| page 6 offset 20480
+|      0: 0a 00 00 00 01 0f f4 00 0f f4 00 00 00 00 00 00   ................
+|   4080: 00 00 00 00 0b 03 1b 01 76 65 72 73 69 6f 6e 04   ........version.
+| page 7 offset 24576
+|      0: 0d 00 00 10 03 0f d6 00 0f 00 00 00 00 00 00 00   ................
+|   4048: 00 00 00 00 00 00 09 03 02 1b 72 65 62 75 69 6c   ..........rebuil
+|   4064: 64 11 02 02 2b 69 6e 74 65 67 72 69 74 79 2d 63   d...+integrity-c
+|   4080: 68 65 63 6b 0a 01 02 1d 6f 70 74 69 6d 00 00 00   heck....optim...
+| page 8 offset 28672
+|      0: 00 00 01 00 00 00 00 00 00 00 00 00 00 00 00 00   ................
+| end crash-42fa37b694d45a.db
+}]} {}
+
+do_execsql_test 6.1 {
+  INSERT INTO t1(t1,rank) VALUES('secure-delete',1);
+}
+do_catchsql_test 6.2 {
+  UPDATE t1 SET content=randomblob(500) WHERE t1;
+} {1 {constraint failed}}
 
 sqlite3_fts5_may_be_corrupt 0
 finish_test

ext/fts5/test/fts5faultG.test

@@ -46,5 +46,31 @@ do_faultsim_test 1 -faults oom* -prep {
   faultsim_test_result {0 {}}
 }
 
+reset_db
+do_execsql_test 2.0 {
+  CREATE VIRTUAL TABLE t1 USING fts5(a, content=, contentless_delete=1);
+  BEGIN;
+    INSERT INTO t1 VALUES('here''s some text');
+    INSERT INTO t1 VALUES('useful stuff, text');
+    INSERT INTO t1 VALUES('what would we do without text!'); 
+  COMMIT;
+}
+faultsim_save_and_close
+do_faultsim_test 2 -faults oom* -prep { 
+  faultsim_restore_and_reopen
+  execsql {
+    BEGIN;
+      DELETE FROM t1 WHERE rowid=2;
+  }
+} -body {
+  execsql {
+    INSERT INTO t1(t1) VALUES('optimize');
+  }
+} -test {
+  faultsim_integrity_check
+  faultsim_test_result {0 {}}
+}
+
+
 
 finish_test

ext/fts5/test/fts5prefix2.test

@@ -52,6 +52,36 @@ do_execsql_test 2.1 {
   SELECT * FROM t2('to*');
 } {top to tommy}
 
+#-------------------------------------------------------------------------
+
+foreach {tn newrowid} {
+  1   122
+  2   123
+  3   124
+} {
+  reset_db
+  do_execsql_test 3.$tn.0 {
+    CREATE VIRTUAL TABLE t12 USING fts5(x);
+    INSERT INTO t12(rowid, x) VALUES(123, 'wwww');
+  }
+  do_execsql_test 3.$tn.1 {
+    BEGIN;
+    DELETE FROM t12 WHERE rowid=123;
+    SELECT * FROM t12('wwww*');
+    INSERT INTO t12(rowid, x) VALUES($newrowid, 'wwww');
+    SELECT * FROM t12('wwww*');
+    END;
+  } {wwww}
+  do_execsql_test 3.$tn.2 {
+    INSERT INTO t12(t12) VALUES('integrity-check');
+  }
+  do_execsql_test 3.$tn.3 {
+    SELECT rowid FROM t12('wwww*');
+  } $newrowid
+}
+
+finish_test
+
 
 
 finish_test

ext/fts5/test/fts5secure8.test

@@ -0,0 +1,51 @@
+# 2023 Nov 23
+#
+# 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.
+#
+#*************************************************************************
+#
+
+source [file join [file dirname [info script]] fts5_common.tcl]
+ifcapable !fts5 { finish_test ; return }
+set ::testprefix fts5secure8
+
+proc sql_repeat {txt n} {
+  string repeat $txt $n
+}
+db func repeat sql_repeat
+
+do_execsql_test 1.0 {
+  CREATE VIRTUAL TABLE ft USING fts5(x);
+
+  INSERT INTO ft(ft, rank) VALUES('pgsz', 64);
+
+  INSERT INTO ft(rowid, x) VALUES(100, 'hello world');
+  INSERT INTO ft(rowid, x) VALUES(200, 'one day');
+
+  BEGIN;
+    INSERT INTO ft(rowid, x) VALUES(45, 'one two three');
+    UPDATE ft SET x = repeat('hello world ', 500) WHERE rowid=100;
+  COMMIT
+}
+
+do_execsql_test 1.1 {
+  INSERT INTO ft(ft, rank) VALUES('secure-delete', 1);
+  DELETE FROM ft WHERE rowid=100;
+}
+
+do_execsql_test 1.2 {
+  PRAGMA integrity_check;
+} {ok}
+
+
+
+
+
+finish_test
+
+

ext/wasm/EXPORTED_FUNCTIONS.fiddle

@@ -1,10 +1,7 @@
+_fiddle_exec
+_fiddle_interrupt
+_fiddle_experiment
+_fiddle_the_db
 _fiddle_db_arg
 _fiddle_db_filename
-_fiddle_exec
-_fiddle_experiment
-_fiddle_interrupt
-_fiddle_main
 _fiddle_reset_db
-_fiddle_db_handle
-_fiddle_db_vfs
-_fiddle_export_db

ext/wasm/api/EXPORTED_FUNCTIONS.sqlite3-api

@@ -1,8 +1,3 @@
-_malloc
-_free
-_realloc
-_sqlite3_aggregate_context
-_sqlite3_auto_extension
 _sqlite3_bind_blob
 _sqlite3_bind_double
 _sqlite3_bind_int
@@ -10,16 +5,11 @@ _sqlite3_bind_int64
 _sqlite3_bind_null
 _sqlite3_bind_parameter_count
 _sqlite3_bind_parameter_index
-_sqlite3_bind_pointer
 _sqlite3_bind_text
-_sqlite3_busy_handler
-_sqlite3_busy_timeout
-_sqlite3_cancel_auto_extension
 _sqlite3_changes
 _sqlite3_changes64
 _sqlite3_clear_bindings
 _sqlite3_close_v2
-_sqlite3_collation_needed
 _sqlite3_column_blob
 _sqlite3_column_bytes
 _sqlite3_column_count
@@ -30,28 +20,12 @@ _sqlite3_column_int64
 _sqlite3_column_name
 _sqlite3_column_text
 _sqlite3_column_type
-_sqlite3_column_value
-_sqlite3_commit_hook
 _sqlite3_compileoption_get
 _sqlite3_compileoption_used
-_sqlite3_complete
-_sqlite3_context_db_handle
-_sqlite3_create_collation
-_sqlite3_create_collation_v2
-_sqlite3_create_function
 _sqlite3_create_function_v2
-_sqlite3_create_module
-_sqlite3_create_module_v2
-_sqlite3_create_window_function
 _sqlite3_data_count
 _sqlite3_db_filename
-_sqlite3_db_handle
 _sqlite3_db_name
-_sqlite3_db_status
-_sqlite3_declare_vtab
-_sqlite3_deserialize
-_sqlite3_drop_modules
-_sqlite3_errcode
 _sqlite3_errmsg
 _sqlite3_error_offset
 _sqlite3_errstr
@@ -59,38 +33,16 @@ _sqlite3_exec
 _sqlite3_expanded_sql
 _sqlite3_extended_errcode
 _sqlite3_extended_result_codes
-_sqlite3_file_control
 _sqlite3_finalize
-_sqlite3_free
-_sqlite3_get_auxdata
 _sqlite3_initialize
-_sqlite3_keyword_count
-_sqlite3_keyword_name
-_sqlite3_keyword_check
-_sqlite3_last_insert_rowid
+_sqlite3_interrupt
 _sqlite3_libversion
 _sqlite3_libversion_number
-_sqlite3_limit
-_sqlite3_malloc
-_sqlite3_malloc64
-_sqlite3_msize
 _sqlite3_open
 _sqlite3_open_v2
-_sqlite3_overload_function
 _sqlite3_prepare_v2
 _sqlite3_prepare_v3
-_sqlite3_preupdate_blobwrite
-_sqlite3_preupdate_count
-_sqlite3_preupdate_depth
-_sqlite3_preupdate_hook
-_sqlite3_preupdate_new
-_sqlite3_preupdate_old
-_sqlite3_progress_handler
-_sqlite3_randomness
-_sqlite3_realloc
-_sqlite3_realloc64
 _sqlite3_reset
-_sqlite3_reset_auto_extension
 _sqlite3_result_blob
 _sqlite3_result_double
 _sqlite3_result_error
@@ -98,106 +50,23 @@ _sqlite3_result_error_code
 _sqlite3_result_error_nomem
 _sqlite3_result_error_toobig
 _sqlite3_result_int
-_sqlite3_result_int64
 _sqlite3_result_null
-_sqlite3_result_pointer
-_sqlite3_result_subtype
 _sqlite3_result_text
-_sqlite3_result_zeroblob
-_sqlite3_result_zeroblob64
-_sqlite3_rollback_hook
-_sqlite3_serialize
-_sqlite3_set_authorizer
-_sqlite3_set_auxdata
-_sqlite3_set_last_insert_rowid
-_sqlite3_shutdown
 _sqlite3_sourceid
 _sqlite3_sql
-_sqlite3_status
-_sqlite3_status64
 _sqlite3_step
-_sqlite3_stmt_isexplain
-_sqlite3_stmt_readonly
-_sqlite3_stmt_status
 _sqlite3_strglob
-_sqlite3_stricmp
 _sqlite3_strlike
-_sqlite3_strnicmp
-_sqlite3_table_column_metadata
 _sqlite3_total_changes
 _sqlite3_total_changes64
-_sqlite3_trace_v2
-_sqlite3_txn_state
-_sqlite3_update_hook
-_sqlite3_uri_boolean
-_sqlite3_uri_int64
-_sqlite3_uri_key
-_sqlite3_uri_parameter
-_sqlite3_user_data
 _sqlite3_value_blob
 _sqlite3_value_bytes
 _sqlite3_value_double
-_sqlite3_value_dup
-_sqlite3_value_free
-_sqlite3_value_frombind
-_sqlite3_value_int
-_sqlite3_value_int64
-_sqlite3_value_nochange
-_sqlite3_value_numeric_type
-_sqlite3_value_pointer
-_sqlite3_value_subtype
 _sqlite3_value_text
 _sqlite3_value_type
 _sqlite3_vfs_find
 _sqlite3_vfs_register
-_sqlite3_vfs_unregister
-_sqlite3_vtab_collation
-_sqlite3_vtab_distinct
-_sqlite3_vtab_in
-_sqlite3_vtab_in_first
-_sqlite3_vtab_in_next
-_sqlite3_vtab_nochange
-_sqlite3_vtab_on_conflict
-_sqlite3_vtab_rhs_value
-_sqlite3changegroup_add
-_sqlite3changegroup_add_strm
-_sqlite3changegroup_delete
-_sqlite3changegroup_new
-_sqlite3changegroup_output
-_sqlite3changegroup_output_strm
-_sqlite3changeset_apply
-_sqlite3changeset_apply_strm
-_sqlite3changeset_apply_v2
-_sqlite3changeset_apply_v2_strm
-_sqlite3changeset_concat
-_sqlite3changeset_concat_strm
-_sqlite3changeset_conflict
-_sqlite3changeset_finalize
-_sqlite3changeset_fk_conflicts
-_sqlite3changeset_invert
-_sqlite3changeset_invert_strm
-_sqlite3changeset_new
-_sqlite3changeset_next
-_sqlite3changeset_old
-_sqlite3changeset_op
-_sqlite3changeset_pk
-_sqlite3changeset_start
-_sqlite3changeset_start_strm
-_sqlite3changeset_start_v2
-_sqlite3changeset_start_v2_strm
-_sqlite3session_attach
-_sqlite3session_changeset
-_sqlite3session_changeset_size
-_sqlite3session_changeset_strm
-_sqlite3session_config
-_sqlite3session_create
-_sqlite3session_delete
-_sqlite3session_diff
-_sqlite3session_enable
-_sqlite3session_indirect
-_sqlite3session_isempty
-_sqlite3session_memory_used
-_sqlite3session_object_config
-_sqlite3session_patchset
-_sqlite3session_patchset_strm
-_sqlite3session_table_filter
+_sqlite3_wasm_db_error
+_sqlite3_wasm_enum_json
+_malloc
+_free

ext/wasm/api/sqlite3-wasm.c

@@ -877,7 +877,7 @@ const char * sqlite3_wasm_enum_json(void){
     DefInt(SQLITE_STMTSTATUS_FILTER_HIT);
     DefInt(SQLITE_STMTSTATUS_MEMUSED);
   } _DefGroup;
-  
+
   DefGroup(syncFlags) {
     DefInt(SQLITE_SYNC_NORMAL);
     DefInt(SQLITE_SYNC_FULL);
@@ -901,6 +901,8 @@ const char * sqlite3_wasm_enum_json(void){
     DefInt(SQLITE_DETERMINISTIC);
     DefInt(SQLITE_DIRECTONLY);
     DefInt(SQLITE_INNOCUOUS);
+    DefInt(SQLITE_SUBTYPE);
+    DefInt(SQLITE_RESULT_SUBTYPE);
   } _DefGroup;
 
   DefGroup(version) {

ext/wasm/api/sqlite3-worker1-promiser.c-pp.js

@@ -114,7 +114,7 @@
    by all client code except that which tests this API. The `row`
    property contains the row result in the form implied by the
    `rowMode` option (defaulting to `'array'`). The `rowNumber` is a
-   1-based integer value incremented by 1 on each call into the
+   1-based integer value incremented by 1 on each call into th 
    callback.
 
    At the end of the result set, the same event is fired with
@@ -122,17 +122,8 @@
    the end of the result set has been reached. Note that the rows
    arrive via worker-posted messages, with all the implications
    of that.
-
-   Notable shortcomings:
-
-   - This API was not designed with ES6 modules in mind. Neither Firefox
-     nor Safari support, as of March 2023, the {type:"module"} flag to the
-     Worker constructor, so that particular usage is not something we're going
-     to target for the time being:
-
-     https://developer.mozilla.org/en-US/docs/Web/API/Worker/Worker
 */
-globalThis.sqlite3Worker1Promiser = function callee(config = callee.defaultConfig){
+self.sqlite3Worker1Promiser = function callee(config = callee.defaultConfig){
   // Inspired by: https://stackoverflow.com/a/52439530
   if(1===arguments.length && 'function'===typeof arguments[0]){
     const f = config;
@@ -169,7 +160,7 @@ globalThis.sqlite3Worker1Promiser = function callee(config = callee.defaultConfi
       if(msgHandler && msgHandler.onrow){
         msgHandler.onrow(ev);
         return;
-      }
+      }        
       if(config.onunhandled) config.onunhandled(arguments[0]);
       else err("sqlite3Worker1Promiser() unhandled worker message:",ev);
       return;
@@ -196,9 +187,10 @@ globalThis.sqlite3Worker1Promiser = function callee(config = callee.defaultConfi
     if(1===arguments.length){
       msg = arguments[0];
     }else if(2===arguments.length){
-      msg = Object.create(null);
-      msg.type = arguments[0];
-      msg.args = arguments[1];
+      msg = {
+        type: arguments[0],
+        args: arguments[1]
+      };
     }else{
       toss("Invalid arugments for sqlite3Worker1Promiser()-created factory.");
     }
@@ -244,13 +236,10 @@ globalThis.sqlite3Worker1Promiser = function callee(config = callee.defaultConfi
     return p;
   };
 }/*sqlite3Worker1Promiser()*/;
-globalThis.sqlite3Worker1Promiser.defaultConfig = {
+self.sqlite3Worker1Promiser.defaultConfig = {
   worker: function(){
 //#if target=es6-bundler-friendly
-    return new Worker("sqlite3-worker1-bundler-friendly.mjs",{
-      type: 'module' /* Noting that neither Firefox nor Safari suppor this,
-                        as of this writing. */
-    });
+    return new Worker("sqlite3-worker1.js");
 //#else
     let theJs = "sqlite3-worker1.js";
     if(this.currentScript){
@@ -258,17 +247,17 @@ globalThis.sqlite3Worker1Promiser.defaultConfig = {
       src.pop();
       theJs = src.join('/')+'/' + theJs;
       //sqlite3.config.warn("promiser currentScript, theJs =",this.currentScript,theJs);
-    }else if(globalThis.location){
-      //sqlite3.config.warn("promiser globalThis.location =",globalThis.location);
-      const urlParams = new URL(globalThis.location.href).searchParams;
+    }else{
+      //sqlite3.config.warn("promiser self.location =",self.location);
+      const urlParams = new URL(self.location.href).searchParams;
       if(urlParams.has('sqlite3.dir')){
         theJs = urlParams.get('sqlite3.dir') + '/' + theJs;
       }
     }
-    return new Worker(theJs + globalThis.location.search);
+    return new Worker(theJs + self.location.search);
 //#endif
   }.bind({
-    currentScript: globalThis?.document?.currentScript
+    currentScript: self?.document?.currentScript
   }),
   onerror: (...args)=>console.error('worker1 promiser error',...args)
 };

ext/wasm/fiddle/fiddle.html

@@ -273,6 +273,11 @@
         </fieldset>
       </div>
     </div> <!-- #view-split -->
+    <!-- Maintenance notes:
+
+        ... TODO... currently being refactored...
+
+    -->
     <script src="fiddle.js"></script>
   </body>
 </html>

main.mk

@@ -326,6 +326,7 @@ TESTSRC = \
   $(TOP)/src/test_quota.c \
   $(TOP)/src/test_rtree.c \
   $(TOP)/src/test_schema.c \
+  $(TOP)/src/test_schemapool.c \
   $(TOP)/src/test_sqllog.c \
   $(TOP)/src/test_superlock.c \
   $(TOP)/src/test_syscall.c \
@@ -384,6 +385,7 @@ TESTSRC2 = \
   $(TOP)/src/backup.c \
   $(TOP)/src/btree.c \
   $(TOP)/src/build.c \
+  $(TOP)/src/callback.c \
   $(TOP)/src/date.c \
   $(TOP)/src/dbpage.c \
   $(TOP)/src/dbstat.c \

manifest

@@ -1,13 +1,13 @@
-C Version\s3.44.0
-D 2023-11-01T11:23:50.173
+C Merge\s3.44.2\schanges\sinto\sthe\sreuse-schema-3.44\ssub-branch.
+D 2023-11-24T12:48:55.928
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
-F Makefile.in 8b59912fc1538f96a08555605c5886cdcc733696ae7f22e374b2a4752196ca20
+F Makefile.in bbd3ff2959a52fbe8c4b898ed25609fe879a21eb1f1560e2327408eac60631db
 F Makefile.linux-gcc f3842a0b1efbfbb74ac0ef60e56b301836d05b4d867d014f714fa750048f1ab6
-F Makefile.msc f0cf219350d9af4fba411b4f6306dce2adc897484e8f446de1fb4f40de674d00
+F Makefile.msc 22cfe650731e36c58e0248698724385f8880293c5dd8373d4891dd3f6bbf0c8c
 F README.md 963d30019abf0cc06b263cd2824bce022893f3f93a531758f6f04ff2194a16a8
-F VERSION 4c09b629c03b8ae32317cb336a32f3aa3252841d6dcd51184cecc4278d08f21e
+F VERSION 672a5ddf487d19856d8b1015797e14578fd8f8d59c14d9832ab0fe5938c6ab9b
 F aclocal.m4 a5c22d164aff7ed549d53a90fa56d56955281f50
 F art/sqlite370.eps aa97a671332b432a54e1d74ff5e8775be34200c2
 F art/sqlite370.ico af56c1d00fee7cd4753e8631ed60703ed0fc6e90
@@ -22,7 +22,7 @@ F autoconf/configure.ac ec7fa914c5e74ff212fe879f9bb6918e1234497e05facfb641f30c4d
 F autoconf/tea/Makefile.in 106a96f2f745d41a0f6193f1de98d7355830b65d45032c18cd7c90295ec24196
 F autoconf/tea/README 3e9a3c060f29a44344ab50aec506f4db903fb873
 F autoconf/tea/aclocal.m4 52c47aac44ce0ddb1f918b6993e8beb8eee88f43
-F autoconf/tea/configure.ac 1ee185f2f8c2e9bed69d0113222724202f962d04eafd57197e65c662d2d9b180
+F autoconf/tea/configure.ac 0c358d924fe9cd5c624b9038e025bca35b572a15501014c69afe38b8ae4d7371
 F autoconf/tea/doc/sqlite3.n e1fe45d4f5286ee3d0ccc877aca2a0def488e9bb
 F autoconf/tea/license.terms 13bd403c9610fd2b76ece0ab50c4c5eda933d523
 F autoconf/tea/pkgIndex.tcl.in b9eb6dd37f64e08e637d576b3c83259814b9cddd78bec4af2e5abfc6c5c750ce
@@ -33,7 +33,7 @@ F autoconf/tea/win/nmakehlp.c b01f822eabbe1ed2b64e70882d97d48402b42d2689a1ea0034
 F autoconf/tea/win/rules.vc c511f222b80064096b705dbeb97060ee1d6b6d63
 F config.guess 883205ddf25b46f10c181818bf42c09da9888884af96f79e1719264345053bd6
 F config.sub c2d0260f17f3e4bc0b6808fccf1b291cb5e9126c14fc5890efc77b9fd0175559
-F configure 1d9cbcb416cb5387b3f750ae6db63cfedb703a2e46bf8ca61daecff31d208252 x
+F configure a56c8f24e118eff90e3870411bfc844e86c00577faf092ded131120a637ad2da x
 F configure.ac de31fea7d975bb7ebafbe0e2190a855cc80d48558bf0c9a6578a1836daf1cd3a
 F contrib/sqlitecon.tcl 210a913ad63f9f991070821e599d600bd913e0ad
 F doc/F2FS.txt c1d4a0ae9711cfe0e1d8b019d154f1c29e0d3abfe820787ba1e9ed7691160fcd
@@ -41,6 +41,7 @@ F doc/compile-for-windows.md 922ba580d210a1f1bd3ef9d0413121556f9b5714fb5c01e664d
 F doc/json-enhancements.md e356fc834781f1f1aa22ee300027a270b2c960122468499bf347bb123ce1ea4f
 F doc/lemon.html 44a53a1d2b42d7751f7b2f478efb23c978e258d794bfd172442307a755b9fa44
 F doc/pager-invariants.txt 27fed9a70ddad2088750c4a2b493b63853da2710
+F doc/shared_schema.md 759fc374709fccf4e5d2d0cbd05f8fedd38fb022bdd8a6c5b5f492684c7023b9
 F doc/testrunner.md 2434864be2219d4f0b6ffc99d0a2172d531c4ca4345340776f67ad4edd90dc90
 F doc/trusted-schema.md 33625008620e879c7bcfbbfa079587612c434fa094d338b08242288d358c3e8a
 F doc/vdbesort-memory.md 4da2639c14cd24a31e0af694b1a8dd37eaf277aff3867e9a8cc14046bc49df56
@@ -50,6 +51,8 @@ F ext/README.md fd5f78013b0a2bc6f0067afb19e6ad040e89a10179b4f6f03eee58fac5f169bd
 F ext/async/README.txt e12275968f6fde133a80e04387d0e839b0c51f91
 F ext/async/sqlite3async.c 6f247666b495c477628dd19364d279c78ea48cd90c72d9f9b98ad1aff3294f94
 F ext/async/sqlite3async.h 46b47c79357b97ad85d20d2795942c0020dc20c532114a49808287f04aa5309a
+F ext/consio/console_io.c e048bd69f3a357a4b6b5da01c504728631d944ad5735ad83c44800c80a91e978 x
+F ext/consio/console_io.h d18bcc50f4e4d42b65be8fecba72918364ae77182c86360aca842e44b823384e
 F ext/expert/README.md b321c2762bb93c18ea102d5a5f7753a4b8bac646cb392b3b437f633caf2020c3
 F ext/expert/expert.c d548d603a4cc9e61f446cc179c120c6713511c413f82a4a32b1e1e69d3f086a4
 F ext/expert/expert1.test 0dd5cb096d66bed593e33053a3b364f6ef52ed72064bf5cf298364636dbf3cd6
@@ -93,8 +96,8 @@ F ext/fts5/fts5_aux.c 35c4101613eff86902877a4dedd9400b07922e412cbdd637b45041dce2
 F ext/fts5/fts5_buffer.c 3001fbabb585d6de52947b44b455235072b741038391f830d6b729225eeaf6a5
 F ext/fts5/fts5_config.c 054359543566cbff1ba65a188330660a5457299513ac71c53b3a07d934c7b081
 F ext/fts5/fts5_expr.c bd3b81ce669c4104e34ffe66570af1999a317b142c15fccb112de9fb0caa57a6
-F ext/fts5/fts5_hash.c 65e7707bc8774706574346d18c20218facf87de3599b995963c3e6d6809f203d
-F ext/fts5/fts5_index.c 730c9c32ada18ce1eb7ff847b36507f4b005d88d47af7b47db521e695a8ea4c7
+F ext/fts5/fts5_hash.c 076058f93327051952a752dc765df1acfe783eb11b419b30652aa1fc1f987902
+F ext/fts5/fts5_index.c 458cbed8a3e17617cbf7e80cdfb7612000b9bb3781f286b345fb9655858658cf
 F ext/fts5/fts5_main.c a07ed863b8bd9e6fefb62db2fd40a3518eb30a5f7dcfda5be915dd2db45efa2f
 F ext/fts5/fts5_storage.c 5d10b9bdcce5b90656cad13c7d12ad4148677d4b9e3fca0481fca56d6601426d
 F ext/fts5/fts5_tcl.c b1445cbe69908c411df8084a10b2485500ac70a9c747cdc8cda175a3da59d8ae
@@ -143,7 +146,7 @@ F ext/fts5/test/fts5corrupt.test b6d4034b682bb3387bc44c510c71b3c67d4349e4df13949
 F ext/fts5/test/fts5corrupt2.test 99e7e23a58b4d89eb7167c6de1669cbc595cd3c79ab333e0eb56405473319e77
 F ext/fts5/test/fts5corrupt3.test 7da9895dafa404efd20728f66ff4b94399788bdc042c36fe2689801bba2ccd78
 F ext/fts5/test/fts5corrupt4.test f4c08e2182a48d8b70975fd869ee5391855c06d8a0ff87b6a2529e7c5a88a1d3
-F ext/fts5/test/fts5corrupt5.test eb6ba5ca28ef7c4c6b01e850d388cdb3dacc8c4c2f383f79d0a98128257742b4
+F ext/fts5/test/fts5corrupt5.test 38a238df26c4de471e1c4b98f8de6c902bc692577a1c08d0ff4f2251f3559644
 F ext/fts5/test/fts5corrupt6.test bf8eeae07825b088b9665d9d8e4accbd8dc9bf3cb85b6c64cf6c9e18ccc420a4
 F ext/fts5/test/fts5corrupt7.test 80ad7f683a8bda2404731bb77e8c3dbbb620c1f6cc583cca8239f6accd6338c0
 F ext/fts5/test/fts5delete.test 619295b20dbc1d840b403ee07c878f52378849c3c02e44f2ee143b3e978a0aa7
@@ -167,7 +170,7 @@ F ext/fts5/test/fts5faultB.test d606bdb8e81aaeb6f41de3fc9fc7ae315733f0903fbff05c
 F ext/fts5/test/fts5faultD.test e7ed7895abfe6bc98a5e853826f6b74956e7ba7f594f1860bbf9e504b9647996
 F ext/fts5/test/fts5faultE.test 844586ce71dab4be85bb86880e87b624d089f851654cd22e4710c77eb8ce7075
 F ext/fts5/test/fts5faultF.test 4abef99f86e99d9f0c6460dd68c586a766b6b9f1f660ada55bf2e8266bd1bbc1
-F ext/fts5/test/fts5faultG.test 340e59d2c2c1c7c379224f3968ee8d09b0f64bf56c5194217d1ded887b9d47c4
+F ext/fts5/test/fts5faultG.test d2e5a4d9a34e08dcaadcaeafef74d10cbc2abdd11aa2659a18af0294bf2812d3
 F ext/fts5/test/fts5first.test 3fcf2365c00a15fc9704233674789a3b95131d12de18a9b996159f6909dc8079
 F ext/fts5/test/fts5full.test e1701a112354e0ff9a1fdffb0c940c576530c33732ee20ac5e8361777070d717
 F ext/fts5/test/fts5fuzz1.test 238d8c45f3b81342aa384de3e581ff2fa330bf922a7b69e484bbc06051a1080e
@@ -193,7 +196,7 @@ F ext/fts5/test/fts5plan.test b65cfcca9ddd6fdaa118c61e17aeec8e8433bc5b6bb307abd1
 F ext/fts5/test/fts5porter.test 8d08010c28527db66bc3feebd2b8767504aaeb9b101a986342fa7833d49d0d15
 F ext/fts5/test/fts5porter2.test 0d251a673f02fa13ca7f011654873b3add20745f7402f108600a23e52d8c7457
 F ext/fts5/test/fts5prefix.test a0fa67b06650f2deaa7bf27745899d94e0fb547ad9ecbd08bfad98c04912c056
-F ext/fts5/test/fts5prefix2.test 3847ce46f70b82d61c6095103a9d7c53f2952c40a4704157bc079c04d9c8b18b
+F ext/fts5/test/fts5prefix2.test ad751d4a5b029726ee908a7664e27d27bde7584218b8d7944c2a323afd381432
 F ext/fts5/test/fts5query.test ac363b17a442620bb0780e93c24f16a5f963dfe2f23dc85647b869efcfada728
 F ext/fts5/test/fts5rank.test 30f29e278cd7fb8831ba4f082feb74d8eb90c463bf07113ae200afc2b467ef32
 F ext/fts5/test/fts5rebuild.test 55d6f17715cddbf825680dd6551efbc72ed916d8cf1cde40a46fc5d785b451e7
@@ -207,6 +210,7 @@ F ext/fts5/test/fts5secure4.test 0d10a80590c07891478700af7793b232962042677432b98
 F ext/fts5/test/fts5secure5.test c07a68ced5951567ac116c22f2d2aafae497e47fe9fcb6a335c22f9c7a4f2c3a
 F ext/fts5/test/fts5secure6.test 74bf04733cc523bccca519bb03d3b4e2ed6f6e3db7c59bf6be82c88a0ac857fd
 F ext/fts5/test/fts5secure7.test fd03d0868d64340a1db8615b02e5508fea409de13910114e4f19eaefc120777a
+F ext/fts5/test/fts5secure8.test eb3579e9d58b0acad97e8082dee1f99b2d393198f03500b453c2b25761c0c298
 F ext/fts5/test/fts5securefault.test dbca2b6a1c16700017f5051138991b705410889933f2a37c57ae8a23b296b10b
 F ext/fts5/test/fts5simple.test a298670508c1458b88ce6030440f26a30673931884eb5f4094ac1773b3ba217b
 F ext/fts5/test/fts5simple2.test 258a1b0c590409bfa5271e872c79572b319d2a56554d0585f68f146a0da603f0
@@ -560,7 +564,7 @@ F ext/session/test_session.c 7b94ad945cd4afe6c73ee935aeb3d44b4446186e1729362af61
 F ext/userauth/sqlite3userauth.h 7f3ea8c4686db8e40b0a0e7a8e0b00fac13aa7a3
 F ext/userauth/user-auth.txt e6641021a9210364665fe625d067617d03f27b04
 F ext/userauth/userauth.c 7f00cded7dcaa5d47f54539b290a43d2e59f4b1eb5f447545fa865f002fc80cb
-F ext/wasm/EXPORTED_FUNCTIONS.fiddle.in 27450c8b8c70875a260aca55435ec927068b34cef801a96205adb81bdcefc65c
+F ext/wasm/EXPORTED_FUNCTIONS.fiddle 7fb73f7150ab79d83bb45a67d257553c905c78cd3d693101699243f36c5ae6c3
 F ext/wasm/GNUmakefile 0e362f3fc04eab6628cbe4f1e35f4ab4a200881f6b5f753b27fb45eabeddd9d2
 F ext/wasm/README-dist.txt 6382cb9548076fca472fb3330bbdba3a55c1ea0b180ff9253f084f07ff383576
 F ext/wasm/README.md a8a2962c3aebdf8d2104a9102e336c5554e78fc6072746e5daf9c61514e7d193
@@ -569,7 +573,7 @@ F ext/wasm/SQLTester/SQLTester.mjs ec2f6ba63a0f2f0562941a0fb8e46b7dc55589711513f
 F ext/wasm/SQLTester/SQLTester.run.mjs c72b7fe2072d05992f7a3d8c6a1d34e95712513ceabe40849784e24e41c84638
 F ext/wasm/SQLTester/index.html 3f8a016df0776be76605abf20e815ecaafbe055abac0e1fe5ea080e7846b760d
 F ext/wasm/SQLTester/touint8array.c 2d5ece04ec1393a6a60c4bf96385bda5e1a10ad49f3038b96460fc5e5aa7e536
-F ext/wasm/api/EXPORTED_FUNCTIONS.sqlite3-api d6a5078f48a5301ed17b9a30331075d9b2506e1360c1f0dee0c7816c10acd9ab
+F ext/wasm/api/EXPORTED_FUNCTIONS.sqlite3-api c5eaceabb9e759aaae7d3101a4a3e542f96ab2c99d89a80ce20ec18c23115f33
 F ext/wasm/api/EXPORTED_FUNCTIONS.sqlite3-see fb29e62082a658f0d81102488414d422c393c4b20cc2f685b216bc566237957b
 F ext/wasm/api/EXPORTED_RUNTIME_METHODS.sqlite3-api 1ec3c73e7d66e95529c3c64ac3de2470b0e9e7fbf7a5b41261c367cf4f1b7287
 F ext/wasm/api/README.md 5eb44fa02e9c693a1884a3692428647894b0380b24bca120866b7a24c8786134
@@ -588,8 +592,8 @@ F ext/wasm/api/sqlite3-opfs-async-proxy.js 8cf8a897726f14071fae6be6648125162b256
 F ext/wasm/api/sqlite3-v-helper.js 7daa0eab0a513a25b05e9abae7b5beaaa39209b3ed12f86aeae9ef8d2719ed25
 F ext/wasm/api/sqlite3-vfs-opfs-sahpool.c-pp.js 595953994aa3ae2287c889c4da39ab3d6f17b6461ecf4bec334b7a3faafddb02
 F ext/wasm/api/sqlite3-vfs-opfs.c-pp.js 46c4afa6c50d7369252c104f274ad977a97e91ccfafc38b400fe36e90bdda88e
-F ext/wasm/api/sqlite3-wasm.c 038de1b6d40b2cc0f41a143a0451db60b2a6f1b5bc06de67da255c54ea1661b7
-F ext/wasm/api/sqlite3-worker1-promiser.c-pp.js bc06df0d599e625bde6a10a394e326dc68da9ff07fa5404354580f81566e591f
+F ext/wasm/api/sqlite3-wasm.c d0e09eb5ed3743c00294e30019e591c3aa150572ae7ffe8a8994568a7377589f
+F ext/wasm/api/sqlite3-worker1-promiser.c-pp.js c5ac33e39f21a3481812d7333ca6e18853640d423a01960ca8dbc6e7c5c3c21c
 F ext/wasm/api/sqlite3-worker1.c-pp.js a541112aa51e16705f13a99bb943c64efe178aa28c86704a955f8fd9afe4ba37
 F ext/wasm/batch-runner.html 4deeed44fe41496dc6898d9fb17938ea3291f40f4bfb977e29d0cef96fbbe4c8
 F ext/wasm/batch-runner.js 0dad6a02ad796f1003d3b7048947d275c4d6277f63767b8e685c27df8fdac93e
@@ -612,8 +616,8 @@ F ext/wasm/example_extra_init.c 2347cd69d19d839ef4e5e77b7855103a7fe3ef2af86f2e8c
 F ext/wasm/fiddle.make fa2ba6e90457ba2a71cb745f200d409caf773076df75ae5b177cc225d7627a11
 F ext/wasm/fiddle/emscripten.css 3d253a6fdb8983a2ac983855bfbdd4b6fa1ff267c28d69513dd6ef1f289ada3f
 F ext/wasm/fiddle/fiddle-worker.js e0153f9af6500805c6f09c0b3cfdb7d857e9d6863dbee9d50d1628fccf5f4b4d
+F ext/wasm/fiddle/fiddle.html 550c5aafce40bd218de9bf26192749f69f9b10bc379423ecd2e162bcef885c08
 F ext/wasm/fiddle/fiddle.js 974b995119ac443685d7d94d3b3c58c6a36540e9eb3fed7069d5653284071715
-F ext/wasm/fiddle/index.html 5daf54e8f3d7777cbb1ca4f93affe28858dbfff25841cb4ab81d694efed28ec2
 F ext/wasm/index-dist.html 22379774f0ad4edcaaa8cf9c674c82e794cc557719a8addabed74eb8069d412e
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 F ext/wasm/jaccwabyt/jaccwabyt.js 1264710db3cfbcb6887d95665b7aeba60c1126eaef789ca4cf1a4a17d5bc7f54
@@ -641,7 +645,7 @@ F ext/wasm/wasmfs.make 8a4955882aaa0783b3f60a9484a1f0f3d8b6f775c0fcd17c082f31966
 F install-sh 9d4de14ab9fb0facae2f48780b874848cbf2f895 x
 F ltmain.sh 3ff0879076df340d2e23ae905484d8c15d5fdea8
 F magic.txt 5ade0bc977aa135e79e3faaea894d5671b26107cc91e70783aa7dc83f22f3ba0
-F main.mk 51fd5fc8565007266e6bfd9e299199c752b171707a667b8914a204b38258e1b1
+F main.mk 50fd9cf8e3dbbfb13b96b1bbb46573958ab61eef20edcc7146c9a089aa2a0983
 F mptest/config01.test 3c6adcbc50b991866855f1977ff172eb6d901271
 F mptest/config02.test 4415dfe36c48785f751e16e32c20b077c28ae504
 F mptest/crash01.test 61e61469e257df0850df4293d7d4d6c2af301421
@@ -653,9 +657,9 @@ F sqlite.pc.in 42b7bf0d02e08b9e77734a47798d1a55a9e0716b
 F sqlite3.1 acdff36db796e2d00225b911d3047d580cd136547298435426ce9d40347973cc
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 F sqlite_cfg.h.in baf2e409c63d4e7a765e17769b6ff17c5a82bbd9cbf1e284fd2e4cefaff3fcf2
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-F src/analyze.c d4cc28738c29e009640ec20ebb6936ba6fcefff0d11aa93398d9bb9a5ead6c1f
-F src/attach.c cc9d00d30da916ff656038211410ccf04ed784b7564639b9b61d1839ed69fd39
+F src/alter.c 47253323822cc2ad54d5fe5695db683fae2f904242e9df55a1bc5406b1293e3a
+F src/analyze.c caf60d36dd2be963a2a85bac3c0555ae97a8b295dd66c1e95ac868b69400c92b
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 F src/auth.c 19b7ccacae3dfba23fc6f1d0af68134fa216e9040e53b0681b4715445ea030b4
 F src/backup.c 5c97e8023aab1ce14a42387eb3ae00ba5a0644569e3476f38661fa6f824c3523
 F src/bitvec.c 9eac5f42c11914d5ef00a75605bb205e934f435c579687f985f1f8b0995c8645
@@ -663,15 +667,15 @@ F src/btmutex.c 79a43670447eacc651519a429f6ece9fd638563cf95b469d6891185ddae2b522
 F src/btree.c f3b09c5414de3a11db73e11e1d66f4c5e53c9e89876ff3b531a887ab656ca303 x
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 F src/btreeInt.h ef12a72b708677e48d6bc8dcd66fed25434740568b89e2cfa368093cfc5b9d15
-F src/build.c 189e4517d67f09f0a3e0d8e1faa6e2ef0c2e95f6ac82e33c912cb7efa2a359cc
-F src/callback.c db3a45e376deff6a16c0058163fe0ae2b73a2945f3f408ca32cf74960b28d490
+F src/build.c 154393fc1ba71c974baffeeda4eeec4116890d553d5efe6a8847363ae8116193
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 F src/complete.c a3634ab1e687055cd002e11b8f43eb75c17da23e
 F src/ctime.c 23331529e654be40ca97d171cbbffe9b3d4c71cc53b78fe5501230675952da8b
 F src/date.c eebc54a00e888d3c56147779e9f361b77d62fd69ff2008c5373946aa1ba1d574
 F src/dbpage.c 80e46e1df623ec40486da7a5086cb723b0275a6e2a7b01d9f9b5da0f04ba2782
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 F src/delete.c cb766727c78e715f9fb7ec8a7d03658ed2a3016343ca687acfcec9083cdca500
-F src/expr.c 433f12e1237524482b0b2681c07da3cd54ddada2a625237cecde419f3e3a2553
+F src/expr.c cacf230b124891ea830d80395ea2119c2d7ee52c134a010f3950de9391ab79d1
 F src/fault.c 460f3e55994363812d9d60844b2a6de88826e007
 F src/fkey.c a47610f0a5c6cb0ad79f8fcef039c01833dec0c751bb695f28dc0ec6a4c3ba00
 F src/func.c 472f6dcfa39cf54f89a6aec76c79c225fb880a6c14469c15d361331662b9bf43
@@ -681,10 +685,10 @@ F src/hash.h 3340ab6e1d13e725571d7cee6d3e3135f0779a7d8e76a9ce0a85971fa3953c51
 F src/hwtime.h f9c2dfb84dce7acf95ce6d289e46f5f9d3d1afd328e53da8f8e9008e3b3caae6
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 F src/insert.c 3f0a94082d978bbdd33c38fefea15346c6c6bffb70bc645a71dc0f1f87dd3276
-F src/json.c d69c6e28ff7b602877bda68cd20583b8487c059759aa4d154dd21b3fd99c6238
+F src/json.c b2045aafc52f0475dc5d723d11cc0aaa9e1d233a28031b08c8174a3e407ed50c
 F src/legacy.c d7874bc885906868cd51e6c2156698f2754f02d9eee1bae2d687323c3ca8e5aa
 F src/loadext.c 7432c944ff197046d67a1207790a1b13eec4548c85a9457eb0896bb3641dfb36
-F src/main.c e1bc8864834697503d370d94613be945d05ca1c5ebdda43e7d5c8ee8c48d433c
+F src/main.c 54f4f37cc1c38cceab89f3aa0b372cfc8c2be1756e2c6de8760a63f656af9d7c
 F src/malloc.c f016922435dc7d1f1f5083a03338a3e91f8c67ce2c5bdcfa4cdef62e612f5fcc
 F src/mem0.c 6a55ebe57c46ca1a7d98da93aaa07f99f1059645
 F src/mem1.c 3bb59158c38e05f6270e761a9f435bf19827a264c13d1631c58b84bdc96d73b2
@@ -698,7 +702,7 @@ F src/mutex.c 1b4c7e5e3621b510e0c18397210be27cd54c8084141144fbbafd003fde948e88
 F src/mutex.h a7b2293c48db5f27007c3bdb21d438873637d12658f5a0bf8ad025bb96803c4a
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 F src/mutex_unix.c f7ee5a2061a4c11815a2bf4fc0e2bfa6fb8d9dc89390eb613ca0cec32fc9a3d1
-F src/mutex_w32.c 38b56d0bc8d54c17c20cbaaad3719b0c36b92fd07a7e34360d0c6a18d5589912
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 F src/notify.c 57c2d1a2805d6dee32acd5d250d928ab94e02d76369ae057dee7d445fd64e878
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 F src/os.h 1ff5ae51d339d0e30d8a9d814f4b8f8e448169304d83a7ed9db66a65732f3e63
@@ -708,29 +712,29 @@ F src/os_setup.h 6011ad7af5db4e05155f385eb3a9b4470688de6f65d6166b8956e58a3d87210
 F src/os_unix.c cb116fde9e3ca3c1bbfdf89d6928f776a2a34da168e2667426523a4db353b271
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 F src/os_win.h 7b073010f1451abe501be30d12f6bc599824944a
-F src/pager.c 699aab8dfc88056d796b03b40c0ab979040d58dfc3ae9db207f1be91e4880bbf
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 F src/sqliteLimit.h 33b1c9baba578d34efe7dfdb43193b366111cdf41476b1e82699e14c11ee1fb6
-F src/status.c 160c445d7d28c984a0eae38c144f6419311ed3eace59b44ac6dafc20db4af749
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 F src/table.c 0f141b58a16de7e2fbe81c308379e7279f4c6b50eb08efeec5892794a0ba30d1
-F src/tclsqlite.c ecbc3c99c0d0c3ed122a913f143026c26d38d57f33e06bb71185dd5c1efe37cd
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 F src/test3.c e5178558c41ff53236ae0271e9acb3d6885a94981d2eb939536ee6474598840e
@@ -745,7 +749,7 @@ F src/test_backup.c bf5da90c9926df0a4b941f2d92825a01bbe090a0
 F src/test_bestindex.c f6af1e41cb7901edafb065a8198e4a0192dd42432b642d038965be5e628dec12
 F src/test_blob.c ae4a0620b478548afb67963095a7417cd06a4ec0a56adb453542203bfdcb31ce
 F src/test_btree.c 8b2dc8b8848cf3a4db93f11578f075e82252a274
-F src/test_config.c f0cc1f517deaa96dd384822ae2bb91534fa56aa458528b439830d709941d3932
+F src/test_config.c f8353821fbdc038bd080b5b125be365001ed3d9027d6410d0e40b4842e721778
 F src/test_delete.c e2fe07646dff6300b48d49b2fee2fe192ed389e834dd635e3b3bac0ce0bf9f8f
 F src/test_demovfs.c 38a459d1c78fd9afa770445b224c485e079018d6ac07332ff9bd07b54d2b8ce9
 F src/test_devsym.c 649434ed34d0b03fbd5a6b42df80f0f9a7e53f94dd1710aad5dd8831e91c4e86
@@ -769,10 +773,11 @@ F src/test_quota.c ea44c05f29b995bdb71c55eb0c602604884e55681d59b7736e604bbcc68b0
 F src/test_quota.h 2a8ad1952d1d2ca9af0ce0465e56e6c023b5e15d
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 F src/test_schema.c cbfd7a9a9b6b40d4377d0c76a6c5b2a58387385977f26edab4e77eb5f90a14ce
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 F src/test_sqllog.c 540feaea7280cd5f926168aee9deb1065ae136d0bbbe7361e2ef3541783e187a
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 F src/test_syscall.c 9fdb13b1df05e639808d44fcb8f6064aaded32b6565c00b215cfd05a060d1aca
-F src/test_tclsh.c 3ff5d188a72f00807425954ea3b493dfd3a4b890ecc6700ea83bad2fd1332ecf
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 F src/test_tclvar.c 3273f9d59395b336e381b53cfc68ec6ebdaada4e93106a2e976ffb0550504e1c
 F src/test_thread.c 7ddcf0c8b79fa3c1d172f82f322302c963d923cdb503c6171f3c8081586d0b01
 F src/test_vdbecov.c f60c6f135ec42c0de013a1d5136777aa328a776d33277f92abac648930453d43
@@ -785,32 +790,32 @@ F src/test_wsd.c 41cadfd9d97fe8e3e4e44f61a4a8ccd6f7ca8fe9
 F src/threads.c 4ae07fa022a3dc7c5beb373cf744a85d3c5c6c3c
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 F src/treeview.c 62fafcd31eea60b718f8daf448116b7b19f90134ebc6c20777ddbb07f56a3d28
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 F src/upsert.c fa125a8d3410ce9a97b02cb50f7ae68a2476c405c76aa692d3acf6b8586e9242
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 F src/vdbeInt.h 949669dfd8a41550d27dcb905b494f2ccde9a2e6c1b0b04daa1227e2e74c2b2c
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-F src/vdbemem.c c936e9002af4993b84c4eb7133d6b1190efe46d391cc86117ecd67ba17b1a04b
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 F test/8_3_names.test ebbb5cd36741350040fd28b432ceadf495be25b2
 F test/affinity2.test ce1aafc86e110685b324e9a763eab4f2a73f737842ec3b687bd965867de90627
 F test/affinity3.test f094773025eddf31135c7ad4cde722b7696f8eb07b97511f98585addf2a510a9
@@ -820,7 +825,7 @@ F test/aggnested.test 2e738bfe2980df301a782f6e7bbf9459266f64f7e72f58f3b5c843bf89
 F test/aggorderby.test e6b98dbbf3ababa96892435d387de2dcf602ef02c2b848d2d817473066f154ba
 F test/alias.test 4529fbc152f190268a15f9384a5651bbbabc9d87
 F test/all.test 2ecb8bbd52416642e41c9081182a8df05d42c75637afd4488aace78cc4b69e13
-F test/alter.test 403a7f8842457044a994d0ffb42963d6e84fcfbf5e8f54556063b25d966cd454
+F test/alter.test 3c00eff1e2036b9f93e9cd0f3d3e63750ac87ecb5bc71b9d7bd07cbf2ac4c494
 F test/alter2.test a966ccfcddf9ce0a4e0e6ff1aca9e6e7948e0e242cd7e43fc091948521807687
 F test/alter3.test ffc4ab29ce78a3517a66afd69b2730667e3471622509c283b2bd4c46f680fba3
 F test/alter4.test 716caa071dd8a3c6d57225778d15d3c3cbf5e34b2e84ae44199aeb2bbf50a707
@@ -1266,7 +1271,7 @@ F test/index8.test caa097735c91dbc23d8a402f5e63a2a03c83840ba3928733ed7f9a03f8a91
 F test/index9.test 2ac891806a4136ef3e91280477e23114e67575207dc331e6797fa0ed9379f997
 F test/indexA.test 11d84f6995e6e5b9d8315953fb1b6d29772ee7c7803ee9112715e7e4dd3e4974
 F test/indexedby.test f21eca4f7a6ffe14c8500a7ad6cd53166666c99e5ccd311842a28bc94a195fe0
-F test/indexexpr1.test 62558b1cfd7ccbe7bc015849cc6d1a13ef124e80cbd5b3a98dc66c3c9cce0cf4
+F test/indexexpr1.test 833f511213a5e26549186813f0566bd72f978177a7e6e98a2d2dd695de3c670d
 F test/indexexpr2.test 1c382e81ef996d8ae8b834a74f2a9013dddf59214c32201d7c8a656d739f999a
 F test/indexfault.test 98d78a8ff1f5335628b62f886a1cb7c7dac1ef6d48fa39c51ec871c87dce9811
 F test/init.test 15c823093fdabbf7b531fe22cf037134d09587a7
@@ -1306,7 +1311,7 @@ F test/joinC.test 1f1a602c2127f55f136e2cbd3bf2d26546614bf8cffe5902ec1ac9c07f87f2
 F test/joinD.test 2ce62e7353a0702ca5e70008faf319c1d4686aa19fba34275c6d1da0e960be28
 F test/joinE.test d5d182f3812771e2c0d97c9dcf5dbe4c41c8e21c82560e59358731c4a3981d6b
 F test/joinF.test 53dd66158806823ea680dd7543b5406af151b5aafa5cd06a7f3231cd94938127
-F test/joinH.test 84198ea42bf78b79fe399c0567218cd6df36c50c6dd27d9c4aab221acaad929e
+F test/joinH.test f69e5b53b7d887914e854b6a131efbed4ea9f5ca52bdab81788bfc3e79299f43
 F test/journal1.test c7b768041b7f494471531e17abc2f4f5ebf9e5096984f43ed17c4eb80ba34497
 F test/journal2.test 9dac6b4ba0ca79c3b21446bbae993a462c2397c4
 F test/journal3.test 7c3cf23ffc77db06601c1fcfc9743de8441cb77db9d1aa931863d94f5ffa140e
@@ -1322,7 +1327,7 @@ F test/json102.test 4c69694773a470f1fda34e5f4ba24920b35184fb66050b450fc2ef9ab5ad
 F test/json103.test 53df87f83a4e5fa0c0a56eb29ff6c94055c6eb919f33316d62161a8880112dbe
 F test/json104.test 1b844a70cddcfa2e4cd81a5db0657b2e61e7f00868310f24f56a9ba0114348c1
 F test/json105.test 11670a4387f4308ae0318cadcbd6a918ea7edcd19fbafde020720a073952675d
-F test/json501.test f71710f60fa45b19dc336fbaac9e8362f70f80cf81badefdb845ed3f7c7c2ccc
+F test/json501.test c419deb835b70c1a2c8532936927bcc1146730328edd2052276715bfd209724d
 F test/json502.test 98c38e3c4573841028a1381dfb81d4c3f9b105d39668167da10d055e503f6d0b
 F test/keyword1.test 37ef6bba5d2ed5b07ecdd6810571de2956599dff
 F test/kvtest.c 6e0228409ea7ca0497dad503fbd109badb5e59545d131014b6aaac68b56f484a
@@ -1489,6 +1494,13 @@ F test/resetdb.test 54c06f18bc832ac6d6319e5ab23d5c8dd49fdbeec7c696d791682a8006bd
 F test/resolver01.test f4022acafda7f4d40eca94dbf16bc5fc4ac30ceb
 F test/returning1.test db532cde29d6aebbc48c6ddc3149b30476f8e69ca7a2c4b53986c7635e6fd8ec
 F test/returningfault.test ae4c4b5e8745813287a359d9ccdb9d5c883c2e68afb18fb0767937d5de5692a4
+F test/reuse1.test faa2ce5ff566d936b8a10d9e22ba2ee66a54ce89fdcf8aef561df6b15b0ff3d3
+F test/reuse2.test 025d54dcbf5bb32a869ffde4884789af2ec4a302b7dc4550dfbd16e635a3dd65
+F test/reuse3.test fa1edd6a303bbb93aa076d6579fce9d2ee2d9e1a8f4d7b613ac20a76ba622eaa
+F test/reuse4.test adaad66253aea6cc748674328abe69b650c5c78b8676ed1162d3de09742519f9
+F test/reuse5.test bbe6cf7384ef90f134392edd93d626385ef0bf6f40eefc3d993535cd0861d83b
+F test/reuse6.test f4674f9967aee2a0b49c02832120b8b495291c0d87aae084c54e6c0cc18132fe
+F test/reusefault.test ef646a0fb51d50ddfb4b7cd872f88e7d36eaba64bde7797b3418c3774e1c8d14
 F test/rollback.test 06680159bc6746d0f26276e339e3ae2f951c64812468308838e0a3362d911eaa
 F test/rollback2.test 3f3a4e20401825017df7e7671e9f31b6de5fae5620c2b9b49917f52f8c160a8f
 F test/rollbackfault.test 0e646aeab8840c399cfbfa43daab46fd609cf04a
@@ -1561,7 +1573,7 @@ F test/sharedA.test 64bdd21216dda2c6a3bd3475348ccdc108160f34682c97f2f51c19fc0e21
 F test/sharedB.test 1a84863d7a2204e0d42f2e1606577c5e92e4473fa37ea0f5bdf829e4bf8ee707
 F test/shared_err.test 32634e404a3317eeb94abc7a099c556a346fdb8fb3858dbe222a4cbb8926a939
 F test/sharedlock.test 5ede3c37439067c43b0198f580fd374ebf15d304
-F test/shell1.test 2191c892d8256b1b6cccb4fca894cfc2e748450cf422e6ec80a320a0d538b6df
+F test/shell1.test c7127a5e780ffc9e14c476773127fdf292c6db226529c44c1676f37b3793123f
 F test/shell2.test 35226c070a8c7f64fd016dfac2a0db2a40f709b3131f61daacd9dad61536c9cb
 F test/shell3.test 91febeac0412812bf6370abb8ed72700e32bf8f9878849414518f662dfd55e8a
 F test/shell4.test 9abd0c12a7e20a4c49e84d5be208d2124fa6c09e728f56f1f4bee0f02853935f
@@ -1638,7 +1650,7 @@ F test/tabfunc01.test 54f27eacd054aa528a8b6e3331192c484104f30aaee351ad035f2b39a0
 F test/table.test 7862a00b58b5541511a26757ea9c5c7c3f8298766e98aa099deec703d9c0a8e0
 F test/tableapi.test ecbcc29c4ab62c1912c3717c48ea5c5e59f7d64e4a91034e6148bd2b82f177f4
 F test/tableopts.test dba698ba97251017b7c80d738c198d39ab747930
-F test/tclsqlite.test ad0bbd92edabe64cc91d990a0748142fe5ab962d74ac71fa3bfa94d50d2f4c87
+F test/tclsqlite.test 350536a4233914aa437b6735e3e8e683e921a71ced8fa9fb5396057a04dbea33
 F test/tempdb.test 4cdaa23ddd8acb4d79cbb1b68ccdfd09b0537aaba909ca69a876157c2a2cbd08
 F test/tempdb2.test 353864e96fd3ae2f70773d0ffbf8b1fe48589b02c2ec05013b540879410c3440
 F test/tempfault.test 0c0d349c9a99bf5f374655742577f8712c647900
@@ -1646,7 +1658,7 @@ F test/temptable.test d2c9b87a54147161bcd1822e30c1d1cd891e5b30
 F test/temptable2.test 76821347810ecc88203e6ef0dd6897b6036ac788e9dd3e6b04fd4d1631311a16
 F test/temptable3.test d11a0974e52b347e45ee54ef1923c91ed91e4637
 F test/temptrigger.test 38f0ca479b1822d3117069e014daabcaacefffcc
-F test/tester.tcl 68454ef88508c196d19e8694daa27bff7107a91857799eaa12f417188ae53ede
+F test/tester.tcl 9454edbf4df07b8294d15fb9695e8c7dc0b91eb979c3e888e205e7f3cdaf373f
 F test/testrunner.tcl 14c8b8ece841b1dd17516a0dc9c7ad9b5f4d4db7987974d3fdf66ae56b2a71fa
 F test/testrunner_data.tcl 7f73f93634d32dafc857ed491b840f371113d09fde6a8bfb9e47b938d47b8c85
 F test/thread001.test a0985c117eab62c0c65526e9fa5d1360dd1cac5b03bde223902763274ce21899
@@ -1660,7 +1672,7 @@ F test/thread3.test a12656a56cdf67acb6a2ff7638826c6d6a645f79909d86df521045ad31cf
 F test/thread_common.tcl 334639cadcb9f912bf82aa73f49efd5282e6cadd
 F test/threadtest1.c 6029d9c5567db28e6dc908a0c63099c3ba6c383b
 F test/threadtest2.c a70a8e94bef23339d34226eb9521015ef99f4df8
-F test/threadtest3.c 655bff6c0895ec03f014126aa65e808fac9aae8c5a7a7da58a510cbe8b43b781
+F test/threadtest3.c 25cb92accb4fa6d53e708d6006ed2db7a7533ef7b838ef1306455c6fe57e978a
 F test/threadtest4.c c1e67136ceb6c7ec8184e56ac61db28f96bd2925
 F test/threadtest5.c 9b4d782c58d8915d7e955ff8051f3d03628bda0d33b82971ea8c0f2f2808c421
 F test/time-wordcount.sh 8e0b0f8109367827ad5d58f5cc849705731e4b90
@@ -1836,12 +1848,13 @@ F test/triggerF.test 5d76f0a8c428ff87a4d5ed52da06f6096a2c787a1e21b846111dfac4123
 F test/triggerG.test 2b816093c91ba73c733cfa8aedcc210ad819d72a98b1da30768a3c56505233e9
 F test/triggerupfrom.test d1f9e56090408115c522bee626cc33a2f3370f627a5e341d832589d72e3aa271
 F test/trustschema1.test d2996bb284859c99956ac706160eab9f086919da738d19bfef3ac431cce8fd47
-F test/tt3_checkpoint.c ac7ca661d739280c89d9c253897df64a59a49369bd1247207ac0f655b622579d
-F test/tt3_index.c 39eec10a35f57672225be4d182862152896dee4a
-F test/tt3_lookaside1.c 0377e202c3c2a50d688cb65ba203afeda6fafeb9
+F test/tt3_checkpoint.c 69214e2ce81bbbd3c1b82c31e103607fd2e6790818aef4792957fc9cc88d067e
+F test/tt3_index.c 95592839426dc85ce5a7a57b41be2cbf3c2ec3457b9cd841a06ed5877f712c7c
+F test/tt3_lookaside1.c 2ddd99bfffeef288f0786827ef68f912f6f47ce3d3184e62f05808d8e13b920e
+F test/tt3_reuseschema.c 4d52e141f89f009028d8ab0bd1f0697d0edffa94bafc1fff0f7ad4d9d9baa549
 F test/tt3_shared.c b37d22defc944a2ac4c91c927fd06c1d48cd51e2ce9d004fe868625bd2399f93
-F test/tt3_stress.c f9a769ca8b026ecc76ee93ca8c9700a5619f8e51c581107c4053ba6ac97f616f
-F test/tt3_vacuum.c 71b254cde1fc49d6c8c44efd54f4668f3e57d7b3a8f4601ade069f75a999ba39
+F test/tt3_stress.c 077e817ac1168443b075fedb44e92db84bb4dc5bd3b6fe1aba25c94ac280b231
+F test/tt3_vacuum.c 727bfda1299b18435eeba80dee8e6ff43462146d7c1e2096cc809f01db568391
 F test/types.test bf816ce73c7dfcfe26b700c19f97ef4050d194ff
 F test/types2.test 1aeb81976841a91eef292723649b5c4fe3bc3cac
 F test/types3.test 99e009491a54f4dc02c06bdbc0c5eea56ae3e25a
@@ -1966,7 +1979,7 @@ F test/whereC.test cae295158703cb3fc23bf1a108a9ab730efff0f6
 F test/whereD.test c1c335e914e28b122e000e9310f02d2be83e1c9dbca2e29f46bd732703944d1b
 F test/whereE.test 7a727b5d5b6bc8fa4cef5206e90cc0363e55ca7f0566f6fbad0206e43170f59e
 F test/whereF.test 926b65519608e3f2aa28720822b9154fb5c7b13519dd78194f434a511ab3dac5
-F test/whereG.test b2a479f425f7d0a432df7e842e8484560908ef703fe0fd407888ff85e7097238
+F test/whereG.test 649d5ad02a87a76ec2ac8de9441e2c83a4dd0f29e459a31215c0533788c6bf07
 F test/whereH.test e4b07f7a3c2f5d31195cd33710054c78667573b2
 F test/whereI.test c4bb7e2ca56d49bd8ab5c7bd085b8b83e353922b46904d68aefb3c7468643581
 F test/whereJ.test fc05e374cc9f2dc204148d6c06822c380ad388895fe97a6d335b94a26a08aecf
@@ -2059,13 +2072,13 @@ F tool/max-limits.c cbb635fbb37ae4d05f240bfb5b5270bb63c54439
 F tool/merge-test.tcl de76b62f2de2a92d4c1ca4f976bce0aea6899e0229e250479b229b2a1914b176
 F tool/mkautoconfamal.sh cbdcf993fa83dccbef7fb77b39cdeb31ef9f77d9d88c9e343b58d35ca3898a6a
 F tool/mkccode.tcl 86463e68ce9c15d3041610fedd285ce32a5cf7a58fc88b3202b8b76837650dbe x
-F tool/mkctimec.tcl 372452e24267dfe1b496eec3992d10c6e5e7d7870a152560cdcfe5404bc8cc04 x
+F tool/mkctimec.tcl a16682eae5f01f85e5861b2aa215ca0d46b4230658ee25977e02b4508566fb75 x
 F tool/mkkeywordhash.c b9faa0ae7e14e4dbbcd951cddd786bf46b8a65bb07b129ba8c0cfade723aaffd
 F tool/mkmsvcmin.tcl 8897d515ef7f94772322db95a3b6fce6c614d84fe0bdd06ba5a1c786351d5a1d
 F tool/mkopcodec.tcl 33d20791e191df43209b77d37f0ff0904620b28465cca6990cf8d60da61a07ef
 F tool/mkopcodeh.tcl 769d9e6a8b462323150dc13a8539d6064664b72974f7894befe2491cc73e05cd
 F tool/mkopts.tcl 680f785fdb09729fd9ac50632413da4eadbdf9071535e3f26d03795828ab07fa
-F tool/mkpragmatab.tcl bd07bd59d45d0f3448e123d6937e9811195f9908a51e09d774609883055bfd3d
+F tool/mkpragmatab.tcl ae506d2d7b22094dc94a0f8cdb612dd4896e87ced649515f1709d784d7bdd595
 F tool/mkshellc.tcl b7adf08b82de60811d2cb6af05ff59fc17e5cd6f3e98743c14eaaa3f8971fed0
 F tool/mksourceid.c 36aa8020014aed0836fd13c51d6dc9219b0df1761d6b5f58ff5b616211b079b9
 F tool/mkspeedsql.tcl a1a334d288f7adfe6e996f2e712becf076745c97
@@ -2106,7 +2119,7 @@ F tool/sqltclsh.c.in 1bcc2e9da58fadf17b0bf6a50e68c1159e602ce057210b655d50bad5aaa
 F tool/sqltclsh.tcl 862f4cf1418df5e1315b5db3b5ebe88969e2a784525af5fbf9596592f14ed848
 F tool/src-verify.c 41c586dee84d0b190ad13e0282ed83d4a65ec9fefde9adf4943efdf6558eea7f
 F tool/srcck1.c 371de5363b70154012955544f86fdee8f6e5326f
-F tool/srctree-check.tcl cef630bc4ff21a460d72479c43a42bf1c1ed61897659305c35c8d72e91bcb176
+F tool/srctree-check.tcl 9f1098d439159692ece45cc9e701b35df4956269399fe0c770e41f235d1ce5e6
 F tool/stack_usage.tcl f8e71b92cdb099a147dad572375595eae55eca43
 F tool/stripccomments.c 20b8aabc4694d0d4af5566e42da1f1a03aff057689370326e9269a9ddcffdc37
 F tool/symbols-mingw.sh 4dbcea7e74768305384c9fd2ed2b41bbf9f0414d
@@ -2139,11 +2152,8 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P d1895dd8f5757a339f619f22b29c8a739398ded673bb9c93f1b8eb8a4b38f510
-R 06db090922d30265c1e1381238ea6702
-T +sym-major-release *
-T +sym-release *
-T +sym-version-3.44.0 *
+P 24fc47afbd6b6b29a247cfe33daa54962aead0b9bb7046fce7e2be705a410e44 ebead0e7230cd33bcec9f95d2183069565b9e709bf745c9b5db65cc0cbf92c0f
+R f0ebd0bea4ca2a42b31a447df251028b
 U drh
-Z 14f36413d8197ea0c35026cb3842c9f7
+Z a0630db0579f1f4d3ee98f53dd45c897
 # Remove this line to create a well-formed Fossil manifest.

manifest.uuid

@@ -1 +1 @@
-17129ba1ff7f0daf37100ee82d507aef7827cf38de1866e2633096ae6ad81301
+2b9d5ff78f085fc465a5a7f2468ded1d15a46ce09edfe6e09bd10fe16f319757

src/alter.c

@@ -112,8 +112,8 @@ static void renameReloadSchema(Parse *pParse, int iDb, u16 p5){
   Vdbe *v = pParse->pVdbe;
   if( v ){
     sqlite3ChangeCookie(pParse, iDb);
-    sqlite3VdbeAddParseSchemaOp(pParse->pVdbe, iDb, 0, p5);
-    if( iDb!=1 ) sqlite3VdbeAddParseSchemaOp(pParse->pVdbe, 1, 0, p5);
+    sqlite3VdbeAddParseSchemaOp(pParse, iDb, 0, p5);
+    if( iDb!=1 ) sqlite3VdbeAddParseSchemaOp(pParse, 1, 0, p5);
   }
 }
 

src/analyze.c

@@ -212,6 +212,7 @@ static void openStatTable(
         ** side-effect of the CREATE TABLE statement is to leave the rootpage 
         ** of the new table in register pParse->regRoot. This is important 
         ** because the OpenWrite opcode below will be needing it. */
+        sqlite3SchemaWritable(pParse, iDb);
         sqlite3NestedParse(pParse,
             "CREATE TABLE %Q.%s(%s)", pDb->zDbSName, zTab, aTable[i].zCols
         );

src/attach.c

@@ -218,14 +218,14 @@ static void attachFunc(
   ** way we found it.
   */
   if( rc==SQLITE_OK ){
-    sqlite3BtreeEnterAll(db);
     db->init.iDb = 0;
     db->mDbFlags &= ~(DBFLAG_SchemaKnownOk);
-    if( !REOPEN_AS_MEMDB(db) ){
+    if( !IsSharedSchema(db) && !REOPEN_AS_MEMDB(db) ){
+      sqlite3BtreeEnterAll(db);
       rc = sqlite3Init(db, &zErrDyn);
+      sqlite3BtreeLeaveAll(db);
+      assert( zErrDyn==0 || rc!=SQLITE_OK );
     }
-    sqlite3BtreeLeaveAll(db);
-    assert( zErrDyn==0 || rc!=SQLITE_OK );
   }
 #ifdef SQLITE_USER_AUTHENTICATION
   if( rc==SQLITE_OK && !REOPEN_AS_MEMDB(db) ){
@@ -325,6 +325,7 @@ static void detachFunc(
     pEntry = sqliteHashNext(pEntry);
   }
 
+  (void)sqlite3SchemaDisconnect(db, i, 0);
   sqlite3BtreeClose(pDb->pBt);
   pDb->pBt = 0;
   pDb->pSchema = 0;
@@ -354,7 +355,9 @@ static void codeAttach(
   sqlite3* db = pParse->db;
   int regArgs;
 
-  if( SQLITE_OK!=sqlite3ReadSchema(pParse) ) goto attach_end;
+  if( (db->mDbFlags & DBFLAG_EncodingFixed)==0 ){
+    if( SQLITE_OK!=sqlite3ReadSchema(pParse) ) goto attach_end;
+  }
 
   if( pParse->nErr ) goto attach_end;
   memset(&sName, 0, sizeof(NameContext));

src/build.c

@@ -338,6 +338,39 @@ int sqlite3UserAuthTable(const char *zTable){
 }
 #endif
 
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+/*
+** If this database connection was opened with the SQLITE_OPEN_SHARED_SCHEMA
+** flag specified, then ensure that the database schema for database iDb
+** is loaded. Either by obtaining a Schema object from the schema-pool, or
+** by reading the contents of the sqlite_master table. Unless it is NULL, 
+** the location indicated by parameter pbUnload is set to 1 if a shared-schema 
+** is loaded.
+**
+** If the database handle was not opened with SQLITE_OPEN_SHARED_SCHEMA, or
+** if the schema for database iDb is already loaded, this function is a no-op.
+**
+** SQLITE_OK is returned if successful, or an SQLite error code otherwise. If
+** an error code is returned, (*pzErr) may be set to point to a buffer
+** containing an error message. It is the responsibility of the caller to
+** eventually free this buffer using sqlite3_free().
+*/
+int sqlite3SchemaLoad(sqlite3 *db, int iDb, int *pbUnload, char **pzErr){
+  int rc = SQLITE_OK;
+  if( IsSharedSchema(db) 
+      && DbHasProperty(db, iDb, DB_SchemaLoaded)==0 
+      && (db->init.busy==0 || (iDb!=1 && db->init.iDb==1))
+  ){
+    struct sqlite3InitInfo sv = db->init;
+    memset(&db->init, 0, sizeof(struct sqlite3InitInfo));
+    rc = sqlite3InitOne(db, iDb, pzErr, 0);
+    db->init = sv;
+    if( pbUnload && rc==SQLITE_OK && iDb!=1 ) *pbUnload = 1;
+  }
+  return rc;
+}
+#endif
+
 /*
 ** Locate the in-memory structure that describes a particular database
 ** table given the name of that table and (optionally) the name of the
@@ -363,59 +396,41 @@ Table *sqlite3FindTable(sqlite3 *db, const char *zName, const char *zDatabase){
     return 0;
   }
 #endif
-  if( zDatabase ){
-    for(i=0; i<db->nDb; i++){
-      if( sqlite3StrICmp(zDatabase, db->aDb[i].zDbSName)==0 ) break;
-    }
-    if( i>=db->nDb ){
-      /* No match against the official names.  But always match "main"
-      ** to schema 0 as a legacy fallback. */
-      if( sqlite3StrICmp(zDatabase,"main")==0 ){
-        i = 0;
-      }else{
-        return 0;
-      }
-    }
-    p = sqlite3HashFind(&db->aDb[i].pSchema->tblHash, zName);
-    if( p==0 && sqlite3StrNICmp(zName, "sqlite_", 7)==0 ){
-      if( i==1 ){
-        if( sqlite3StrICmp(zName+7, &PREFERRED_TEMP_SCHEMA_TABLE[7])==0
-         || sqlite3StrICmp(zName+7, &PREFERRED_SCHEMA_TABLE[7])==0
-         || sqlite3StrICmp(zName+7, &LEGACY_SCHEMA_TABLE[7])==0
-        ){
-          p = sqlite3HashFind(&db->aDb[1].pSchema->tblHash,
-                              LEGACY_TEMP_SCHEMA_TABLE);
+  while(1){
+    for(i=OMIT_TEMPDB; i<db->nDb; i++){
+      int j = (i<2) ? i^1 : i;   /* Search TEMP before MAIN */
+      if( zDatabase==0 || sqlite3DbIsNamed(db, j, zDatabase) ){
+        int bUnload = 0;
+        assert( sqlite3SchemaMutexHeld(db, j, 0) );
+        if( IsSharedSchema(db) ){
+          Parse *pParse = db->pParse;
+          if( pParse && pParse->nErr==0 ){
+            pParse->rc = sqlite3SchemaLoad(db, j, &bUnload, &pParse->zErrMsg);
+            if( pParse->rc ) pParse->nErr++;
+          }
         }
-      }else{
-        if( sqlite3StrICmp(zName+7, &PREFERRED_SCHEMA_TABLE[7])==0 ){
-          p = sqlite3HashFind(&db->aDb[i].pSchema->tblHash,
-                              LEGACY_SCHEMA_TABLE);
+        p = sqlite3HashFind(&db->aDb[j].pSchema->tblHash, zName);
+        if( p ) return p;
+        if( bUnload ){
+          sqlite3SchemaRelease(db, j);
         }
       }
     }
-  }else{
-    /* Match against TEMP first */
-    p = sqlite3HashFind(&db->aDb[1].pSchema->tblHash, zName);
-    if( p ) return p;
-    /* The main database is second */
-    p = sqlite3HashFind(&db->aDb[0].pSchema->tblHash, zName);
-    if( p ) return p;
-    /* Attached databases are in order of attachment */
-    for(i=2; i<db->nDb; i++){
-      assert( sqlite3SchemaMutexHeld(db, i, 0) );
-      p = sqlite3HashFind(&db->aDb[i].pSchema->tblHash, zName);
-      if( p ) break;
+    /* Not found.  If the name we were looking for was temp.sqlite_master
+    ** then change the name to sqlite_temp_master and try again. */
+    if( sqlite3StrICmp(zName, PREFERRED_SCHEMA_TABLE)==0 ){
+      zName = LEGACY_SCHEMA_TABLE;
+      continue;
     }
-    if( p==0 && sqlite3StrNICmp(zName, "sqlite_", 7)==0 ){
-      if( sqlite3StrICmp(zName+7, &PREFERRED_SCHEMA_TABLE[7])==0 ){
-        p = sqlite3HashFind(&db->aDb[0].pSchema->tblHash, LEGACY_SCHEMA_TABLE);
-      }else if( sqlite3StrICmp(zName+7, &PREFERRED_TEMP_SCHEMA_TABLE[7])==0 ){
-        p = sqlite3HashFind(&db->aDb[1].pSchema->tblHash,
-                            LEGACY_TEMP_SCHEMA_TABLE);
-      }
+    if( sqlite3StrICmp(zName, PREFERRED_TEMP_SCHEMA_TABLE)==0 ){
+      zName = LEGACY_TEMP_SCHEMA_TABLE;
+      continue;
     }
+    if( sqlite3StrICmp(zName, LEGACY_SCHEMA_TABLE)!=0 ) break;
+    if( sqlite3_stricmp(zDatabase, db->aDb[1].zDbSName)!=0 ) break;
+    zName = LEGACY_TEMP_SCHEMA_TABLE;
   }
-  return p;
+  return 0;
 }
 
 /*
@@ -440,6 +455,7 @@ Table *sqlite3LocateTable(
   /* Read the database schema. If an error occurs, leave an error message
   ** and code in pParse and return NULL. */
   if( (db->mDbFlags & DBFLAG_SchemaKnownOk)==0
+   && !IsSharedSchema(db)
    && SQLITE_OK!=sqlite3ReadSchema(pParse)
   ){
     return 0;
@@ -456,9 +472,21 @@ Table *sqlite3LocateTable(
       if( pMod==0 && sqlite3_strnicmp(zName, "pragma_", 7)==0 ){
         pMod = sqlite3PragmaVtabRegister(db, zName);
       }
-      if( pMod && sqlite3VtabEponymousTableInit(pParse, pMod) ){
-        testcase( pMod->pEpoTab==0 );
-        return pMod->pEpoTab;
+      if( pMod ){
+        if( IsSharedSchema(db) && pParse->nErr==0 ){
+          int bDummy = 0;
+          pParse->rc = sqlite3SchemaLoad(db, 0, &bDummy, &pParse->zErrMsg);
+          if( pParse->rc ) pParse->nErr++;
+          (void)bDummy;
+        }
+        if( sqlite3VtabEponymousTableInit(pParse, pMod) ){
+          Table *pEpoTab = pMod->pEpoTab;
+          if( pEpoTab ){
+            assert( IsSharedSchema(db)||pEpoTab->pSchema==db->aDb[0].pSchema );
+            pEpoTab->pSchema = db->aDb[0].pSchema;  /* For SHARED_SCHEMA mode */
+          }
+          return pEpoTab;
+        }
       }
     }
 #endif
@@ -468,15 +496,13 @@ Table *sqlite3LocateTable(
     p = 0;
   }
 
-  if( p==0 ){
+  if( p==0 && (!IsSharedSchema(db) || pParse->nErr==0) ){
     const char *zMsg = flags & LOCATE_VIEW ? "no such view" : "no such table";
     if( zDbase ){
       sqlite3ErrorMsg(pParse, "%s: %s.%s", zMsg, zDbase, zName);
     }else{
       sqlite3ErrorMsg(pParse, "%s: %s", zMsg, zName);
     }
-  }else{
-    assert( HasRowid(p) || p->iPKey<0 );
   }
 
   return p;
@@ -645,11 +671,10 @@ void sqlite3ResetOneSchema(sqlite3 *db, int iDb){
     DbSetProperty(db, 1, DB_ResetWanted);
     db->mDbFlags &= ~DBFLAG_SchemaKnownOk;
   }
-
   if( db->nSchemaLock==0 ){
     for(i=0; i<db->nDb; i++){
       if( DbHasProperty(db, i, DB_ResetWanted) ){
-        sqlite3SchemaClear(db->aDb[i].pSchema);
+        sqlite3SchemaClearOrDisconnect(db, i);
       }
     }
   }
@@ -662,16 +687,17 @@ void sqlite3ResetOneSchema(sqlite3 *db, int iDb){
 void sqlite3ResetAllSchemasOfConnection(sqlite3 *db){
   int i;
   sqlite3BtreeEnterAll(db);
-  for(i=0; i<db->nDb; i++){
+  for(i=0; i<db->nDb; i=(i?i+1:2)){
     Db *pDb = &db->aDb[i];
     if( pDb->pSchema ){
       if( db->nSchemaLock==0 ){
-        sqlite3SchemaClear(pDb->pSchema);
+        sqlite3SchemaClearOrDisconnect(db, i);
       }else{
         DbSetProperty(db, i, DB_ResetWanted);
       }
     }
   }
+  sqlite3SchemaClear(db->aDb[1].pSchema);
   db->mDbFlags &= ~(DBFLAG_SchemaChange|DBFLAG_SchemaKnownOk);
   sqlite3VtabUnlockList(db);
   sqlite3BtreeLeaveAll(db);
@@ -1279,7 +1305,7 @@ void sqlite3StartTable(
   */
   if( !IN_SPECIAL_PARSE ){
     char *zDb = db->aDb[iDb].zDbSName;
-    if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
+    if( !IsSharedSchema(db) && SQLITE_OK!=sqlite3ReadSchema(pParse) ){
       goto begin_table_error;
     }
     pTable = sqlite3FindTable(db, zName, zDb);
@@ -2913,7 +2939,7 @@ void sqlite3EndTable(
 #endif
 
     /* Reparse everything to update our internal data structures */
-    sqlite3VdbeAddParseSchemaOp(v, iDb,
+    sqlite3VdbeAddParseSchemaOp(pParse, iDb,
            sqlite3MPrintf(db, "tbl_name='%q' AND type!='trigger'", p->zName),0);
 
     /* Test for cycles in generated columns and illegal expressions
@@ -3482,7 +3508,7 @@ void sqlite3DropTable(Parse *pParse, SrcList *pName, int isView, int noErr){
   }
   assert( pParse->nErr==0 );
   assert( pName->nSrc==1 );
-  if( sqlite3ReadSchema(pParse) ) goto exit_drop_table;
+  if( !IsSharedSchema(db) && sqlite3ReadSchema(pParse) ) goto exit_drop_table;
   if( noErr ) db->suppressErr++;
   assert( isView==0 || isView==LOCATE_VIEW );
   pTab = sqlite3LocateTableItem(pParse, isView, &pName->a[0]);
@@ -3497,6 +3523,7 @@ void sqlite3DropTable(Parse *pParse, SrcList *pName, int isView, int noErr){
   }
   iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
   assert( iDb>=0 && iDb<db->nDb );
+  sqlite3SchemaWritable(pParse, iDb);
 
   /* If pTab is a virtual table, call ViewGetColumnNames() to ensure
   ** it is initialized.
@@ -3951,7 +3978,7 @@ void sqlite3CreateIndex(
   if( IN_DECLARE_VTAB && idxType!=SQLITE_IDXTYPE_PRIMARYKEY ){
     goto exit_create_index;
   }
-  if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
+  if( !IsSharedSchema(db) && SQLITE_OK!=sqlite3ReadSchema(pParse) ){
     goto exit_create_index;
   }
   if( sqlite3HasExplicitNulls(pParse, pList) ){
@@ -4451,7 +4478,7 @@ void sqlite3CreateIndex(
       if( pTblName ){
         sqlite3RefillIndex(pParse, pIndex, iMem);
         sqlite3ChangeCookie(pParse, iDb);
-        sqlite3VdbeAddParseSchemaOp(v, iDb,
+        sqlite3VdbeAddParseSchemaOp(pParse, iDb,
             sqlite3MPrintf(db, "name='%q' AND type='index'", pIndex->zName), 0);
         sqlite3VdbeAddOp2(v, OP_Expire, 0, 1);
       }
@@ -4601,6 +4628,7 @@ void sqlite3DropIndex(Parse *pParse, SrcList *pName, int ifExists){
     goto exit_drop_index;
   }
   iDb = sqlite3SchemaToIndex(db, pIndex->pSchema);
+  sqlite3SchemaWritable(pParse, iDb);
 #ifndef SQLITE_OMIT_AUTHORIZATION
   {
     int code = SQLITE_DROP_INDEX;

src/callback.c

@@ -16,6 +16,63 @@
 
 #include "sqliteInt.h"
 
+/*
+** Connections opened with the SQLITE_OPEN_SHARED_SCHEMA flag specified
+** may use SchemaPool objects for any database that is not the temp db
+** (iDb==1). For such databases (type "struct Db") there are three states
+** the Schema/SchemaPool object may be in.
+**
+**   1) pSPool==0, pSchema points to an empty object allocated by
+**      sqlite3_malloc(). DB_SchemaLoaded flag is clear.
+**
+**   2) pSPool!=0, pSchema points to a populated object owned by the
+**      SchemaPool. DB_SchemaLoaded flag is set.
+**
+**   3) pSPool!=0, pSchema points to the SchemaPool's static object
+**      (SchemaPool.sSchema).
+*/
+struct SchemaPool {
+  int nRef;                       /* Number of pointers to this object */
+  int nDelete;                    /* Schema objects deleted by ReleaseAll() */
+  u64 cksum;                      /* Checksum for this Schema contents */
+  Schema *pSchema;                /* Linked list of Schema objects */
+  Schema sSchema;                 /* The single dummy schema object */
+  SchemaPool *pNext;              /* Next element in schemaPoolList */
+};
+
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+#ifdef SQLITE_DEBUG
+static void assert_schema_state_ok(sqlite3 *db){
+  if( IsSharedSchema(db) && db->eOpenState!=SQLITE_STATE_ZOMBIE ){
+    int i;
+    for(i=0; i<db->nDb; i++){
+      if( i!=1 ){
+        Db *pDb = &db->aDb[i];
+        Btree *pBt = pDb->pBt;
+        if( pBt==0 ) continue;
+        assert( sqlite3BtreeSchema(pBt, 0, 0)==0 );
+        assert( pDb->pSchema );
+        if( pDb->pSPool ){
+          if( DbHasProperty(db, i, DB_SchemaLoaded)==0 ){
+            assert( pDb->pSchema->tblHash.count==0 );
+            assert( pDb->pSchema==&pDb->pSPool->sSchema );
+          }else{
+            assert( pDb->pSchema!=&pDb->pSPool->sSchema );
+          }
+        }else{
+          assert( DbHasProperty(db, i, DB_SchemaLoaded)==0 );
+          assert( pDb->pSchema->tblHash.count==0 );
+          assert( pDb->pSchema!=&pDb->pSPool->sSchema );
+        }
+      }
+    }
+  }
+}
+#else
+# define assert_schema_state_ok(x)
+#endif
+#endif /* ifdef SQLITE_ENABLE_SHARED_SCHEMA */
+
 /*
 ** Invoke the 'collation needed' callback to request a collation sequence
 ** in the encoding enc of name zName, length nName.
@@ -517,15 +574,317 @@ void sqlite3SchemaClear(void *p){
 }
 
 /*
-** Find and return the schema associated with a BTree.  Create
-** a new one if necessary.
+** If this database was opened with the SQLITE_OPEN_SHARED_SCHEMA flag
+** and iDb!=1, then disconnect from the schema-pool associated with
+** database iDb. Otherwise, clear the Schema object belonging to
+** database iDb. 
+**
+** If an OOM error occurs while disconnecting from a schema-pool, 
+** the db->mallocFailed flag is set.
+*/
+void sqlite3SchemaClearOrDisconnect(sqlite3 *db, int iDb){
+  Db *pDb = &db->aDb[iDb];
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+  if( IsSharedSchema(db) && iDb!=1 && pDb->pSPool ){
+    sqlite3SchemaDisconnect(db, iDb, 1);
+  }else
+#endif
+  {
+    sqlite3SchemaClear(pDb->pSchema);
+  }
+}
+
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+/*
+** Global linked list of SchemaPool objects. Read and write access must
+** be protected by the SQLITE_MUTEX_STATIC_MASTER mutex.
+*/
+static SchemaPool *SQLITE_WSD schemaPoolList = 0;
+
+#ifdef SQLITE_TEST
+/*
+** Return a pointer to the head of the linked list of SchemaPool objects.
+** This is used by the virtual table in file test_schemapool.c.
+*/
+SchemaPool *sqlite3SchemaPoolList(void){ return schemaPoolList; }
+#endif
+
+/*
+** Database handle db was opened with the SHARED_SCHEMA flag, and database
+** iDb is currently connected to a schema-pool. When this function is called,
+** (*pnByte) is set to nInit plus the amount of memory used to store a 
+** single instance of the Schema objects managed by the schema-pool.
+** This function adjusts (*pnByte) sot hat it is set to nInit plus
+** (nSchema/nRef) of the amount of memory used by a single Schema object,
+** where nSchema is the number of Schema objects allocated by this pool,
+** and nRef is the number of connections to the schema-pool.
+*/
+void sqlite3SchemaAdjustUsed(sqlite3 *db, int iDb, int nInit, int *pnByte){
+  SchemaPool *pSPool = db->aDb[iDb].pSPool;
+  int nSchema = 0;
+  Schema *p;
+  sqlite3_mutex_enter( sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER) );
+  for(p=pSPool->pSchema; p; p=p->pNext){
+    nSchema++;
+  }
+  *pnByte = nInit + ((*pnByte - nInit) * nSchema) / pSPool->nRef;
+  sqlite3_mutex_leave( sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER) );
+}
+
+/*
+** Check that the schema of db iDb is writable (either because it is the 
+** temp db schema or because the db handle was opened without
+** SQLITE_OPEN_SHARED_SCHEMA). If so, do nothing. Otherwise, leave an 
+** error in the Parse object.
+*/
+void sqlite3SchemaWritable(Parse *pParse, int iDb){
+  if( iDb!=1 && IsSharedSchema(pParse->db) && IN_DECLARE_VTAB==0 ){
+    sqlite3ErrorMsg(pParse, "attempt to modify read-only schema");
+  }
+}
+
+/*
+** The schema object passed as the only argument was allocated using
+** sqlite3_malloc() and then populated using the usual mechanism. This
+** function frees both the Schema object and its contents.
+*/
+static void schemaDelete(Schema *pSchema){
+  sqlite3SchemaClear((void*)pSchema);
+  sqlite3_free(pSchema);
+}
+
+/*
+** When this function is called, the database connection Db must be
+** using a schema-pool (Db.pSPool!=0) and must currently have Db.pSchema
+** set to point to a populated schema object checked out from the 
+** schema-pool. It is also assumed that the STATIC_MASTER mutex is held.
+** This function returns the Schema object to the schema-pool and sets
+** Db.pSchema to point to the schema-pool's static, empty, Schema object.
+*/
+static void schemaRelease(sqlite3 *db, Db *pDb){
+  Schema *pRelease = pDb->pSchema;
+  SchemaPool *pSPool = pDb->pSPool;
+
+  assert( pDb->pSchema->iGeneration==pSPool->sSchema.iGeneration );
+  pDb->pSchema = &pSPool->sSchema;
+
+  assert( pDb->pSPool && pRelease );
+  assert( pRelease->schemaFlags & DB_SchemaLoaded );
+  assert( (pDb->pSchema->schemaFlags & DB_SchemaLoaded)==0 );
+  assert( sqlite3_mutex_held(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER)) );
+
+  /* If the DBFLAG_FreeSchema flag is set and the database connection holds
+  ** at least one other copy of the schema being released, delete it instead
+  ** of returning it to the schema-pool.  */
+  if( db->mDbFlags & DBFLAG_FreeSchema ){
+    int i;
+    for(i=0; i<db->nDb; i++){
+      Db *p = &db->aDb[i];
+      if( p!=pDb && p->pSchema!=&pSPool->sSchema && pDb->pSPool==p->pSPool ){
+        pSPool->nDelete++;
+        schemaDelete(pRelease);
+        return;
+      }
+    }
+  }
+
+  pRelease->pNext = pDb->pSPool->pSchema;
+  pDb->pSPool->pSchema = pRelease;
+}
+
+/*
+** The schema for database iDb of database handle db, which was opened
+** with SQLITE_OPEN_SHARED_SCHEMA, has just been parsed. This function either
+** finds a matching SchemaPool object on the global list (schemaPoolList) or
+** else allocates a new one and sets the Db.pSPool variable accordingly.
+**
+** SQLITE_OK is returned if no error occurs, or an SQLite error code 
+** (SQLITE_NOMEM) otherwise.
+*/
+int sqlite3SchemaConnect(sqlite3 *db, int iDb, u64 cksum){
+  Schema *pSchema = db->aDb[iDb].pSchema;
+  SchemaPool *p;
+
+  assert( pSchema && iDb!=1 && db->aDb[iDb].pSPool==0 );
+
+  sqlite3_mutex_enter( sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER) );
+
+  /* Search for a matching SchemaPool object */
+  for(p=schemaPoolList; p; p=p->pNext){
+    if( p->cksum==cksum && p->sSchema.schema_cookie==pSchema->schema_cookie ){
+      break;
+    }
+  }
+  if( !p ){
+    /* No SchemaPool object found. Allocate a new one. */
+    p = (SchemaPool*)sqlite3_malloc(sizeof(SchemaPool));
+    if( p ){
+      memset(p, 0, sizeof(SchemaPool));
+      p->cksum = cksum;
+      p->pNext = schemaPoolList;
+      schemaPoolList = p;
+
+      p->sSchema.schema_cookie = pSchema->schema_cookie;
+      p->sSchema.iGeneration = pSchema->iGeneration;
+      p->sSchema.file_format = pSchema->file_format;
+      p->sSchema.enc = pSchema->enc;
+      p->sSchema.cache_size = pSchema->cache_size;
+    }
+  }
+
+  if( p ) p->nRef++;
+
+  /* If the SchemaPool contains one or more free schemas at the moment, 
+  ** delete one of them. */
+  if( p && p->pSchema ){
+    Schema *pDel = p->pSchema;
+    p->pSchema = pDel->pNext;
+    schemaDelete(pDel);
+  }
+
+  sqlite3_mutex_leave( sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER) );
+
+  db->aDb[iDb].pSPool = p;
+  return (p ? SQLITE_OK : SQLITE_NOMEM);
+}
+
+/*
+** If parameter iDb is 1 (the temp db), or if connection handle db was not
+** opened with the SQLITE_OPEN_SHARED_SCHEMA flag, this function is a no-op.
+** Otherwise, it disconnects from the schema-pool associated with database
+** iDb, assuming it is connected.
+**
+** If parameter bNew is true, then Db.pSchema is set to point to a new, empty,
+** Schema object obtained from sqlite3_malloc(). Or, if bNew is false, then
+** Db.pSchema is set to NULL before returning.
+**
+** If the bNew parameter is true, then this function may allocate memory. 
+** If the allocation attempt fails, then SQLITE_NOMEM is returned and the
+** schema-pool is not disconnected from. Or, if no OOM error occurs, 
+** SQLITE_OK is returned.
+*/
+int sqlite3SchemaDisconnect(sqlite3 *db, int iDb, int bNew){
+  int rc = SQLITE_OK;
+  if( IsSharedSchema(db) ){
+    Db *pDb = &db->aDb[iDb];
+    SchemaPool *pSPool = pDb->pSPool;
+    assert_schema_state_ok(db);
+    assert( pDb->pSchema );
+
+    if( pSPool==0 ){
+      assert( pDb->pVTable==0 );
+      assert( bNew==0 );
+      schemaDelete(pDb->pSchema);
+      pDb->pSchema = 0;
+    }else{
+      VTable *p;
+      VTable *pNext;
+      for(p=pDb->pVTable; p; p=pNext){
+        pNext = p->pNext;
+        sqlite3VtabUnlock(p);
+      }
+      pDb->pVTable = 0;
+      sqlite3_mutex_enter( sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER) );
+      if( DbHasProperty(db, iDb, DB_SchemaLoaded) ){
+        schemaRelease(db, pDb);
+      }
+      if( bNew ){
+        Schema *pNew = sqlite3SchemaGet(db, 0);
+        if( pNew==0 ){
+          rc = SQLITE_NOMEM;
+        }else{
+          pDb->pSchema = pNew;
+        }
+      }
+      if( rc==SQLITE_OK ){
+        assert( pSPool->nRef>=1 );
+        pDb->pSPool = 0;
+        pSPool->nRef--;
+        if( pSPool->nRef<=0 ){
+          SchemaPool **pp;
+          while( pSPool->pSchema ){
+            Schema *pNext = pSPool->pSchema->pNext;
+            schemaDelete(pSPool->pSchema);
+            pSPool->pSchema = pNext;
+          }
+          for(pp=&schemaPoolList; (*pp)!=pSPool; pp=&((*pp)->pNext));
+          *pp = pSPool->pNext;
+          sqlite3_free(pSPool);
+        }
+      }
+      sqlite3_mutex_leave( sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER) );
+    }
+  }
+  return rc;
+}
+
+/*
+** Extract and return a pointer to a schema object from the SchemaPool passed
+** as the only argument, if one is available. If one is not available, return
+** NULL.
+*/
+Schema *sqlite3SchemaExtract(SchemaPool *pSPool){
+  Schema *pRet = 0;
+  sqlite3_mutex_enter( sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER) );
+  if( pSPool->pSchema ){
+    pRet = pSPool->pSchema;
+    pSPool->pSchema = pRet->pNext;
+    pRet->pNext = 0;
+  }
+  sqlite3_mutex_leave( sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER) );
+  return pRet;
+}
+
+/*
+** Return all sharable schemas held by database handle db back to their
+** respective schema-pools. Db.pSchema variables are left pointing to
+** the static, empty, Schema object owned by each schema-pool.
+*/
+void sqlite3SchemaReleaseAll(sqlite3 *db){
+  int i;
+  assert_schema_state_ok(db);
+  sqlite3_mutex_enter( sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER) );
+  for(i=0; i<db->nDb; i++){
+    if( i!=1 ){
+      Db *pDb = &db->aDb[i];
+      if( pDb->pSPool && DbHasProperty(db,i,DB_SchemaLoaded) ){
+        schemaRelease(db, pDb);
+      }
+    }
+  }
+  db->mDbFlags &= ~DBFLAG_FreeSchema;
+  sqlite3_mutex_leave( sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER) );
+}
+
+/*
+** Release any sharable schema held by connection iDb of database handle
+** db. Db.pSchema is left pointing to the static, empty, Schema object
+** owned by the schema-pool.
+*/
+void sqlite3SchemaRelease(sqlite3 *db, int iDb){
+  Db *pDb = &db->aDb[iDb];
+  assert( iDb!=1 );
+  assert_schema_state_ok(db);
+  sqlite3_mutex_enter( sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER) );
+  schemaRelease(db, pDb);
+  sqlite3_mutex_leave( sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER) );
+}
+
+#endif /* ifdef SQLITE_ENABLE_SHARED_SCHEMA */
+
+/*
+** In most cases, this function finds and returns the schema associated 
+** with BTree handle pBt, creating a new one if necessary. However, if
+** the database handle was opened with the SQLITE_OPEN_SHARED_SCHEMA flag
+** specified, a new, empty, Schema object in memory obtained by 
+** sqlite3_malloc() is always returned.
 */
 Schema *sqlite3SchemaGet(sqlite3 *db, Btree *pBt){
-  Schema * p;
-  if( pBt ){
-    p = (Schema *)sqlite3BtreeSchema(pBt, sizeof(Schema), sqlite3SchemaClear);
+  Schema *p;
+  if( pBt && IsSharedSchema(db)==0 ){
+    p = (Schema*)sqlite3BtreeSchema(pBt, sizeof(Schema), sqlite3SchemaClear);
   }else{
-    p = (Schema *)sqlite3DbMallocZero(0, sizeof(Schema));
+    p = (Schema*)sqlite3DbMallocZero(0, sizeof(Schema));
   }
   if( !p ){
     sqlite3OomFault(db);

src/expr.c

@@ -6043,8 +6043,8 @@ int sqlite3ExprListCompare(const ExprList *pA, const ExprList *pB, int iTab){
 */
 int sqlite3ExprCompareSkip(Expr *pA,Expr *pB, int iTab){
   return sqlite3ExprCompare(0,
-             sqlite3ExprSkipCollateAndLikely(pA),
-             sqlite3ExprSkipCollateAndLikely(pB),
+             sqlite3ExprSkipCollate(pA),
+             sqlite3ExprSkipCollate(pB),
              iTab);
 }
 

src/json.c

@@ -432,13 +432,19 @@ static void jsonAppendNormalizedString(JsonString *p, const char *zIn, u32 N){
   zIn++;
   N -= 2;
   while( N>0 ){
-    for(i=0; i<N && zIn[i]!='\\'; i++){}
+    for(i=0; i<N && zIn[i]!='\\' && zIn[i]!='"'; i++){}
     if( i>0 ){
       jsonAppendRawNZ(p, zIn, i);
       zIn += i;
       N -= i;
       if( N==0 ) break;
     }
+    if( zIn[0]=='"' ){
+      jsonAppendRawNZ(p, "\\\"", 2);
+      zIn++;
+      N--;
+      continue;
+    }
     assert( zIn[0]=='\\' );
     switch( (u8)zIn[1] ){
       case '\'':
@@ -833,7 +839,8 @@ static void jsonReturnJson(
   JsonParse *pParse,          /* The complete JSON */
   JsonNode *pNode,            /* Node to return */
   sqlite3_context *pCtx,      /* Return value for this function */
-  int bGenerateAlt            /* Also store the rendered text in zAlt */
+  int bGenerateAlt,           /* Also store the rendered text in zAlt */
+  int omitSubtype             /* Do not call sqlite3_result_subtype() */
 ){
   JsonString s;
   if( pParse->oom ){
@@ -848,7 +855,7 @@ static void jsonReturnJson(
       pParse->nAlt = s.nUsed;
     }
     jsonResult(&s);
-    sqlite3_result_subtype(pCtx, JSON_SUBTYPE);
+    if( !omitSubtype ) sqlite3_result_subtype(pCtx, JSON_SUBTYPE);
   }
 }
 
@@ -889,7 +896,8 @@ static u32 jsonHexToInt4(const char *z){
 static void jsonReturn(
   JsonParse *pParse,          /* Complete JSON parse tree */
   JsonNode *pNode,            /* Node to return */
-  sqlite3_context *pCtx       /* Return value for this function */
+  sqlite3_context *pCtx,      /* Return value for this function */
+  int omitSubtype             /* Do not call sqlite3_result_subtype() */
 ){
   switch( pNode->eType ){
     default: {
@@ -1035,7 +1043,7 @@ static void jsonReturn(
     }
     case JSON_ARRAY:
     case JSON_OBJECT: {
-      jsonReturnJson(pParse, pNode, pCtx, 0);
+      jsonReturnJson(pParse, pNode, pCtx, 0, omitSubtype);
       break;
     }
   }
@@ -2387,7 +2395,7 @@ static void jsonParseFunc(
   printf("iSubst    = %u\n", p->iSubst);
   printf("iHold     = %u\n", p->iHold);
   jsonDebugPrintNodeEntries(p->aNode, p->nNode);
-  jsonReturnJson(p, p->aNode, ctx, 1);
+  jsonReturnJson(p, p->aNode, ctx, 1, 0);
 }
 
 /*
@@ -2573,15 +2581,14 @@ static void jsonExtractFunc(
       }
       if( pNode ){
         if( flags & JSON_JSON ){
-          jsonReturnJson(p, pNode, ctx, 0);
+          jsonReturnJson(p, pNode, ctx, 0, 0);
         }else{
-          jsonReturn(p, pNode, ctx);
-          sqlite3_result_subtype(ctx, 0);
+          jsonReturn(p, pNode, ctx, 1);
         }
       }
     }else{
       pNode = jsonLookup(p, zPath, 0, ctx);
-      if( p->nErr==0 && pNode ) jsonReturn(p, pNode, ctx);
+      if( p->nErr==0 && pNode ) jsonReturn(p, pNode, ctx, 0);
     }
   }else{
     /* Two or more PATH arguments results in a JSON array with each
@@ -2707,7 +2714,7 @@ static void jsonPatchFunc(
   if( pResult && pX->oom==0 ){
     jsonDebugPrintParse(pX);
     jsonDebugPrintNode(pResult);
-    jsonReturnJson(pX, pResult, ctx, 0);
+    jsonReturnJson(pX, pResult, ctx, 0, 0);
   }else{
     sqlite3_result_error_nomem(ctx);
   }
@@ -2786,7 +2793,7 @@ static void jsonRemoveFunc(
     }
   }
   if( (pParse->aNode[0].jnFlags & JNODE_REMOVE)==0 ){
-    jsonReturnJson(pParse, pParse->aNode, ctx, 1);
+    jsonReturnJson(pParse, pParse->aNode, ctx, 1, 0);
   }
 remove_done:
   jsonDebugPrintParse(p);
@@ -2915,7 +2922,7 @@ static void jsonReplaceFunc(
       jsonReplaceNode(ctx, pParse, (u32)(pNode - pParse->aNode), argv[i+1]);
     }
   }
-  jsonReturnJson(pParse, pParse->aNode, ctx, 1);
+  jsonReturnJson(pParse, pParse->aNode, ctx, 1, 0);
 replace_err:
   jsonDebugPrintParse(pParse);
   jsonParseFree(pParse);
@@ -2969,7 +2976,7 @@ static void jsonSetFunc(
     }
   }
   jsonDebugPrintParse(pParse);
-  jsonReturnJson(pParse, pParse->aNode, ctx, 1);
+  jsonReturnJson(pParse, pParse->aNode, ctx, 1, 0);
 jsonSetDone:
   jsonParseFree(pParse);
 }
@@ -3484,7 +3491,7 @@ static int jsonEachColumn(
     case JEACH_KEY: {
       if( p->i==0 ) break;
       if( p->eType==JSON_OBJECT ){
-        jsonReturn(&p->sParse, pThis, ctx);
+        jsonReturn(&p->sParse, pThis, ctx, 0);
       }else if( p->eType==JSON_ARRAY ){
         u32 iKey;
         if( p->bRecursive ){
@@ -3500,7 +3507,7 @@ static int jsonEachColumn(
     }
     case JEACH_VALUE: {
       if( pThis->jnFlags & JNODE_LABEL ) pThis++;
-      jsonReturn(&p->sParse, pThis, ctx);
+      jsonReturn(&p->sParse, pThis, ctx, 0);
       break;
     }
     case JEACH_TYPE: {
@@ -3511,7 +3518,7 @@ static int jsonEachColumn(
     case JEACH_ATOM: {
       if( pThis->jnFlags & JNODE_LABEL ) pThis++;
       if( pThis->eType>=JSON_ARRAY ) break;
-      jsonReturn(&p->sParse, pThis, ctx);
+      jsonReturn(&p->sParse, pThis, ctx, 0);
       break;
     }
     case JEACH_ID: {
@@ -3804,34 +3811,43 @@ static sqlite3_module jsonTreeModule = {
 void sqlite3RegisterJsonFunctions(void){
 #ifndef SQLITE_OMIT_JSON
   static FuncDef aJsonFunc[] = {
-    JFUNCTION(json,               1, 0,  jsonRemoveFunc),
-    JFUNCTION(json_array,        -1, 0,  jsonArrayFunc),
-    JFUNCTION(json_array_length,  1, 0,  jsonArrayLengthFunc),
-    JFUNCTION(json_array_length,  2, 0,  jsonArrayLengthFunc),
-    JFUNCTION(json_error_position,1, 0,  jsonErrorFunc),
-    JFUNCTION(json_extract,      -1, 0,  jsonExtractFunc),
-    JFUNCTION(->,                 2, JSON_JSON, jsonExtractFunc),
-    JFUNCTION(->>,                2, JSON_SQL, jsonExtractFunc),
-    JFUNCTION(json_insert,       -1, 0,  jsonSetFunc),
-    JFUNCTION(json_object,       -1, 0,  jsonObjectFunc),
-    JFUNCTION(json_patch,         2, 0,  jsonPatchFunc),
-    JFUNCTION(json_quote,         1, 0,  jsonQuoteFunc),
-    JFUNCTION(json_remove,       -1, 0,  jsonRemoveFunc),
-    JFUNCTION(json_replace,      -1, 0,  jsonReplaceFunc),
-    JFUNCTION(json_set,          -1, JSON_ISSET,  jsonSetFunc),
-    JFUNCTION(json_type,          1, 0,  jsonTypeFunc),
-    JFUNCTION(json_type,          2, 0,  jsonTypeFunc),
-    JFUNCTION(json_valid,         1, 0,  jsonValidFunc),
-#if SQLITE_DEBUG
-    JFUNCTION(json_parse,         1, 0,  jsonParseFunc),
-    JFUNCTION(json_test1,         1, 0,  jsonTest1Func),
+    /*                     calls sqlite3_result_subtype()                    */
+    /*                                  |                                    */
+    /*              Uses cache ______   |   __ calls sqlite3_value_subtype() */
+    /*                               |  |  |                                 */
+    /*          Num args _________   |  |  |   ___ Flags                     */
+    /*                            |  |  |  |  |                              */
+    /*                            |  |  |  |  |                              */
+    JFUNCTION(json,               1, 1, 1, 0, 0,          jsonRemoveFunc),
+    JFUNCTION(json_array,        -1, 0, 1, 1, 0,          jsonArrayFunc),
+    JFUNCTION(json_array_length,  1, 1, 0, 0, 0,          jsonArrayLengthFunc),
+    JFUNCTION(json_array_length,  2, 1, 0, 0, 0,          jsonArrayLengthFunc),
+    JFUNCTION(json_error_position,1, 1, 0, 0, 0,          jsonErrorFunc),
+    JFUNCTION(json_extract,      -1, 1, 1, 0, 0,          jsonExtractFunc),
+    JFUNCTION(->,                 2, 1, 1, 0, JSON_JSON,  jsonExtractFunc),
+    JFUNCTION(->>,                2, 1, 0, 0, JSON_SQL,   jsonExtractFunc),
+    JFUNCTION(json_insert,       -1, 1, 1, 1, 0,          jsonSetFunc),
+    JFUNCTION(json_object,       -1, 0, 1, 1, 0,          jsonObjectFunc),
+    JFUNCTION(json_patch,         2, 1, 1, 0, 0,          jsonPatchFunc),
+    JFUNCTION(json_quote,         1, 0, 1, 1, 0,          jsonQuoteFunc),
+    JFUNCTION(json_remove,       -1, 1, 1, 0, 0,          jsonRemoveFunc),
+    JFUNCTION(json_replace,      -1, 1, 1, 1, 0,          jsonReplaceFunc),
+    JFUNCTION(json_set,          -1, 1, 1, 1, JSON_ISSET, jsonSetFunc),
+    JFUNCTION(json_type,          1, 1, 0, 0, 0,          jsonTypeFunc),
+    JFUNCTION(json_type,          2, 1, 0, 0, 0,          jsonTypeFunc),
+    JFUNCTION(json_valid,         1, 1, 0, 0, 0,          jsonValidFunc),
+#ifdef SQLITE_DEBUG
+    JFUNCTION(json_parse,         1, 1, 1, 0, 0,          jsonParseFunc),
+    JFUNCTION(json_test1,         1, 1, 0, 1, 0,          jsonTest1Func),
 #endif
     WAGGREGATE(json_group_array,  1, 0, 0,
        jsonArrayStep, jsonArrayFinal, jsonArrayValue, jsonGroupInverse,
-       SQLITE_SUBTYPE|SQLITE_UTF8|SQLITE_DETERMINISTIC),
+       SQLITE_SUBTYPE|SQLITE_RESULT_SUBTYPE|SQLITE_UTF8|
+       SQLITE_DETERMINISTIC),
     WAGGREGATE(json_group_object, 2, 0, 0,
        jsonObjectStep, jsonObjectFinal, jsonObjectValue, jsonGroupInverse,
-       SQLITE_SUBTYPE|SQLITE_UTF8|SQLITE_DETERMINISTIC)
+       SQLITE_SUBTYPE|SQLITE_RESULT_SUBTYPE|SQLITE_UTF8|
+       SQLITE_DETERMINISTIC)
   };
   sqlite3InsertBuiltinFuncs(aJsonFunc, ArraySize(aJsonFunc));
 #endif

src/main.c

@@ -1214,6 +1214,17 @@ static void disconnectAllVtab(sqlite3 *db){
         if( IsVirtual(pTab) ) sqlite3VtabDisconnect(db, pTab);
       }
     }
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+    if( IsSharedSchema(db) && i!=1 ){
+      VTable *pVTable;
+      VTable *pNext;
+      for(pVTable=db->aDb[i].pVTable; pVTable; pVTable=pNext){
+        pNext = pVTable->pNext;
+        sqlite3VtabUnlock(pVTable);
+      }
+      db->aDb[i].pVTable = 0;
+    }
+#endif /* ifdef SQLITE_ENABLE_SHARED_SCHEMA */
   }
   for(p=sqliteHashFirst(&db->aModule); p; p=sqliteHashNext(p)){
     Module *pMod = (Module *)sqliteHashData(p);
@@ -1390,6 +1401,7 @@ void sqlite3LeaveMutexAndCloseZombie(sqlite3 *db){
       sqlite3BtreeClose(pDb->pBt);
       pDb->pBt = 0;
       if( j!=1 ){
+        (void)sqlite3SchemaDisconnect(db, j, 0);
         pDb->pSchema = 0;
       }
     }
@@ -1914,7 +1926,7 @@ int sqlite3CreateFunc(
   assert( SQLITE_FUNC_CONSTANT==SQLITE_DETERMINISTIC );
   assert( SQLITE_FUNC_DIRECT==SQLITE_DIRECTONLY );
   extraFlags = enc &  (SQLITE_DETERMINISTIC|SQLITE_DIRECTONLY|
-                       SQLITE_SUBTYPE|SQLITE_INNOCUOUS);
+                       SQLITE_SUBTYPE|SQLITE_INNOCUOUS|SQLITE_RESULT_SUBTYPE);
   enc &= (SQLITE_FUNC_ENCMASK|SQLITE_ANY);
 
   /* The SQLITE_INNOCUOUS flag is the same bit as SQLITE_FUNC_UNSAFE.  But
@@ -3923,7 +3935,7 @@ int sqlite3_table_column_metadata(
   int *pPrimaryKey,           /* OUTPUT: True if column part of PK */
   int *pAutoinc               /* OUTPUT: True if column is auto-increment */
 ){
-  int rc;
+  int rc = SQLITE_OK;
   char *zErrMsg = 0;
   Table *pTab = 0;
   Column *pCol = 0;
@@ -3933,7 +3945,7 @@ int sqlite3_table_column_metadata(
   int notnull = 0;
   int primarykey = 0;
   int autoinc = 0;
-
+  int bUnlock;
 
 #ifdef SQLITE_ENABLE_API_ARMOR
   if( !sqlite3SafetyCheckOk(db) || zTableName==0 ){
@@ -3943,14 +3955,29 @@ int sqlite3_table_column_metadata(
 
   /* Ensure the database schema has been loaded */
   sqlite3_mutex_enter(db->mutex);
+  bUnlock = sqlite3LockReusableSchema(db);
   sqlite3BtreeEnterAll(db);
-  rc = sqlite3Init(db, &zErrMsg);
-  if( SQLITE_OK!=rc ){
-    goto error_out;
+  if( IsSharedSchema(db)==0 ){
+    rc = sqlite3Init(db, &zErrMsg);
   }
 
   /* Locate the table in question */
-  pTab = sqlite3FindTable(db, zTableName, zDbName);
+  if( rc==SQLITE_OK ){
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+    Parse sParse;                   /* Fake Parse object for FindTable */
+    Parse *pSaved = db->pParse;
+    memset(&sParse, 0, sizeof(sParse));
+    db->pParse = &sParse;
+#endif
+    pTab = sqlite3FindTable(db, zTableName, zDbName);
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+    sqlite3_free(sParse.zErrMsg);
+    rc = sParse.rc;
+    db->pParse = pSaved;
+#endif
+  }
+  if( SQLITE_OK!=rc ) goto error_out;
+
   if( !pTab || IsView(pTab) ){
     pTab = 0;
     goto error_out;
@@ -4023,6 +4050,7 @@ error_out:
   sqlite3ErrorWithMsg(db, rc, (zErrMsg?"%s":0), zErrMsg);
   sqlite3DbFree(db, zErrMsg);
   rc = sqlite3ApiExit(db, rc);
+  sqlite3UnlockReusableSchema(db, bUnlock);
   sqlite3_mutex_leave(db->mutex);
   return rc;
 }

src/mutex_w32.c

@@ -87,7 +87,7 @@ void sqlite3MemoryBarrier(void){
   SQLITE_MEMORY_BARRIER;
 #elif defined(__GNUC__)
   __sync_synchronize();
-#elif MSVC_VERSION>=1300
+#elif MSVC_VERSION>=1400
   _ReadWriteBarrier();
 #elif defined(MemoryBarrier)
   MemoryBarrier();

src/pager.c

@@ -5062,10 +5062,13 @@ act_like_temp_file:
 */
 sqlite3_file *sqlite3_database_file_object(const char *zName){
   Pager *pPager;
+  const char *p;
   while( zName[-1]!=0 || zName[-2]!=0 || zName[-3]!=0 || zName[-4]!=0 ){
     zName--;
   }
-  pPager = *(Pager**)(zName - 4 - sizeof(Pager*));
+  p = zName - 4 - sizeof(Pager*);
+  assert( EIGHT_BYTE_ALIGNMENT(p) );
+  pPager = *(Pager**)p;
   return pPager->fd;
 }
 

src/pragma.c

@@ -476,7 +476,13 @@ void sqlite3Pragma(
 
   /* Make sure the database schema is loaded if the pragma requires that */
   if( (pPragma->mPragFlg & PragFlg_NeedSchema)!=0 ){
-    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
+    if( IsSharedSchema(db) && (zDb || (pPragma->mPragFlg & PragFlg_OneSchema)) ){
+      assert( iDb>=0 && iDb<db->nDb );
+      pParse->rc = sqlite3SchemaLoad(db, iDb, 0, &pParse->zErrMsg);
+      if( pParse->rc ) goto pragma_out;
+    }else{
+      if( sqlite3ReadSchema(pParse) ) goto pragma_out;
+    }
   }
 
   /* Register the result column names for pragmas that return results */
@@ -2241,9 +2247,10 @@ void sqlite3Pragma(
   ** applications for any purpose.
   */
   case PragTyp_HEADER_VALUE: {
-    int iCookie = pPragma->iArg;  /* Which cookie to read or write */
+    int iCookie;                  /* Which cookie to read or write */
+    iCookie = pPragma->iArg & PRAGMA_HEADER_VALUE_MASK;     
     sqlite3VdbeUsesBtree(v, iDb);
-    if( zRight && (pPragma->mPragFlg & PragFlg_ReadOnly)==0 ){
+    if( zRight && (pPragma->iArg & PRAGMA_HEADER_VALUE_READONLY)==0 ){
       /* Write the specified cookie value */
       static const VdbeOpList setCookie[] = {
         { OP_Transaction,    0,  1,  0},    /* 0 */

src/pragma.h

@@ -56,12 +56,19 @@
 #define PragFlg_NeedSchema 0x01 /* Force schema load before running */
 #define PragFlg_NoColumns  0x02 /* OP_ResultRow called with zero columns */
 #define PragFlg_NoColumns1 0x04 /* zero columns if RHS argument is present */
-#define PragFlg_ReadOnly   0x08 /* Read-only HEADER_VALUE */
+#define PragFlg_OneSchema  0x08 /* Only a single schema required */
 #define PragFlg_Result0    0x10 /* Acts as query when no argument */
 #define PragFlg_Result1    0x20 /* Acts as query when has one argument */
 #define PragFlg_SchemaOpt  0x40 /* Schema restricts name search if present */
 #define PragFlg_SchemaReq  0x80 /* Schema required - "main" is default */
 
+/* For PragTyp_HEADER_VALUE pragmas the Pragma.iArg value is set
+** to the index of the header field to access (always 10 or less).
+** Ored with HEADER_VALUE_READONLY if the field is read only. */
+#define PRAGMA_HEADER_VALUE_READONLY 0x0100
+#define PRAGMA_HEADER_VALUE_MASK 0x00FF
+
+
 /* Names of columns for pragmas that return multi-column result
 ** or that return single-column results where the name of the
 ** result column is different from the name of the pragma
@@ -162,7 +169,7 @@ static const PragmaName aPragmaName[] = {
 #if !defined(SQLITE_OMIT_AUTOVACUUM)
  {/* zName:     */ "auto_vacuum",
   /* ePragTyp:  */ PragTyp_AUTO_VACUUM,
-  /* ePragFlg:  */ PragFlg_NeedSchema|PragFlg_Result0|PragFlg_SchemaReq|PragFlg_NoColumns1,
+  /* ePragFlg:  */ PragFlg_NeedSchema|PragFlg_Result0|PragFlg_SchemaReq|PragFlg_NoColumns1|PragFlg_OneSchema,
   /* ColNames:  */ 0, 0,
   /* iArg:      */ 0 },
 #endif
@@ -183,7 +190,7 @@ static const PragmaName aPragmaName[] = {
 #if !defined(SQLITE_OMIT_PAGER_PRAGMAS)
  {/* zName:     */ "cache_size",
   /* ePragTyp:  */ PragTyp_CACHE_SIZE,
-  /* ePragFlg:  */ PragFlg_NeedSchema|PragFlg_Result0|PragFlg_SchemaReq|PragFlg_NoColumns1,
+  /* ePragFlg:  */ PragFlg_NeedSchema|PragFlg_Result0|PragFlg_SchemaReq|PragFlg_NoColumns1|PragFlg_OneSchema,
   /* ColNames:  */ 0, 0,
   /* iArg:      */ 0 },
 #endif
@@ -244,9 +251,9 @@ static const PragmaName aPragmaName[] = {
 #if !defined(SQLITE_OMIT_SCHEMA_VERSION_PRAGMAS)
  {/* zName:     */ "data_version",
   /* ePragTyp:  */ PragTyp_HEADER_VALUE,
-  /* ePragFlg:  */ PragFlg_ReadOnly|PragFlg_Result0,
+  /* ePragFlg:  */ PragFlg_Result0,
   /* ColNames:  */ 0, 0,
-  /* iArg:      */ BTREE_DATA_VERSION },
+  /* iArg:      */ BTREE_DATA_VERSION|PRAGMA_HEADER_VALUE_READONLY },
 #endif
 #if !defined(SQLITE_OMIT_SCHEMA_PRAGMAS)
  {/* zName:     */ "database_list",
@@ -258,7 +265,7 @@ static const PragmaName aPragmaName[] = {
 #if !defined(SQLITE_OMIT_PAGER_PRAGMAS) && !defined(SQLITE_OMIT_DEPRECATED)
  {/* zName:     */ "default_cache_size",
   /* ePragTyp:  */ PragTyp_DEFAULT_CACHE_SIZE,
-  /* ePragFlg:  */ PragFlg_NeedSchema|PragFlg_Result0|PragFlg_SchemaReq|PragFlg_NoColumns1,
+  /* ePragFlg:  */ PragFlg_NeedSchema|PragFlg_Result0|PragFlg_SchemaReq|PragFlg_NoColumns1|PragFlg_OneSchema,
   /* ColNames:  */ 55, 1,
   /* iArg:      */ 0 },
 #endif
@@ -295,7 +302,7 @@ static const PragmaName aPragmaName[] = {
 #if !defined(SQLITE_OMIT_FOREIGN_KEY)
  {/* zName:     */ "foreign_key_list",
   /* ePragTyp:  */ PragTyp_FOREIGN_KEY_LIST,
-  /* ePragFlg:  */ PragFlg_NeedSchema|PragFlg_Result1|PragFlg_SchemaOpt,
+  /* ePragFlg:  */ PragFlg_NeedSchema|PragFlg_Result1|PragFlg_SchemaOpt|PragFlg_OneSchema,
   /* ColNames:  */ 0, 8,
   /* iArg:      */ 0 },
 #endif
@@ -311,9 +318,9 @@ static const PragmaName aPragmaName[] = {
 #if !defined(SQLITE_OMIT_SCHEMA_VERSION_PRAGMAS)
  {/* zName:     */ "freelist_count",
   /* ePragTyp:  */ PragTyp_HEADER_VALUE,
-  /* ePragFlg:  */ PragFlg_ReadOnly|PragFlg_Result0,
+  /* ePragFlg:  */ PragFlg_Result0,
   /* ColNames:  */ 0, 0,
-  /* iArg:      */ BTREE_FREE_PAGE_COUNT },
+  /* iArg:      */ BTREE_FREE_PAGE_COUNT|PRAGMA_HEADER_VALUE_READONLY },
 #endif
 #if !defined(SQLITE_OMIT_FLAG_PRAGMAS)
  {/* zName:     */ "full_column_names",
@@ -353,7 +360,7 @@ static const PragmaName aPragmaName[] = {
 #if !defined(SQLITE_OMIT_AUTOVACUUM)
  {/* zName:     */ "incremental_vacuum",
   /* ePragTyp:  */ PragTyp_INCREMENTAL_VACUUM,
-  /* ePragFlg:  */ PragFlg_NeedSchema|PragFlg_NoColumns,
+  /* ePragFlg:  */ PragFlg_NeedSchema|PragFlg_NoColumns|PragFlg_OneSchema,
   /* ColNames:  */ 0, 0,
   /* iArg:      */ 0 },
 #endif
@@ -384,7 +391,7 @@ static const PragmaName aPragmaName[] = {
 #if !defined(SQLITE_OMIT_PAGER_PRAGMAS)
  {/* zName:     */ "journal_mode",
   /* ePragTyp:  */ PragTyp_JOURNAL_MODE,
-  /* ePragFlg:  */ PragFlg_NeedSchema|PragFlg_Result0|PragFlg_SchemaReq,
+  /* ePragFlg:  */ PragFlg_NeedSchema|PragFlg_Result0|PragFlg_SchemaReq|PragFlg_OneSchema,
   /* ColNames:  */ 0, 0,
   /* iArg:      */ 0 },
  {/* zName:     */ "journal_size_limit",
@@ -422,7 +429,7 @@ static const PragmaName aPragmaName[] = {
   /* iArg:      */ 0 },
  {/* zName:     */ "max_page_count",
   /* ePragTyp:  */ PragTyp_PAGE_COUNT,
-  /* ePragFlg:  */ PragFlg_NeedSchema|PragFlg_Result0|PragFlg_SchemaReq,
+  /* ePragFlg:  */ PragFlg_NeedSchema|PragFlg_Result0|PragFlg_SchemaReq|PragFlg_OneSchema,
   /* ColNames:  */ 0, 0,
   /* iArg:      */ 0 },
  {/* zName:     */ "mmap_size",
@@ -450,7 +457,7 @@ static const PragmaName aPragmaName[] = {
 #if !defined(SQLITE_OMIT_PAGER_PRAGMAS)
  {/* zName:     */ "page_count",
   /* ePragTyp:  */ PragTyp_PAGE_COUNT,
-  /* ePragFlg:  */ PragFlg_NeedSchema|PragFlg_Result0|PragFlg_SchemaReq,
+  /* ePragFlg:  */ PragFlg_NeedSchema|PragFlg_Result0|PragFlg_SchemaReq|PragFlg_OneSchema,
   /* ColNames:  */ 0, 0,
   /* iArg:      */ 0 },
  {/* zName:     */ "page_size",
@@ -549,14 +556,14 @@ static const PragmaName aPragmaName[] = {
 #if !defined(SQLITE_OMIT_SCHEMA_PRAGMAS) && defined(SQLITE_DEBUG)
  {/* zName:     */ "stats",
   /* ePragTyp:  */ PragTyp_STATS,
-  /* ePragFlg:  */ PragFlg_NeedSchema|PragFlg_Result0|PragFlg_SchemaReq,
+  /* ePragFlg:  */ PragFlg_NeedSchema|PragFlg_Result0|PragFlg_SchemaReq|PragFlg_OneSchema,
   /* ColNames:  */ 33, 5,
   /* iArg:      */ 0 },
 #endif
 #if !defined(SQLITE_OMIT_PAGER_PRAGMAS)
  {/* zName:     */ "synchronous",
   /* ePragTyp:  */ PragTyp_SYNCHRONOUS,
-  /* ePragFlg:  */ PragFlg_NeedSchema|PragFlg_Result0|PragFlg_SchemaReq|PragFlg_NoColumns1,
+  /* ePragFlg:  */ PragFlg_NeedSchema|PragFlg_Result0|PragFlg_SchemaReq|PragFlg_NoColumns1|PragFlg_OneSchema,
   /* ColNames:  */ 0, 0,
   /* iArg:      */ 0 },
 #endif
@@ -645,7 +652,7 @@ static const PragmaName aPragmaName[] = {
   /* iArg:      */ 0 },
  {/* zName:     */ "wal_checkpoint",
   /* ePragTyp:  */ PragTyp_WAL_CHECKPOINT,
-  /* ePragFlg:  */ PragFlg_NeedSchema,
+  /* ePragFlg:  */ PragFlg_NeedSchema|PragFlg_OneSchema,
   /* ColNames:  */ 50, 3,
   /* iArg:      */ 0 },
 #endif

src/prepare.c

@@ -43,6 +43,11 @@ static void corruptSchema(
     pData->rc = SQLITE_ERROR;
   }else if( db->flags & SQLITE_WriteSchema ){
     pData->rc = SQLITE_CORRUPT_BKPT;
+  }else if( IsSharedSchema(db) 
+         && 0==sqlite3StrNICmp(zExtra, "malformed database schema", 17)
+  ){
+    pData->rc = SQLITE_CORRUPT_BKPT;
+    *pData->pzErrMsg = sqlite3DbStrDup(db, zExtra);
   }else{
     char *z;
     const char *zObj = azObj[1] ? azObj[1] : "?";
@@ -53,6 +58,28 @@ static void corruptSchema(
   }
 }
 
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+/*
+** Update the Schema.cksum checksum to account for the database object
+** specified by the three arguments following the first.
+*/
+static void schemaUpdateChecksum(
+  InitData *pData,                /* Schema parse context */
+  const char *zName,              /* Name of new database object */
+  const char *zRoot,              /* Root page of new database object */
+  const char *zSql                /* SQL used to create new database object */
+){
+  int i;
+  u64 cksum = pData->cksum;
+  if( zName ){
+    for(i=0; zName[i]; i++) cksum += (cksum<<3) + zName[i];
+  }
+  if( zRoot ) for(i=0; zRoot[i]; i++) cksum += (cksum<<3) + zRoot[i];
+  if( zSql ) for(i=0; zSql[i]; i++) cksum += (cksum<<3) + zSql[i];
+  pData->cksum = cksum;
+}
+#endif /* ifdef SQLITE_ENABLE_SHARED_SCHEMA */
+
 /*
 ** Check to see if any sibling index (another index on the same table)
 ** of pIndex has the same root page number, and if it does, return true.
@@ -76,6 +103,15 @@ static int sqlite3Prepare(
   sqlite3_stmt **ppStmt,    /* OUT: A pointer to the prepared statement */
   const char **pzTail       /* OUT: End of parsed string */
 );
+static int sqlite3LockAndPrepare(
+  sqlite3 *db,              /* Database handle. */
+  const char *zSql,         /* UTF-8 encoded SQL statement. */
+  int nBytes,               /* Length of zSql in bytes. */
+  u32 prepFlags,            /* Zero or more SQLITE_PREPARE_* flags */
+  Vdbe *pReprepare,         /* VM being reprepared */
+  sqlite3_stmt **ppStmt,    /* OUT: A pointer to the prepared statement */
+  const char **pzTail       /* OUT: End of parsed string */
+);
 
 
 /*
@@ -141,7 +177,11 @@ int sqlite3InitCallback(void *pInit, int argc, char **argv, char **NotUsed){
     db->init.orphanTrigger = 0;
     db->init.azInit = (const char**)argv;
     pStmt = 0;
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+    TESTONLY(rcp = ) sqlite3LockAndPrepare(db, argv[4], -1, 0, 0, &pStmt, 0);
+#else
     TESTONLY(rcp = ) sqlite3Prepare(db, argv[4], -1, 0, 0, &pStmt, 0);
+#endif
     rc = db->errCode;
     assert( (rc&0xFF)==(rcp&0xFF) );
     db->init.iDb = saved_iDb;
@@ -153,7 +193,11 @@ int sqlite3InitCallback(void *pInit, int argc, char **argv, char **NotUsed){
         if( rc > pData->rc ) pData->rc = rc;
         if( rc==SQLITE_NOMEM ){
           sqlite3OomFault(db);
-        }else if( rc!=SQLITE_INTERRUPT && (rc&0xFF)!=SQLITE_LOCKED ){
+        }else if( rc!=SQLITE_INTERRUPT && (rc&0xFF)!=SQLITE_LOCKED
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+               && (rc&0xFF)!=SQLITE_IOERR
+#endif
+        ){
           corruptSchema(pData, argv, sqlite3_errmsg(db));
         }
       }
@@ -184,6 +228,12 @@ int sqlite3InitCallback(void *pInit, int argc, char **argv, char **NotUsed){
       }
     }
   }
+
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+  if( IsSharedSchema(db) && iDb!=1 ){
+    schemaUpdateChecksum(pData, argv[0], argv[1], argv[2]);
+  }
+#endif
   return 0;
 }
 
@@ -211,10 +261,28 @@ int sqlite3InitOne(sqlite3 *db, int iDb, char **pzErrMsg, u32 mFlags){
 
   assert( (db->mDbFlags & DBFLAG_SchemaKnownOk)==0 );
   assert( iDb>=0 && iDb<db->nDb );
-  assert( db->aDb[iDb].pSchema );
+  assert( db->aDb[iDb].pSchema || (IsSharedSchema(db) && iDb!=1) );
   assert( sqlite3_mutex_held(db->mutex) );
   assert( iDb==1 || sqlite3BtreeHoldsMutex(db->aDb[iDb].pBt) );
 
+  pDb = &db->aDb[iDb];
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+  assert( pDb->pSPool==0 || IsSharedSchema(db) );
+  if( pDb->pSPool ){
+    /* See if there is a free schema object in the schema-pool. If not,
+    ** disconnect from said schema pool and continue. This function will
+    ** connect to a (possibly different) schema-pool before returning. */
+    Schema *pNew = sqlite3SchemaExtract(pDb->pSPool);
+    if( pNew ){
+      pDb->pSchema = pNew;
+      return SQLITE_OK;
+    }
+    rc = sqlite3SchemaDisconnect(db, iDb, 1);
+    if( rc!=SQLITE_OK ) goto error_out;
+    assert( pDb->pSchema && pDb->pSPool==0 );
+  }
+#endif
+
   db->init.busy = 1;
 
   /* Construct the in-memory representation schema tables (sqlite_schema or
@@ -235,6 +303,7 @@ int sqlite3InitOne(sqlite3 *db, int iDb, char **pzErrMsg, u32 mFlags){
   initData.pzErrMsg = pzErrMsg;
   initData.mInitFlags = mFlags;
   initData.nInitRow = 0;
+  initData.cksum = 0;
   initData.mxPage = 0;
   sqlite3InitCallback(&initData, 5, (char **)azArg, 0);
   db->mDbFlags &= mask;
@@ -245,7 +314,6 @@ int sqlite3InitOne(sqlite3 *db, int iDb, char **pzErrMsg, u32 mFlags){
 
   /* Create a cursor to hold the database open
   */
-  pDb = &db->aDb[iDb];
   if( pDb->pBt==0 ){
     assert( iDb==1 );
     DbSetProperty(db, 1, DB_SchemaLoaded);
@@ -411,6 +479,10 @@ int sqlite3InitOne(sqlite3 *db, int iDb, char **pzErrMsg, u32 mFlags){
     rc = SQLITE_OK;
   }
 
+  if( rc==SQLITE_OK && iDb!=1 && IsSharedSchema(db) ){
+    rc = sqlite3SchemaConnect(db, iDb, initData.cksum);
+  }
+
   /* Jump here for an error that occurs after successfully allocating
   ** curMain and calling sqlite3BtreeEnter(). For an error that occurs
   ** before that point, jump to error_out.
@@ -432,6 +504,35 @@ error_out:
   return rc;
 }
 
+
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+/*
+** If this is a SHARED_SCHEMA connection and the DBFLAG_SchemaInUse flag
+** is not currently set, set it and return non-zero. Otherwise, return 0.
+*/
+int sqlite3LockReusableSchema(sqlite3 *db){
+  if( IsSharedSchema(db) && (db->mDbFlags & DBFLAG_SchemaInuse)==0 ){
+    db->mDbFlags |= DBFLAG_SchemaInuse;
+    return 1;
+  }
+  return 0;
+}
+#endif /* ifdef SQLITE_ENABLE_SHARED_SCHEMA */
+
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+/*
+** This function is a no-op for non-SHARED_SCHEMA connections, or if bRelease
+** is zero. Otherwise, clear the DBFLAG_SchemaInuse flag and release all
+** schema references currently held.
+*/
+void sqlite3UnlockReusableSchema(sqlite3 *db, int bRelease){
+  if( bRelease ){
+    db->mDbFlags &= ~DBFLAG_SchemaInuse;
+    sqlite3SchemaReleaseAll(db);
+  }
+}
+#endif /* ifdef SQLITE_ENABLE_SHARED_SCHEMA */
+
 /*
 ** Initialize all database files - the main database file, the file
 ** used to store temporary tables, and any additional database files
@@ -442,8 +543,12 @@ error_out:
 ** bit is set in the flags field of the Db structure. 
 */
 int sqlite3Init(sqlite3 *db, char **pzErrMsg){
-  int i, rc;
+  int rc = SQLITE_OK;
+  int bReleaseSchema;
+  int i;
   int commit_internal = !(db->mDbFlags&DBFLAG_SchemaChange);
+
+  bReleaseSchema = sqlite3LockReusableSchema(db);
   
   assert( sqlite3_mutex_held(db->mutex) );
   assert( sqlite3BtreeHoldsMutex(db->aDb[0].pBt) );
@@ -453,20 +558,19 @@ int sqlite3Init(sqlite3 *db, char **pzErrMsg){
   /* Do the main schema first */
   if( !DbHasProperty(db, 0, DB_SchemaLoaded) ){
     rc = sqlite3InitOne(db, 0, pzErrMsg, 0);
-    if( rc ) return rc;
   }
   /* All other schemas after the main schema. The "temp" schema must be last */
-  for(i=db->nDb-1; i>0; i--){
+  for(i=db->nDb-1; rc==SQLITE_OK && i>0; i--){
     assert( i==1 || sqlite3BtreeHoldsMutex(db->aDb[i].pBt) );
     if( !DbHasProperty(db, i, DB_SchemaLoaded) ){
       rc = sqlite3InitOne(db, i, pzErrMsg, 0);
-      if( rc ) return rc;
     }
   }
-  if( commit_internal ){
+  if( rc==SQLITE_OK && commit_internal ){
     sqlite3CommitInternalChanges(db);
   }
-  return SQLITE_OK;
+  sqlite3UnlockReusableSchema(db, bReleaseSchema);
+  return rc;
 }
 
 /*
@@ -478,11 +582,12 @@ int sqlite3ReadSchema(Parse *pParse){
   sqlite3 *db = pParse->db;
   assert( sqlite3_mutex_held(db->mutex) );
   if( !db->init.busy ){
+    db->mDbFlags |= DBFLAG_FreeSchema;      /* For sharable-schema mode */
     rc = sqlite3Init(db, &pParse->zErrMsg);
     if( rc!=SQLITE_OK ){
       pParse->rc = rc;
       pParse->nErr++;
-    }else if( db->noSharedCache ){
+    }else if( db->noSharedCache && !IsSharedSchema(db) ){
       db->mDbFlags |= DBFLAG_SchemaKnownOk;
     }
   }
@@ -508,6 +613,10 @@ static void schemaIsValid(Parse *pParse){
     Btree *pBt = db->aDb[iDb].pBt;     /* Btree database to read cookie from */
     if( pBt==0 ) continue;
 
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+    if( IsSharedSchema(db) && iDb!=1 && db->aDb[iDb].pSPool==0 ) continue;
+#endif
+
     /* If there is not already a read-only (or read-write) transaction opened
     ** on the b-tree database, open one now. If a transaction is opened, it 
     ** will be closed immediately after reading the meta-value. */
@@ -844,6 +953,7 @@ static int sqlite3LockAndPrepare(
 ){
   int rc;
   int cnt = 0;
+  int bReleaseSchema = 0;
 
 #ifdef SQLITE_ENABLE_API_ARMOR
   if( ppStmt==0 ) return SQLITE_MISUSE_BKPT;
@@ -853,6 +963,7 @@ static int sqlite3LockAndPrepare(
     return SQLITE_MISUSE_BKPT;
   }
   sqlite3_mutex_enter(db->mutex);
+  bReleaseSchema = sqlite3LockReusableSchema(db);
   sqlite3BtreeEnterAll(db);
   do{
     /* Make multiple attempts to compile the SQL, until it either succeeds
@@ -863,7 +974,11 @@ static int sqlite3LockAndPrepare(
     if( rc==SQLITE_OK || db->mallocFailed ) break;
   }while( (rc==SQLITE_ERROR_RETRY && (cnt++)<SQLITE_MAX_PREPARE_RETRY)
        || (rc==SQLITE_SCHEMA && (sqlite3ResetOneSchema(db,-1), cnt++)==0) );
+
   sqlite3BtreeLeaveAll(db);
+
+  sqlite3UnlockReusableSchema(db, bReleaseSchema);
+
   rc = sqlite3ApiExit(db, rc);
   assert( (rc&db->errMask)==rc );
   db->busyHandler.nBusy = 0;

src/select.c

@@ -2319,7 +2319,8 @@ void sqlite3SubqueryColumnTypes(
   NameContext sNC;
 
   assert( pSelect!=0 );
-  assert( (pSelect->selFlags & SF_Resolved)!=0 );
+  testcase( (pSelect->selFlags & SF_Resolved)==0 );
+  assert( (pSelect->selFlags & SF_Resolved)!=0 || IN_RENAME_OBJECT );
   assert( pTab->nCol==pSelect->pEList->nExpr || pParse->nErr>0 );
   assert( aff==SQLITE_AFF_NONE || aff==SQLITE_AFF_BLOB );
   if( db->mallocFailed || IN_RENAME_OBJECT ) return;
@@ -6372,10 +6373,11 @@ static void selectAddSubqueryTypeInfo(Walker *pWalker, Select *p){
   SrcList *pTabList;
   SrcItem *pFrom;
 
-  assert( p->selFlags & SF_Resolved );
   if( p->selFlags & SF_HasTypeInfo ) return;
   p->selFlags |= SF_HasTypeInfo;
   pParse = pWalker->pParse;
+  testcase( (p->selFlags & SF_Resolved)==0 );
+  assert( (p->selFlags & SF_Resolved) || IN_RENAME_OBJECT );
   pTabList = p->pSrc;
   for(i=0, pFrom=pTabList->a; i<pTabList->nSrc; i++, pFrom++){
     Table *pTab = pFrom->pTab;
@@ -7397,6 +7399,7 @@ int sqlite3Select(
           TREETRACE(0x1000,pParse,p,
                     ("LEFT-JOIN simplifies to JOIN on term %d\n",i));
           pItem->fg.jointype &= ~(JT_LEFT|JT_OUTER);
+          unsetJoinExpr(p->pWhere, pItem->iCursor, 0);
         }
       }
       if( pItem->fg.jointype & JT_LTORJ ){
@@ -7411,17 +7414,15 @@ int sqlite3Select(
               TREETRACE(0x1000,pParse,p,
                         ("RIGHT-JOIN simplifies to JOIN on term %d\n",j));
               pI2->fg.jointype &= ~(JT_RIGHT|JT_OUTER);
+              unsetJoinExpr(p->pWhere, pI2->iCursor, 1);
             }
           }
         }
-        for(j=pTabList->nSrc-1; j>=i; j--){
+        for(j=pTabList->nSrc-1; j>=0; j--){
           pTabList->a[j].fg.jointype &= ~JT_LTORJ;
           if( pTabList->a[j].fg.jointype & JT_RIGHT ) break;
         }
       }
-      assert( pItem->iCursor>=0 );
-      unsetJoinExpr(p->pWhere, pItem->iCursor,
-                    pTabList->a[0].fg.jointype & JT_LTORJ);
     }
 
     /* No further action if this term of the FROM clause is not a subquery */

src/sqlite.h.in

@@ -614,10 +614,11 @@ int sqlite3_exec(
 #define SQLITE_OPEN_EXRESCODE        0x02000000  /* Extended result codes */
 
 /* Reserved:                         0x00F00000 */
+#define SQLITE_OPEN_SHARED_SCHEMA    0x01000000  /* Ok for sqlite3_open_v2() */
+
 /* Legacy compatibility: */
 #define SQLITE_OPEN_MASTER_JOURNAL   0x00004000  /* VFS only */
 
-
 /*
 ** CAPI3REF: Device Characteristics
 **
@@ -5573,13 +5574,27 @@ int sqlite3_create_window_function(
 ** </dd>
 **
 ** [[SQLITE_SUBTYPE]] <dt>SQLITE_SUBTYPE</dt><dd>
-** The SQLITE_SUBTYPE flag indicates to SQLite that a function may call
+** The SQLITE_SUBTYPE flag indicates to SQLite that a function might call
 ** [sqlite3_value_subtype()] to inspect the sub-types of its arguments.
-** Specifying this flag makes no difference for scalar or aggregate user
-** functions. However, if it is not specified for a user-defined window
-** function, then any sub-types belonging to arguments passed to the window
-** function may be discarded before the window function is called (i.e.
-** sqlite3_value_subtype() will always return 0).
+** This flag instructs SQLite to omit some corner-case optimizations that
+** might disrupt the operation of the [sqlite3_value_subtype()] function,
+** causing it to return zero rather than the correct subtype().
+** SQL functions that invokes [sqlite3_value_subtype()] should have this
+** property.  If the SQLITE_SUBTYPE property is omitted, then the return
+** value from [sqlite3_value_subtype()] might sometimes be zero even though
+** a non-zero subtype was specified by the function argument expression.
+**
+** [[SQLITE_RESULT_SUBTYPE]] <dt>SQLITE_RESULT_SUBTYPE</dt><dd>
+** The SQLITE_RESULT_SUBTYPE flag indicates to SQLite that a function might call
+** [sqlite3_result_subtype()] to cause a sub-type to be associated with its
+** result.
+** Every function that invokes [sqlite3_result_subtype()] should have this
+** property.  If it does not, then the call to [sqlite3_result_subtype()]
+** might become a no-op if the function is used as term in an
+** [expression index].  On the other hand, SQL functions that never invoke
+** [sqlite3_result_subtype()] should avoid setting this property, as the
+** purpose of this property is to disable certain optimizations that are
+** incompatible with subtypes.
 ** </dd>
 ** </dl>
 */
@@ -5587,6 +5602,7 @@ int sqlite3_create_window_function(
 #define SQLITE_DIRECTONLY       0x000080000
 #define SQLITE_SUBTYPE          0x000100000
 #define SQLITE_INNOCUOUS        0x000200000
+#define SQLITE_RESULT_SUBTYPE   0x001000000
 
 /*
 ** CAPI3REF: Deprecated Functions
@@ -5783,6 +5799,12 @@ int sqlite3_value_encoding(sqlite3_value*);
 ** information can be used to pass a limited amount of context from
 ** one SQL function to another.  Use the [sqlite3_result_subtype()]
 ** routine to set the subtype for the return value of an SQL function.
+**
+** Every [application-defined SQL function] that invoke this interface
+** should include the [SQLITE_SUBTYPE] property in the text
+** encoding argument when the function is [sqlite3_create_function|registered].
+** If the [SQLITE_SUBTYPE] property is omitted, then sqlite3_value_subtype()
+** might return zero instead of the upstream subtype in some corner cases.
 */
 unsigned int sqlite3_value_subtype(sqlite3_value*);
 
@@ -5913,14 +5935,22 @@ sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
 ** <li> ^(when sqlite3_set_auxdata() is invoked again on the same
 **       parameter)^, or
 ** <li> ^(during the original sqlite3_set_auxdata() call when a memory
-**      allocation error occurs.)^ </ul>
+**      allocation error occurs.)^
+** <li> ^(during the original sqlite3_set_auxdata() call if the function
+**      is evaluated during query planning instead of during query execution,
+**      as sometimes happens with [SQLITE_ENABLE_STAT4].)^ </ul>
 **
-** Note the last bullet in particular.  The destructor X in
+** Note the last two bullets in particular.  The destructor X in
 ** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the
 ** sqlite3_set_auxdata() interface even returns.  Hence sqlite3_set_auxdata()
 ** should be called near the end of the function implementation and the
 ** function implementation should not make any use of P after
-** sqlite3_set_auxdata() has been called.
+** sqlite3_set_auxdata() has been called.  Furthermore, a call to
+** sqlite3_get_auxdata() that occurs immediately after a corresponding call
+** to sqlite3_set_auxdata() might still return NULL if an out-of-memory
+** condition occurred during the sqlite3_set_auxdata() call or if the
+** function is being evaluated during query planning rather than during
+** query execution.
 **
 ** ^(In practice, auxiliary data is preserved between function calls for
 ** function parameters that are compile-time constants, including literal
@@ -6194,6 +6224,20 @@ int sqlite3_result_zeroblob64(sqlite3_context*, sqlite3_uint64 n);
 ** higher order bits are discarded.
 ** The number of subtype bytes preserved by SQLite might increase
 ** in future releases of SQLite.
+**
+** Every [application-defined SQL function] that invokes this interface
+** should include the [SQLITE_RESULT_SUBTYPE] property in its
+** text encoding argument when the SQL function is
+** [sqlite3_create_function|registered].  If the [SQLITE_RESULT_SUBTYPE]
+** property is omitted from the function that invokes sqlite3_result_subtype(),
+** then in some cases the sqlite3_result_subtype() might fail to set
+** the result subtype.
+**
+** If SQLite is compiled with -DSQLITE_STRICT_SUBTYPE=1, then any
+** SQL function that invokes the sqlite3_result_subtype() interface
+** and that does not have the SQLITE_RESULT_SUBTYPE property will raise
+** an error.  Future versions of SQLite might enable -DSQLITE_STRICT_SUBTYPE=1
+** by default.
 */
 void sqlite3_result_subtype(sqlite3_context*,unsigned int);
 

src/sqliteInt.h

@@ -1286,6 +1286,7 @@ typedef struct Db Db;
 typedef struct DbClientData DbClientData;
 typedef struct DbFixer DbFixer;
 typedef struct Schema Schema;
+typedef struct SchemaPool SchemaPool;
 typedef struct Expr Expr;
 typedef struct ExprList ExprList;
 typedef struct FKey FKey;
@@ -1428,6 +1429,10 @@ struct Db {
   u8 safety_level;     /* How aggressive at syncing data to disk */
   u8 bSyncSet;         /* True if "PRAGMA synchronous=N" has been run */
   Schema *pSchema;     /* Pointer to database schema (possibly shared) */
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+  SchemaPool *pSPool;  /* For REUSE_SCHEMA mode */
+  VTable *pVTable;     /* List of all VTable objects (REUSE_SCHEMA mode only) */
+#endif
 };
 
 /*
@@ -1459,6 +1464,9 @@ struct Schema {
   u8 enc;              /* Text encoding used by this database */
   u16 schemaFlags;     /* Flags associated with this schema */
   int cache_size;      /* Number of pages to use in the cache */
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+  Schema *pNext;       /* Next Schema object SchemaPool (REUSE_SCHEMA) */
+#endif
 };
 
 /*
@@ -1785,6 +1793,12 @@ struct sqlite3 {
 #endif
 };
 
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+# define IsSharedSchema(db) (((db)->openFlags & SQLITE_OPEN_SHARED_SCHEMA)!=0)
+#else
+# define IsSharedSchema(db) 0
+#endif
+
 /*
 ** A macro to discover the encoding of a database.
 */
@@ -1868,6 +1882,9 @@ struct sqlite3 {
 #define DBFLAG_InternalFunc   0x0020  /* Allow use of internal functions */
 #define DBFLAG_EncodingFixed  0x0040  /* No longer possible to change enc. */
 
+#define DBFLAG_SchemaInuse    0x0080  /* Do not release sharable schemas */
+#define DBFLAG_FreeSchema     0x0100  /* Free extra shared schemas on release */
+
 /*
 ** Bits of the sqlite3.dbOptFlags field that are used by the
 ** sqlite3_test_control(SQLITE_TESTCTRL_OPTIMIZATIONS,...) interface to
@@ -2014,14 +2031,15 @@ struct FuncDestructor {
 #define SQLITE_FUNC_SLOCHNG  0x2000 /* "Slow Change". Value constant during a
                                     ** single query - might change over time */
 #define SQLITE_FUNC_TEST     0x4000 /* Built-in testing functions */
-/*                           0x8000 -- available for reuse */
+#define SQLITE_FUNC_RUNONLY  0x8000 /* Cannot be used by valueFromFunction */
 #define SQLITE_FUNC_WINDOW   0x00010000 /* Built-in window-only function */
 #define SQLITE_FUNC_INTERNAL 0x00040000 /* For use by NestedParse() only */
 #define SQLITE_FUNC_DIRECT   0x00080000 /* Not for use in TRIGGERs or VIEWs */
-#define SQLITE_FUNC_SUBTYPE  0x00100000 /* Result likely to have sub-type */
+/* SQLITE_SUBTYPE            0x00100000 // Consumer of subtypes */
 #define SQLITE_FUNC_UNSAFE   0x00200000 /* Function has side effects */
 #define SQLITE_FUNC_INLINE   0x00400000 /* Functions implemented in-line */
 #define SQLITE_FUNC_BUILTIN  0x00800000 /* This is a built-in function */
+/*  SQLITE_RESULT_SUBTYPE    0x01000000 // Generator of subtypes */
 #define SQLITE_FUNC_ANYORDER 0x08000000 /* count/min/max aggregate */
 
 /* Identifier numbers for each in-line function */
@@ -2113,9 +2131,10 @@ struct FuncDestructor {
 #define MFUNCTION(zName, nArg, xPtr, xFunc) \
   {nArg, SQLITE_FUNC_BUILTIN|SQLITE_FUNC_CONSTANT|SQLITE_UTF8, \
    xPtr, 0, xFunc, 0, 0, 0, #zName, {0} }
-#define JFUNCTION(zName, nArg, iArg, xFunc) \
-  {nArg, SQLITE_FUNC_BUILTIN|SQLITE_DETERMINISTIC|\
-   SQLITE_FUNC_CONSTANT|SQLITE_UTF8, \
+#define JFUNCTION(zName, nArg, bUseCache, bWS, bRS, iArg, xFunc) \
+  {nArg, SQLITE_FUNC_BUILTIN|SQLITE_DETERMINISTIC|SQLITE_FUNC_CONSTANT|\
+   SQLITE_UTF8|((bUseCache)*SQLITE_FUNC_RUNONLY)|\
+   ((bRS)*SQLITE_SUBTYPE)|((bWS)*SQLITE_RESULT_SUBTYPE), \
    SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, 0, #zName, {0} }
 #define INLINE_FUNC(zName, nArg, iArg, mFlags) \
   {nArg, SQLITE_FUNC_BUILTIN|\
@@ -2381,6 +2400,9 @@ struct VTable {
   u8 eVtabRisk;             /* Riskiness of allowing hacker access */
   int iSavepoint;           /* Depth of the SAVEPOINT stack */
   VTable *pNext;            /* Next in linked list (see above) */
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+  char *zName;              /* Table name (REUSE_SCHEMA mode) */
+#endif
 };
 
 /* Allowed values for VTable.eVtabRisk
@@ -3994,6 +4016,9 @@ struct Trigger {
   Schema *pTabSchema;     /* Schema containing the table */
   TriggerStep *step_list; /* Link list of trigger program steps             */
   Trigger *pNext;         /* Next trigger associated with the table */
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+  char *zTabSchema;       /* Temp triggers in IsSharedSchema() dbs only */
+#endif
 };
 
 /*
@@ -4130,6 +4155,7 @@ typedef struct {
   int rc;             /* Result code stored here */
   u32 mInitFlags;     /* Flags controlling error messages */
   u32 nInitRow;       /* Number of rows processed */
+  u64 cksum;          /* Schema checksum for REUSE_SCHEMA mode */
   Pgno mxPage;        /* Maximum page number.  0 for no limit. */
 } InitData;
 
@@ -5332,6 +5358,29 @@ void sqlite3DefaultRowEst(Index*);
 void sqlite3RegisterLikeFunctions(sqlite3*, int);
 int sqlite3IsLikeFunction(sqlite3*,Expr*,int*,char*);
 void sqlite3SchemaClear(void *);
+void sqlite3SchemaClearOrDisconnect(sqlite3*, int);
+
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA 
+int sqlite3SchemaConnect(sqlite3*, int, u64);
+int sqlite3SchemaDisconnect(sqlite3 *, int, int);
+Schema *sqlite3SchemaExtract(SchemaPool*);
+int sqlite3SchemaLoad(sqlite3*, int, int*, char**);
+void sqlite3SchemaReleaseAll(sqlite3*);
+void sqlite3SchemaRelease(sqlite3*, int);
+void sqlite3SchemaAdjustUsed(sqlite3*, int, int, int*);
+void sqlite3SchemaWritable(Parse*, int);
+void sqlite3UnlockReusableSchema(sqlite3 *db, int bRelease);
+int sqlite3LockReusableSchema(sqlite3 *db);
+#else
+# define sqlite3SchemaWritable(x,y)
+# define sqlite3UnlockReusableSchema(x,y) (void)(y)
+# define sqlite3LockReusableSchema(x) 0
+# define sqlite3SchemaDisconnect(x,y,z) SQLITE_OK
+# define sqlite3SchemaLoad(w,x,y,z) SQLITE_OK
+# define sqlite3SchemaRelease(y,z)
+# define sqlite3SchemaConnect(x,y,z) SQLITE_OK
+#endif
+
 Schema *sqlite3SchemaGet(sqlite3 *, Btree *);
 int sqlite3SchemaToIndex(sqlite3 *db, Schema *);
 KeyInfo *sqlite3KeyInfoAlloc(sqlite3*,int,int);

src/status.c

@@ -288,13 +288,26 @@ int sqlite3_db_status(
     case SQLITE_DBSTATUS_SCHEMA_USED: {
       int i;                      /* Used to iterate through schemas */
       int nByte = 0;              /* Used to accumulate return value */
+      int bReleaseSchema;
 
       sqlite3BtreeEnterAll(db);
+      bReleaseSchema = sqlite3LockReusableSchema(db);
       db->pnBytesFreed = &nByte;
       assert( db->lookaside.pEnd==db->lookaside.pTrueEnd );
       db->lookaside.pEnd = db->lookaside.pStart;
       for(i=0; i<db->nDb; i++){
-        Schema *pSchema = db->aDb[i].pSchema;
+        Schema *pSchema;
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+        int bUnload = 0;
+        int nUsed = nByte;
+        if( db->aDb[i].pSPool ){
+          char *zDummy = 0;
+          rc = sqlite3SchemaLoad(db, i, &bUnload, &zDummy);
+          sqlite3_free(zDummy);
+          if( rc ) break;
+        }
+#endif /* ifdef SQLITE_ENABLE_SHARED_SCHEMA */
+        pSchema = db->aDb[i].pSchema;
         if( ALWAYS(pSchema!=0) ){
           HashElem *p;
 
@@ -316,7 +329,14 @@ int sqlite3_db_status(
             sqlite3DeleteTable(db, (Table *)sqliteHashData(p));
           }
         }
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+        if( db->aDb[i].pSPool ){
+          if( bUnload ) sqlite3SchemaRelease(db, i);
+          sqlite3SchemaAdjustUsed(db, i, nUsed, &nByte);
+        }
+#endif /* ifdef SQLITE_ENABLE_SHARED_SCHEMA */
       }
+      sqlite3UnlockReusableSchema(db, bReleaseSchema);
       db->pnBytesFreed = 0;
       db->lookaside.pEnd = db->lookaside.pTrueEnd;
       sqlite3BtreeLeaveAll(db);

src/tclsqlite.c

@@ -3727,6 +3727,9 @@ static int sqliteCmdUsage(
     "HANDLE ?FILENAME? ?-vfs VFSNAME? ?-readonly BOOLEAN? ?-create BOOLEAN?"
     " ?-nofollow BOOLEAN?"
     " ?-nomutex BOOLEAN? ?-fullmutex BOOLEAN? ?-uri BOOLEAN?"
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+    " ?-shared-schema BOOLEAN?"
+#endif
   );
   return TCL_ERROR;
 }
@@ -3858,6 +3861,16 @@ static int SQLITE_TCLAPI DbMain(
       }else{
         flags &= ~SQLITE_OPEN_URI;
       }
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+    }else if( strcmp(zArg, "-shared-schema")==0 ){
+      int b;
+      if( Tcl_GetBooleanFromObj(interp, objv[i], &b) ) return TCL_ERROR;
+      if( b ){
+        flags |= SQLITE_OPEN_SHARED_SCHEMA;
+      }else{
+        flags &= ~SQLITE_OPEN_SHARED_SCHEMA;
+      }
+#endif /* ifdef SQLITE_ENABLE_SHARED_SCHEMA */
     }else if( strcmp(zArg, "-translatefilename")==0 ){
       if( Tcl_GetBooleanFromObj(interp, objv[i], &bTranslateFileName) ){
         return TCL_ERROR;

src/test_config.c

@@ -771,6 +771,12 @@ Tcl_SetVar2(interp, "sqlite_options", "mergesort", "1", TCL_GLOBAL_ONLY);
   Tcl_SetVar2(interp, "sqlite_options", "windowfunc", "1", TCL_GLOBAL_ONLY);
 #endif
 
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+  Tcl_SetVar2(interp, "sqlite_options", "sharedschema", "1", TCL_GLOBAL_ONLY);
+#else
+  Tcl_SetVar2(interp, "sqlite_options", "sharedschema", "0", TCL_GLOBAL_ONLY);
+#endif
+
 #define LINKVAR(x) { \
     static const int cv_ ## x = SQLITE_ ## x; \
     Tcl_LinkVar(interp, "SQLITE_" #x, (char *)&(cv_ ## x), \

src/test_schemapool.c

@@ -0,0 +1,282 @@
+/*
+** 2006 June 10
+**
+** 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.
+**
+*************************************************************************
+** Code for testing the virtual table interfaces.  This code
+** is not included in the SQLite library.  It is used for automated
+** testing of the SQLite library.
+*/
+
+/*
+** None of this works unless we have virtual tables.
+*/
+#if !defined(SQLITE_OMIT_VIRTUALTABLE) && defined(SQLITE_TEST)
+
+#include <tcl.h>
+
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+
+#include "sqliteInt.h"
+
+/* The code in this file defines a sqlite3 virtual-table module with
+** the following schema.
+*/
+#define SCHEMAPOOL_SCHEMA \
+"CREATE TABLE x("         \
+"  cksum   INTEGER, "     \
+"  nref    INTEGER, "     \
+"  nschema INTEGER, "     \
+"  ndelete INTEGER  "     \
+")"
+
+#define SCHEMAPOOL_NFIELD 4
+
+typedef struct schemapool_vtab schemapool_vtab;
+typedef struct schemapool_cursor schemapool_cursor;
+
+/* A schema table object */
+struct schemapool_vtab {
+  sqlite3_vtab base;
+};
+
+/* A schema table cursor object */
+struct schemapool_cursor {
+  sqlite3_vtab_cursor base;
+  sqlite3_int64 *aData;
+  int iRow;
+  int nRow;
+};
+
+/*
+** Table destructor for the schema module.
+*/
+static int schemaPoolDestroy(sqlite3_vtab *pVtab){
+  sqlite3_free(pVtab);
+  return 0;
+}
+
+/*
+** Table constructor for the schema module.
+*/
+static int schemaPoolCreate(
+  sqlite3 *db,
+  void *pAux,
+  int argc, const char *const*argv,
+  sqlite3_vtab **ppVtab,
+  char **pzErr
+){
+  int rc = SQLITE_NOMEM;
+  schemapool_vtab *pVtab = sqlite3_malloc(sizeof(schemapool_vtab));
+  if( pVtab ){
+    memset(pVtab, 0, sizeof(schemapool_vtab));
+    rc = sqlite3_declare_vtab(db, SCHEMAPOOL_SCHEMA);
+    if( rc!=SQLITE_OK ){
+      sqlite3_free(pVtab);
+      pVtab = 0;
+    }
+  }
+  *ppVtab = (sqlite3_vtab *)pVtab;
+  return rc;
+}
+
+/*
+** Open a new cursor on the schema table.
+*/
+static int schemaPoolOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
+  int rc = SQLITE_NOMEM;
+  schemapool_cursor *pCur;
+  pCur = sqlite3_malloc(sizeof(schemapool_cursor));
+  if( pCur ){
+    memset(pCur, 0, sizeof(schemapool_cursor));
+    *ppCursor = (sqlite3_vtab_cursor*)pCur;
+    rc = SQLITE_OK;
+  }
+  return rc;
+}
+
+/*
+** Close a schema table cursor.
+*/
+static int schemaPoolClose(sqlite3_vtab_cursor *cur){
+  schemapool_cursor *pCur = (schemapool_cursor*)cur;
+  sqlite3_free(pCur->aData);
+  sqlite3_free(pCur);
+  return SQLITE_OK;
+}
+
+/*
+** Retrieve a column of data.
+*/
+static int schemaPoolColumn(sqlite3_vtab_cursor *cur, sqlite3_context *ctx, int i){
+  schemapool_cursor *pCur = (schemapool_cursor*)cur;
+  assert( i==0 || i==1 || i==2 || i==3 );
+  sqlite3_result_int64(ctx, pCur->aData[pCur->iRow*SCHEMAPOOL_NFIELD + i]);
+  return SQLITE_OK;
+}
+
+/*
+** Retrieve the current rowid.
+*/
+static int schemaPoolRowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){
+  schemapool_cursor *pCur = (schemapool_cursor*)cur;
+  *pRowid = pCur->iRow + 1;
+  return SQLITE_OK;
+}
+
+static int schemaPoolEof(sqlite3_vtab_cursor *cur){
+  schemapool_cursor *pCur = (schemapool_cursor*)cur;
+  return pCur->iRow>=pCur->nRow;
+}
+
+/*
+** Advance the cursor to the next row.
+*/
+static int schemaPoolNext(sqlite3_vtab_cursor *cur){
+  schemapool_cursor *pCur = (schemapool_cursor*)cur;
+  pCur->iRow++;
+  return SQLITE_OK;
+}
+
+struct SchemaPool {
+  int nRef;                       /* Number of pointers to this object */
+  int nDelete;                    /* Schema objects deleted by ReleaseAll() */
+  u64 cksum;                      /* Checksum for this Schema contents */
+  Schema *pSchema;                /* Linked list of Schema objects */
+  Schema sSchema;                 /* The single dummy schema object */
+  SchemaPool *pNext;              /* Next element in schemaPoolList */
+};
+extern SchemaPool *sqlite3SchemaPoolList(void);
+
+/*
+** Reset a schemaPool table cursor.
+*/
+static int schemaPoolFilter(
+  sqlite3_vtab_cursor *pVtabCursor, 
+  int idxNum, const char *idxStr,
+  int argc, sqlite3_value **argv
+){
+  SchemaPool *pSPool;
+  schemapool_cursor *pCur = (schemapool_cursor*)pVtabCursor;
+
+  sqlite3_free(pCur->aData);
+  pCur->aData = 0;
+  pCur->nRow = 0;
+  pCur->iRow = 0;
+
+  for(pSPool = sqlite3SchemaPoolList(); pSPool; pSPool=pSPool->pNext){
+    pCur->nRow++;
+  }
+
+  if( pCur->nRow ){
+    int iRow = 0;
+    int nByte = SCHEMAPOOL_NFIELD * pCur->nRow * sizeof(i64);
+    pCur->aData = (i64*)sqlite3_malloc(nByte);
+    if( pCur->aData==0 ) return SQLITE_NOMEM;
+    for(pSPool = sqlite3SchemaPoolList(); pSPool; pSPool=pSPool->pNext){
+      Schema *p;
+      i64 nSchema = 0;
+      for(p=pSPool->pSchema; p; p=p->pNext){
+        nSchema++;
+      }
+      pCur->aData[0 + iRow*SCHEMAPOOL_NFIELD] = pSPool->cksum;
+      pCur->aData[1 + iRow*SCHEMAPOOL_NFIELD] = (i64)pSPool->nRef;
+      pCur->aData[2 + iRow*SCHEMAPOOL_NFIELD] = nSchema;
+      pCur->aData[3 + iRow*SCHEMAPOOL_NFIELD] = (i64)pSPool->nDelete;
+      iRow++;
+    }
+  }
+
+  return SQLITE_OK;
+}
+
+/*
+** Analyse the WHERE condition.
+*/
+static int schemaPoolBestIndex(sqlite3_vtab *tab, sqlite3_index_info *pIdxInfo){
+  return SQLITE_OK;
+}
+
+/*
+** A virtual table module that merely echos method calls into TCL
+** variables.
+*/
+static sqlite3_module schemaPoolModule = {
+  0,                           /* iVersion */
+  schemaPoolCreate,
+  schemaPoolCreate,
+  schemaPoolBestIndex,
+  schemaPoolDestroy,
+  schemaPoolDestroy,
+  schemaPoolOpen,              /* xOpen - open a cursor */
+  schemaPoolClose,             /* xClose - close a cursor */
+  schemaPoolFilter,            /* xFilter - configure scan constraints */
+  schemaPoolNext,              /* xNext - advance a cursor */
+  schemaPoolEof,               /* xEof */
+  schemaPoolColumn,            /* xColumn - read data */
+  schemaPoolRowid,             /* xRowid - read data */
+  0,                           /* xUpdate */
+  0,                           /* xBegin */
+  0,                           /* xSync */
+  0,                           /* xCommit */
+  0,                           /* xRollback */
+  0,                           /* xFindMethod */
+  0,                           /* xRename */
+};
+
+/*
+** Decode a pointer to an sqlite3 object.
+*/
+extern int getDbPointer(Tcl_Interp *interp, const char *zA, sqlite3 **ppDb);
+
+/*
+** Register the schema virtual table module.
+*/
+static int SQLITE_TCLAPI register_schemapool_module(
+  ClientData clientData, /* Not used */
+  Tcl_Interp *interp,    /* The TCL interpreter that invoked this command */
+  int objc,              /* Number of arguments */
+  Tcl_Obj *CONST objv[]  /* Command arguments */
+){
+  sqlite3 *db;
+  if( objc!=2 ){
+    Tcl_WrongNumArgs(interp, 1, objv, "DB");
+    return TCL_ERROR;
+  }
+  if( getDbPointer(interp, Tcl_GetString(objv[1]), &db) ) return TCL_ERROR;
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+  sqlite3_create_module(db, "schemapool", &schemaPoolModule, 0);
+#endif
+  return TCL_OK;
+}
+
+#endif /* ifdef SQLITE_ENABLE_SHARED_SCHEMA */
+#endif /* !defined(SQLITE_OMIT_VIRTUALTABLE) && defined(SQLITE_TEST) */
+
+/*
+** Register commands with the TCL interpreter.
+*/
+int Sqlitetestschemapool_Init(Tcl_Interp *interp){
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+  static struct {
+     char *zName;
+     Tcl_ObjCmdProc *xProc;
+     void *clientData;
+  } aObjCmd[] = {
+     { "register_schemapool_module", register_schemapool_module, 0 },
+  };
+  int i;
+  for(i=0; i<sizeof(aObjCmd)/sizeof(aObjCmd[0]); i++){
+    Tcl_CreateObjCommand(interp, aObjCmd[i].zName, 
+        aObjCmd[i].xProc, aObjCmd[i].clientData, 0);
+  }
+#endif /* ifdef SQLITE_ENABLE_SHARED_SCHEMA */
+  return TCL_OK;
+}
+

src/test_tclsh.c

@@ -76,6 +76,7 @@ const char *sqlite3TestInit(Tcl_Interp *interp){
   extern int Sqlitetest_malloc_Init(Tcl_Interp*);
   extern int Sqlitetest_mutex_Init(Tcl_Interp*);
   extern int Sqlitetestschema_Init(Tcl_Interp*);
+  extern int Sqlitetestschemapool_Init(Tcl_Interp*);
   extern int Sqlitetestsse_Init(Tcl_Interp*);
   extern int Sqlitetesttclvar_Init(Tcl_Interp*);
   extern int Sqlitetestfs_Init(Tcl_Interp*);
@@ -147,6 +148,7 @@ const char *sqlite3TestInit(Tcl_Interp *interp){
   Sqlitetest_malloc_Init(interp);
   Sqlitetest_mutex_Init(interp);
   Sqlitetestschema_Init(interp);
+  Sqlitetestschemapool_Init(interp);
   Sqlitetesttclvar_Init(interp);
   Sqlitetestfs_Init(interp);
   SqlitetestThread_Init(interp);

src/trigger.c

@@ -52,13 +52,34 @@ Trigger *sqlite3TriggerList(Parse *pParse, Table *pTab){
   Trigger *pList;           /* List of triggers to return */
   HashElem *p;              /* Loop variable for TEMP triggers */
 
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+  char *zSchema = 0;
+  sqlite3 *db = pParse->db;
+  if( IsSharedSchema(db) ){
+    zSchema = db->aDb[sqlite3SchemaToIndex(db, pTab->pSchema)].zDbSName;
+  }
+#endif
+
   assert( pParse->disableTriggers==0 );
   pTmpSchema = pParse->db->aDb[1].pSchema;
   p = sqliteHashFirst(&pTmpSchema->trigHash);
   pList = pTab->pTrigger;
   while( p ){
     Trigger *pTrig = (Trigger *)sqliteHashData(p);
-    if( pTrig->pTabSchema==pTab->pSchema
+
+    int bSchemaMatch;
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+    if( zSchema ){
+      /* Shared-schema */
+      bSchemaMatch = (0==sqlite3StrICmp(pTrig->zTabSchema, zSchema));
+    }else
+#endif
+    {
+      /* Non-shared-schema */
+      bSchemaMatch = (pTrig->pTabSchema==pTab->pSchema);
+    }
+
+    if( bSchemaMatch
      && pTrig->table
      && 0==sqlite3StrICmp(pTrig->table, pTab->zName)
      && (pTrig->pTabSchema!=pTmpSchema || pTrig->bReturning)
@@ -68,7 +89,7 @@ Trigger *sqlite3TriggerList(Parse *pParse, Table *pTab){
     }else if( pTrig->op==TK_RETURNING ){
 #ifndef SQLITE_OMIT_VIRTUALTABLE
       assert( pParse->db->pVtabCtx==0 );
-#endif
+#endif 
       assert( pParse->bReturning );
       assert( &(pParse->u1.pReturning->retTrig) == pTrig );
       pTrig->table = pTab->zName;
@@ -263,6 +284,12 @@ void sqlite3BeginTrigger(
   pTrigger->zName = zName;
   zName = 0;
   pTrigger->table = sqlite3DbStrDup(db, pTableName->a[0].zName);
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+  if( IsSharedSchema(db) && iDb==1 ){
+    int iTabDb = sqlite3SchemaToIndex(db, pTab->pSchema);
+    pTrigger->zTabSchema = sqlite3DbStrDup(db, db->aDb[iTabDb].zDbSName);
+  }
+#endif /* ifdef SQLITE_ENABLE_SHARED_SCHEMA */
   pTrigger->pSchema = db->aDb[iDb].pSchema;
   pTrigger->pTabSchema = pTab->pSchema;
   pTrigger->op = (u8)op;
@@ -386,7 +413,7 @@ void sqlite3FinishTrigger(
        pTrig->table, z);
     sqlite3DbFree(db, z);
     sqlite3ChangeCookie(pParse, iDb);
-    sqlite3VdbeAddParseSchemaOp(v, iDb,
+    sqlite3VdbeAddParseSchemaOp(pParse, iDb,
         sqlite3MPrintf(db, "type='trigger' AND name='%q'", zName), 0);
   }
 
@@ -605,6 +632,9 @@ void sqlite3DeleteTrigger(sqlite3 *db, Trigger *pTrigger){
   sqlite3DeleteTriggerStep(db, pTrigger->step_list);
   sqlite3DbFree(db, pTrigger->zName);
   sqlite3DbFree(db, pTrigger->table);
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+  sqlite3DbFree(db, pTrigger->zTabSchema);
+#endif
   sqlite3ExprDelete(db, pTrigger->pWhen);
   sqlite3IdListDelete(db, pTrigger->pColumns);
   sqlite3DbFree(db, pTrigger);
@@ -676,6 +706,7 @@ void sqlite3DropTriggerPtr(Parse *pParse, Trigger *pTrigger){
 
   iDb = sqlite3SchemaToIndex(pParse->db, pTrigger->pSchema);
   assert( iDb>=0 && iDb<db->nDb );
+  sqlite3SchemaWritable(pParse, iDb);
   pTable = tableOfTrigger(pTrigger);
   assert( (pTable && pTable->pSchema==pTrigger->pSchema) || iDb==1 );
 #ifndef SQLITE_OMIT_AUTHORIZATION
@@ -1175,7 +1206,9 @@ static TriggerPrg *codeRowTrigger(
   int iEndTrigger = 0;        /* Label to jump to if WHEN is false */
   Parse sSubParse;            /* Parse context for sub-vdbe */
 
-  assert( pTrigger->zName==0 || pTab==tableOfTrigger(pTrigger) );
+  assert( pTrigger->zName==0 || IsSharedSchema(pParse->db)
+      || pTab==tableOfTrigger(pTrigger)
+  );
   assert( pTop->pVdbe );
 
   /* Allocate the TriggerPrg and SubProgram objects. To ensure that they
@@ -1282,7 +1315,9 @@ static TriggerPrg *getRowTrigger(
   Parse *pRoot = sqlite3ParseToplevel(pParse);
   TriggerPrg *pPrg;
 
-  assert( pTrigger->zName==0 || pTab==tableOfTrigger(pTrigger) );
+  assert( pTrigger->zName==0 || IsSharedSchema(pParse->db)
+      || pTab==tableOfTrigger(pTrigger) 
+  );
 
   /* It may be that this trigger has already been coded (or is in the
   ** process of being coded). If this is the case, then an entry with

src/vacuum.c

@@ -125,6 +125,7 @@ void sqlite3Vacuum(Parse *pParse, Token *pNm, Expr *pInto){
   }
   if( iDb!=1 ){
     int iIntoReg = 0;
+    sqlite3SchemaWritable(pParse, iDb);
     if( pInto && sqlite3ResolveSelfReference(pParse,0,0,pInto,0)==0 ){
       iIntoReg = ++pParse->nMem;
       sqlite3ExprCode(pParse, pInto, iIntoReg);

src/vdbe.c

@@ -132,11 +132,12 @@ int sqlite3_found_count = 0;
 **   sqlite3CantopenError(lineno)
 */
 static void test_trace_breakpoint(int pc, Op *pOp, Vdbe *v){
-  static int n = 0;
+  static u64 n = 0;
   (void)pc;
   (void)pOp;
   (void)v;
   n++;
+  if( n==LARGEST_UINT64 ) abort(); /* So that n is used, preventing a warning */
 }
 #endif
 
@@ -4069,13 +4070,6 @@ case OP_Transaction: {
    && pOp->p5
    && (iMeta!=pOp->p3 || pDb->pSchema->iGeneration!=pOp->p4.i)
   ){
-    /*
-    ** IMPLEMENTATION-OF: R-03189-51135 As each SQL statement runs, the schema
-    ** version is checked to ensure that the schema has not changed since the
-    ** SQL statement was prepared.
-    */
-    sqlite3DbFree(db, p->zErrMsg);
-    p->zErrMsg = sqlite3DbStrDup(db, "database schema has changed");
     /* If the schema-cookie from the database file matches the cookie
     ** stored with the in-memory representation of the schema, do
     ** not reload the schema from the database file.
@@ -4092,6 +4086,13 @@ case OP_Transaction: {
     if( db->aDb[pOp->p1].pSchema->schema_cookie!=iMeta ){
       sqlite3ResetOneSchema(db, pOp->p1);
     }
+    /*
+    ** IMPLEMENTATION-OF: R-03189-51135 As each SQL statement runs, the schema
+    ** version is checked to ensure that the schema has not changed since the
+    ** SQL statement was prepared.
+    */
+    sqlite3DbFree(db, p->zErrMsg);
+    p->zErrMsg = sqlite3DbStrDup(db, "database schema has changed");
     p->expired = 1;
     rc = SQLITE_SCHEMA;
 
@@ -8183,7 +8184,7 @@ case OP_VCheck: {             /* out2 */
   pTab = pOp->p4.pTab;
   assert( pTab!=0 );
   assert( IsVirtual(pTab) );
-  assert( pTab->u.vtab.p!=0 );
+  if( pTab->u.vtab.p==0 ) break;
   pVtab = pTab->u.vtab.p->pVtab;
   assert( pVtab!=0 );
   pModule = pVtab->pModule;

src/vdbe.h

@@ -228,7 +228,7 @@ VdbeOp *sqlite3VdbeAddOpList(Vdbe*, int nOp, VdbeOpList const *aOp,int iLineno);
 #else
 # define sqlite3ExplainBreakpoint(A,B) /*no-op*/
 #endif
-void sqlite3VdbeAddParseSchemaOp(Vdbe*, int, char*, u16);
+void sqlite3VdbeAddParseSchemaOp(Parse*,int,char*,u16);
 void sqlite3VdbeChangeOpcode(Vdbe*, int addr, u8);
 void sqlite3VdbeChangeP1(Vdbe*, int addr, int P1);
 void sqlite3VdbeChangeP2(Vdbe*, int addr, int P2);

src/vdbeapi.c

@@ -531,6 +531,18 @@ void sqlite3_result_subtype(sqlite3_context *pCtx, unsigned int eSubtype){
 #ifdef SQLITE_ENABLE_API_ARMOR
   if( pCtx==0 ) return;
 #endif
+#if defined(SQLITE_STRICT_SUBTYPE) && SQLITE_STRICT_SUBTYPE+0!=0
+  if( pCtx->pFunc!=0
+   && (pCtx->pFunc->funcFlags & SQLITE_RESULT_SUBTYPE)==0
+  ){
+    char zErr[200];
+    sqlite3_snprintf(sizeof(zErr), zErr,
+                     "misuse of sqlite3_result_subtype() by %s()", 
+                     pCtx->pFunc->zName);
+    sqlite3_result_error(pCtx, zErr, -1);
+    return;
+  }
+#endif /* SQLITE_STRICT_SUBTYPE */
   pOut = pCtx->pOut;
   assert( sqlite3_mutex_held(pOut->db->mutex) );
   pOut->eSubtype = eSubtype & 0xff;

src/vdbeaux.c

@@ -211,10 +211,11 @@ static int growOpArray(Vdbe *v, int nOp){
 **   sqlite3CantopenError(lineno)
 */
 static void test_addop_breakpoint(int pc, Op *pOp){
-  static int n = 0;
+  static u64 n = 0;
   (void)pc;
   (void)pOp;
   n++;
+  if( n==LARGEST_UINT64 ) abort(); /* so that n is used, preventing a warning */
 }
 #endif
 
@@ -560,8 +561,10 @@ void sqlite3VdbeExplainPop(Parse *pParse){
 ** The zWhere string must have been obtained from sqlite3_malloc().
 ** This routine will take ownership of the allocated memory.
 */
-void sqlite3VdbeAddParseSchemaOp(Vdbe *p, int iDb, char *zWhere, u16 p5){
+void sqlite3VdbeAddParseSchemaOp(Parse *pParse, int iDb, char *zWhere, u16 p5){
+  Vdbe *p = pParse->pVdbe;
   int j;
+  sqlite3SchemaWritable(pParse, iDb);
   sqlite3VdbeAddOp4(p, OP_ParseSchema, iDb, 0, 0, zWhere, P4_DYNAMIC);
   sqlite3VdbeChangeP5(p, p5);
   for(j=0; j<p->db->nDb; j++) sqlite3VdbeUsesBtree(p, j);

src/vdbeblob.c

@@ -134,6 +134,7 @@ int sqlite3_blob_open(
   Table *pTab;
   Incrblob *pBlob = 0;
   Parse sParse;
+  int bUnlock;            /* True to unlock reusable schemas before returning */
 
 #ifdef SQLITE_ENABLE_API_ARMOR
   if( ppBlob==0 ){
@@ -150,6 +151,7 @@ int sqlite3_blob_open(
 
   sqlite3_mutex_enter(db->mutex);
 
+  bUnlock = sqlite3LockReusableSchema(db);
   pBlob = (Incrblob *)sqlite3DbMallocZero(db, sizeof(Incrblob));
   while(1){
     sqlite3ParseObjectInit(&sParse,db);
@@ -335,6 +337,7 @@ int sqlite3_blob_open(
   }
 
 blob_open_out:
+  sqlite3UnlockReusableSchema(db, bUnlock);
   if( rc==SQLITE_OK && db->mallocFailed==0 ){
     *ppBlob = (sqlite3_blob *)pBlob;
   }else{

src/vdbemem.c

@@ -1515,7 +1515,7 @@ static int valueFromFunction(
 #endif
   assert( pFunc );
   if( (pFunc->funcFlags & (SQLITE_FUNC_CONSTANT|SQLITE_FUNC_SLOCHNG))==0
-   || (pFunc->funcFlags & SQLITE_FUNC_NEEDCOLL)
+   || (pFunc->funcFlags & (SQLITE_FUNC_NEEDCOLL|SQLITE_FUNC_RUNONLY))!=0
   ){
     return SQLITE_OK;
   }

src/vtab.c

@@ -192,6 +192,24 @@ void sqlite3VtabLock(VTable *pVTab){
 VTable *sqlite3GetVTable(sqlite3 *db, Table *pTab){
   VTable *pVtab;
   assert( IsVirtual(pTab) );
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+  if( IsSharedSchema(db) ){
+    int iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
+    if( iDb!=1 ){
+      VTable **pp;
+      for(pp=&db->aDb[iDb].pVTable; *pp; pp=&(*pp)->pNext){
+        if( sqlite3StrICmp(pTab->zName, (*pp)->zName)==0 ) break;
+      }
+      pVtab = *pp;
+      if( pVtab && pTab->nCol<=0 ){
+        *pp = pVtab->pNext;
+        sqlite3VtabUnlock(pVtab);
+        pVtab = 0;
+      }
+      return pVtab;
+    }
+  }
+#endif /* ifdef SQLITE_ENABLE_SHARED_SCHEMA */
   for(pVtab=pTab->u.vtab.p; pVtab && pVtab->db!=db; pVtab=pVtab->pNext);
   return pVtab;
 }
@@ -500,7 +518,7 @@ void sqlite3VtabFinishParse(Parse *pParse, Token *pEnd){
 
     sqlite3VdbeAddOp0(v, OP_Expire);
     zWhere = sqlite3MPrintf(db, "name=%Q AND sql=%Q", pTab->zName, zStmt);
-    sqlite3VdbeAddParseSchemaOp(v, iDb, zWhere, 0);
+    sqlite3VdbeAddParseSchemaOp(pParse, iDb, zWhere, 0);
     sqlite3DbFree(db, zStmt);
 
     iReg = ++pParse->nMem;
@@ -570,6 +588,7 @@ static int vtabCallConstructor(
   char *zModuleName;
   int iDb;
   VtabCtx *pCtx;
+  int nByte;                      /* Bytes of space to allocate */
 
   assert( IsVirtual(pTab) );
   azArg = (const char *const*)pTab->u.vtab.azArg;
@@ -589,7 +608,11 @@ static int vtabCallConstructor(
     return SQLITE_NOMEM_BKPT;
   }
 
-  pVTable = sqlite3MallocZero(sizeof(VTable));
+  nByte = sizeof(VTable);
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+  nByte += sqlite3Strlen30(pTab->zName) + 1;
+#endif
+  pVTable = (VTable*)sqlite3MallocZero(nByte);
   if( !pVTable ){
     sqlite3OomFault(db);
     sqlite3DbFree(db, zModuleName);
@@ -597,6 +620,10 @@ static int vtabCallConstructor(
   }
   pVTable->db = db;
   pVTable->pMod = pMod;
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+  pVTable->zName = (char*)&pVTable[1];
+  memcpy(pVTable->zName, pTab->zName, nByte-sizeof(VTable));
+#endif
   pVTable->eVtabRisk = SQLITE_VTABRISK_Normal;
 
   iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
@@ -641,12 +668,23 @@ static int vtabCallConstructor(
       int iCol;
       u16 oooHidden = 0;
       /* If everything went according to plan, link the new VTable structure
-      ** into the linked list headed by pTab->u.vtab.p. Then loop through the
-      ** columns of the table to see if any of them contain the token "hidden".
-      ** If so, set the Column COLFLAG_HIDDEN flag and remove the token from
-      ** the type string.  */
-      pVTable->pNext = pTab->u.vtab.p;
-      pTab->u.vtab.p = pVTable;
+      ** into the linked list headed by pTab->u.vtab.p. Or, if this is a
+      ** reusable schema, into the linked list headed by Db.pVTable.
+      **
+      ** Then loop through the columns of the table to see if any of them
+      ** contain the token "hidden". If so, set the Column COLFLAG_HIDDEN flag
+      ** and remove the token from the type string.  */
+#ifdef SQLITE_ENABLE_SHARED_SCHEMA
+      if( IsSharedSchema(db) && iDb!=1 ){
+        pVTable->pNext = db->aDb[iDb].pVTable;
+        db->aDb[iDb].pVTable = pVTable;
+      }else
+#endif /* ifdef SQLITE_ENABLE_SHARED_SCHEMA */
+      {
+        assert( IsVirtual(pTab) );
+        pVTable->pNext = pTab->u.vtab.p;
+        pTab->u.vtab.p = pVTable;
+      }
 
       for(iCol=0; iCol<pTab->nCol; iCol++){
         char *zType = sqlite3ColumnType(&pTab->aCol[iCol], "");
@@ -701,6 +739,7 @@ int sqlite3VtabCallConnect(Parse *pParse, Table *pTab){
   assert( pTab );
   assert( IsVirtual(pTab) );
   if( sqlite3GetVTable(db, pTab) ){
+    assert( !IsVirtual(pTab) || pTab->nCol>0 );
     return SQLITE_OK;
   }
 

src/where.c

@@ -1498,7 +1498,7 @@ static int vtabBestIndex(Parse *pParse, Table *pTab, sqlite3_index_info *p){
       sqlite3ErrorMsg(pParse, "%s", pVtab->zErrMsg);
     }
   }
-  if( pTab->u.vtab.p->bAllSchemas ){
+  if( pTab->u.vtab.p && pTab->u.vtab.p->bAllSchemas ){
     sqlite3VtabUsesAllSchemas(pParse);
   }
   sqlite3_free(pVtab->zErrMsg);
@@ -5810,6 +5810,20 @@ static SQLITE_NOINLINE void whereAddIndexedExpr(
       continue;
     }
     if( sqlite3ExprIsConstant(pExpr) ) continue;
+    if( pExpr->op==TK_FUNCTION ){
+      /* Functions that might set a subtype should not be replaced by the
+      ** value taken from an expression index since the index omits the
+      ** subtype.  https://sqlite.org/forum/forumpost/68d284c86b082c3e */
+      int n;
+      FuncDef *pDef;
+      sqlite3 *db = pParse->db;
+      assert( ExprUseXList(pExpr) );
+      n = pExpr->x.pList ? pExpr->x.pList->nExpr : 0;
+      pDef = sqlite3FindFunction(db, pExpr->u.zToken, n, ENC(db), 0);
+      if( pDef==0 || (pDef->funcFlags & SQLITE_RESULT_SUBTYPE)!=0 ){
+        continue;
+      }
+    }
     p = sqlite3DbMallocRaw(pParse->db,  sizeof(IndexedExpr));
     if( p==0 ) break;
     p->pIENext = pParse->pIdxEpr;

src/window.c

@@ -1038,7 +1038,7 @@ int sqlite3WindowRewrite(Parse *pParse, Select *p){
       assert( ExprUseXList(pWin->pOwner) );
       assert( pWin->pWFunc!=0 );
       pArgs = pWin->pOwner->x.pList;
-      if( pWin->pWFunc->funcFlags & SQLITE_FUNC_SUBTYPE ){
+      if( pWin->pWFunc->funcFlags & SQLITE_SUBTYPE ){
         selectWindowRewriteEList(pParse, pMWin, pSrc, pArgs, pTab, &pSublist);
         pWin->iArgCol = (pSublist ? pSublist->nExpr : 0);
         pWin->bExprArgs = 1;

test/alter.test

@@ -954,4 +954,33 @@ do_catchsql_test alter-20.3 {
   INSERT INTO t1(a) VALUES(45);
 } {1 {cannot store BLOB value in TEXT column t1.b}}
 
+# 2023-11-17 dbsqlfuzz e0900262dadd5c78c2226ad6a435c7f0255be2cd
+# Assertion fault associated with ALTER TABLE and an
+# aggregate ORDER BY within an unknown aggregate function.
+#
+reset_db
+do_execsql_test alter-21.1 {
+  CREATE TABLE t1(a,b,c,d);
+  CREATE TABLE t2(a,b,c,d,x);
+  CREATE TRIGGER r1 AFTER INSERT ON t2 BEGIN
+    SELECT unknown_function(a ORDER BY (SELECT group_concat(DISTINCT a ORDER BY a) FROM t1)) FROM t1;
+  END;
+  ALTER TABLE t2 RENAME TO e;
+} {}
+do_execsql_test alter-21.2 {
+  SELECT name, type FROM sqlite_schema ORDER BY name;
+} {e table r1 trigger t1 table}
+do_execsql_test alter-21.3 {
+  DROP TRIGGER r1;
+  CREATE TRIGGER r2 AFTER INSERT ON e BEGIN
+    SELECT unknown_function(a ORDER BY (SELECT group_concat(a ORDER BY a) FROM (SELECT b FROM t1))) FROM t1;
+  END;
+  ALTER TABLE e RENAME TO t99;
+}
+do_execsql_test alter-21.4 {
+  SELECT name, type FROM sqlite_schema ORDER BY name;
+} {r2 trigger t1 table t99 table}
+
+
+
 finish_test

test/indexexpr1.test

@@ -616,4 +616,18 @@ do_execsql_test indexexpr1-2200 {
          ) v ON v.type = 0 AND v.tag = u.tag;
 } {7 100 8 101}
 
+# 2023-11-08 Forum post https://sqlite.org/forum/forumpost/68d284c86b082c3e
+#
+# Functions that return subtypes and that are indexed cannot be used to
+# cover function calls from the main table, since the indexed value does
+# not know the subtype.
+#
+reset_db
+do_execsql_test indexexpr1-2300 {
+  CREATE TABLE t1(x INT, y TEXT);
+  INSERT INTO t1(x,y) VALUES(1,'{b:5}');
+  CREATE INDEX t1j ON t1(json(y));
+  SELECT json_insert('{}', '$.a', json(y)) FROM t1;
+} {{{"a":{"b":5}}}}
+
 finish_test

test/joinH.test

@@ -250,5 +250,63 @@ do_catchsql_test 9.11 {
   SELECT oid FROM wo2 JOIN (wo3 JOIN x3)
 } {0 99}
 
+reset_db
+do_execsql_test 10.0 {
+  CREATE TABLE rt0 (c0 INTEGER, c1 INTEGER, c2 INTEGER, c3 INTEGER, c4 INTEGER);
+  CREATE TABLE rt3 (c3 INTEGER);
+
+  INSERT INTO rt0(c3, c1) VALUES (x'', '1');
+  INSERT INTO rt0(c3, c1) VALUES ('-1', -1e500);
+  INSERT INTO rt0(c3, c1) VALUES (1, x'');
+
+  CREATE VIEW v6(c0, c1, c2) AS SELECT 0, 0, 0;
+}
+
+do_execsql_test 10.1 {
+  SELECT COUNT(*) FROM rt0 LEFT JOIN rt3 JOIN v6 ON ((CASE v6.c0 WHEN rt0.c4 THEN rt3.c3 END) NOT BETWEEN (rt0.c4) AND (NULL)) WHERE (rt0.c1); -- 2
+} {0}
+
+do_execsql_test 10.2 {
+  SELECT COUNT(*) FROM rt0 LEFT JOIN rt3 RIGHT OUTER JOIN v6 ON ((CASE v6.c0 WHEN rt0.c4 THEN rt3.c3 END) NOT BETWEEN (rt0.c4) AND (NULL)) WHERE (rt0.c1); -- 2
+} {0}
+
+#-------------------------------------------------------------------------
+
+do_execsql_test 11.1 {
+  CREATE TABLE t1(a, b);
+  CREATE TABLE t2(c, d);
+  CREATE TABLE t3(e, f);
+
+  INSERT INTO t1 VALUES(1, 1);
+  INSERT INTO t2 VALUES(2, 2);
+  INSERT INTO t3 VALUES(3, 3);
+}
+
+do_execsql_test 11.2 {
+  SELECT * FROM t1 LEFT JOIN t2 RIGHT JOIN t3 ON (t2.c=10)
+} {{} {} {} {} 3 3}
+
+do_execsql_test 11.3 {
+  SELECT * FROM t1 LEFT JOIN t2 RIGHT JOIN t3 ON (t2.c=10) WHERE t1.a=1
+} {}
+
+#-------------------------------------------------------------------------
+reset_db
+
+do_execsql_test 12.1 {
+  CREATE TABLE t1(a1 INT, b1 TEXT);
+  INSERT INTO t1 VALUES(88,'');
+  CREATE TABLE t2(c2 INT, d2 TEXT);
+  INSERT INTO t2 VALUES(88,'');
+  CREATE TABLE t3(e3 TEXT PRIMARY KEY);
+  INSERT INTO t3 VALUES('');
+}
+
+do_execsql_test 12.2 {
+  SELECT * FROM t1 LEFT JOIN t2 ON true RIGHT JOIN t3 ON d2=e3 WHERE c2 BETWEEN NULL AND a1;
+}
+do_execsql_test 12.3 {
+  SELECT * FROM t1 LEFT JOIN t2 ON true RIGHT JOIN t3 ON d2=e3 WHERE c2 BETWEEN NULL AND a1;
+}
 
 finish_test

test/json501.test

@@ -300,5 +300,10 @@ do_execsql_test 12.4 {
           || ' "xyz"}')->>'a';
 } xyz
 
+# 2023-11-08 forum/forumpost/ddcad3e884
+#
+do_execsql_test 13.1 {
+  SELECT json('{x:''a "b" c''}');
+} {{{"x":"a \"b\" c"}}}
 
 finish_test

test/reuse1.test

@@ -0,0 +1,394 @@
+# 2017 August 9
+#
+# 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.
+#
+#***********************************************************************
+#
+#
+
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+set testprefix reuse1
+
+ifcapable !sharedschema {
+  finish_test
+  return
+}
+
+forcedelete test.db2
+sqlite3 db2 test.db2
+
+do_execsql_test 1.0 {
+  CREATE TABLE t1(x INTEGER PRIMARY KEY, y UNIQUE, z);
+  CREATE INDEX i1 ON t1(z);
+  PRAGMA schema_version;
+} {2}
+
+do_execsql_test -db db2 1.1 {
+  CREATE TABLE t1(x INTEGER PRIMARY KEY, y UNIQUE, z);
+  CREATE INDEX i1 ON t1(z);
+  PRAGMA schema_version;
+} {2}
+
+do_test 1.2 {
+  db close
+  db2 close
+  sqlite3 db2 test.db2 -shared-schema 1
+  sqlite3 db  test.db -shared-schema 1
+} {}
+
+do_execsql_test -db db2 1.3.1 {
+  INSERT INTO t1 VALUES(1, 2, 3);
+  INSERT INTO t1 VALUES(4, 5, 6);
+}
+
+do_execsql_test 1.3.2 {
+  SELECT * FROM t1;
+  PRAGMA integrity_check;
+} {ok}
+
+do_execsql_test -db db2 1.3.3 {
+  SELECT * FROM t1;
+  PRAGMA integrity_check;
+} {1 2 3 4 5 6 ok}
+
+sqlite3 db3 test.db2
+do_execsql_test -db db3 1.4.1 {
+  ALTER TABLE t1 ADD COLUMN a;
+}
+do_execsql_test -db db2 1.4.2 {
+  SELECT * FROM t1;
+} {1 2 3 {} 4 5 6 {}}
+do_execsql_test 1.4.3 {
+  SELECT * FROM t1;
+} {}
+
+db3 close
+sqlite3 db3 test.db
+do_execsql_test -db db3 1.5.0 {
+  CREATE TRIGGER tr1 AFTER INSERT ON t1 BEGIN
+    SELECT 1, 2, 3;
+  END;
+}
+
+# Check that the schema cannot be modified if the db was opened with
+# SQLITE_OPEN_REUSE_SCHEMA.
+#
+foreach {tn sql} {
+  1  { CREATE TABLE t2(x, y) }
+  2  { CREATE INDEX i2 ON t1(z) }
+  3  { CREATE VIEW v2 AS SELECT * FROM t2 }
+  4  { ALTER TABLE t1 RENAME TO t3 }
+  5  { ALTER TABLE t1 ADD COLUMN xyz }
+  6  { VACUUM }
+  7  { DROP INDEX i1 }
+  8  { DROP TABLE t1 }
+  9  { DROP TRIGGER tr1 }
+  10 { ANALYZE }
+  11 { ALTER TABLE t1 RENAME z TO zzz }
+} {
+  do_catchsql_test 1.5.$tn $sql {1 {attempt to modify read-only schema}}
+}
+
+#-------------------------------------------------------------------------
+#
+reset_db
+forcedelete test.db2
+ifcapable fts5 {
+  do_execsql_test 2.0 {
+    CREATE VIRTUAL TABLE ft USING fts5(a);
+    INSERT INTO ft VALUES('one'), ('two'), ('three');
+    ATTACH 'test.db2' AS aux;
+    CREATE VIRTUAL TABLE aux.ft USING fts5(a);
+    INSERT INTO aux.ft VALUES('aux1'), ('aux2'), ('aux3');
+  }
+
+  db close
+  sqlite3 db  test.db -shared-schema 1
+
+  do_execsql_test 2.1 {
+    ATTACH 'test.db2' AS aux;
+    SELECT * FROM main.ft;
+  } {one two three}
+
+breakpoint
+  do_execsql_test 2.2 {
+    SELECT * FROM aux.ft;
+  } {aux1 aux2 aux3}
+
+  do_execsql_test 2.2 {
+    SELECT * FROM aux.ft_content;
+  } {1 aux1 2 aux2 3 aux3}
+}
+
+#-------------------------------------------------------------------------
+#
+reset_db
+forcedelete test.db2
+do_execsql_test 3.0 {
+  CREATE TABLE t1(a PRIMARY KEY, b, c);
+  CREATE VIEW v1 AS SELECT * FROM t1;
+  CREATE TRIGGER v1_ins INSTEAD OF INSERT ON v1 BEGIN
+    INSERT INTO t1 VALUES(new.a, new.b, new.c);
+  END;
+  CREATE TRIGGER v1_del INSTEAD OF DELETE ON v1 BEGIN
+    DELETE FROM t1 WHERE a=old.a;
+  END;
+  CREATE TRIGGER v1_up INSTEAD OF UPDATE ON v1 BEGIN
+    UPDATE t1 SET a=new.a, b=new.b, c=new.c WHERE a=old.a;
+  END;
+}
+forcecopy test.db test.db2
+
+do_test 3.1 {
+  sqlite3 db2 test.db2
+  execsql { INSERT INTO t1 VALUES(1, 2, 3) } db
+  execsql { INSERT INTO t1 VALUES(4, 5, 6) } db2
+  db2 close
+  execsql { ATTACH 'test.db2' AS aux; }
+} {}
+
+do_execsql_test 3.2 {
+  SELECT * FROM main.v1;
+} {1 2 3}
+
+do_execsql_test 3.3 {
+  SELECT * FROM aux.v1;
+} {4 5 6}
+
+db close
+sqlite3 db test.db -shared-schema 1
+
+do_execsql_test 3.4 { ATTACH 'test.db2' AS aux } {}
+do_execsql_test 3.5 { SELECT * FROM main.v1 } {1 2 3}
+do_execsql_test 3.6 { SELECT * FROM aux.v1  } {4 5 6}
+
+do_execsql_test 3.7.1 { INSERT INTO aux.t1 VALUES(8, 9, 10); }
+do_execsql_test 3.7.2 { SELECT * FROM main.v1 } {1 2 3}
+do_execsql_test 3.7.3 { SELECT * FROM aux.v1  } {4 5 6 8 9 10}
+
+do_execsql_test 3.8.1 { DELETE FROM aux.t1 WHERE b=5 }
+do_execsql_test 3.8.2 { SELECT * FROM main.v1 } {1 2 3}
+do_execsql_test 3.8.3 { SELECT * FROM aux.v1  } {8 9 10}
+
+do_execsql_test 3.9.1 { UPDATE aux.t1 SET b='abc' }
+do_execsql_test 3.9.2 { SELECT * FROM main.v1 } {1 2 3}
+do_execsql_test 3.9.3 { SELECT * FROM aux.v1  } {8 abc 10}
+
+do_execsql_test 3.10.1 { INSERT INTO aux.v1 VALUES(11, 12, 13) }
+do_execsql_test 3.10.2 { SELECT * FROM main.v1 } {1 2 3}
+do_execsql_test 3.10.3 { SELECT * FROM aux.v1  } {8 abc 10 11 12 13}
+
+do_execsql_test 3.11.1 { DELETE FROM aux.v1 WHERE b='abc' }
+do_execsql_test 3.11.2 { SELECT * FROM main.v1 } {1 2 3}
+do_execsql_test 3.11.3 { SELECT * FROM aux.v1  } {11 12 13}
+
+do_execsql_test 3.12.1 { UPDATE aux.v1 SET b='def' }
+do_execsql_test 3.12.2 { SELECT * FROM main.v1 } {1 2 3}
+do_execsql_test 3.12.3 { SELECT * FROM aux.v1  } {11 def 13}
+
+do_execsql_test 3.13.1 {
+  CREATE TEMP TRIGGER xyz AFTER INSERT ON aux.t1 BEGIN
+    INSERT INTO v1 VALUES(new.a, new.b, new.c);
+  END
+}
+do_execsql_test 3.13.2 {
+  INSERT INTO aux.v1 VALUES('x', 'y', 'z');
+}
+do_execsql_test 3.13.3 {
+  SELECT * FROM v1;
+} {1 2 3 x y z}
+
+#-------------------------------------------------------------------------
+#
+reset_db
+forcedelete test.db2
+do_execsql_test 4.0 {
+  CREATE TABLE t1(a PRIMARY KEY, b, c UNIQUE);
+  CREATE TABLE del(a, b, c);
+  CREATE TRIGGER tr1 AFTER DELETE ON t1 BEGIN
+    INSERT INTO del VALUES(old.a, old.b, old.c);
+  END;
+}
+forcecopy test.db test.db2
+
+db close
+sqlite3 db test.db -shared-schema 1
+execsql { 
+  ATTACH 'test.db2' AS aux;
+  PRAGMA recursive_triggers = 1;
+}
+
+do_execsql_test 4.1 {
+  INSERT INTO main.t1 VALUES(1, 2, 3);
+  INSERT INTO aux.t1 VALUES(4, 5, 6);
+}
+
+do_execsql_test 4.2.1 {
+  INSERT OR REPLACE INTO aux.t1 VALUES('a', 'b', 6);
+  SELECT * FROM aux.t1;
+} {a b 6}
+do_execsql_test 4.2.2 { SELECT * FROM aux.del  } {4 5 6}
+do_execsql_test 4.2.3 { SELECT * FROM main.del } {}
+
+do_execsql_test 4.3.1 {
+  INSERT INTO aux.t1 VALUES('x', 'y', 'z');
+  UPDATE OR REPLACE aux.t1 SET c='z' WHERE a='a';
+} {}
+do_execsql_test 4.3.2 { SELECT * FROM aux.del  } {4 5 6 x y z}
+do_execsql_test 4.3.3 { SELECT * FROM main.del } {}
+
+#-------------------------------------------------------------------------
+#
+reset_db
+do_execsql_test 5.0 {
+  CREATE TABLE t1(a INTEGER PRIMARY KEY, b, c);
+  CREATE TABLE t2(a INTEGER PRIMARY KEY, b, c);
+  CREATE INDEX i1 ON t1(b);
+  INSERT INTO t1 VALUES(1, 2, 3), (4, 5, 6);
+  ANALYZE;
+  PRAGMA writable_schema = 1;
+  DELETE FROM sqlite_stat1;
+}
+db close
+forcecopy test.db test.db2
+sqlite3 db test.db -shared-schema 1
+execsql { ATTACH 'test.db2' AS aux }
+
+foreach {tn sql} {
+  1 { CREATE TABLE t3(x) }
+  2 { DROP TABLE t2 }
+  3 { CREATE INDEX i2 ON t2(b) }
+  4 { DROP INDEX i1 }
+  5 { ALTER TABLE t1 ADD COLUMN d }
+  6 { ALTER TABLE t1 RENAME TO t3 }
+  7 { ALTER TABLE t1 RENAME c TO d }
+} {
+  do_catchsql_test 5.1.$tn $sql {1 {attempt to modify read-only schema}}
+}
+
+do_execsql_test 5.2.1 { ANALYZE aux.t1 } {}
+do_execsql_test 5.2.2 { SELECT * FROM aux.sqlite_stat1  } {t1 i1 {2 1}}
+do_execsql_test 5.2.3 { SELECT * FROM main.sqlite_stat1 } {}
+
+do_test 5.3.0 {
+  sqlite3 db2 test.db2
+  db2 eval { 
+    PRAGMA writable_schema = 1;
+    DELETE FROM sqlite_stat1;
+  }
+} {}
+
+do_execsql_test 5.3.1 { SELECT * FROM aux.sqlite_stat1  } {}
+do_execsql_test 5.3.2 { ANALYZE aux } {}
+do_execsql_test 5.3.3 { SELECT * FROM aux.sqlite_stat1  } {t1 i1 {2 1}}
+do_execsql_test 5.3.4 { SELECT * FROM main.sqlite_stat1 } {}
+
+#-------------------------------------------------------------------------
+# Attempting to run ANALYZE when the required sqlite_statXX functions
+# are missing is an error (because it would modify the database schema).
+#
+reset_db
+do_execsql_test 5.4 {
+  CREATE TABLE t1(a INTEGER PRIMARY KEY, b, c);
+  CREATE TABLE t2(a INTEGER PRIMARY KEY, b, c);
+  CREATE INDEX i1 ON t1(b);
+  INSERT INTO t1 VALUES(1, 2, 3), (4, 5, 6);
+}
+db close
+sqlite3 db test.db -shared-schema 1
+foreach {tn sql} {
+  1 { ANALYZE }
+  2 { ANALYZE t1 }
+  3 { ANALYZE i1 }
+  4 { ANALYZE main }
+  5 { ANALYZE main.t1 }
+  6 { ANALYZE main.i1 }
+} {
+  do_catchsql_test 5.4.$tn $sql {1 {attempt to modify read-only schema}}
+}
+
+#-------------------------------------------------------------------------
+#
+reset_db
+do_execsql_test 6.0 {
+  CREATE TABLE t1(a INTEGER PRIMARY KEY, b, c);
+  CREATE VIEW v1 AS SELECT * FROM t1;
+}
+db close
+forcecopy test.db test.db2
+sqlite3 db test.db -shared-schema 1
+execsql { ATTACH 'test.db2' AS aux }
+
+do_execsql_test 6.1 {
+  INSERT INTO main.t1(a) VALUES(1), (2), (3);
+  INSERT INTO aux.t1(a) VALUES(4), (5), (6);
+  CREATE TEMP TABLE t2(i,t);
+  INSERT INTO t2 VALUES(2, 'two'), (5, 'five');
+}
+
+do_execsql_test 6.2 {
+  SELECT t FROM t2 WHERE i IN (SELECT a FROM aux.t1)
+} {five}
+do_execsql_test 6.3 {
+  SELECT t FROM t2 WHERE i IN (SELECT a FROM aux.v1)
+} {five}
+
+#-------------------------------------------------------------------------
+#
+reset_db
+do_execsql_test 7.0 {
+  CREATE TABLE p1(a PRIMARY KEY, b);
+  CREATE TABLE p2(a PRIMARY KEY, b);
+  CREATE TABLE c1(x REFERENCES p1 ON UPDATE CASCADE ON DELETE CASCADE);
+}
+
+db close
+forcecopy test.db test.db2
+sqlite3 db test.db -shared-schema 1
+execsql { ATTACH 'test.db2' AS aux }
+
+do_execsql_test 7.1 {
+  INSERT INTO aux.p1 VALUES(1, 'one');
+  INSERT INTO aux.p1 VALUES(2, 'two');
+  PRAGMA foreign_keys = on;
+}
+
+do_execsql_test 7.2 {
+  INSERT INTO aux.c1 VALUES(2);
+}
+
+do_execsql_test 7.3.1 {
+  PRAGMA foreign_keys = off;
+  INSERT INTO main.p2 SELECT * FROM aux.p1;
+}
+do_execsql_test 7.3.2 {
+  SELECT * FROM main.p2;
+} {1 one 2 two}
+
+do_execsql_test 7.3.3 {
+  INSERT INTO aux.p2 VALUES(1, 2);
+}
+
+do_execsql_test 7.3.4 {
+  SELECT main.p2.a FROM main.p2, aux.p2;
+} {1 2}
+
+do_execsql_test 7.3.5 {
+  SELECT * FROM main.p2, aux.p2;
+} {1 one 1 2   2 two 1 2}
+
+do_execsql_test 7.4 {
+  SELECT count(*) FROM aux.p2;
+} {1}
+
+
+finish_test
+
+

test/reuse2.test

@@ -0,0 +1,336 @@
+# 2017 August 9
+#
+# 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.
+#
+#***********************************************************************
+#
+#
+
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+set testprefix reuse2
+
+ifcapable !sharedschema {
+  finish_test
+  return
+}
+
+do_execsql_test 1.0 {
+  CREATE TABLE t1(x INTEGER PRIMARY KEY, y UNIQUE, z);
+  CREATE INDEX i1 ON t1(z);
+  PRAGMA schema_version;
+} {2}
+
+do_test 1.2 {
+  catch { db close }
+  catch { db2 close }
+  sqlite3 db2 test.db -shared-schema 1
+  sqlite3 db  test.db -shared-schema 1
+} {}
+
+do_execsql_test -db db2 1.3.1 {
+  INSERT INTO t1 VALUES(1, 2, 3);
+}
+
+do_execsql_test -db db2 1.3.2 {
+  INSERT INTO t1 VALUES(4, 5, 6);
+}
+
+do_execsql_test 1.3.3 {
+  SELECT * FROM t1;
+} {1 2 3 4 5 6}
+
+#--------------------------------------------------------------------------
+reset_db
+ifcapable fts5 {
+  do_execsql_test 2.0 {
+    CREATE VIRTUAL TABLE ft USING fts5(c);
+    INSERT INTO ft VALUES('one two three');
+  }
+  db close
+  sqlite3 db test.db -shared-schema 1
+
+  do_execsql_test 2.1 {
+    SELECT * FROM ft
+  } {{one two three}}
+}
+
+#--------------------------------------------------------------------------
+reset_db
+do_execsql_test 3.0 {
+  CREATE TABLE t1(x INTEGER PRIMARY KEY, y UNIQUE, z);
+  CREATE INDEX i1 ON t1(z);
+  PRAGMA schema_version;
+} {2}
+
+do_test 3.1 {
+  sqlite3 db1 test.db -shared-schema 1
+  sqlite3 db2 test.db -shared-schema 1
+} {}
+
+do_execsql_test -db db1 3.2.1 { SELECT * FROM t1 }
+do_execsql_test -db db2 3.2.2 { SELECT * FROM t1 }
+
+register_schemapool_module db
+do_execsql_test 3.3 { 
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete
+  FROM schemapool;
+} {nref=2 nschema=1 ndelete=0}
+
+sqlite3 db3 test.db -shared-schema 1
+register_schemapool_module db3
+
+do_execsql_test 3.5 { 
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete
+  FROM schemapool;
+} {nref=2 nschema=1 ndelete=0}
+
+do_execsql_test -db db3 3.6 { 
+  SELECT * FROM t1;
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete
+  FROM schemapool;
+} {nref=3 nschema=1 ndelete=0}
+
+do_execsql_test 3.7 { 
+  CREATE TABLE t2(x);
+}
+
+do_execsql_test 3.8 { 
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete
+  FROM schemapool;
+} {nref=3 nschema=1 ndelete=0}
+
+do_execsql_test -db db1 3.9.1 { SELECT * FROM t1 }
+do_execsql_test 3.9.2 { 
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete
+  FROM schemapool;
+} {nref=1 nschema=1 ndelete=0 nref=2 nschema=1 ndelete=0}
+
+do_execsql_test -db db2 3.10.1 { SELECT * FROM t1 }
+do_execsql_test 3.10.2 { 
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete
+  FROM schemapool ORDER BY 1;
+} {nref=1 nschema=1 ndelete=0 nref=2 nschema=1 ndelete=0}
+
+do_execsql_test -db db3 3.11.1 { SELECT * FROM t1 }
+do_execsql_test 3.11.2 { 
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete
+  FROM schemapool;
+} {nref=3 nschema=1 ndelete=0}
+
+#--------------------------------------------------------------------------
+catch {db1 close}
+catch {db2 close}
+catch {db3 close}
+reset_db
+do_execsql_test 4.0.1 {
+  CREATE TABLE x1(a, b, c);
+  CREATE INDEX x1a ON x1(a);
+  CREATE INDEX x1b ON x1(b);
+}
+do_test 4.0.2 {
+  db close
+  for {set i 1} {$i < 6} {incr i} {
+    forcedelete test.db${i}-journal test.db${i}-wal test.db${i}-wal2 
+    forcecopy test.db test.db${i}
+  }
+  sqlite3 db  test.db
+  sqlite3 db2 test.db -shared-schema 1
+} {}
+
+register_schemapool_module db
+do_execsql_test 4.0.3 {
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete
+  FROM schemapool;
+} {}
+
+do_test 4.1.1 {
+  execsql { 
+    ATTACH 'test.db1' AS db1; 
+    ATTACH 'test.db2' AS db2;
+    ATTACH 'test.db3' AS db3;
+    ATTACH 'test.db4' AS db4;
+    ATTACH 'test.db5' AS db5;
+  } db2
+} {}
+do_execsql_test 4.1.2 {
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete
+  FROM schemapool;
+} {nref=1 nschema=1 ndelete=0}
+do_execsql_test -db db2 4.1.3 {
+  SELECT * FROM db3.x1
+}
+do_execsql_test 4.1.4 {
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete
+  FROM schemapool;
+} {nref=2 nschema=1 ndelete=0}
+do_execsql_test -db db2 4.1.5 {
+  SELECT * FROM db2.x1
+}
+do_execsql_test 4.1.6 {
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete
+  FROM schemapool;
+} {nref=3 nschema=1 ndelete=0}
+do_execsql_test -db db2 4.1.7 {
+  SELECT * FROM x1
+}
+do_execsql_test 4.1.8 {
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete
+  FROM schemapool;
+} {nref=3 nschema=1 ndelete=0}
+
+do_test 4.2.1 {
+  catchsql { SELECT * FROM abc } db2
+} {1 {no such table: abc}}
+do_execsql_test 4.2.2 {
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete
+  FROM schemapool;
+} {nref=6 nschema=1 ndelete=0}
+
+register_schemapool_module db2
+do_execsql_test -db db2 4.3.1 {
+  INSERT INTO x1 VALUES(1, 2, 3);
+  INSERT INTO db1.x1 VALUES(4, 5, 6);
+  INSERT INTO db2.x1 VALUES(7, 8, 9);
+  INSERT INTO db3.x1 VALUES(10, 11, 12);
+  INSERT INTO db4.x1 VALUES(13, 14, 15);
+  INSERT INTO db5.x1 VALUES(16, 17, 18);
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete
+  FROM schemapool;
+} {nref=6 nschema=1 ndelete=0}
+
+do_execsql_test -db db2 4.3.2 {
+  SELECT * FROM db5.x1;
+  SELECT * FROM db4.x1;
+  SELECT * FROM db3.x1;
+  SELECT * FROM db2.x1;
+  SELECT * FROM db1.x1;
+  SELECT * FROM x1;
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete
+  FROM schemapool;
+} {
+  16 17 18  13 14 15  10 11 12  7 8 9  4 5 6  1 2 3
+  nref=6 nschema=1 ndelete=0
+}
+
+do_execsql_test -db db2 4.3.3 {
+  UPDATE x1 SET a=a+10;
+  UPDATE db5.x1 SET a=a+10;
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete
+  FROM schemapool;
+} {
+  nref=6 nschema=1 ndelete=0
+}
+
+do_execsql_test -db db2 4.3.4 {
+  SELECT * FROM db5.x1;
+  SELECT * FROM db4.x1;
+  SELECT * FROM db3.x1;
+  SELECT * FROM db2.x1;
+  SELECT * FROM db1.x1;
+  SELECT * FROM x1;
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete
+  FROM schemapool;
+} {
+  26 17 18  13 14 15  10 11 12  7 8 9  4 5 6  11 2 3
+  nref=6 nschema=1 ndelete=0
+}
+
+do_execsql_test -db db2 4.3.5 {
+  DELETE FROM db3.x1;
+  DELETE FROM x1;
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete
+  FROM schemapool;
+} {
+  nref=6 nschema=1 ndelete=0
+}
+
+do_execsql_test -db db2 4.3.6 {
+  SELECT * FROM db5.x1;
+  SELECT * FROM db4.x1;
+  SELECT * FROM db3.x1;
+  SELECT * FROM db2.x1;
+  SELECT * FROM db1.x1;
+  SELECT * FROM x1;
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete
+  FROM schemapool;
+} {
+  26 17 18  13 14 15  7 8 9  4 5 6 
+  nref=6 nschema=1 ndelete=0
+}
+
+do_execsql_test -db db2 4.3.6 {
+  SELECT * FROM db5.x1, db4.x1, db1.x1;
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete
+  FROM schemapool;
+} {26 17 18 13 14 15 4 5 6 nref=6 nschema=3 ndelete=0}
+
+#--------------------------------------------------------------------------
+# Test the incremental-blob API with REUSE_SCHEMA connections.
+#
+catch {db1 close}
+catch {db2 close}
+catch {db3 close}
+reset_db
+do_execsql_test 5.0.1 {
+  CREATE TABLE bbb(a INTEGER PRIMARY KEY, b);
+}
+db close
+do_test 5.0.2 {
+  sqlite3 db2 test.db -shared-schema 1
+  register_schemapool_module db2
+  for {set i 1} {$i<6} {incr i} {
+    forcedelete test.db${i}-journal test.db${i}-wal test.db${i}-wal2 
+    forcecopy test.db test.db${i}
+    sqlite3 db test.db${i}
+    db eval { INSERT INTO bbb VALUES(123, 'database_' || $i) }
+    db close
+    db2 eval "ATTACH 'test.db${i}' AS db${i}"
+  }
+  execsql {
+    SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete
+      FROM schemapool;
+  } db2
+} {nref=6 nschema=1 ndelete=0}
+
+do_test 5.1.1 {
+  set res [list]
+  for {set i 1} {$i<6} {incr i} {
+    set chan [db2 incrblob db${i} bbb b 123]
+    lappend res [gets $chan]
+    close $chan
+  }
+  set res
+} {database_1 database_2 database_3 database_4 database_5}
+
+do_execsql_test -db db2 5.1.2 {
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete
+  FROM schemapool;
+} {nref=6 nschema=1 ndelete=0}
+
+do_test 5.2.1 {
+  sqlite3_table_column_metadata db2 main bbb a
+} {INTEGER BINARY 0 1 0}
+do_test 5.2.2 {
+  sqlite3_table_column_metadata db2 main bbb b
+} {{} BINARY 0 0 0}
+
+do_execsql_test -db db2 5.2.3 {
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete
+  FROM schemapool;
+} {nref=6 nschema=1 ndelete=0}
+
+do_execsql_test -db db2 5.2.4 {
+  PRAGMA integrity_check;
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete
+  FROM schemapool;
+} {ok nref=6 nschema=1 ndelete=5}
+
+finish_test
+

test/reuse3.test

@@ -0,0 +1,355 @@
+# 2019 February 12
+#
+# 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.
+#
+#***********************************************************************
+#
+#
+
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+set testprefix reuse3
+
+ifcapable !sharedschema {
+  finish_test
+  return
+}
+
+do_execsql_test 1.0 {
+  CREATE TABLE t1(x INTEGER PRIMARY KEY, y UNIQUE, z);
+  CREATE INDEX i1 ON t1(z);
+  CREATE TABLE t2(a);
+} {}
+
+db close
+sqlite3 db test.db -shared-schema 1
+
+do_execsql_test 1.1 {
+  CREATE TEMP VIEW v1 AS SELECT * FROM t1;
+  SELECT * FROM v1;
+}
+
+do_execsql_test 1.2 {
+  CREATE TEMP TRIGGER tr1 AFTER INSERT ON t1 BEGIN
+    INSERT INTO t2 VALUES(new.x);
+  END;
+}
+
+do_execsql_test 1.3 {
+  INSERT INTO t1 VALUES(1, 2, 3);
+}
+
+do_execsql_test 1.4 {
+  SELECT * FROM t2
+} {1}
+
+do_execsql_test 1.5 {
+  SELECT * FROM v1
+} {1 2 3}
+
+do_execsql_test 1.6 {
+  BEGIN;
+    DROP TRIGGER tr1;
+  ROLLBACK;
+}
+
+do_execsql_test 1.7 {
+  SELECT * FROM v1
+} {1 2 3}
+
+do_execsql_test 1.8 {
+  INSERT INTO t1 VALUES(4, 5, 6);
+  SELECT * FROM t2
+} {1 4}
+
+do_execsql_test 1.9 {
+  SELECT * FROM v1
+} {1 2 3 4 5 6}
+
+#-------------------------------------------------------------------------
+# Test error messages when parsing the schema with a REUSE_SCHEMA 
+# connection.
+reset_db
+do_execsql_test 2.0 {
+  CREATE TABLE x1(a, b, c);
+  CREATE TABLE y1(d, e, f);
+  PRAGMA writable_schema = 1;
+  UPDATE sqlite_master SET sql = 'CREATE TBL y1(d, e, f)' WHERE name = 'y1';
+}
+db close
+
+sqlite3 db test.db -shared-schema 1
+do_catchsql_test 2.1 {
+  SELECT * FROM x1;
+} {1 {malformed database schema (y1) - near "TBL": syntax error}}
+
+do_catchsql_test 2.2 {
+  SELECT * FROM x1;
+} {1 {malformed database schema (y1) - near "TBL": syntax error}}
+
+#-------------------------------------------------------------------------
+reset_db
+do_execsql_test 3.0 {
+  CREATE TABLE x1(a, b, c);
+  CREATE INDEX i1 ON x1(a, b, c);
+  CREATE TRIGGER tr1 AFTER INSERT ON x1 BEGIN
+    SELECT 1, 2, 3, 4, 5;
+  END;
+  INSERT INTO x1 VALUES(1, 2, 3);
+}
+sqlite3 db1 test.db -shared-schema 1
+
+do_test 3.1 {
+  execsql { SELECT * FROM x1 } db1
+  set N [lindex [sqlite3_db_status db1 SCHEMA_USED 0] 1]
+  expr $N==$N
+} 1
+
+sqlite3 db2 test.db -shared-schema 1
+do_test 3.2 {
+  execsql { SELECT * FROM x1 } db2
+  set N2 [lindex [sqlite3_db_status db2 SCHEMA_USED 0] 1]
+  expr $N2>($N/2) && $N2<($N/2)+400
+} 1
+
+sqlite3 db3 test.db -shared-schema 1
+sqlite3 db4 test.db -shared-schema 1
+do_test 3.3 {
+  execsql { SELECT * FROM x1 } db3
+  execsql { SELECT * FROM x1 } db4
+  set N4 [lindex [sqlite3_db_status db2 SCHEMA_USED 0] 1]
+  set M [expr 2*($N-$N2)]
+  set {} {}
+} {}
+do_test 3.3.1 { expr {(($M / 4) + $N-$M)} } "#/$N4/"
+
+catch { db1 close }
+catch { db2 close }
+catch { db3 close }
+catch { db4 close }
+
+#-------------------------------------------------------------------------
+# 4.1 Test the REINDEX command.
+# 4.2 Test CREATE TEMP ... commands.
+#
+reset_db
+do_execsql_test 4.1.0 {
+  CREATE TABLE x1(a, b, c);
+  CREATE INDEX x1a ON x1(a);
+  CREATE INDEX x1b ON x1(b);
+  CREATE INDEX x1c ON x1(c);
+}
+db close
+sqlite3 db test.db -shared-schema 1
+
+do_execsql_test 4.1.1 {
+  REINDEX x1;
+  REINDEX x1a;
+  REINDEX x1b;
+  REINDEX x1c;
+  REINDEX;
+}
+
+do_test 4.1.2 {
+  for {set i 1} {$i < 5} {incr i} {
+    forcedelete test.db${i} test.db${i}-wal test.db${i}-journal
+    forcecopy test.db test.db${i}
+    execsql "ATTACH 'test.db${i}' AS db${i}"
+  }
+  register_schemapool_module db
+  set {} {}
+  execsql { 
+    SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete 
+    FROM schemapool 
+  }
+} {nref=5 nschema=1 ndelete=0}
+
+do_execsql_test 4.1.3 {
+  REINDEX  x1;
+  REINDEX  x1a;
+  REINDEX  x1b;
+  REINDEX  x1c;
+  REINDEX  db1.x1a;
+  REINDEX  db2.x1b;
+  REINDEX  db3.x1c;
+}
+
+do_execsql_test 4.1.4 {
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete 
+    FROM schemapool 
+} {nref=5 nschema=1 ndelete=28}
+
+#-------------------------------------------------------------------------
+db close
+sqlite3 db test.db -shared-schema 1
+register_schemapool_module db
+do_execsql_test 4.2.0 {
+  ATTACH 'test.db1' AS db1;
+  ATTACH 'test.db2' AS db2;
+  ATTACH 'test.db3' AS db3;
+  ATTACH 'test.db4' AS db4;
+
+  SELECT * FROM db1.x1;
+  SELECT * FROM db2.x1;
+  SELECT * FROM db3.x1;
+  SELECT * FROM db4.x1;
+}
+
+do_execsql_test 4.2.1 {
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete 
+    FROM schemapool; 
+} {nref=5 nschema=1 ndelete=0}
+
+do_execsql_test 4.2.2 {
+  CREATE TEMP TABLE t1(a, b, c);
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete 
+    FROM schemapool; 
+} {nref=5 nschema=1 ndelete=0}
+
+do_execsql_test 4.2.3 {
+  CREATE INDEX t1a ON t1(a);
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete 
+    FROM schemapool; 
+} {nref=5 nschema=1 ndelete=0}
+
+do_execsql_test 4.2.4 {
+  CREATE TRIGGER tr1 AFTER INSERT ON t1 BEGIN
+    SELECT 1,2,3,4;
+  END;
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete 
+    FROM schemapool; 
+} {nref=5 nschema=1 ndelete=0}
+
+do_execsql_test 4.2.5 {
+  DROP TABLE t1;
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete 
+    FROM schemapool; 
+} {nref=5 nschema=1 ndelete=0}
+
+do_execsql_test 4.2.6 {
+  CREATE TEMP TRIGGER tr1 AFTER INSERT ON db2.x1 BEGIN
+    SELECT 1,2,3,4;
+  END;
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete 
+    FROM schemapool; 
+} {nref=5 nschema=1 ndelete=0}
+
+do_execsql_test 4.2.7 {
+  DROP TRIGGER tr1;
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema, 'ndelete=' || nDelete 
+    FROM schemapool; 
+} {nref=5 nschema=1 ndelete=4}
+
+#--------------------------------------------------------------------------
+reset_db
+do_execsql_test 5.0 {
+  CREATE TABLE t1(a, b);
+  CREATE TABLE t2(a, b);
+  CREATE TABLE t3(a, b);
+}
+
+sqlite3 db2 test.db -shared-schema 1
+register_schemapool_module db2
+
+do_execsql_test 5.1 {
+  PRAGMA writable_schema = 1;
+  UPDATE sqlite_master SET sql='CREATE TABLE t3 a,b' WHERE name = 't3';
+}
+
+do_test 5.2 { 
+  catchsql { SELECT * FROM t1 } db2
+} {1 {malformed database schema (t3) - near "a": syntax error}}
+
+do_test 5.3 { 
+  catchsql { SELECT nref,nschema FROM schemapool } db2
+} {1 {malformed database schema (t3) - near "a": syntax error}}
+
+do_execsql_test 5.4 {
+  PRAGMA writable_schema = 1;
+  UPDATE sqlite_master SET sql='CREATE TABLE t3(a,b)' WHERE name = 't3';
+}
+
+do_test 5.5 { 
+  catchsql { SELECT nref,nschema FROM schemapool } db2
+} {0 {1 1}}
+
+db2 close
+db close
+do_test 5.6.1 {
+  forcedelete test.db2 test.db2-wal test.db2-journal
+  forcecopy test.db test.db2
+  sqlite3 db test.db
+  sqlite3 db2 test.db  -shared-schema 1
+  sqlite3 db3 test.db2 -shared-schema 1
+  register_schemapool_module db
+} {}
+
+do_execsql_test -db db2 5.6.2 { SELECT * FROM t1 }
+do_execsql_test -db db3 5.6.3 { SELECT * FROM t1 }
+do_execsql_test 5.6.4 {
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema FROM schemapool; 
+  CREATE TABLE t4(x);
+  DROP TABLE t4;
+} {nref=2 nschema=1}
+do_execsql_test -db db2 5.6.5 { SELECT * FROM t1 }
+do_execsql_test -db db3 5.6.6 { SELECT * FROM t1 }
+do_execsql_test 5.6.7 {
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema FROM schemapool; 
+  ATTACH 'test.db2' AS db2;
+  CREATE TABLE db2.t4(x);
+  DROP TABLE db2.t4;
+} {nref=1 nschema=1 nref=1 nschema=1}
+do_execsql_test -db db2 5.6.8 { SELECT * FROM t1 }
+do_execsql_test -db db3 5.6.9 { SELECT * FROM t1 }
+do_execsql_test 5.6.10 {
+  SELECT 'nref=' || nRef, 'nschema=' || nSchema FROM schemapool; 
+} {nref=2 nschema=1}
+
+#-------------------------------------------------------------------------
+reset_db
+do_execsql_test 6.0 {
+  CREATE TABLE t1(a, b);
+  CREATE TABLE t2(a, b);
+  CREATE TABLE t3(a, b);
+}
+
+do_test 6.1 {
+  db close
+  sqlite3 db test.db -shared-schema 1
+  for {set i 1} {$i < 5} {incr i} {
+    set base "test.db$i"
+    set nm "aux$i"
+    forcedelete $base $base-wal $base-journal
+    forcecopy test.db $base
+    execsql "ATTACH '$base' AS $nm"
+  }
+} {}
+
+do_test 6.2 {
+  set N1 [lindex [sqlite3_db_status db SCHEMA_USED 0] 1]
+  set N2 [lindex [sqlite3_db_status db SCHEMA_USED 0] 1]
+  expr {$N1>0 && $N2>0 && $N1==$N2}
+} {1}
+
+do_test 6.3 {
+  execsql { SELECT * FROM main.t1 }
+  set N1 [lindex [sqlite3_db_status db SCHEMA_USED 0] 1]
+  set N2 [lindex [sqlite3_db_status db SCHEMA_USED 0] 1]
+  expr {$N1>0 && $N2>0 && $N1==$N2}
+} {1}
+
+do_test 6.4 {
+  execsql { SELECT * FROM aux1.t1 }
+  set N3 [lindex [sqlite3_db_status db SCHEMA_USED 0] 1]
+  set N4 [lindex [sqlite3_db_status db SCHEMA_USED 0] 1]
+  list $N3 $N4
+} "#/$N1 $N1/"
+
+finish_test
+

test/reuse4.test

@@ -0,0 +1,173 @@
+# 2019 February 12
+#
+# 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.
+#
+#***********************************************************************
+#
+#
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+set testprefix reuse4
+
+ifcapable !sharedschema {
+  finish_test
+  return
+}
+
+foreach {tn sharedschema} {
+  1 0  
+  2 1  
+} {
+  reset_db
+
+  do_execsql_test 1.$tn.0 {
+    CREATE TABLE x1(a, b);
+    CREATE INDEX x1a ON x1(a);
+    CREATE INDEX x1b ON x1(b);
+    CREATE TABLE x2(a, b);
+  }
+  db close
+  
+  do_test 1.$tn.1 {
+    for {set i 1} {$i<4} {incr i} {
+      forcedelete test.db$i test.db$i-journal test.db$i-wal
+      forcecopy test.db test.db$i
+    }
+  
+    sqlite3 db test.db -shared-schema $sharedschema
+    for {set i 1} {$i<4} {incr i} {
+      execsql " ATTACH 'test.db$i' AS db$i "
+    }
+  } {}
+  
+  do_execsql_test 1.$tn.2 {
+    WITH s(i) AS ( SELECT 1 UNION ALL SELECT i+1 FROM s WHERE i<10 )
+    INSERT INTO x1 SELECT i, i FROM s;
+  
+    INSERT INTO db3.x2 SELECT * FROM x1;
+    INSERT INTO db2.x1 SELECT * FROM db3.x2;
+    CREATE TEMP TRIGGER tr1 AFTER INSERT ON db2.x2 BEGIN
+      INSERT INTO x1 VALUES(new.a, new.b);
+    END;
+    INSERT INTO db2.x2 SELECT * FROM x1 WHERE a%2;
+    DELETE FROM x1 WHERE a<3;
+    INSERT INTO db3.x1 SELECT * FROM db2.x2;
+  
+    DETACH db3;
+    ATTACH 'test.db3' AS db3;
+  
+    UPDATE db3.x1 SET a=a-10 WHERE b NOT IN (SELECT b FROM db2.x2);
+  
+    CREATE TEMP TABLE x1(a, b);
+    INSERT INTO db2.x2 VALUES(50, 60), (60, 70), (80, 90);
+    ALTER TABLE x1 RENAME TO x2;
+    ALTER TABLE x2 ADD COLUMN c;
+    ALTER TABLE x2 RENAME a TO aaa;
+    DELETE FROM x1 WHERE b>8;
+    UPDATE db3.x2 SET b=b*10;
+  
+    BEGIN;
+      CREATE TEMP TABLE x5(x);
+      INSERT INTO x5 VALUES(1);
+    ROLLBACK;
+  
+    INSERT INTO main.x2 VALUES(123, 456);
+  }
+  
+  integrity_check 1.$tn.3
+  
+  do_execsql_test 1.$tn.4 {
+    SELECT * FROM main.x1; SELECT 'xxx';
+    SELECT * FROM main.x2; SELECT 'xxx';
+    SELECT * FROM temp.x2; SELECT 'xxx';
+  
+    SELECT * FROM db1.x1; SELECT 'xxx';
+    SELECT * FROM db1.x2; SELECT 'xxx';
+    SELECT * FROM db2.x1; SELECT 'xxx';
+    SELECT * FROM db2.x2; SELECT 'xxx';
+    SELECT * FROM db3.x1; SELECT 'xxx';
+    SELECT * FROM db3.x2; SELECT 'xxx';
+  } {
+    3 3 4 4 5 5 6 6 7 7 8 8 3 3 5 5 7 7 xxx 
+    123 456 xxx 
+    50 60 {} 60 70 {} 80 90 {} xxx
+    xxx
+    xxx
+    1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 9 9 10 10 xxx
+    1 1 3 3 5 5 7 7 9 9 50 60 60 70 80 90 xxx
+    1 1 3 3  5 5 7 7 9 9 xxx 
+    1 10 2 20 3 30 4 40 5 50 6 60 7 70 8 80 9 90 10 100 xxx
+  }
+  
+  do_test 1.$tn.5.1 {
+    sqlite3 db2 test.db
+    db2 eval { CREATE TABLE x3(x) }
+  } {}
+  do_execsql_test 1.$tn.5.2 {
+    SELECT * FROM main.x1; SELECT 'xxx';
+    SELECT * FROM main.x2; SELECT 'xxx';
+    SELECT * FROM main.x3; SELECT 'xxx';
+  } {
+    3 3 4 4 5 5 6 6 7 7 8 8 3 3 5 5 7 7 xxx 
+    123 456 xxx 
+    xxx
+  }
+}
+
+#-------------------------------------------------------------------------
+# Test some PRAGMA statements with shared-schema connections.
+#
+reset_db
+do_execsql_test 2.0 {
+  CREATE TABLE t1(a, b, c);
+  CREATE INDEX t1abc ON t1(a, b, c);
+}
+
+foreach {tn pragma nSchema nDelete} {
+  1 "PRAGMA synchronous = OFF"     1 0
+  2 "PRAGMA cache_size = 200"      1 0
+  3 "PRAGMA aux2.integrity_check"  1 0
+  4 "PRAGMA      integrity_check"  1 5
+  5 "PRAGMA index_info=t1abc"      1 5
+  6 "PRAGMA aux3.index_info=t1abc" 1 0
+  7 "PRAGMA journal_mode"          1 0
+  8 "PRAGMA aux2.wal_checkpoint"   1 0
+  9 "PRAGMA wal_checkpoint"        1 0
+} {
+  do_test 2.$tn.1 {
+    catch { db close }
+    catch { db2 close }
+    for {set i 1} {$i < 6} {incr i} {
+      forcedelete "test.db$i" "test.db${i}-wal" "test.db${i}-journal"
+      forcecopy test.db test.db$i
+    }
+    sqlite3 db2 test.db -shared-schema 1
+    for {set i 1} {$i < 6} {incr i} {
+      execsql "ATTACH 'test.db$i' AS aux$i" db2
+    }
+  } {}
+
+  sqlite3 db test.db
+  register_schemapool_module db
+
+  do_test 2.$tn.2 {
+    execsql $pragma db2
+    execsql { SELECT 'nschema='||nschema, 'ndelete='||nDelete FROM schemapool }
+  } "nschema=$nSchema ndelete=$nDelete"
+
+  do_test 2.$tn.3 {
+    execsql {
+      SELECT * FROM main.t1,aux1.t1,aux2.t1,aux3.t1,aux4.t1,aux5.t1
+    } db2
+    execsql { SELECT 'nschema=' || nschema, 'nref=' || nref FROM schemapool }
+  } "nschema=6 nref=6"
+}
+
+finish_test
+

test/reuse5.test

@@ -0,0 +1,125 @@
+# 2019 February 26
+#
+# 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.
+#
+#***********************************************************************
+#
+#
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+set testprefix reuse5
+set CLI [test_find_cli]
+
+ifcapable !sharedschema {
+  finish_test
+  return
+}
+
+do_execsql_test 1.0 {
+  CREATE TABLE t1(x, y);
+  CREATE TABLE t2(a, b, c);
+  CREATE INDEX t1x ON t1(x);
+  CREATE INDEX t1y ON t1(y);
+  CREATE VIEW v1 AS SELECT * FROM t2;
+}
+
+foreach {tn sql out1 out2} {
+  1 {
+    CREATE TABLE t1(x, y);
+    CREATE TABLE t2(a, b, c);
+    CREATE INDEX t1x ON t1(x);
+    CREATE INDEX t1y ON t1(y);
+    CREATE VIEW v1 AS SELECT * FROM t2;
+  } {
+    test.db2 is compatible
+  } {}
+
+  2 {
+    CREATE TABLE t1(x, y);
+    CREATE TABLE t2(a, b, c);
+    CREATE INDEX t1x ON t1(x);
+    CREATE INDEX t1y ON t1(y);
+    CREATE VIEW v1 AS SELECT * FROM t2;
+    CREATE TABLE x1(x);
+    DROP TABLE x1;
+  } {
+    test.db2 is NOT compatible (schema cookie)
+  } {
+    Fixing test.db2... test.db2 is compatible
+  }
+
+  3 {
+    CREATE TABLE t1(x, y);
+    CREATE TABLE t2(a, b, c);
+    CREATE INDEX t1y ON t1(y);
+    CREATE VIEW v1 AS SELECT * FROM t2;
+  } {
+    test.db2 is NOT compatible (objects)
+  } {}
+
+  4 {
+    CREATE TABLE t1(x, y);
+    CREATE TABLE t2(a, b, c);
+    CREATE INDEX t1x ON t1(X);
+    CREATE INDEX t1y ON t1(y);
+    CREATE VIEW v1 AS SELECT * FROM t2;
+  } {
+    test.db2 is NOT compatible (SQL)
+  } {}
+
+  5 {
+    CREATE TABLE t1(x, y);
+    CREATE TABLE t2(a, b, c);
+    CREATE INDEX t1y ON t1(y);
+    CREATE INDEX t1x ON t1(x);
+    CREATE VIEW v1 AS SELECT * FROM t2;
+  } {
+    test.db2 is NOT compatible (root pages)
+  } {
+    Fixing test.db2... test.db2 is compatible
+  }
+
+  6 {
+    CREATE TABLE t1(x, y);
+    CREATE TABLE t2(a, b, c);
+    CREATE INDEX t1x ON t1(x);
+    CREATE INDEX t1y ON t1(y);
+    CREATE VIEW v1 AS SELECT * FROM t2;
+    DROP INDEX t1x;
+    CREATE INDEX t1x ON t1(x);
+  } {
+    test.db2 is NOT compatible (order of sqlite_master rows)
+  } {
+    Fixing test.db2... test.db2 is compatible
+  }
+
+} {
+  forcedelete test.db2
+  sqlite3 db2 test.db2
+  db2 eval $sql
+  db2 close
+
+  if {$out2==""} {set out2 $out1}
+
+  do_test 1.$tn.1 {
+    catchcmd test.db ".shared-schema check test.db2"
+  } [list 0 [string trim $out1]]
+
+  do_test 1.$tn.2 {
+    catchcmd test.db ".shared-schema fix test.db2"
+  } [list 0 [string trim $out2]]
+
+  do_test 1.$tn.3 {
+    catchcmd test.db2 "PRAGMA integrity_check"
+  } [list 0 ok]
+}
+
+
+finish_test
+

test/reuse6.test

@@ -0,0 +1,143 @@
+# 2019 February 26
+#
+# 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.
+#
+#***********************************************************************
+#
+#
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+set testprefix reuse6
+
+ifcapable !sharedschema {
+  finish_test
+  return
+}
+
+do_execsql_test 1.0 {
+  CREATE TABLE t1(x, y);
+  CREATE TABLE t2(a, b, c);
+  CREATE INDEX t1x ON t1(x);
+  CREATE INDEX t1y ON t1(y);
+  CREATE VIEW v1 AS SELECT * FROM t2;
+
+  INSERT INTO t1 VALUES(1, 2), (3, 4), (5, 6);
+  INSERT INTO t2 VALUES('a', 'b', 'c'), ('d', 'e', 'f'), ('g', 'h', 'i');
+
+  ATTACH 'test.db2' AS aux;
+  CREATE TABLE t3(i, ii);
+  INSERT INTO t3 VALUES(10, 20);
+}
+
+sqlite3 db1 test.db -shared-schema 1
+sqlite3 db2 test.db -shared-schema 1
+
+do_execsql_test -db db1 1.1 {
+  ATTACH 'test.db2' AS aux;
+}
+
+do_test 1.2 {
+  execsql {SELECT * FROM t3} db1
+} {10 20}
+
+do_execsql_test -db db2 1.3 {
+  ATTACH 'test.db2' AS aux;
+}
+
+do_test 1.3 {
+  execsql {SELECT * FROM t3} db1
+} {10 20}
+
+do_execsql_test -db db2 1.5 {
+  SELECT * FROM t3;
+} {10 20}
+
+do_test 1.6 {
+  execsql {SELECT * FROM t3} db1
+} {10 20}
+
+db1 close
+db2 close
+
+#-------------------------------------------------------------------------
+reset_db
+forcedelete test.db2
+forcedelete test.db3
+do_execsql_test 2.0 {
+  CREATE TABLE t1(x, y);
+  ATTACH 'test.db2' AS aux2;
+  CREATE TABLE aux2.t2(x, y);
+  ATTACH 'test.db3' AS aux3;
+  CREATE TABLE aux3.t3(x, y);
+}
+
+sqlite3 db1 test.db -shared-schema 1
+do_execsql_test -db db1 2.1 {
+  ATTACH 'test.db2' AS aux2;
+  ATTACH 'test.db3' AS aux3;
+}
+
+do_test 2.2.1 {
+  catchsql { SELECT * FROM aux2.nosuchtable } db1
+} {1 {no such table: aux2.nosuchtable}}
+do_test 2.2.2 {
+  sqlite3_errcode db1
+} {SQLITE_ERROR}
+db1 close
+
+#-------------------------------------------------------------------------
+reset_db
+forcedelete test.db2
+ifcapable fts5 {
+  do_execsql_test 3.0 {
+    CREATE VIRTUAL TABLE ft USING fts5(a, b);
+    ATTACH 'test.db2' AS aux;
+    CREATE TABLE aux.t1(x, y, z);
+  }
+
+  sqlite3 db1 test.db -shared-schema 1
+  do_execsql_test -db db1 3.1 {
+    ATTACH 'test.db2' AS aux;
+  }
+
+  do_execsql_test -db db1 3.2 {
+    SELECT * FROM main.ft, aux.t1;
+  }
+  db1 close
+}
+
+#-------------------------------------------------------------------------
+reset_db
+forcedelete test.db2
+ifcapable fts5 {
+  do_execsql_test 4.0 {
+    CREATE VIRTUAL TABLE ft USING fts5(a, b);
+  }
+  forcecopy test.db test.db2
+
+  sqlite3 db1 test.db -shared-schema 1
+  do_execsql_test -db db1 4.1 {
+    ATTACH 'test.db2' AS aux;
+    SELECT * FROM main.ft;
+    SELECT * FROM aux.ft;
+  }
+
+  do_execsql_test -db db1 4.2 {
+    SELECT * FROM main.ft, aux.ft
+  }
+}
+
+
+
+
+
+
+
+finish_test
+

test/reusefault.test

@@ -0,0 +1,54 @@
+# 2019 February 12
+#
+# 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.
+#
+#***********************************************************************
+#
+#
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+set testprefix reusefault
+
+ifcapable !sharedschema {
+  finish_test
+  return
+}
+
+do_execsql_test 1.0 {
+  PRAGMA cache_size = 10;
+  CREATE TABLE t1(a UNIQUE, b UNIQUE);
+  INSERT INTO t1 VALUES(1, 2), (3, 4);
+}
+faultsim_save_and_close
+
+do_faultsim_test 1.1 -prep {
+  faultsim_restore
+  sqlite3 db test.db -shared-schema 1
+} -body {
+  execsql { SELECT * FROM t1 }
+} -test {
+  faultsim_test_result {0 {1 2 3 4}}
+}
+
+do_faultsim_test 1.2 -prep {
+  faultsim_restore
+  sqlite3 db test.db -shared-schema 1
+  execsql { SELECT * FROM t1 }
+  sqlite3 db2 test.db
+  db2 eval {CREATE TABLE a(a)}
+  db2 close
+} -body {
+  execsql { SELECT  * FROM t1 }
+} -test {
+  faultsim_test_result {0 {1 2 3 4}}
+}
+
+
+finish_test
+

test/shell1.test

@@ -496,11 +496,16 @@ do_test shell1-3.14.3 {
 
 # .output FILENAME       Send output to FILENAME
 do_test shell1-3.15.1 {
-  catchcmd "test.db" ".output"
-} {0 {}}
+  catchcmd "test.db" ".output
+.print x"
+} {0 x}
 do_test shell1-3.15.2 {
-  catchcmd "test.db" ".output FOO"
-} {0 {}}
+  catchcmd "test.db" ".output FOO
+.print x
+.output
+SELECT readfile('FOO');"
+} {0 {x
+}}
 do_test shell1-3.15.3 {
   # too many arguments
   catchcmd "test.db" ".output FOO BAD"
@@ -1067,7 +1072,7 @@ do_test shell1-5.0 {
       #
       set escapes [list \
           \a \\a \b \\b \t \\t \n \\n \v \\v \f \\f \r \\r \
-          " " "\" \"" \" \\\" ' \"'\" \\ \\\\]
+          " " "\" \"" \" \\\" \\ \\\\]
     } else {
       #
       # NOTE: On Unix, we need to escape most of the whitespace characters

test/tclsqlite.test

@@ -26,6 +26,9 @@ set testprefix tcl
 # Check the error messages generated by tclsqlite
 #
 set r "sqlite_orig HANDLE ?FILENAME? ?-vfs VFSNAME? ?-readonly BOOLEAN? ?-create BOOLEAN? ?-nofollow BOOLEAN? ?-nomutex BOOLEAN? ?-fullmutex BOOLEAN? ?-uri BOOLEAN?"
+ifcapable sharedschema {
+  append r " ?-shared-schema BOOLEAN?"
+}
 if {[sqlite3 -has-codec]} {
   append r " ?-key CODECKEY?"
 }

test/tester.tcl

@@ -880,7 +880,7 @@ proc catchcmd {db {cmd ""}} {
   set out [open cmds.txt w]
   puts $out $cmd
   close $out
-  set line "exec $CLI $db < cmds.txt"
+  set line "exec $CLI --unsafe-testing $db < cmds.txt"
   set rc [catch { eval $line } msg]
   list $rc $msg
 }

test/threadtest3.c

@@ -38,7 +38,7 @@
 #define SEL(e) ((e)->iLine = ((e)->rc ? (e)->iLine : __LINE__))
 
 /* Database functions */
-#define opendb(w,x,y,z)         (SEL(w), opendb_x(w,x,y,z))
+#define opendb(w,x,y,z,f)       (SEL(w), opendb_x(w,x,y,z,f))
 #define closedb(y,z)            (SEL(y), closedb_x(y,z))
 
 /* Functions to execute SQL */
@@ -545,11 +545,14 @@ static void opendb_x(
   Error *pErr,                    /* IN/OUT: Error code */
   Sqlite *pDb,                    /* OUT: Database handle */
   const char *zFile,              /* Database file name */
-  int bDelete                     /* True to delete db file before opening */
+  int bDelete,                    /* True to delete db file before opening */
+  int flags
 ){
   if( pErr->rc==SQLITE_OK ){
     int rc;
-    int flags = SQLITE_OPEN_CREATE | SQLITE_OPEN_READWRITE | SQLITE_OPEN_URI;
+    if( flags==0 ){
+      flags = SQLITE_OPEN_CREATE | SQLITE_OPEN_READWRITE | SQLITE_OPEN_URI;
+    }
     if( bDelete ) unlink(zFile);
     rc = sqlite3_open_v2(zFile, &pDb->db, flags, 0);
     if( rc ){
@@ -985,7 +988,7 @@ static char *walthread1_thread(int iTid, void *pArg){
   Sqlite db = {0};                /* SQLite database connection */
   int nIter = 0;                  /* Iterations so far */
 
-  opendb(&err, &db, "test.db", 0);
+  opendb(&err, &db, "test.db", 0, 0);
   while( !timetostop(&err) ){
     const char *azSql[] = {
       "SELECT md5sum(x) FROM t1 WHERE rowid != (SELECT max(rowid) FROM t1)",
@@ -1024,7 +1027,7 @@ static char *walthread1_ckpt_thread(int iTid, void *pArg){
   Sqlite db = {0};                /* SQLite database connection */
   int nCkpt = 0;                  /* Checkpoints so far */
 
-  opendb(&err, &db, "test.db", 0);
+  opendb(&err, &db, "test.db", 0, 0);
   while( !timetostop(&err) ){
     sqlite3_sleep(500);
     execsql(&err, &db, "PRAGMA wal_checkpoint");
@@ -1043,7 +1046,7 @@ static void walthread1(int nMs){
   Threadset threads = {0};        /* Test threads */
   int i;                          /* Iterator variable */
 
-  opendb(&err, &db, "test.db", 1);
+  opendb(&err, &db, "test.db", 1, 0);
   sql_script(&err, &db,
       "PRAGMA journal_mode = WAL;"
       "CREATE TABLE t1(x PRIMARY KEY);"
@@ -1076,7 +1079,7 @@ static char *walthread2_thread(int iTid, void *pArg){
     int journal_exists = 0;
     int wal_exists = 0;
 
-    opendb(&err, &db, "test.db", 0);
+    opendb(&err, &db, "test.db", 0, 0);
 
     sql_script(&err, &db, zJournal);
     clear_error(&err, SQLITE_BUSY);
@@ -1106,7 +1109,7 @@ static void walthread2(int nMs){
   Sqlite db = {0};
   Threadset threads = {0};
 
-  opendb(&err, &db, "test.db", 1);
+  opendb(&err, &db, "test.db", 1, 0);
   sql_script(&err, &db, "CREATE TABLE t1(x INTEGER PRIMARY KEY, y UNIQUE)");
   closedb(&err, &db);
 
@@ -1126,7 +1129,7 @@ static char *walthread3_thread(int iTid, void *pArg){
   i64 iNextWrite;                 /* Next value this thread will write */
   int iArg = PTR2INT(pArg);
 
-  opendb(&err, &db, "test.db", 0);
+  opendb(&err, &db, "test.db", 0, 0);
   sql_script(&err, &db, "PRAGMA wal_autocheckpoint = 10");
 
   iNextWrite = iArg+1;
@@ -1163,7 +1166,7 @@ static void walthread3(int nMs){
   Threadset threads = {0};
   int i;
 
-  opendb(&err, &db, "test.db", 1);
+  opendb(&err, &db, "test.db", 1, 0);
   sql_script(&err, &db, 
       "PRAGMA journal_mode = WAL;"
       "CREATE TABLE t1(cnt PRIMARY KEY, sum1, sum2);"
@@ -1186,7 +1189,7 @@ static char *walthread4_reader_thread(int iTid, void *pArg){
   Error err = {0};                /* Error code and message */
   Sqlite db = {0};                /* SQLite database connection */
 
-  opendb(&err, &db, "test.db", 0);
+  opendb(&err, &db, "test.db", 0, 0);
   while( !timetostop(&err) ){
     integrity_check(&err, &db);
   }
@@ -1201,7 +1204,7 @@ static char *walthread4_writer_thread(int iTid, void *pArg){
   Sqlite db = {0};                /* SQLite database connection */
   i64 iRow = 1;
 
-  opendb(&err, &db, "test.db", 0);
+  opendb(&err, &db, "test.db", 0, 0);
   sql_script(&err, &db, "PRAGMA wal_autocheckpoint = 15;");
   while( !timetostop(&err) ){
     execsql_i64(
@@ -1221,7 +1224,7 @@ static void walthread4(int nMs){
   Sqlite db = {0};
   Threadset threads = {0};
 
-  opendb(&err, &db, "test.db", 1);
+  opendb(&err, &db, "test.db", 1, 0);
   sql_script(&err, &db, 
       "PRAGMA journal_mode = WAL;"
       "CREATE TABLE t1(a INTEGER PRIMARY KEY, b UNIQUE);"
@@ -1241,7 +1244,7 @@ static char *walthread5_thread(int iTid, void *pArg){
   Sqlite db = {0};                /* SQLite database connection */
   i64 nRow;
 
-  opendb(&err, &db, "test.db", 0);
+  opendb(&err, &db, "test.db", 0, 0);
   nRow = execsql_i64(&err, &db, "SELECT count(*) FROM t1");
   closedb(&err, &db);
 
@@ -1254,7 +1257,7 @@ static void walthread5(int nMs){
   Sqlite db = {0};
   Threadset threads = {0};
 
-  opendb(&err, &db, "test.db", 1);
+  opendb(&err, &db, "test.db", 1, 0);
   sql_script(&err, &db, 
       "PRAGMA wal_autocheckpoint = 0;"
       "PRAGMA page_size = 1024;"
@@ -1345,7 +1348,7 @@ static void cgt_pager_1(int nMs){
   Error err = {0};
   Sqlite db = {0};
 
-  opendb(&err, &db, "test.db", 1);
+  opendb(&err, &db, "test.db", 1, 0);
   sql_script(&err, &db,
       "PRAGMA cache_size = 2000;"
       "PRAGMA page_size = 1024;"
@@ -1374,7 +1377,7 @@ static char *dynamic_triggers_1(int iTid, void *pArg){
   int nDrop = 0;
   int nCreate = 0;
 
-  opendb(&err, &db, "test.db", 0);
+  opendb(&err, &db, "test.db", 0, 0);
   while( !timetostop(&err) ){
     int i;
 
@@ -1427,7 +1430,7 @@ static char *dynamic_triggers_2(int iTid, void *pArg){
   int nInsert = 0;
   int nDelete = 0;
 
-  opendb(&err, &db, "test.db", 0);
+  opendb(&err, &db, "test.db", 0, 0);
   while( !timetostop(&err) ){
     do {
       iVal = (iVal+1)%100;
@@ -1452,7 +1455,7 @@ static void dynamic_triggers(int nMs){
   Sqlite db = {0};
   Threadset threads = {0};
 
-  opendb(&err, &db, "test.db", 1);
+  opendb(&err, &db, "test.db", 1, 0);
   sql_script(&err, &db, 
       "PRAGMA page_size = 1024;"
       "PRAGMA journal_mode = WAL;"
@@ -1492,6 +1495,7 @@ static void dynamic_triggers(int nMs){
 #include "tt3_lookaside1.c"
 #include "tt3_vacuum.c"
 #include "tt3_stress.c"
+#include "tt3_reuseschema.c"
 #include "tt3_shared.c"
 
 int main(int argc, char **argv){
@@ -1517,6 +1521,7 @@ int main(int argc, char **argv){
     { vacuum1,             "vacuum1", 10000 },
     { stress1,             "stress1", 10000 },
     { stress2,             "stress2", 60000 },
+    { reuse_schema_1,      "reuse_schema_1", 20000 },
     { shared1,             "shared1", 10000 },
   };
   static char *substArgv[] = { 0, "*", 0 };

test/tt3_checkpoint.c

@@ -70,7 +70,7 @@ static char *checkpoint_starvation_reader(int iTid, void *pArg){
   Error err = {0};
   Sqlite db = {0};
 
-  opendb(&err, &db, "test.db", 0);
+  opendb(&err, &db, "test.db", 0, 0);
   while( !timetostop(&err) ){
     i64 iCount1, iCount2;
     sql_script(&err, &db, "BEGIN");
@@ -96,7 +96,7 @@ static void checkpoint_starvation_main(int nMs, CheckpointStarvationCtx *p){
   int nInsert = 0;
   int i;
 
-  opendb(&err, &db, "test.db", 1);
+  opendb(&err, &db, "test.db", 1, 0);
   sql_script(&err, &db, 
       "PRAGMA page_size = 1024;"
       "PRAGMA journal_mode = WAL;"

test/tt3_index.c

@@ -19,7 +19,7 @@ static char *create_drop_index_thread(int iTid, void *pArg){
   Sqlite db = {0};                /* SQLite database connection */
 
   while( !timetostop(&err) ){
-    opendb(&err, &db, "test.db", 0);
+    opendb(&err, &db, "test.db", 0, 0);
 
     sql_script(&err, &db, 
       "DROP INDEX IF EXISTS i1;"
@@ -51,7 +51,7 @@ static void create_drop_index_1(int nMs){
   Sqlite db = {0};
   Threadset threads = {0};
 
-  opendb(&err, &db, "test.db", 1);
+  opendb(&err, &db, "test.db", 1, 0);
   sql_script(&err, &db, 
      "CREATE TABLE t11(a, b, c, d);"
      "WITH data(x) AS (SELECT 1 UNION ALL SELECT x+1 FROM data WHERE x<100) "

test/tt3_lookaside1.c

@@ -22,7 +22,7 @@ static char *lookaside1_thread_reader(int iTid, void *pArg){
   Error err = {0};                /* Error code and message */
   Sqlite db = {0};                /* SQLite database connection */
 
-  opendb(&err, &db, "test.db", 0);
+  opendb(&err, &db, "test.db", 0, 0);
 
   while( !timetostop(&err) ){
     sqlite3_stmt *pStmt = 0;
@@ -47,7 +47,7 @@ static char *lookaside1_thread_writer(int iTid, void *pArg){
   Error err = {0};                /* Error code and message */
   Sqlite db = {0};                /* SQLite database connection */
 
-  opendb(&err, &db, "test.db", 0);
+  opendb(&err, &db, "test.db", 0, 0);
 
   do{
     sql_script(&err, &db, 
@@ -68,7 +68,7 @@ static void lookaside1(int nMs){
   Sqlite db = {0};
   Threadset threads = {0};
 
-  opendb(&err, &db, "test.db", 1);
+  opendb(&err, &db, "test.db", 1, 0);
   sql_script(&err, &db, 
      "CREATE TABLE t1(x PRIMARY KEY) WITHOUT ROWID;"
      "WITH data(x,y) AS ("

test/tt3_reuseschema.c

@@ -0,0 +1,73 @@
+/*
+** 2014 December 9
+**
+** 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.
+**
+*************************************************************************
+**
+**     reuse_schema_1
+*/
+
+
+static char *reuse_schema_thread(int iTid, void *pArg){
+  Error err = {0};                /* Error code and message */
+  Sqlite db = {0};                /* SQLite database connection */
+  int iRep = 0;
+
+  while( !timetostop(&err) ){
+    int f = SQLITE_OPEN_READWRITE|SQLITE_OPEN_SHARED_SCHEMA;
+    opendb(&err, &db, "test.db", 0, f);
+
+    execsql_i64(&err, &db, "SELECT count(*) FROM t1");
+    sql_script(&err, &db, "ATTACH 'test.db2' AS aux");
+    execsql_i64(&err, &db, "SELECT count(*) FROM t1");
+
+    closedb(&err, &db);
+    iRep++;
+  }
+
+  print_and_free_err(&err);
+  return sqlite3_mprintf("%d", iRep);
+}
+
+static void reuse_schema_1(int nMs){
+  Error err = {0};
+  Sqlite db = {0};
+  Threadset threads = {0};
+
+  opendb(&err, &db, "test.db", 1, 0);
+  sql_script(&err, &db, 
+     "CREATE TABLE t1(a, b, c, d);"
+     "WITH data(x) AS (SELECT 1 UNION ALL SELECT x+1 FROM data WHERE x<100) "
+     "INSERT INTO t1 SELECT x,x,x,x FROM data;"
+  );
+  closedb(&err, &db);
+  opendb(&err, &db, "test.db2", 1, 0);
+  sql_script(&err, &db, 
+#ifdef SQLITE_ENABLE_FTS5
+     "CREATE VIRTUAL TABLE t2 USING fts5(a, b, c, d);"
+#else
+     "CREATE TABLE t2(a, b, c, d);"
+#endif
+     "WITH data(x) AS (SELECT 1 UNION ALL SELECT x+1 FROM data WHERE x<100) "
+     "INSERT INTO t2 SELECT x*2,x*2,x*2,x*2 FROM data;"
+  );
+  closedb(&err, &db);
+
+  setstoptime(&err, nMs);
+
+  launch_thread(&err, &threads, reuse_schema_thread, 0);
+  launch_thread(&err, &threads, reuse_schema_thread, 0);
+  launch_thread(&err, &threads, reuse_schema_thread, 0);
+  launch_thread(&err, &threads, reuse_schema_thread, 0);
+  launch_thread(&err, &threads, reuse_schema_thread, 0);
+
+  join_all_threads(&err, &threads);
+  sqlite3_enable_shared_cache(0);
+  print_and_free_err(&err);
+}

test/tt3_stress.c

@@ -21,7 +21,7 @@ static char *stress_thread_1(int iTid, void *pArg){
   Error err = {0};                /* Error code and message */
   Sqlite db = {0};                /* SQLite database connection */
 
-  opendb(&err, &db, "test.db", 0);
+  opendb(&err, &db, "test.db", 0, 0);
   while( !timetostop(&err) ){
     sql_script(&err, &db, "CREATE TABLE IF NOT EXISTS t1(a PRIMARY KEY, b)");
     clear_error(&err, SQLITE_LOCKED);
@@ -40,7 +40,7 @@ static char *stress_thread_2(int iTid, void *pArg){
   Error err = {0};                /* Error code and message */
   Sqlite db = {0};                /* SQLite database connection */
   while( !timetostop(&err) ){
-    opendb(&err, &db, "test.db", 0);
+    opendb(&err, &db, "test.db", 0, 0);
     sql_script(&err, &db, "SELECT * FROM sqlite_schema;");
     clear_error(&err, SQLITE_LOCKED);
     closedb(&err, &db);
@@ -59,7 +59,7 @@ static char *stress_thread_3(int iTid, void *pArg){
   int i1 = 0;
   int i2 = 0;
 
-  opendb(&err, &db, "test.db", 0);
+  opendb(&err, &db, "test.db", 0, 0);
   while( !timetostop(&err) ){
     sql_script(&err, &db, "SELECT * FROM t1 ORDER BY a;");
     i1++;
@@ -82,11 +82,11 @@ static char *stress_thread_4(int iTid, void *pArg){
   int i2 = 0;
   int iArg = PTR2INT(pArg);
 
-  opendb(&err, &db, "test.db", 0);
+  opendb(&err, &db, "test.db", 0, 0);
   while( !timetostop(&err) ){
     if( iArg ){
       closedb(&err, &db);
-      opendb(&err, &db, "test.db", 0);
+      opendb(&err, &db, "test.db", 0, 0);
     }
     sql_script(&err, &db, 
         "WITH loop(i) AS (SELECT 1 UNION ALL SELECT i+1 FROM loop LIMIT 200) "
@@ -113,12 +113,12 @@ static char *stress_thread_5(int iTid, void *pArg){
   int i1 = 0;
   int i2 = 0;
 
-  opendb(&err, &db, "test.db", 0);
+  opendb(&err, &db, "test.db", 0, 0);
   while( !timetostop(&err) ){
     i64 i = (i1 % 4);
     if( iArg ){
       closedb(&err, &db);
-      opendb(&err, &db, "test.db", 0);
+      opendb(&err, &db, "test.db", 0, 0);
     }
     execsql(&err, &db, "DELETE FROM t1 WHERE (rowid % 4)==:i", &i);
     i1++;
@@ -265,7 +265,7 @@ static char *stress2_workload19(int iTid, void *pArg){
   Sqlite db = {0};                /* SQLite database connection */
   const char *zDb = (const char*)pArg;
   while( !timetostop(&err) ){
-    opendb(&err, &db, zDb, 0);
+    opendb(&err, &db, zDb, 0, 0);
     sql_script(&err, &db, "SELECT * FROM sqlite_schema;");
     clear_error(&err, SQLITE_LOCKED);
     closedb(&err, &db);
@@ -290,7 +290,7 @@ static char *stress2_thread_wrapper(int iTid, void *pArg){
 
   while( !timetostop(&err) ){
     int cnt;
-    opendb(&err, &db, pCtx->zDb, 0);
+    opendb(&err, &db, pCtx->zDb, 0, 0);
     for(cnt=0; err.rc==SQLITE_OK && cnt<STRESS2_TABCNT; cnt++){
       pCtx->xProc(&err, &db, i1);
       i2 += (err.rc==SQLITE_OK);
@@ -342,7 +342,7 @@ static void stress2(int nMs){
   Threadset threads = {0};
 
   /* To make sure the db file is empty before commencing */
-  opendb(&err, &db, zDb, 1);
+  opendb(&err, &db, zDb, 1, 0);
   sql_script(&err, &db, 
       "CREATE TABLE IF NOT EXISTS t0(x PRIMARY KEY, y, z);"
       "CREATE INDEX IF NOT EXISTS i0 ON t0(y);"

test/tt3_vacuum.c

@@ -25,7 +25,7 @@ static char *vacuum1_thread_writer(int iTid, void *pArg){
   Sqlite db = {0};                /* SQLite database connection */
   i64 i = 0;
 
-  opendb(&err, &db, "test.db", 0);
+  opendb(&err, &db, "test.db", 0, 0);
   while( !timetostop(&err) ){
     i++;
 
@@ -52,7 +52,7 @@ static char *vacuum1_thread_writer(int iTid, void *pArg){
 static char *vacuum1_thread_vacuumer(int iTid, void *pArg){
   Error err = {0};                /* Error code and message */
   Sqlite db = {0};                /* SQLite database connection */
-  opendb(&err, &db, "test.db", 0);
+  opendb(&err, &db, "test.db", 0, 0);
 
   do{
     sql_script(&err, &db, "VACUUM");
@@ -69,7 +69,7 @@ static void vacuum1(int nMs){
   Sqlite db = {0};
   Threadset threads = {0};
 
-  opendb(&err, &db, "test.db", 1);
+  opendb(&err, &db, "test.db", 1, 0);
   sql_script(&err, &db, 
      "CREATE TABLE t1(x PRIMARY KEY, y BLOB);"
      "CREATE INDEX i1 ON t1(y);"

test/whereG.test

@@ -311,6 +311,20 @@ do_execsql_test 8.9 {
 do_execsql_test 8.10 {
   SELECT * FROM t0 WHERE likelihood(t0.rowid <= '0', 0.5);
 } {}
+# Forum https://sqlite.org/forum/forumpost/45ec3d9788
+reset_db
+do_execsql_test 8.11 {
+  CREATE TABLE t1(c0 INT);
+  INSERT INTO t1(c0) VALUES (NULL);
+  CREATE INDEX i46 ON t1(CAST( (c0 IS TRUE) AS TEXT));
+  CREATE VIEW v0(c2) AS SELECT CAST( (c0 IS TRUE) AS TEXT ) FROM t1;
+}
+do_execsql_test 8.12 {
+  SELECT quote(c0), quote(c2) FROM t1, v0 WHERE  (0 < LIKELY(v0.c2));
+} {NULL '0'} 
+do_execsql_test 8.13 {
+  SELECT quote(c0), quote(c2) FROM t1, v0 WHERE  (0 < LIKELY(v0.c2)) IS TRUE;
+} {NULL '0'}
 
 # 2019-12-31: assertion fault discovered by Yongheng's fuzzer.
 # Harmless memIsValid() due to the code generators failure to

tool/mkctimec.tcl

@@ -7,6 +7,13 @@
 # definition used in src/ctime.c, run this script from
 # the checkout root. It generates src/ctime.c .
 #
+# Results are normally written into src/ctime.c.  But if an argument is
+# provided, results are written there instead.  Examples:
+#
+#    tclsh tool/mkctimec.tcl                ;# <-- results to src/ctime.c
+#
+#    tclsh tool/mkctimec.tcl /dev/tty       ;# <-- results to the terminal
+#
 
 
 set ::headWarning {/* DO NOT EDIT!
@@ -429,10 +436,15 @@ foreach v $value2_options {
 }]
 }
 
-set ctime_c "src/ctime.c"
+if {$argc>0} {
+  set destfile [lindex $argv 0]
+} else {
+  set destfile "[file dir [file dir [file normal $argv0]]]/src/ctime.c"
+  puts "Overwriting $destfile..."
+}
 
-if {[catch {set cfd [open $ctime_c w]}]!=0} {
-  puts stderr "File '$ctime_c' unwritable."
+if {[catch {set cfd [open $destfile w]}]!=0} {
+  puts stderr "File '$destfile' unwritable."
   exit 1;
 }
 

tool/mkpragmatab.tcl

@@ -9,10 +9,18 @@
 # Then add the extra "case PragTyp_XXXXX:" and subsequent code for the
 # new pragma in ../src/pragma.c.
 #
+# The results are normally written into the ../src/pragma.h file.  However,
+# if an alternative output file name is provided as an argument, then
+# results are written into the alternative.  For example:
+#
+#     tclsh tool/mkpragmatab.tcl            ;# <--- Results to src/pragma.h
+#
+#     tclsh tool/mkpragmatab.tcl /dev/tty   ;# <-- results to terminal
+#
 
 # Flag meanings:
 set flagMeaning(NeedSchema) {Force schema load before running}
-set flagMeaning(ReadOnly)   {Read-only HEADER_VALUE}
+set flagMeaning(OneSchema)  {Only a single schema required}
 set flagMeaning(Result0)    {Acts as query when no argument}
 set flagMeaning(Result1)    {Acts as query when has one argument}
 set flagMeaning(SchemaReq)  {Schema required - "main" is default}
@@ -150,7 +158,7 @@ set pragma_def {
   ARG:  SQLITE_CellSizeCk
 
   NAME: default_cache_size
-  FLAG: NeedSchema Result0 SchemaReq NoColumns1
+  FLAG: NeedSchema Result0 SchemaReq NoColumns1 OneSchema
   COLS: cache_size
   IF:   !defined(SQLITE_OMIT_PAGER_PRAGMAS) && !defined(SQLITE_OMIT_DEPRECATED)
 
@@ -163,12 +171,12 @@ set pragma_def {
   IF:   !defined(SQLITE_OMIT_PAGER_PRAGMAS)
 
   NAME: page_count
-  FLAG: NeedSchema Result0 SchemaReq
+  FLAG: NeedSchema Result0 SchemaReq OneSchema
   IF:   !defined(SQLITE_OMIT_PAGER_PRAGMAS)
 
   NAME: max_page_count
   TYPE: PAGE_COUNT
-  FLAG: NeedSchema Result0 SchemaReq
+  FLAG: NeedSchema Result0 SchemaReq OneSchema
   IF:   !defined(SQLITE_OMIT_PAGER_PRAGMAS)
 
   NAME: locking_mode
@@ -176,7 +184,7 @@ set pragma_def {
   IF:   !defined(SQLITE_OMIT_PAGER_PRAGMAS)
 
   NAME: journal_mode
-  FLAG: NeedSchema Result0 SchemaReq
+  FLAG: NeedSchema Result0 SchemaReq OneSchema
   IF:   !defined(SQLITE_OMIT_PAGER_PRAGMAS)
 
   NAME: journal_size_limit
@@ -184,18 +192,18 @@ set pragma_def {
   IF:   !defined(SQLITE_OMIT_PAGER_PRAGMAS)
 
   NAME: cache_size
-  FLAG: NeedSchema Result0 SchemaReq NoColumns1
+  FLAG: NeedSchema Result0 SchemaReq NoColumns1 OneSchema
   IF:   !defined(SQLITE_OMIT_PAGER_PRAGMAS)
 
   NAME: mmap_size
   IF:   !defined(SQLITE_OMIT_PAGER_PRAGMAS)
 
   NAME: auto_vacuum
-  FLAG: NeedSchema Result0 SchemaReq NoColumns1
+  FLAG: NeedSchema Result0 SchemaReq NoColumns1 OneSchema
   IF:   !defined(SQLITE_OMIT_AUTOVACUUM)
 
   NAME: incremental_vacuum
-  FLAG: NeedSchema NoColumns
+  FLAG: NeedSchema NoColumns OneSchema
   IF:   !defined(SQLITE_OMIT_AUTOVACUUM)
 
   NAME: temp_store
@@ -215,7 +223,7 @@ set pragma_def {
   IF:   !defined(SQLITE_OMIT_PAGER_PRAGMAS) && SQLITE_ENABLE_LOCKING_STYLE
 
   NAME: synchronous
-  FLAG: NeedSchema Result0 SchemaReq NoColumns1
+  FLAG: NeedSchema Result0 SchemaReq NoColumns1 OneSchema
   IF:   !defined(SQLITE_OMIT_PAGER_PRAGMAS)
 
   NAME: table_info
@@ -238,7 +246,7 @@ set pragma_def {
   IF:   !defined(SQLITE_OMIT_SCHEMA_PRAGMAS)
 
   NAME: stats
-  FLAG: NeedSchema Result0 SchemaReq
+  FLAG: NeedSchema Result0 SchemaReq OneSchema
   COLS: tbl idx wdth hght flgs
   IF:   !defined(SQLITE_OMIT_SCHEMA_PRAGMAS) && defined(SQLITE_DEBUG)
 
@@ -290,7 +298,7 @@ set pragma_def {
   IF:   !defined(SQLITE_OMIT_SCHEMA_PRAGMAS)
 
   NAME: foreign_key_list
-  FLAG: NeedSchema Result1 SchemaOpt
+  FLAG: NeedSchema Result1 SchemaOpt OneSchema
   COLS: id seq table from to on_update on_delete match
   IF:   !defined(SQLITE_OMIT_FOREIGN_KEY)
 
@@ -336,14 +344,14 @@ set pragma_def {
 
   NAME: data_version
   TYPE: HEADER_VALUE
-  ARG:  BTREE_DATA_VERSION
-  FLAG: ReadOnly Result0
+  ARG:  BTREE_DATA_VERSION|PRAGMA_HEADER_VALUE_READONLY
+  FLAG: Result0
   IF:   !defined(SQLITE_OMIT_SCHEMA_VERSION_PRAGMAS)
 
   NAME: freelist_count
   TYPE: HEADER_VALUE
-  ARG:  BTREE_FREE_PAGE_COUNT
-  FLAG: ReadOnly Result0
+  ARG:  BTREE_FREE_PAGE_COUNT|PRAGMA_HEADER_VALUE_READONLY
+  FLAG: Result0
   IF:   !defined(SQLITE_OMIT_SCHEMA_VERSION_PRAGMAS)
 
   NAME: application_id
@@ -357,7 +365,7 @@ set pragma_def {
   IF:   !defined(SQLITE_OMIT_COMPILEOPTION_DIAGS)
 
   NAME: wal_checkpoint
-  FLAG: NeedSchema
+  FLAG: NeedSchema OneSchema
   COLS: busy log checkpointed
   IF:   !defined(SQLITE_OMIT_WAL)
 
@@ -402,8 +410,12 @@ set pragma_def {
 
 # Open the output file
 #
-set destfile "[file dir [file dir [file normal $argv0]]]/src/pragma.h"
-puts "Overwriting $destfile with new pragma table..."
+if {$argc>0} {
+  set destfile [lindex $argv 0]
+} else {
+  set destfile "[file dir [file dir [file normal $argv0]]]/src/pragma.h"
+  puts "Overwriting $destfile with new pragma table..."
+}
 set fd [open $destfile wb]
 puts $fd {/* DO NOT EDIT!
 ** This file is automatically generated by the script at
@@ -516,6 +528,12 @@ foreach f [lsort [array names allflags]] {
   set fv [expr {$fv*2}]
 }
 
+puts $fd "\n/* For PragTyp_HEADER_VALUE pragmas the Pragma.iArg value is set"
+puts $fd "** to the index of the header field to access (always 10 or less)."
+puts $fd "** Ored with HEADER_VALUE_READONLY if the field is read only. */"
+puts $fd "#define PRAGMA_HEADER_VALUE_READONLY 0x0100"
+puts $fd "#define PRAGMA_HEADER_VALUE_MASK 0x00FF\n"
+
 # Sort the column lists so that longer column lists occur first
 #
 proc colscmp {a b} {

tool/srctree-check.tcl

@@ -27,12 +27,15 @@ proc readfile {filename} {
 # Find the root of the tree.
 #
 set ROOT [file dir [file dir [file normalize $argv0]]]
-cd $ROOT
 
 # Name of the TCL interpreter
 #
 set TCLSH [info nameofexe]
 
+# Number of errors seen.
+#
+set NERR 0
+
 ######################### autoconf/tea/configure.ac ###########################
 
 set confac [readfile $ROOT/autoconf/tea/configure.ac]
@@ -42,38 +45,46 @@ append pattern [string trim $vers]
 append pattern {])}
 if {[string first $pattern $confac]<=0} {
   puts "ERROR: ./autoconf/tea/configure.ac does not agree with ./VERSION"
-  exit 1
+  puts "...... Fix: manually edit ./autoconf/tea/configure.ac to"
+  incr NERR
 }
 
 ######################### autoconf/Makefile.msc ###############################
 
 set f1 [readfile $ROOT/autoconf/Makefile.msc]
-exec mv $ROOT/autoconf/Makefile.msc $ROOT/autoconf/Makefile.msc.tmp
-exec $TCLSH $ROOT/tool/mkmsvcmin.tcl
-set f2 [readfile $ROOT/autoconf/Makefile.msc]
-exec mv $ROOT/autoconf/Makefile.msc.tmp $ROOT/autoconf/Makefile.msc
+exec $TCLSH $ROOT/tool/mkmsvcmin.tcl $ROOT/Makefile.msc tmp1.txt
+set f2 [readfile tmp1.txt]
+file delete tmp1.txt
 if {$f1 != $f2} {
   puts "ERROR: ./autoconf/Makefile.msc does not agree with ./Makefile.msc"
+  puts "...... Fix: tclsh tool/mkmsvcmin.tcl"
+  incr NERR
 }
 
 ######################### src/pragma.h ########################################
 
 set f1 [readfile $ROOT/src/pragma.h]
-exec mv $ROOT/src/pragma.h $ROOT/src/pragma.h.tmp
-exec $TCLSH $ROOT/tool/mkpragmatab.tcl
-set f2 [readfile $ROOT/src/pragma.h]
-exec mv $ROOT/src/pragma.h.tmp $ROOT/src/pragma.h
+exec $TCLSH $ROOT/tool/mkpragmatab.tcl tmp2.txt
+set f2 [readfile tmp2.txt]
+file delete tmp2.txt
 if {$f1 != $f2} {
   puts "ERROR: ./src/pragma.h does not agree with ./tool/mkpragmatab.tcl"
+  puts "...... Fix: tclsh tool/mkpragmatab.tcl"
+  incr NERR
 }
 
 ######################### src/ctime.c ########################################
 
 set f1 [readfile $ROOT/src/ctime.c]
-exec mv $ROOT/src/ctime.c $ROOT/src/ctime.c.tmp
-exec $TCLSH $ROOT/tool/mkctimec.tcl
-set f2 [readfile $ROOT/src/ctime.c]
-exec mv $ROOT/src/ctime.c.tmp $ROOT/src/ctime.c
+exec $TCLSH $ROOT/tool/mkctimec.tcl tmp3.txt
+set f2 [readfile tmp3.txt]
+file delete tmp3.txt
 if {$f1 != $f2} {
   puts "ERROR: ./src/ctime.c does not agree with ./tool/mkctimec.tcl"
+  puts ".....  Fix: tclsh tool/mkctimec.tcl"
+  incr NERR
 }
+
+# If any errors are seen, exit 1 so that the build will fail.
+#
+if {$NERR>0} {exit 1}