Experimental multi-threaded sorting changes to begin merging PMAs before SorterRewind() is called.

FossilOrigin-Name: cbfc0f6d49b6607bb4eb45bfe4c258e39ac27403
Fix harmless compiler warnings.
2014-04-07 18:44:00 +00:00 · 2014-04-04 22:44:59 +00:00 · 2014-04-04 21:40:38 +00:00 · 2014-04-04 18:37:36 +00:00 · 2014-04-04 18:20:35 +00:00 · 2014-04-04 14:12:52 +00:00
73 changed files with 4064 additions and 1071 deletions
@@ -177,7 +177,7 @@ LIBOBJS0 = alter.lo analyze.lo attach.lo auth.lo \
         notify.lo opcodes.lo os.lo os_unix.lo os_win.lo \
         pager.lo parse.lo pcache.lo pcache1.lo pragma.lo prepare.lo printf.lo \
         random.lo resolve.lo rowset.lo rtree.lo select.lo status.lo \
-         table.lo tokenize.lo trigger.lo \
+         table.lo threads.lo tokenize.lo trigger.lo \
         update.lo util.lo vacuum.lo \
         vdbe.lo vdbeapi.lo vdbeaux.lo vdbeblob.lo vdbemem.lo vdbesort.lo \
         vdbetrace.lo wal.lo walker.lo where.lo utf.lo vtab.lo
@@ -261,6 +261,7 @@ SRC = \
  $(TOP)/src/sqliteInt.h \
  $(TOP)/src/sqliteLimit.h \
  $(TOP)/src/table.c \
+  $(TOP)/src/threads.c \
  $(TOP)/src/tclsqlite.c \
  $(TOP)/src/tokenize.c \
  $(TOP)/src/trigger.c \
@@ -732,6 +733,9 @@ status.lo:	$(TOP)/src/status.c $(HDR)
 table.lo:	$(TOP)/src/table.c $(HDR)
 	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/table.c

+threads.lo:	$(TOP)/src/threads.c $(HDR)
+	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/threads.c
+
 tokenize.lo:	$(TOP)/src/tokenize.c keywordhash.h $(HDR)
 	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/tokenize.c

@@ -564,7 +564,7 @@ LIBOBJS0 = vdbe.lo parse.lo alter.lo analyze.lo attach.lo auth.lo \
         notify.lo opcodes.lo os.lo os_unix.lo os_win.lo \
         pager.lo pcache.lo pcache1.lo pragma.lo prepare.lo printf.lo \
         random.lo resolve.lo rowset.lo rtree.lo select.lo status.lo \
-         table.lo tokenize.lo trigger.lo \
+         table.lo threads.o tokenize.lo trigger.lo \
         update.lo util.lo vacuum.lo \
         vdbeapi.lo vdbeaux.lo vdbeblob.lo vdbemem.lo vdbesort.lo \
         vdbetrace.lo wal.lo walker.lo where.lo utf.lo vtab.lo
@@ -659,6 +659,7 @@ SRC = \
  $(TOP)\src\sqliteInt.h \
  $(TOP)\src\sqliteLimit.h \
  $(TOP)\src\table.c \
+  $(TOP)\src\threads.c \
  $(TOP)\src\tclsqlite.c \
  $(TOP)\src\tokenize.c \
  $(TOP)\src\trigger.c \
@@ -1139,6 +1140,9 @@ status.lo:	$(TOP)\src\status.c $(HDR)
 table.lo:	$(TOP)\src\table.c $(HDR)
 	$(LTCOMPILE) -c $(TOP)\src\table.c

+threads.lo:	$(TOP)\src\threads.c $(HDR)
+	$(LTCOMPILE) -c $(TOP)\src\threads.c
+
 tokenize.lo:	$(TOP)\src\tokenize.c keywordhash.h $(HDR)
 	$(LTCOMPILE) -c $(TOP)\src\tokenize.c

@@ -1 +1 @@
-3.8.4
+3.8.5
@@ -1,6 +1,6 @@
 #! /bin/sh
 # Guess values for system-dependent variables and create Makefiles.
-# Generated by GNU Autoconf 2.62 for sqlite 3.8.4.
+# Generated by GNU Autoconf 2.62 for sqlite 3.8.5.
 #
 # Copyright (C) 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001,
 # 2002, 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
@@ -743,8 +743,8 @@ SHELL=${CONFIG_SHELL-/bin/sh}
 # Identity of this package.
 PACKAGE_NAME='sqlite'
 PACKAGE_TARNAME='sqlite'
-PACKAGE_VERSION='3.8.4'
-PACKAGE_STRING='sqlite 3.8.4'
+PACKAGE_VERSION='3.8.5'
+PACKAGE_STRING='sqlite 3.8.5'
 PACKAGE_BUGREPORT=''

 # Factoring default headers for most tests.
@@ -1483,7 +1483,7 @@ 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 3.8.4 to adapt to many kinds of systems.
+\`configure' configures sqlite 3.8.5 to adapt to many kinds of systems.

 Usage: $0 [OPTION]... [VAR=VALUE]...

@@ -1548,7 +1548,7 @@ fi

 if test -n "$ac_init_help"; then
  case $ac_init_help in
-     short | recursive ) echo "Configuration of sqlite 3.8.4:";;
+     short | recursive ) echo "Configuration of sqlite 3.8.5:";;
   esac
  cat <<\_ACEOF

@@ -1664,7 +1664,7 @@ fi
 test -n "$ac_init_help" && exit $ac_status
 if $ac_init_version; then
  cat <<\_ACEOF
-sqlite configure 3.8.4
+sqlite configure 3.8.5
 generated by GNU Autoconf 2.62

 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001,
@@ -1678,7 +1678,7 @@ 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 3.8.4, which was
+It was created by sqlite $as_me 3.8.5, which was
 generated by GNU Autoconf 2.62.  Invocation command line was

  $ $0 $@
@@ -14021,7 +14021,7 @@ exec 6>&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 3.8.4, which was
+This file was extended by sqlite $as_me 3.8.5, which was
 generated by GNU Autoconf 2.62.  Invocation command line was

  CONFIG_FILES    = $CONFIG_FILES
@@ -14074,7 +14074,7 @@ Report bugs to <bug-autoconf@gnu.org>."
 _ACEOF
 cat >>$CONFIG_STATUS <<_ACEOF || ac_write_fail=1
 ac_cs_version="\\
-sqlite config.status 3.8.4
+sqlite config.status 3.8.5
 configured by $0, generated by GNU Autoconf 2.62,
  with options \\"`$as_echo "$ac_configure_args" | sed 's/^ //; s/[\\""\`\$]/\\\\&/g'`\\"

@@ -1410,10 +1410,7 @@ static int fts3InitVtab(
  ** addition of a %_stat table so that it can use incremental merge.
  */
  if( !isFts4 && !isCreate ){
-    int rc2 = SQLITE_OK;
-    fts3DbExec(&rc2, db, "SELECT 1 FROM %Q.'%q_stat' WHERE id=2",
-               p->zDb, p->zName);
-    if( rc2==SQLITE_OK ) p->bHasStat = 1;
+    p->bHasStat = 2;
  }

  /* Figure out the page-size for the database. This is required in order to
@@ -3320,7 +3317,34 @@ static int fts3SyncMethod(sqlite3_vtab *pVtab){
 }

 /*
-** Implementation of xBegin() method. This is a no-op.
+** If it is currently unknown whether or not the FTS table has an %_stat
+** table (if p->bHasStat==2), attempt to determine this (set p->bHasStat
+** to 0 or 1). Return SQLITE_OK if successful, or an SQLite error code
+** if an error occurs.
+*/
+static int fts3SetHasStat(Fts3Table *p){
+  int rc = SQLITE_OK;
+  if( p->bHasStat==2 ){
+    const char *zFmt ="SELECT 1 FROM %Q.sqlite_master WHERE tbl_name='%q_stat'";
+    char *zSql = sqlite3_mprintf(zFmt, p->zDb, p->zName);
+    if( zSql ){
+      sqlite3_stmt *pStmt = 0;
+      rc = sqlite3_prepare_v2(p->db, zSql, -1, &pStmt, 0);
+      if( rc==SQLITE_OK ){
+        int bHasStat = (sqlite3_step(pStmt)==SQLITE_ROW);
+        rc = sqlite3_finalize(pStmt);
+        if( rc==SQLITE_OK ) p->bHasStat = bHasStat;
+      }
+      sqlite3_free(zSql);
+    }else{
+      rc = SQLITE_NOMEM;
+    }
+  }
+  return rc;
+}
+
+/*
+** Implementation of xBegin() method. 
 */
 static int fts3BeginMethod(sqlite3_vtab *pVtab){
  Fts3Table *p = (Fts3Table*)pVtab;
@@ -3331,7 +3355,7 @@ static int fts3BeginMethod(sqlite3_vtab *pVtab){
  TESTONLY( p->inTransaction = 1 );
  TESTONLY( p->mxSavepoint = -1; );
  p->nLeafAdd = 0;
-  return SQLITE_OK;
+  return fts3SetHasStat(p);
 }

 /*
@@ -3580,6 +3604,10 @@ static int fts3RenameMethod(
  sqlite3 *db = p->db;            /* Database connection */
  int rc;                         /* Return Code */

+  /* At this point it must be known if the %_stat table exists or not.
+  ** So bHasStat may not be 2.  */
+  rc = fts3SetHasStat(p);
+  
  /* As it happens, the pending terms table is always empty here. This is
  ** because an "ALTER TABLE RENAME TABLE" statement inside a transaction 
  ** always opens a savepoint transaction. And the xSavepoint() method 
@@ -3587,7 +3615,9 @@ static int fts3RenameMethod(
  ** PendingTermsFlush() in in case that changes.
  */
  assert( p->nPendingData==0 );
-  rc = sqlite3Fts3PendingTermsFlush(p);
+  if( rc==SQLITE_OK ){
+    rc = sqlite3Fts3PendingTermsFlush(p);
+  }

  if( p->zContentTbl==0 ){
    fts3DbExec(&rc, db,
@@ -223,7 +223,7 @@ struct Fts3Table {

  int nNodeSize;                  /* Soft limit for node size */
  u8 bFts4;                       /* True for FTS4, false for FTS3 */
-  u8 bHasStat;                    /* True if %_stat table exists */
+  u8 bHasStat;                    /* True if %_stat table exists (2==unknown) */
  u8 bHasDocsize;                 /* True if %_docsize table exists */
  u8 bDescIdx;                    /* True if doclists are in reverse order */
  u8 bIgnoreSavepoint;            /* True to ignore xSavepoint invocations */
@@ -5271,6 +5271,10 @@ int sqlite3Fts3UpdateMethod(
  int nChng = 0;                  /* Net change in number of documents */
  int bInsertDone = 0;

+  /* At this point it must be known if the %_stat table exists or not.
+  ** So bHasStat may not be 2.  */
+  assert( p->bHasStat==0 || p->bHasStat==1 );
+
  assert( p->pSegments==0 );
  assert( 
      nArg==1                     /* DELETE operations */
@@ -2947,26 +2947,32 @@ static int rtreeRename(sqlite3_vtab *pVtab, const char *zNewName){
 ** on sqlite_stat1 data. Otherwise, use RTREE_DEFAULT_ROWEST.
 */
 static int rtreeQueryStat1(sqlite3 *db, Rtree *pRtree){
-  const char *zSql = "SELECT stat FROM sqlite_stat1 WHERE tbl= ? || '_rowid'";
+  const char *zFmt = "SELECT stat FROM %Q.sqlite_stat1 WHERE tbl = '%q_rowid'";
+  char *zSql;
  sqlite3_stmt *p;
  int rc;
  i64 nRow = 0;

-  rc = sqlite3_prepare_v2(db, zSql, -1, &p, 0);
-  if( rc==SQLITE_OK ){
-    sqlite3_bind_text(p, 1, pRtree->zName, -1, SQLITE_STATIC);
-    if( sqlite3_step(p)==SQLITE_ROW ) nRow = sqlite3_column_int64(p, 0);
-    rc = sqlite3_finalize(p);
-  }else if( rc!=SQLITE_NOMEM ){
-    rc = SQLITE_OK;
-  }
-
-  if( rc==SQLITE_OK ){
-    if( nRow==0 ){
-      pRtree->nRowEst = RTREE_DEFAULT_ROWEST;
-    }else{
-      pRtree->nRowEst = MAX(nRow, RTREE_MIN_ROWEST);
+  zSql = sqlite3_mprintf(zFmt, pRtree->zDb, pRtree->zName);
+  if( zSql==0 ){
+    rc = SQLITE_NOMEM;
+  }else{
+    rc = sqlite3_prepare_v2(db, zSql, -1, &p, 0);
+    if( rc==SQLITE_OK ){
+      if( sqlite3_step(p)==SQLITE_ROW ) nRow = sqlite3_column_int64(p, 0);
+      rc = sqlite3_finalize(p);
+    }else if( rc!=SQLITE_NOMEM ){
+      rc = SQLITE_OK;
    }
+
+    if( rc==SQLITE_OK ){
+      if( nRow==0 ){
+        pRtree->nRowEst = RTREE_DEFAULT_ROWEST;
+      }else{
+        pRtree->nRowEst = MAX(nRow, RTREE_MIN_ROWEST);
+      }
+    }
+    sqlite3_free(zSql);
  }

  return rc;
@@ -3235,6 +3241,8 @@ static int rtreeInit(
  if( rc==SQLITE_OK ){
    *ppVtab = (sqlite3_vtab *)pRtree;
  }else{
+    assert( *ppVtab==0 );
+    assert( pRtree->nBusy==1 );
    rtreeRelease(pRtree);
  }
  return rc;
@@ -158,5 +158,117 @@ do_execsql_test 4.3 {
  SELECT b, a FROM t2 LEFT JOIN t1 ON (+a = +b);
 } {1 1 3 {}}

+#--------------------------------------------------------------------
+# Test that the sqlite_stat1 data is used correctly.
+#
+reset_db
+do_execsql_test 5.1 {
+  CREATE TABLE t1(x PRIMARY KEY, y);
+  CREATE VIRTUAL TABLE rt USING rtree(id, x1, x2);
+
+  INSERT INTO t1(x) VALUES(1);
+  INSERT INTO t1(x) SELECT x+1 FROM t1;   --   2
+  INSERT INTO t1(x) SELECT x+2 FROM t1;   --   4
+  INSERT INTO t1(x) SELECT x+4 FROM t1;   --   8
+  INSERT INTO t1(x) SELECT x+8 FROM t1;   --  16
+  INSERT INTO t1(x) SELECT x+16 FROM t1;  --  32
+  INSERT INTO t1(x) SELECT x+32 FROM t1;  --  64
+  INSERT INTO t1(x) SELECT x+64 FROM t1;  -- 128
+  INSERT INTO t1(x) SELECT x+128 FROM t1; -- 256
+  INSERT INTO t1(x) SELECT x+256 FROM t1; -- 512
+  INSERT INTO t1(x) SELECT x+512 FROM t1; --1024
+
+  INSERT INTO rt SELECT x, x, x+1 FROM t1 WHERE x<=5;
+}
+
+# First test a query with no ANALYZE data at all. The outer loop is
+# real table "t1".
+#
+do_eqp_test 5.2 {
+  SELECT * FROM t1, rt WHERE x==id;
+} {
+  0 0 0 {SCAN TABLE t1} 
+  0 1 1 {SCAN TABLE rt VIRTUAL TABLE INDEX 1:}
+}
+
+# Now create enough ANALYZE data to tell SQLite that virtual table "rt"
+# contains very few rows. This causes it to move "rt" to the outer loop.
+#
+do_execsql_test 5.3 {
+  ANALYZE;
+  DELETE FROM sqlite_stat1 WHERE tbl='t1';
+}
+db close
+sqlite3 db test.db
+do_eqp_test 5.4 {
+  SELECT * FROM t1, rt WHERE x==id;
+} {
+  0 0 1 {SCAN TABLE rt VIRTUAL TABLE INDEX 2:} 
+  0 1 0 {SEARCH TABLE t1 USING INDEX sqlite_autoindex_t1_1 (x=?)}
+}
+
+# Delete the ANALYZE data. "t1" should be the outer loop again.
+#
+do_execsql_test 5.5 { DROP TABLE sqlite_stat1; }
+db close
+sqlite3 db test.db
+do_eqp_test 5.6 {
+  SELECT * FROM t1, rt WHERE x==id;
+} {
+  0 0 0 {SCAN TABLE t1} 
+  0 1 1 {SCAN TABLE rt VIRTUAL TABLE INDEX 1:}
+}
+
+# This time create and attach a database that contains ANALYZE data for
+# tables of the same names as those used internally by virtual table
+# "rt". Check that the rtree module is not fooled into using this data.
+# Table "t1" should remain the outer loop.
+#
+do_test 5.7 {
+  db backup test.db2
+  sqlite3 db2 test.db2
+  db2 eval {
+    ANALYZE;
+    DELETE FROM sqlite_stat1 WHERE tbl='t1';
+  }
+  db2 close
+  db close
+  sqlite3 db test.db
+  execsql { ATTACH 'test.db2' AS aux; }
+} {}
+do_eqp_test 5.8 {
+  SELECT * FROM t1, rt WHERE x==id;
+} {
+  0 0 0 {SCAN TABLE t1} 
+  0 1 1 {SCAN TABLE rt VIRTUAL TABLE INDEX 1:}
+}
+
+#--------------------------------------------------------------------
+# Test that having a second connection drop the sqlite_stat1 table
+# before it is required by rtreeConnect() does not cause problems.
+#
+ifcapable rtree {
+  reset_db
+  do_execsql_test 6.1 {
+    CREATE TABLE t1(x);
+    CREATE VIRTUAL TABLE rt USING rtree(id, x1, x2);
+    INSERT INTO t1 VALUES(1);
+    INSERT INTO rt VALUES(1,2,3);
+    ANALYZE;
+  }
+  db close
+  sqlite3 db test.db
+  do_execsql_test 6.2 { SELECT * FROM t1 } {1}
+  
+  do_test 6.3 {
+    sqlite3 db2 test.db
+    db2 eval { DROP TABLE sqlite_stat1 }
+    db2 close
+    execsql { SELECT * FROM rt }
+  } {1 2.0 3.0}
+  db close
+}
+
+
 finish_test

@@ -0,0 +1,57 @@
+# 2014 March 11
+#
+# 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.
+#
+#***********************************************************************
+#
+# Miscellaneous tests for errors in the rtree constructor.
+#
+
+
+if {![info exists testdir]} {
+  set testdir [file join [file dirname [info script]] .. .. test]
+} 
+source [file join [file dirname [info script]] rtree_util.tcl]
+source $testdir/tester.tcl
+source $testdir/lock_common.tcl
+ifcapable !rtree {
+  finish_test
+  return
+}
+set testprefix rtreeD
+
+#-------------------------------------------------------------------------
+# Test that if an SQLITE_BUSY is encountered within the vtable 
+# constructor, a relevant error message is returned.
+#
+do_multiclient_test tn {
+  do_test 1.$tn.1 {
+    sql1 {
+      CREATE TABLE t1(a, b);
+      INSERT INTO t1 VALUES(1,2);
+      CREATE VIRTUAL TABLE rt USING rtree(id, minx, maxx, miny, maxy);
+      INSERT INTO rt VALUES(1,2,3,4,5);
+    }
+  } {}
+
+  do_test 1.$tn.2 {
+    sql2 { SELECT * FROM t1; }
+  } {1 2}
+
+  do_test 1.$tn.3 {
+    sql1 { BEGIN EXCLUSIVE; INSERT INTO t1 VALUES(3, 4); }
+  } {}
+
+  do_test 1.$tn.4 {
+    list [catch { sql2 { SELECT * FROM rt } } msg] $msg
+  } {1 {database is locked}}
+}
+
+finish_test
+
+
@@ -66,7 +66,7 @@ LIBOBJ+= vdbe.o parse.o \
         notify.o opcodes.o os.o os_unix.o os_win.o \
         pager.o pcache.o pcache1.o pragma.o prepare.o printf.o \
         random.o resolve.o rowset.o rtree.o select.o status.o \
-         table.o tokenize.o trigger.o \
+         table.o threads.o tokenize.o trigger.o \
         update.o util.o vacuum.o \
         vdbeapi.o vdbeaux.o vdbeblob.o vdbemem.o vdbesort.o \
 	 vdbetrace.o wal.o walker.o where.o utf.o vtab.o
@@ -144,6 +144,7 @@ SRC = \
  $(TOP)/src/sqliteLimit.h \
  $(TOP)/src/table.c \
  $(TOP)/src/tclsqlite.c \
+  $(TOP)/src/threads.c \
  $(TOP)/src/tokenize.c \
  $(TOP)/src/trigger.c \
  $(TOP)/src/utf.c \
@@ -1,12 +1,12 @@
-C Version\s3.8.4
-D 2014-03-10T12:20:37.813
+C Experimental\smulti-threaded\ssorting\schanges\sto\sbegin\smerging\sPMAs\sbefore\sSorterRewind()\sis\scalled.
+D 2014-04-07T18:44:00.443
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
-F Makefile.in 2ef13430cd359f7b361bb863504e227b25cc7f81
+F Makefile.in ad0921c4b2780d01868cf69b419a4f102308d125
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
-F Makefile.msc fdacba6fb574868c71fde6db6b77789a383a4c19
+F Makefile.msc 153eb9b9725bc7b8e4dbe963219298e0c4a644b0
 F Makefile.vxworks db21ed42a01d5740e656b16f92cb5d8d5e5dd315
 F README.md 64f270c43c38c46de749e419c22f0ae2f4499fe8
-F VERSION 0dc30ad5cf90736d5fd9e540c9f05c542658abe7
+F VERSION 9f823c026c6a32fc5f84d212a8aae0a221dba45c
 F aclocal.m4 a5c22d164aff7ed549d53a90fa56d56955281f50
 F addopcodes.awk 9eb448a552d5c0185cf62c463f9c173cedae3811
 F art/sqlite370.eps aa97a671332b432a54e1d74ff5e8775be34200c2
@@ -38,7 +38,7 @@ F autoconf/tea/win/rules.vc c511f222b80064096b705dbeb97060ee1d6b6d63
 F config.guess 226d9a188c6196f3033ffc651cbc9dcee1a42977
 F config.h.in 0921066a13130082764ab4ab6456f7b5bebe56de
 F config.sub 9ebe4c3b3dab6431ece34f16828b594fb420da55
-F configure e12e1a4f031354f9af735bcb377941a72dc2cca5 x
+F configure 5de98fac90452f876511fee8a35565a55dfb191f x
 F configure.ac 4cf9f60785143fa141b10962ccc885d973792e9a
 F contrib/sqlitecon.tcl 210a913ad63f9f991070821e599d600bd913e0ad
 F doc/lemon.html 334dbf6621b8fb8790297ec1abf3cfa4621709d1
@@ -78,9 +78,9 @@ F ext/fts3/README.content fdc666a70d5257a64fee209f97cf89e0e6e32b51
 F ext/fts3/README.syntax a19711dc5458c20734b8e485e75fb1981ec2427a
 F ext/fts3/README.tokenizers e0a8b81383ea60d0334d274fadf305ea14a8c314
 F ext/fts3/README.txt 8c18f41574404623b76917b9da66fcb0ab38328d
-F ext/fts3/fts3.c 3fe91e36a0304ad4b35020f0e22ff37e95873166
+F ext/fts3/fts3.c 41b1920b9a8657963f09cb93b208c2671c5568db
 F ext/fts3/fts3.h 3a10a0af180d502cecc50df77b1b22df142817fe
-F ext/fts3/fts3Int.h eb5f8029589f3d8f1dc7fd50c773326a640388b1
+F ext/fts3/fts3Int.h bdeb9015405e8facffb8fc7e09174521a2a780f4
 F ext/fts3/fts3_aux.c 5c211e17a64885faeb16b9ba7772f9d5445c2365
 F ext/fts3/fts3_expr.c 5165c365cb5a035f5be8bb296f7aa3211d43e4ac
 F ext/fts3/fts3_hash.c 29b986e43f4e9dd40110eafa377dc0d63c422c60
@@ -96,7 +96,7 @@ F ext/fts3/fts3_tokenizer.h 64c6ef6c5272c51ebe60fc607a896e84288fcbc3
 F ext/fts3/fts3_tokenizer1.c 5c98225a53705e5ee34824087478cf477bdb7004
 F ext/fts3/fts3_unicode.c 92391b4b4fb043564c6539ea9b8661e3bcba47b9
 F ext/fts3/fts3_unicode2.c 0113d3acf13429e6dc38e0647d1bc71211c31a4d
-F ext/fts3/fts3_write.c cdebe72171a217b1465032dec103f8d17f7dad4d
+F ext/fts3/fts3_write.c 74c00329006c3ed6325ba4e5ab7c9b5fc99c8934
 F ext/fts3/fts3speed.tcl b54caf6a18d38174f1a6e84219950d85e98bb1e9
 F ext/fts3/mkfts3amal.tcl 252ecb7fe6467854f2aa237bf2c390b74e71f100
 F ext/fts3/tool/fts3view.c 6cfc5b67a5f0e09c0d698f9fd012c784bfaa9197
@@ -120,7 +120,7 @@ F ext/misc/vfslog.c fe40fab5c077a40477f7e5eba994309ecac6cc95
 F ext/misc/vtshim.c babb0dc2bf116029e3e7c9a618b8a1377045303e
 F ext/misc/wholenumber.c 784b12543d60702ebdd47da936e278aa03076212
 F ext/rtree/README 6315c0d73ebf0ec40dedb5aa0e942bc8b54e3761
-F ext/rtree/rtree.c a4e18b2c150adad20aecbeb3408cd235a0a57441
+F ext/rtree/rtree.c 2d9f95da404d850474e628c720c5ce15d29b47de
 F ext/rtree/rtree.h 834dbcb82dc85b2481cde6a07cdadfddc99e9b9e
 F ext/rtree/rtree1.test cf679265ecafff494a768ac9c2f43a70915a6290
 F ext/rtree/rtree2.test acbb3a4ce0f4fbc2c304d2b4b784cfa161856bba
@@ -133,7 +133,8 @@ F ext/rtree/rtree8.test db79c812f9e4a11f9b1f3f9934007884610a713a
 F ext/rtree/rtree9.test d86ebf08ff6328895613ed577dd8a2a37c472c34
 F ext/rtree/rtreeA.test ace05e729a36e342d40cf94e9efc7b4723d9dcdf
 F ext/rtree/rtreeB.test 983e567b49b5dca165940f66b87e161aa30e82b2
-F ext/rtree/rtreeC.test 03975565f40a0bee165f613143e4dec716dd5a59
+F ext/rtree/rtreeC.test 16d7aa86ecb6a876d2a38cf590a1471a41b3a46d
+F ext/rtree/rtreeD.test 636630357638f5983701550b37f0f5867130d2ca
 F ext/rtree/rtree_perf.tcl 6c18c1f23cd48e0f948930c98dfdd37dfccb5195
 F ext/rtree/rtree_util.tcl 06aab2ed5b826545bf215fff90ecb9255a8647ea
 F ext/rtree/sqlite3rtree.h c34c1e41d1ab80bb8ad09aae402c9c956871a765
@@ -142,7 +143,7 @@ F ext/rtree/viewrtree.tcl eea6224b3553599ae665b239bd827e182b466024
 F install-sh 9d4de14ab9fb0facae2f48780b874848cbf2f895 x
 F ltmain.sh 3ff0879076df340d2e23ae905484d8c15d5fdea8
 F magic.txt f439556c5ce01ced70987e5ee86549a45165d9ff
-F main.mk 3ae543fa446525c1dec55f58de67f41b78651812
+F main.mk 4b30dd2a6cb441db688972496b45a6c3abef8b20
 F mkopcodec.awk c2ff431854d702cdd2d779c9c0d1f58fa16fa4ea
 F mkopcodeh.awk c6b3fa301db6ef7ac916b14c60868aeaec1337b5
 F mkso.sh fd21c06b063bb16a5d25deea1752c2da6ac3ed83
@@ -163,20 +164,20 @@ F src/auth.c 523da7fb4979469955d822ff9298352d6b31de34
 F src/backup.c a729e63cf5cd1829507cb7b8e89f99b95141bb53
 F src/bitvec.c 19a4ba637bd85f8f63fc8c9bae5ade9fb05ec1cb
 F src/btmutex.c 976f45a12e37293e32cae0281b15a21d48a8aaa7
-F src/btree.c 4d28fb15543f0e071b1780b2af8cd2ee489de32d
-F src/btree.h 9e0f97c01b972f779eb7655cfb4f8727fd6dc26f
+F src/btree.c 0d1be67448c45eccc40114556186397eb9da7f7d
+F src/btree.h 232836cb51753f2e96aa8ce0f052c6df850f76ba
 F src/btreeInt.h 0be66063468a520e4d66b80c7a1dc26d04ee6ea4
-F src/build.c 0d50ef95aad63f4c4fc47f3fa2670d4557c45db0
+F src/build.c e120a3693ac78ab3e74048205f07a3a522d9b982
 F src/callback.c 174e3c8656bc29f91d710ab61550d16eea34be98
 F src/complete.c dc1d136c0feee03c2f7550bafc0d29075e36deac
 F src/ctime.c 0231df905e2c4abba4483ee18ffc05adc321df2a
 F src/date.c 593c744b2623971e45affd0bde347631bdfa4625
 F src/delete.c cdd57149543bb28304d8f717c243f2a86b1fc280
-F src/expr.c 014b8087a15c4c314bdd798cb1cb0b32693f8b40
+F src/expr.c da2b3cb41081af6b56e95e7c9e95949564ce2e21
 F src/fault.c 160a0c015b6c2629d3899ed2daf63d75754a32bb
 F src/fkey.c 5269ef07b100763134f71b889327c333bd0989cf
 F src/func.c 2945bb2c4cdc0ac43733046285a4434310be1811
-F src/global.c 1d7bb7ea8254ae6a68ed9bfaf65fcb3d1690b486
+F src/global.c deadd872189b92aca4ee2566332a86315839f811
 F src/hash.c d139319967164f139c8d1bb8a11b14db9c4ba3cd
 F src/hash.h 8890a25af81fb85a9ad7790d32eedab4b994da22
 F src/hwtime.h d32741c8f4df852c7d959236615444e2b1063b08
@@ -185,13 +186,13 @@ F src/journal.c b4124532212b6952f42eb2c12fa3c25701d8ba8d
 F src/legacy.c 0df0b1550b9cc1f58229644735e317ac89131f12
 F src/lempar.c cdf0a000315332fc9b50b62f3b5e22e080a0952b
 F src/loadext.c 867c7b330b740c6c917af9956b13b81d0a048303
-F src/main.c e054917b1beb3081b0f23e8bdd3d6c0e12933dd3
+F src/main.c fcceb01d74a79c2d7984f33545b35b06da3bb1e8
 F src/malloc.c 0203ebce9152c6a0e5de520140b8ba65187350be
 F src/mem0.c 6a55ebe57c46ca1a7d98da93aaa07f99f1059645
 F src/mem1.c c0c990fcaddff810ea277b4fb5d9138603dd5d4b
 F src/mem2.c dce31758da87ec2cfa52ba4c5df1aed6e07d8e8f
 F src/mem3.c 61c9d47b792908c532ca3a62b999cf21795c6534
-F src/mem5.c aeb019f271ea53de83d651ec526877e6ba863450
+F src/mem5.c 74670012946c4adc8a6ad84d03acc80959c3e529
 F src/memjournal.c 0683aac6cab6ec2b5374c0db37c0deb2436a3785
 F src/mutex.c d3b66a569368015e0fcb1ac15f81c119f504d3bc
 F src/mutex.h 5bc526e19dccc412b7ff04642f6fdad3fdfdabea
@@ -202,31 +203,31 @@ F src/notify.c 976dd0f6171d4588e89e874fcc765e92914b6d30
 F src/os.c 1b147e4cf7cc39e618115c14a086aed44bc91ace
 F src/os.h 4a46270a64e9193af4a0aaa3bc2c66dc07c29b3f
 F src/os_common.h 92815ed65f805560b66166e3583470ff94478f04
-F src/os_unix.c 18f7f95dc6bcb9cf4d4a238d8e2de96611bc2ae5
-F src/os_win.c e71678ac927d0a0fb11d993db20a9748eabf808e
-F src/pager.c 97a8908bf4e6e7c3adea09d3597cfa48ae33ab4e
+F src/os_unix.c ae4b5240af4619d711301d7992396e182585269f
+F src/os_win.c 8245fe9184300e641d02e29a8ca95cefe0cb0fd0
+F src/pager.c ab62a24218d87dda1be641f6c5ad291bff78fd94
 F src/pager.h ffd5607f7b3e4590b415b007a4382f693334d428
-F src/parse.y 2613ca5d609c2f3d71dd297351f010bcec16e1e0
+F src/parse.y 22d6a074e5f5a7258947a1dc55a9bf946b765dd0
 F src/pcache.c d8eafac28290d4bb80332005435db44991d07fc2
 F src/pcache.h a5e4f5d9f5d592051d91212c5949517971ae6222
 F src/pcache1.c 102e6f5a2fbc646154463eb856d1fd716867b64c
-F src/pragma.c a46ee83671f5c95f53d2ceeb5e1a818d7b1df99a
+F src/pragma.c 10f169b9650f0930a7a6df67e1387a4c2c449f38
 F src/prepare.c 677521ab7132615a8a26107a1d1c3132f44ae337
-F src/printf.c 85d07756e45d7496d19439dcae3e6e9e0090f269
+F src/printf.c e5a0005f8b3de21f85da6a709d2fbee76775bf4b
 F src/random.c d10c1f85b6709ca97278428fd5db5bbb9c74eece
 F src/resolve.c 273d5f47c4e2c05b2d3d2bffeda939551ab59e66
 F src/rowset.c 64655f1a627c9c212d9ab497899e7424a34222e0
-F src/select.c 0adf172d33cc610ff5ffe26edfd2ba67c3551655
-F src/shell.c bab4de12b441369491812ecc93212ff4deda68fa
-F src/sqlite.h.in a2ef671f92747a5a1c8a47bad5c585a8dd9eca80
+F src/select.c 20055cf917222e660c4222fea306bd13a0623caa
+F src/shell.c b44c3f17f0bf41b3431e9cc171706251156ae85f
+F src/sqlite.h.in 81221c50addbf698c3247154d92efd1095bfd885
 F src/sqlite3.rc 11094cc6a157a028b301a9f06b3d03089ea37c3e
 F src/sqlite3ext.h 886f5a34de171002ad46fae8c36a7d8051c190fc
-F src/sqliteInt.h fa7161b3de18a9c355d4148233f3563c92311fcc
+F src/sqliteInt.h 533154bf9d8401ff3e6f8030f4373774c0a6ad41
 F src/sqliteLimit.h 164b0e6749d31e0daa1a4589a169d31c0dec7b3d
 F src/status.c 7ac05a5c7017d0b9f0b4bcd701228b784f987158
 F src/table.c 2cd62736f845d82200acfa1287e33feb3c15d62e
 F src/tclsqlite.c e87c99e28a145943666b51b212dacae35fcea0bd
-F src/test1.c 2401eee14a4309a7cfe2aeb2f30ad517a1d9c299
+F src/test1.c 0cd73ae82fdf7add76ca603e3575380ae7539ae2
 F src/test2.c 7355101c085304b90024f2261e056cdff13c6c35
 F src/test3.c 1c0e5d6f080b8e33c1ce8b3078e7013fdbcd560c
 F src/test4.c 9b32d22f5f150abe23c1830e2057c4037c45b3df
@@ -239,7 +240,7 @@ F src/test_async.c 21e11293a2f72080eda70e1124e9102044531cd8
 F src/test_autoext.c dea8a01a7153b9adc97bd26161e4226329546e12
 F src/test_backup.c 3875e899222b651e18b662f86e0e50daa946344e
 F src/test_btree.c 5b89601dcb42a33ba8b820a6b763cc9cb48bac16
-F src/test_config.c 0336e0bdbe541b4af89d7e3dd0656e8e6b51e585
+F src/test_config.c ebd0a42983b696f2b121515d577753cf2afdc9b0
 F src/test_demovfs.c 69b2085076654ebc18014cbc6386f04409c959a9
 F src/test_devsym.c e7498904e72ba7491d142d5c83b476c4e76993bc
 F src/test_fs.c ced436e3d4b8e4681328409b8081051ce614e28f
@@ -250,7 +251,7 @@ F src/test_intarray.c 87847c71c3c36889c0bcc9c4baf9d31881665d61
 F src/test_intarray.h 2ece66438cfd177b78d1bfda7a4180cd3a10844d
 F src/test_journal.c f5c0a05b7b3d5930db769b5ee6c3766dc2221a64
 F src/test_loadext.c a5251f956ab6af21e138dc1f9c0399394a510cb4
-F src/test_malloc.c 1ff5b1243d96124c9a180f3b89424820a1f337f3
+F src/test_malloc.c 27047a841f5bff1cb638123806a2c30714771307
 F src/test_multiplex.c 9f304bf04170c91c0318238d512df2da039eb1c8
 F src/test_multiplex.h 110a8c4d356e0aa464ca8730375608a9a0b61ae1
 F src/test_mutex.c 293042d623ebba969160f471a82aa1551626454f
@@ -265,33 +266,34 @@ F src/test_server.c a2615049954cbb9cfb4a62e18e2f0616e4dc38fe
 F src/test_sqllog.c c1c1bbedbcaf82b93d83e4f9dd990e62476a680e
 F src/test_stat.c 9898687a6c2beca733b0dd6fe19163d987826d31
 F src/test_superlock.c 2b97936ca127d13962c3605dbc9a4ef269c424cd
-F src/test_syscall.c 16dbe79fb320fadb5acd7a0a59f49e52ab2d2091
+F src/test_syscall.c 2e21ca7f7dc54a028f1967b63f1e76155c356f9b
 F src/test_tclvar.c f4dc67d5f780707210d6bb0eb6016a431c04c7fa
 F src/test_thread.c 1e133a40b50e9c035b00174035b846e7eef481cb
 F src/test_vfs.c e72f555ef7a59080f898fcf1a233deb9eb704ea9
 F src/test_vfstrace.c 3a0ab304682fecbceb689e7d9b904211fde11d78
 F src/test_wsd.c 41cadfd9d97fe8e3e4e44f61a4a8ccd6f7ca8fe9
+F src/threads.c b8e7232f2b9c9d148d6886117160de394d172f85
 F src/tokenize.c 6da2de6e12218ccb0aea5184b56727d011f4bee7
-F src/trigger.c a80036fcbd992729adc7cd34a875d59a71fa10cc
+F src/trigger.c 66f3470b03b52b395e839155786966e3e037fddb
 F src/update.c 5b3e74a03b3811e586b4f2b4cbd7c49f01c93115
 F src/utf.c 6dc9ec9f1b3db43ae8ba0365377f11df1ee4c01c
 F src/util.c c46c90459ef9bdc0c6c73803cf4c55425b4771cf
 F src/vacuum.c 3728d74919d4fb1356f9e9a13e27773db60b7179
-F src/vdbe.c 5f0fffa9bf49a90c05dc3d46d8217603fd0ee00e
-F src/vdbe.h d189f92468a17a6f04daeec9df3b767f50557b21
-F src/vdbeInt.h e54fc4f289fce48e81b3371128446033d097733b
+F src/vdbe.c 9f3d1b35b5fe8c7f3a4f734bd524d0df844a2576
+F src/vdbe.h 394464909ed682334aa3d5831aae0c2fe2abef94
+F src/vdbeInt.h ba1069627d0ab75e9ddb8f9c10958b86cdbd333d
 F src/vdbeapi.c 0ed6053f947edd0b30f64ce5aeb811872a3450a4
-F src/vdbeaux.c e45e3f9daf38c5be3fd39e9aacc1c9066af57a06
-F src/vdbeblob.c d939997de046b8fcc607cfee4248f3d33dbcca50
+F src/vdbeaux.c d8dc38965507a34b0e150c0d7fc82b02f8cf25ea
+F src/vdbeblob.c 15377abfb59251bccedd5a9c7d014a895f0c04aa
 F src/vdbemem.c 6fc77594c60f6155404f3f8d71bf36d1fdeb4447
-F src/vdbesort.c 46801acb342e5e4c07ba1777fe58880c143abb59
+F src/vdbesort.c 07c29a5a61e041eeb1c366eefef9e99dfe5e2174
 F src/vdbetrace.c 6f52bc0c51e144b7efdcfb2a8f771167a8816767
 F src/vtab.c 21b932841e51ebd7d075e2d0ad1415dce8d2d5fd
 F src/wal.c 76e7fc6de229bea8b30bb2539110f03a494dc3a8
 F src/wal.h df01efe09c5cb8c8e391ff1715cca294f89668a4
 F src/walker.c 11edb74d587bc87b33ca96a5173e3ec1b8389e45
-F src/where.c 95d30485879122acc5284d4523e01399b23b6148
-F src/whereInt.h 921f935af8b684ffb49705610bda7284db1db138
+F src/where.c 70eb10da08cebbd6a576ced18edb7c8f79d41597
+F src/whereInt.h 2564055b440e44ebec8b47f237bbccae6719b7af
 F test/8_3_names.test ebbb5cd36741350040fd28b432ceadf495be25b2
 F test/aggerror.test a867e273ef9e3d7919f03ef4f0e8c0d2767944f2
 F test/aggnested.test 45c0201e28045ad38a530b5a144b73cd4aa2cfd6
@@ -402,9 +404,9 @@ F test/corruptC.test 02405cf7ed0c1e989060e1aab6d02ffbc3906fbb
 F test/corruptD.test b3c205fac7952b1de645ce44bb02335cd9e3e040
 F test/corruptE.test 193b4ca4e927e77c1d5f4f56203ddc998432a7ee
 F test/corruptF.test be9fde98e4c93648f1ba52b74e5318edc8f59fe4
-F test/corruptG.test 58ec333a01997fe655e34e5bea52b7a2a6b9704d
+F test/corruptG.test 1ab3bf97ee7bdba70e0ff3ba2320657df55d1804
 F test/corruptH.test 88ed71a086e13591c917aac6de32750e7c7281cb
-F test/corruptI.test 88886ec9cd1bdba835263566bbf60ee009c6ea09
+F test/corruptI.test b3e4203d420490fc3d3062711597bc1dea06a789
 F test/count.test 42a251178e32f617eda33f76236a7f79825a50b5
 F test/coveridxscan.test cdb47d01acc4a634a34fd25abe85189e0d0f1e62
 F test/crash.test fb9dc4a02dcba30d4aa5c2c226f98b220b2b959f
@@ -430,7 +432,7 @@ F test/descidx1.test 6d03b44c8538fe0eb4924e19fba10cdd8f3c9240
 F test/descidx2.test 9f1a0c83fd57f8667c82310ca21b30a350888b5d
 F test/descidx3.test 09ddbe3f5295f482d2f8b687cf6db8bad7acd9a2
 F test/diskfull.test 106391384780753ea6896b7b4f005d10e9866b6e
-F test/distinct.test c7b194ef95dbddb32d77acbbab2e023c6eed0cb2
+F test/distinct.test 086e70c765f172e8974e9f83b9ac5ca03c154e77
 F test/distinctagg.test 1a6ef9c87a58669438fc771450d7a72577417376
 F test/e_createtable.test ee95d48664503d40f6cc9ef4a7d03216188e2ada
 F test/e_delete.test d5186e2f5478b659f16a2c8b66c09892823e542a
@@ -522,7 +524,7 @@ F test/fts3ak.test bd14deafe9d1586e8e9bf032411026ac4f8c925d
 F test/fts3al.test 07d64326e79bbdbab20ee87fc3328fbf01641c9f
 F test/fts3am.test 218aa6ba0dfc50c7c16b2022aac5c6be593d08d8
 F test/fts3an.test a49ccadc07a2f7d646ec1b81bc09da2d85a85b18
-F test/fts3ao.test 71b0675e3df5c512a5a03daaa95ee1916de23dda
+F test/fts3ao.test 3e4e3d5e75c076520341d0bdf4eb17c00e8cbde2
 F test/fts3atoken.test fca30fd86db9241d571c637751e9a8a2f50f1451
 F test/fts3auto.test b981fea19b132b4e6878f50d7c1f369b28f68eb9
 F test/fts3aux1.test f8f287a4a73f381f8fa15b6a70f36245f903d221
@@ -534,7 +536,7 @@ F test/fts3conf.test ee8500c86dd58ec075e8831a1e216a79989436de
 F test/fts3corrupt.test 2710b77983cc7789295ddbffea52c1d3b7506dbb
 F test/fts3corrupt2.test 6d96efae2f8a6af3eeaf283aba437e6d0e5447ba
 F test/fts3cov.test e0fb00d8b715ddae4a94c305992dfc3ef70353d7
-F test/fts3d.test c8a193513a269ec4c205ca09645e26e0bc71b860
+F test/fts3d.test 597b0b76e41f0d672e2731c4d7b631d628efd13f
 F test/fts3defer.test 0be4440b73a2e651fc1e472066686d6ada4b9963
 F test/fts3defer2.test a3b6cbeabaf28c9398652a4d101ea224d9358479
 F test/fts3defer3.test dd53fc13223c6d8264a98244e9b19abd35ed71cd
@@ -592,7 +594,7 @@ F test/icu.test 70df4faca133254c042d02ae342c0a141f2663f4
 F test/in.test 047c4671328e9032ab95666a67021adbbd36e98e
 F test/in2.test 5d4c61d17493c832f7d2d32bef785119e87bde75
 F test/in3.test 3cbf58c87f4052cee3a58b37b6389777505aa0c0
-F test/in4.test 64f3cc1acde1b9161ccdd8e5bde3daefdb5b2617
+F test/in4.test 41c1c031aa46b1eb4411df2687ed2ed498da23b5
 F test/in5.test 99f9a40af01711b06d2d614ecfe96129f334fba3
 F test/incrblob.test e81846d214f3637622620fbde7cd526781cfe328
 F test/incrblob2.test bf4d549aa4a466d7fbe3e3a3693d3861263d5600
@@ -647,7 +649,7 @@ F test/lastinsert.test 42e948fd6442f07d60acbd15d33fb86473e0ef63
 F test/laststmtchanges.test ae613f53819206b3222771828d024154d51db200
 F test/like.test e191e536d0fcd722a6b965e7cd1ee0bfd12a5991
 F test/like2.test 3b2ee13149ba4a8a60b59756f4e5d345573852da
-F test/limit.test cc0ab63385239b63c72452b0e93700bf5e8f0b99
+F test/limit.test 3d7df19c35ac672a11f7de406cd3205d592babbb
 F test/loadext.test 648cb95f324d1775c54a55c12271b2d1156b633b
 F test/loadext2.test 0408380b57adca04004247179837a18e866a74f7
 F test/lock.test 87af515b0c4cf928576d0f89946d67d7c265dfb4
@@ -661,7 +663,7 @@ F test/lock_common.tcl 0c270b121d40959fa2f3add382200c27045b3d95
 F test/lookaside.test 93f07bac140c5bb1d49f3892d2684decafdc7af2
 F test/main.test 39c4bb8a157f57298ed1659d6df89d9f35aaf2c8
 F test/make-where7.tcl 05c16b5d4f5d6512881dfec560cb793915932ef9
-F test/malloc.test fd368e31fe98d4779ed80442f311ed9f03bcd1f7
+F test/malloc.test 26ae08a09cc15a98d147ee63925e3a66048e71c9
 F test/malloc3.test e3b32c724b5a124b57cb0ed177f675249ad0c66a
 F test/malloc4.test 957337613002b7058a85116493a262f679f3a261
 F test/malloc5.test fafce0aa9157060445cd1a56ad50fc79d82f28c3
@@ -669,7 +671,7 @@ F test/malloc6.test 2f039d9821927eacae43e1831f815e157659a151
 F test/malloc7.test 7c68a32942858bc715284856c5507446bba88c3a
 F test/malloc8.test 9b7a3f8cb9cf0b12fff566e80a980b1767bd961d
 F test/malloc9.test 2307c6ee3703b0a21391f3ea92388b4b73f9105e
-F test/mallocA.test 1ba0367fb5434e7bc2fa4afcb30b14174d91b160
+F test/mallocA.test c049224adeb0244b8f6eb770c1fa6ac40f9b3518
 F test/mallocAll.test 98f1be74bc9f49a858bc4f361fc58e26486798be
 F test/mallocB.test bc475ab850cda896142ab935bbfbc74c24e51ed6
 F test/mallocC.test 3dffe16532f109293ce1ccecd0c31dca55ef08c4
@@ -721,7 +723,8 @@ F test/orderby1.test 9b524aff9147288da43a6d7ddfdcff47fa2303c6
 F test/orderby2.test bc11009f7cd99d96b1b11e57b199b00633eb5b04
 F test/orderby3.test 8619d06a3debdcd80a27c0fdea5c40b468854b99
 F test/orderby4.test 4d39bfbaaa3ae64d026ca2ff166353d2edca4ba4
-F test/orderby5.test 0eb82d5890c3f3d0563966560cfdc984ea69e30c
+F test/orderby5.test 2490183fef54417209d1df253633a605d46bd350
+F test/orderby6.test 8b38138ab0972588240b3fca0985d2e400432859
 F test/oserror.test 50417780d0e0d7cd23cf12a8277bb44024765df3
 F test/pager1.test 1acbdb14c5952a72dd43129cabdbf69aaa3ed1fa
 F test/pager2.test 67b8f40ae98112bcdba1f2b2d03ea83266418c71
@@ -735,7 +738,7 @@ F test/pagesize.test 1dd51367e752e742f58e861e65ed7390603827a0
 F test/pcache.test b09104b03160aca0d968d99e8cd2c5b1921a993d
 F test/pcache2.test a83efe2dec0d392f814bfc998def1d1833942025
 F test/percentile.test b98fc868d71eb5619d42a1702e9ab91718cbed54
-F test/permutations.test 40add071ba71aefe1c04f5845308cf46f7de8d04
+F test/permutations.test a214a42b4767bbbc7cd0fd965ea6198044ab414d
 F test/pragma.test adb21a90875bc54a880fa939c4d7c46598905aa0
 F test/pragma2.test aea7b3d82c76034a2df2b38a13745172ddc0bc13
 F test/printf.test ec9870c4dce8686a37818e0bf1aba6e6a1863552
@@ -810,11 +813,13 @@ F test/shell5.test bb755ea9144b8078a752fc56223582627070b5f1
 F test/shortread1.test bb591ef20f0fd9ed26d0d12e80eee6d7ac8897a3
 F test/shrink.test 8c70f62b6e8eb4d54533de6d65bd06b1b9a17868
 F test/sidedelete.test f0ad71abe6233e3b153100f3b8d679b19a488329
-F test/skipscan1.test 8c777ffd9dad6ee6d2568160cb2158f0b5cd9dd2
+F test/skipscan1.test bed8cbe9d554c8c27afb6c88500f704c86a9196f
 F test/skipscan2.test 5a4db0799c338ddbacb154aaa5589c0254b36a8d
 F test/soak.test 0b5b6375c9f4110c828070b826b3b4b0bb65cd5f
 F test/softheap1.test 40562fe6cac6d9827b7b42b86d45aedf12c15e24
-F test/sort.test 0e4456e729e5a92a625907c63dcdedfbe72c5dc5
+F test/sort.test 79dc647c4e9b123a64e57b7080b7f9a2df43f87a
+F test/sort2.test 21cd865e31adecdc8fc81c8d95431e629676a8d8
+F test/sort3.test c3f88d233452a129de519de311d109a0ad0da0af
 F test/speed1.test f2974a91d79f58507ada01864c0e323093065452
 F test/speed1p.explain d841e650a04728b39e6740296b852dccdca9b2cb
 F test/speed1p.test b180e98609c7677382cf618c0ec9b69f789033a8
@@ -823,7 +828,7 @@ F test/speed3.test d32043614c08c53eafdc80f33191d5bd9b920523
 F test/speed4.test abc0ad3399dcf9703abed2fff8705e4f8e416715
 F test/speed4p.explain 6b5f104ebeb34a038b2f714150f51d01143e59aa
 F test/speed4p.test 0e51908951677de5a969b723e03a27a1c45db38b
-F test/speedtest1.c 1603da7b4897716f9df15bd71b0310f56ec3181e
+F test/speedtest1.c 90446861e566a9965a8d005381a3c964ff333646
 F test/spellfix.test 61309f5efbec53603b3f86457d34a504f80abafe
 F test/sqllimits1.test b1aae27cc98eceb845e7f7adf918561256e31298
 F test/stat.test 76fd746b85459e812a0193410fb599f0531f22de
@@ -834,7 +839,7 @@ F test/subselect.test d24fd8757daf97dafd2e889c73ea4c4272dcf4e4
 F test/substr.test 18f57c4ca8a598805c4d64e304c418734d843c1a
 F test/superlock.test 1cde669f68d2dd37d6c9bd35eee1d95491ae3fc2
 F test/sync.test a34cd43e98b7fb84eabbf38f7ed8f7349b3f3d85
-F test/syscall.test a653783d985108c4912cc64d341ffbbb55ad2806
+F test/syscall.test d2fdaad713f103ac611fe7ef9b724c7b69f8149c
 F test/sysfault.test fa776e60bf46bdd3ae69f0b73e46ee3977a58ae6
 F test/table.test 580d23530187026d4502fae74a490f0408cf2cc7
 F test/tableapi.test 2674633fa95d80da917571ebdd759a14d9819126
@@ -843,7 +848,7 @@ F test/tclsqlite.test 37a61c2da7e3bfe3b8c1a2867199f6b860df5d43
 F test/tempdb.test 19d0f66e2e3eeffd68661a11c83ba5e6ace9128c
 F test/temptable.test d2c9b87a54147161bcd1822e30c1d1cd891e5b30
 F test/temptrigger.test 8ec228b0db5d7ebc4ee9b458fc28cb9e7873f5e1
-F test/tester.tcl f31bea1483ea1d39620f982130026e76f872d744
+F test/tester.tcl bc0889a2f86d9c17307992ca1e70391794780265
 F test/thread001.test 9f22fd3525a307ff42a326b6bc7b0465be1745a5
 F test/thread002.test e630504f8a06c00bf8bbe68528774dd96aeb2e58
 F test/thread003.test ee4c9efc3b86a6a2767516a37bd64251272560a7
@@ -890,6 +895,7 @@ F test/tkt-94c04eaadb.test f738c57c7f68ab8be1c054415af7774617cb6223
 F test/tkt-9d68c883.test 458f7d82a523d7644b54b497c986378a7d8c8b67
 F test/tkt-9f2eb3abac.test 85bc63e749f050e6a61c8f9207f1eee65c9d3395
 F test/tkt-a7b7803e.test 159ef554234fa1f9fb318c751b284bd1cf858da4
+F test/tkt-a8a0d2996a.test eb597379dbcefa24765763d7f682c00cb5924fa9
 F test/tkt-b1d3a2e531.test 8f7576e41ca179289ee1a8fee28386fd8e4b0550
 F test/tkt-b351d95f9.test d14a503c414c5c58fdde3e80f9a3cfef986498c0
 F test/tkt-b72787b1.test a95e8cdad0b98af1853ac7f0afd4ab27b77bf5f3
@@ -1046,13 +1052,14 @@ F test/vtabE.test 7c4693638d7797ce2eda17af74292b97e705cc61
 F test/vtabF.test fd5ad376f5a34fe0891df1f3cddb4fe7c3eb077e
 F test/vtab_alter.test 9e374885248f69e251bdaacf480b04a197f125e5
 F test/vtab_err.test 0d4d8eb4def1d053ac7c5050df3024fd47a3fbd8
-F test/vtab_shared.test 6acafaae7126c9f49be72c2f57eb8bef3024f1cb
-F test/wal.test 40073e54359d43354925b2b700b7eebd5e207285
+F test/vtab_shared.test ea8778d5b0df200adef2ca7c00c3c37d4375f772
+F test/wal.test 885f32b2b390b30b4aa3dbb0e568f8f78d40f5cc
 F test/wal2.test a8e3963abf6b232cf0b852b09b53665ef34007af
 F test/wal3.test b22eb662bcbc148c5f6d956eaf94b047f7afe9c0
 F test/wal4.test 4744e155cd6299c6bd99d3eab1c82f77db9cdb3c
 F test/wal5.test 8f888b50f66b78821e61ed0e233ded5de378224b
 F test/wal6.test 527581f5527bf9c24394991e2be83000aace5f9e
+F test/wal64k.test 163655ecd2cb8afef4737cac2a40fdd2eeaf20b8
 F test/wal7.test 2ae8f427d240099cc4b2dfef63cff44e2a68a1bd
 F test/wal8.test 75c42e1bc4545c277fed212f8fc9b7723cd02216
 F test/wal9.test 378e76a9ad09cd9bee06c172ad3547b0129a6750
@@ -1088,14 +1095,15 @@ F test/whereC.test d6f4ecd4fa2d9429681a5b22a25d2bda8e86ab8a
 F test/whereD.test 6c2feb79ef1f68381b07f39017fe5f9b96da8d62
 F test/whereE.test b3a055eef928c992b0a33198a7b8dc10eea5ad2f
 F test/whereF.test 5b2ba0dbe8074aa13e416b37c753991f0a2492d7
-F test/whereG.test 2a3d5181decc801b36600fa1c40b0dad2ccc267f
+F test/whereG.test 2533b72ed4a31fd1687230a499b557b911525344
+F test/whereH.test e4b07f7a3c2f5d31195cd33710054c78667573b2
 F test/wherelimit.test 5e9fd41e79bb2b2d588ed999d641d9c965619b31
 F test/wild001.test bca33f499866f04c24510d74baf1e578d4e44b1c
 F test/win32heap.test ea19770974795cff26e11575e12d422dbd16893c
 F test/win32lock.test 7a6bd73a5dcdee39b5bb93e92395e1773a194361
 F test/win32longpath.test 169c75a3b2e43481f4a62122510210c67b08f26d
 F test/with1.test 268081a6b14817a262ced4d0ee34d4d2a1dd2068
-F test/with2.test 2fe78fcd8deef2a0f9cfc49bfc755911d0b3fd64
+F test/with2.test ee227a663586aa09771cafd4fa269c5217eaf775
 F test/withM.test e97f2a8c506ab3ea9eab94e6f6072f6cc924c991
 F test/without_rowid1.test e00a0a9dc9f0be651f011d61e8a32b7add5afb30
 F test/without_rowid2.test af260339f79d13cb220288b67cd287fbcf81ad99
@@ -1117,14 +1125,14 @@ F tool/genfkey.test 4196a8928b78f51d54ef58e99e99401ab2f0a7e5
 F tool/getlock.c f4c39b651370156cae979501a7b156bdba50e7ce
 F tool/lemon.c 07aba6270d5a5016ba8107b09e431eea4ecdc123
 F tool/lempar.c 01ca97f87610d1dac6d8cd96ab109ab1130e76dc
-F tool/logest.c 7ad625cac3d54012b27d468b7af6612f78b9ba75
+F tool/logest.c 388c318c7ac8b52b7c08ca1e2de0f4ca9a8f7e81
 F tool/mkautoconfamal.sh f8d8dbf7d62f409ebed5134998bf5b51d7266383
 F tool/mkkeywordhash.c c9e05e4a7bcab8fab9f583d5b321fb72f565ad97
 F tool/mkopts.tcl 66ac10d240cc6e86abd37dc908d50382f84ff46e
 F tool/mkpragmatab.tcl 78a77b2c554d534c6f2dc903130186ed15715460
 F tool/mkspeedsql.tcl a1a334d288f7adfe6e996f2e712becf076745c97
-F tool/mksqlite3c-noext.tcl 8bce31074e4cbe631bb7676526a048335f4c9f02
-F tool/mksqlite3c.tcl ed5b4e9ca8bf209ff401059a16362f37710fd8b8
+F tool/mksqlite3c-noext.tcl 752f1a9d3287f6c0ef5738b1c4add0b96fbe0854
+F tool/mksqlite3c.tcl 8da823522f27608494997e1dba19cd426572ba80
 F tool/mksqlite3h.tcl ba24038056f51fde07c0079c41885ab85e2cff12
 F tool/mksqlite3internalh.tcl 3dca7bb5374cee003379b8cbac73714f610ef795
 F tool/mkvsix.tcl 6477fb9dab838b7eea1eed50658ff1cda04850b5
@@ -1155,10 +1163,10 @@ F tool/vdbe_profile.tcl 67746953071a9f8f2f668b73fe899074e2c6d8c1
 F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh d1a6de74685f360ab718efda6265994b99bbea01
 F tool/win/sqlite.vsix 030f3eeaf2cb811a3692ab9c14d021a75ce41fff
-P ba39df9d4f7ffc6475ae0dc794f7d3f58c486de8
-R f73df97bd275791734e233575a443767
-T +bgcolor * #d0c0ff
-T +sym-release *
-T +sym-version-3.8.4 *
-U drh
-Z 82f901d4413784b1ea9af3cba9303801
+P e54dded2012f0ab486ee138e9bd57c528af33980
+R 020c9d4d2bbea35c99aea5cfddab0eac
+T *branch * threads-experimental
+T *sym-threads-experimental *
+T -sym-threads *
+U dan
+Z 16c0542d21b377d284993b464ea194ff
@@ -1 +1 @@
-530a1ee7dc2435f80960ce4710a3c2d2bfaaccc5
+cbfc0f6d49b6607bb4eb45bfe4c258e39ac27403
@@ -746,20 +746,32 @@ static int btreeRestoreCursorPosition(BtCursor *pCur){
 ** at is deleted out from under them.
 **
 ** This routine returns an error code if something goes wrong.  The
-** integer *pHasMoved is set to one if the cursor has moved and 0 if not.
+** integer *pHasMoved is set as follows:
+**
+**    0:   The cursor is unchanged
+**    1:   The cursor is still pointing at the same row, but the pointers
+**         returned by sqlite3BtreeKeyFetch() or sqlite3BtreeDataFetch()
+**         might now be invalid because of a balance() or other change to the
+**         b-tree.
+**    2:   The cursor is no longer pointing to the row.  The row might have
+**         been deleted out from under the cursor.
 */
 int sqlite3BtreeCursorHasMoved(BtCursor *pCur, int *pHasMoved){
  int rc;

+  if( pCur->eState==CURSOR_VALID ){
+    *pHasMoved = 0;
+    return SQLITE_OK;
+  }
  rc = restoreCursorPosition(pCur);
  if( rc ){
-    *pHasMoved = 1;
+    *pHasMoved = 2;
    return rc;
  }
  if( pCur->eState!=CURSOR_VALID || NEVER(pCur->skipNext!=0) ){
-    *pHasMoved = 1;
+    *pHasMoved = 2;
  }else{
-    *pHasMoved = 0;
+    *pHasMoved = 1;
  }
  return SQLITE_OK;
 }
@@ -2161,6 +2173,7 @@ int sqlite3BtreeSetCacheSize(Btree *p, int mxPage){
  return SQLITE_OK;
 }

+#if SQLITE_MAX_MMAP_SIZE>0
 /*
 ** Change the limit on the amount of the database file that may be
 ** memory mapped.
@@ -2173,6 +2186,7 @@ int sqlite3BtreeSetMmapLimit(Btree *p, sqlite3_int64 szMmap){
  sqlite3BtreeLeave(p);
  return SQLITE_OK;
 }
+#endif /* SQLITE_MAX_MMAP_SIZE>0 */

 /*
 ** Change the way data is synced to disk in order to increase or decrease
@@ -4186,10 +4200,13 @@ static const void *fetchPayload(
  assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
  assert( cursorHoldsMutex(pCur) );
  assert( pCur->aiIdx[pCur->iPage]<pCur->apPage[pCur->iPage]->nCell );
+  assert( pCur->info.nSize>0 );
+#if 0
  if( pCur->info.nSize==0 ){
    btreeParseCell(pCur->apPage[pCur->iPage], pCur->aiIdx[pCur->iPage],
                   &pCur->info);
  }
+#endif
  *pAmt = pCur->info.nLocal;
  return (void*)(pCur->info.pCell + pCur->info.nHeader);
 }
@@ -4571,6 +4588,7 @@ int sqlite3BtreeMovetoUnpacked(

  if( pIdxKey ){
    xRecordCompare = sqlite3VdbeFindCompare(pIdxKey);
+    pIdxKey->errCode = 0;
    assert( pIdxKey->default_rc==1 
         || pIdxKey->default_rc==0 
         || pIdxKey->default_rc==-1
@@ -4694,6 +4712,10 @@ int sqlite3BtreeMovetoUnpacked(
          c = xRecordCompare(nCell, pCellKey, pIdxKey, 0);
          sqlite3_free(pCellKey);
        }
+        assert( 
+            (pIdxKey->errCode!=SQLITE_CORRUPT || c==0)
+         && (pIdxKey->errCode!=SQLITE_NOMEM || !pCur->pBtree->db->mallocFailed)
+        );
        if( c<0 ){
          lwr = idx+1;
        }else if( c>0 ){
@@ -4703,6 +4725,7 @@ int sqlite3BtreeMovetoUnpacked(
          *pRes = 0;
          rc = SQLITE_OK;
          pCur->aiIdx[pCur->iPage] = (u16)idx;
+          if( pIdxKey->errCode ) rc = SQLITE_CORRUPT;
          goto moveto_finish;
        }
        if( lwr>upr ) break;
@@ -7423,6 +7446,15 @@ int sqlite3BtreeClearTable(Btree *p, int iTable, int *pnChange){
  return rc;
 }

+/*
+** Delete all information from the single table that pCur is open on.
+**
+** This routine only work for pCur on an ephemeral table.
+*/
+int sqlite3BtreeClearTableOfCursor(BtCursor *pCur){
+  return sqlite3BtreeClearTable(pCur->pBtree, pCur->pgnoRoot, 0);
+}
+
 /*
 ** Erase all information in a table and add the root of the table to
 ** the freelist.  Except, the root of the principle table (the one on
@@ -63,7 +63,9 @@ int sqlite3BtreeOpen(

 int sqlite3BtreeClose(Btree*);
 int sqlite3BtreeSetCacheSize(Btree*,int);
-int sqlite3BtreeSetMmapLimit(Btree*,sqlite3_int64);
+#if SQLITE_MAX_MMAP_SIZE>0
+  int sqlite3BtreeSetMmapLimit(Btree*,sqlite3_int64);
+#endif
 int sqlite3BtreeSetPagerFlags(Btree*,unsigned);
 int sqlite3BtreeSyncDisabled(Btree*);
 int sqlite3BtreeSetPageSize(Btree *p, int nPagesize, int nReserve, int eFix);
@@ -113,6 +115,7 @@ int sqlite3BtreeIncrVacuum(Btree *);

 int sqlite3BtreeDropTable(Btree*, int, int*);
 int sqlite3BtreeClearTable(Btree*, int, int*);
+int sqlite3BtreeClearTableOfCursor(BtCursor*);
 void sqlite3BtreeTripAllCursors(Btree*, int);

 void sqlite3BtreeGetMeta(Btree *pBtree, int idx, u32 *pValue);
@@ -2669,7 +2669,7 @@ static void sqlite3RefillIndex(Parse *pParse, Index *pIndex, int memRootPage){

  /* Open the sorter cursor if we are to use one. */
  iSorter = pParse->nTab++;
-  sqlite3VdbeAddOp4(v, OP_SorterOpen, iSorter, 0, 0, (char*)
+  sqlite3VdbeAddOp4(v, OP_SorterOpen, iSorter, 0, pIndex->nKeyCol, (char*)
                    sqlite3KeyInfoRef(pKey), P4_KEYINFO);

  /* Open the table. Loop through all rows of the table, inserting index
@@ -3018,7 +3018,7 @@ Index *sqlite3CreateIndex(
      pParse->checkSchema = 1;
      goto exit_create_index;
    }
-    assert( pTab->nCol<=0x7fff && j<=0x7fff );
+    assert( j<=0x7fff );
    pIndex->aiColumn[i] = (i16)j;
    if( pListItem->pExpr ){
      int nColl;
@@ -33,6 +33,7 @@
 char sqlite3ExprAffinity(Expr *pExpr){
  int op;
  pExpr = sqlite3ExprSkipCollate(pExpr);
+  if( pExpr->flags & EP_Generic ) return SQLITE_AFF_NONE;
  op = pExpr->op;
  if( op==TK_SELECT ){
    assert( pExpr->flags&EP_xIsSelect );
@@ -65,7 +66,11 @@ char sqlite3ExprAffinity(Expr *pExpr){
 ** If a memory allocation error occurs, that fact is recorded in pParse->db
 ** and the pExpr parameter is returned unchanged.
 */
-Expr *sqlite3ExprAddCollateToken(Parse *pParse, Expr *pExpr, Token *pCollName){
+Expr *sqlite3ExprAddCollateToken(
+  Parse *pParse,           /* Parsing context */
+  Expr *pExpr,             /* Add the "COLLATE" clause to this expression */
+  const Token *pCollName   /* Name of collating sequence */
+){
  if( pCollName->n>0 ){
    Expr *pNew = sqlite3ExprAlloc(pParse->db, TK_COLLATE, pCollName, 1);
    if( pNew ){
@@ -118,6 +123,7 @@ CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr){
  Expr *p = pExpr;
  while( p ){
    int op = p->op;
+    if( p->flags & EP_Generic ) break;
    if( op==TK_CAST || op==TK_UPLUS ){
      p = p->pLeft;
      continue;
@@ -949,7 +955,6 @@ ExprList *sqlite3ExprListDup(sqlite3 *db, ExprList *p, int flags){
  if( p==0 ) return 0;
  pNew = sqlite3DbMallocRaw(db, sizeof(*pNew) );
  if( pNew==0 ) return 0;
-  pNew->iECursor = 0;
  pNew->nExpr = i = p->nExpr;
  if( (flags & EXPRDUP_REDUCE)==0 ) for(i=1; i<p->nExpr; i+=i){}
  pNew->a = pItem = sqlite3DbMallocRaw(db,  i*sizeof(p->a[0]) );
@@ -1062,7 +1067,6 @@ Select *sqlite3SelectDup(sqlite3 *db, Select *p, int flags){
  pNew->selFlags = p->selFlags & ~SF_UsesEphemeral;
  pNew->addrOpenEphm[0] = -1;
  pNew->addrOpenEphm[1] = -1;
-  pNew->addrOpenEphm[2] = -1;
  pNew->nSelectRow = p->nSelectRow;
  pNew->pWith = withDup(db, p->pWith);
  return pNew;
@@ -1630,7 +1634,6 @@ int sqlite3FindInIndex(Parse *pParse, Expr *pX, int *prNotFound){
      *prNotFound = rMayHaveNull = ++pParse->nMem;
      sqlite3VdbeAddOp2(v, OP_Null, 0, *prNotFound);
    }else{
-      testcase( pParse->nQueryLoop>0 );
      pParse->nQueryLoop = 0;
      if( pX->pLeft->iColumn<0 && !ExprHasProperty(pX, EP_xIsSelect) ){
        eType = IN_INDEX_ROWID;
@@ -2335,7 +2338,7 @@ void sqlite3ExprCodeMove(Parse *pParse, int iFrom, int iTo, int nReg){
  int i;
  struct yColCache *p;
  assert( iFrom>=iTo+nReg || iFrom+nReg<=iTo );
-  sqlite3VdbeAddOp3(pParse->pVdbe, OP_Move, iFrom, iTo, nReg-1);
+  sqlite3VdbeAddOp3(pParse->pVdbe, OP_Move, iFrom, iTo, nReg);
  for(i=0, p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++){
    int x = p->iReg;
    if( x>=iFrom && x<iFrom+nReg ){
@@ -2736,7 +2739,7 @@ int sqlite3ExprCodeTarget(Parse *pParse, Expr *pExpr, int target){
        }

        sqlite3ExprCachePush(pParse);     /* Ticket 2ea2425d34be */
-        sqlite3ExprCodeExprList(pParse, pFarg, r1, 
+        sqlite3ExprCodeExprList(pParse, pFarg, r1,
                                SQLITE_ECEL_DUP|SQLITE_ECEL_FACTOR);
        sqlite3ExprCachePop(pParse, 1);   /* Ticket 2ea2425d34be */
      }else{
@@ -167,6 +167,7 @@ SQLITE_WSD struct Sqlite3Config sqlite3Config = {
   0,                         /* nPage */
   0,                         /* mxParserStack */
   0,                         /* sharedCacheEnabled */
+   0,                         /* nWorker */
   /* All the rest should always be initialized to zero */
   0,                         /* isInit */
   0,                         /* inProgress */
@@ -515,6 +515,13 @@ int sqlite3_config(int op, ...){
    }
 #endif

+    case SQLITE_CONFIG_WORKER_THREADS: {
+      int n = va_arg(ap, int);
+      if( n>SQLITE_MAX_WORKER_THREADS ) n = SQLITE_MAX_WORKER_THREADS;
+      if( n>=0 ) sqlite3GlobalConfig.nWorker = n;
+      break;
+    }
+
    default: {
      rc = SQLITE_ERROR;
      break;
@@ -800,6 +807,7 @@ static void disconnectAllVtab(sqlite3 *db){
      }
    }
  }
+  sqlite3VtabUnlockList(db);
  sqlite3BtreeLeaveAll(db);
 #else
  UNUSED_PARAMETER(db);
@@ -2496,6 +2504,7 @@ static int openDatabase(
  db->nextAutovac = -1;
  db->szMmap = sqlite3GlobalConfig.szMmap;
  db->nextPagesize = 0;
+  db->nMaxSorterMmap = 0x7FFFFFFF;
  db->flags |= SQLITE_ShortColNames | SQLITE_EnableTrigger | SQLITE_CacheSpill
 #if !defined(SQLITE_DEFAULT_AUTOMATIC_INDEX) || SQLITE_DEFAULT_AUTOMATIC_INDEX
                 | SQLITE_AutoIndex
@@ -3322,6 +3331,13 @@ int sqlite3_test_control(int op, ...){
      break;
    }

+    /*   sqlite3_test_control(SQLITE_TESTCTRL_SORTER_MMAP, db, nMax); */
+    case SQLITE_TESTCTRL_SORTER_MMAP: {
+      sqlite3 *db = va_arg(ap, sqlite3*);
+      db->nMaxSorterMmap = va_arg(ap, int);
+      break;
+    }
+
  }
  va_end(ap);
 #endif /* SQLITE_OMIT_BUILTIN_TEST */
@@ -248,7 +248,7 @@ static void *memsys5MallocUnsafe(int nByte){
  ** block.  If not, then split a block of the next larger power of
  ** two in order to create a new free block of size iLogsize.
  */
-  for(iBin=iLogsize; mem5.aiFreelist[iBin]<0 && iBin<=LOGMAX; iBin++){}
+  for(iBin=iLogsize; iBin<=LOGMAX && mem5.aiFreelist[iBin]<0; iBin++){}
  if( iBin>LOGMAX ){
    testcase( sqlite3GlobalConfig.xLog!=0 );
    sqlite3_log(SQLITE_NOMEM, "failed to allocate %u bytes", nByte);
@@ -323,6 +323,7 @@ static int posixFchown(int fd, uid_t uid, gid_t gid){

 /* Forward reference */
 static int openDirectory(const char*, int*);
+static int unixGetpagesize(void);

 /*
 ** Many system calls are accessed through pointer-to-functions so that
@@ -446,6 +447,9 @@ static struct unix_syscall {
 #define osMremap ((void*(*)(void*,size_t,size_t,int,...))aSyscall[23].pCurrent)
 #endif

+  { "getpagesize",  (sqlite3_syscall_ptr)unixGetpagesize, 0 },
+#define osGetpagesize ((int(*)(void))aSyscall[24].pCurrent)
+
 }; /* End of the overrideable system calls */

 /*
@@ -4105,6 +4109,36 @@ static int unixShmSystemLock(
  return rc;        
 }

+/*
+** Return the system page size.
+**
+** This function should not be called directly by other code in this file. 
+** Instead, it should be called via macro osGetpagesize().
+*/
+static int unixGetpagesize(void){
+#if defined(_BSD_SOURCE)
+  return getpagesize();
+#else
+  return (int)sysconf(_SC_PAGESIZE);
+#endif
+}
+
+/*
+** Return the minimum number of 32KB shm regions that should be mapped at
+** a time, assuming that each mapping must be an integer multiple of the
+** current system page-size.
+**
+** Usually, this is 1. The exception seems to be systems that are configured
+** to use 64KB pages - in this case each mapping must cover at least two
+** shm regions.
+*/
+static int unixShmRegionPerMap(void){
+  int shmsz = 32*1024;            /* SHM region size */
+  int pgsz = osGetpagesize();   /* System page size */
+  assert( ((pgsz-1)&pgsz)==0 );   /* Page size must be a power of 2 */
+  if( pgsz<shmsz ) return 1;
+  return pgsz/shmsz;
+}

 /*
 ** Purge the unixShmNodeList list of all entries with unixShmNode.nRef==0.
@@ -4116,10 +4150,11 @@ static void unixShmPurge(unixFile *pFd){
  unixShmNode *p = pFd->pInode->pShmNode;
  assert( unixMutexHeld() );
  if( p && p->nRef==0 ){
+    int nShmPerMap = unixShmRegionPerMap();
    int i;
    assert( p->pInode==pFd->pInode );
    sqlite3_mutex_free(p->mutex);
-    for(i=0; i<p->nRegion; i++){
+    for(i=0; i<p->nRegion; i+=nShmPerMap){
      if( p->h>=0 ){
        osMunmap(p->apRegion[i], p->szRegion);
      }else{
@@ -4326,6 +4361,8 @@ static int unixShmMap(
  unixShm *p;
  unixShmNode *pShmNode;
  int rc = SQLITE_OK;
+  int nShmPerMap = unixShmRegionPerMap();
+  int nReqRegion;

  /* If the shared-memory file has not yet been opened, open it now. */
  if( pDbFd->pShm==0 ){
@@ -4341,9 +4378,12 @@ static int unixShmMap(
  assert( pShmNode->h>=0 || pDbFd->pInode->bProcessLock==1 );
  assert( pShmNode->h<0 || pDbFd->pInode->bProcessLock==0 );

-  if( pShmNode->nRegion<=iRegion ){
+  /* Minimum number of regions required to be mapped. */
+  nReqRegion = ((iRegion+nShmPerMap) / nShmPerMap) * nShmPerMap;
+
+  if( pShmNode->nRegion<nReqRegion ){
    char **apNew;                      /* New apRegion[] array */
-    int nByte = (iRegion+1)*szRegion;  /* Minimum required file size */
+    int nByte = nReqRegion*szRegion;   /* Minimum required file size */
    struct stat sStat;                 /* Used by fstat() */

    pShmNode->szRegion = szRegion;
@@ -4392,17 +4432,19 @@ static int unixShmMap(

    /* Map the requested memory region into this processes address space. */
    apNew = (char **)sqlite3_realloc(
-        pShmNode->apRegion, (iRegion+1)*sizeof(char *)
+        pShmNode->apRegion, nReqRegion*sizeof(char *)
    );
    if( !apNew ){
      rc = SQLITE_IOERR_NOMEM;
      goto shmpage_out;
    }
    pShmNode->apRegion = apNew;
-    while(pShmNode->nRegion<=iRegion){
+    while( pShmNode->nRegion<nReqRegion ){
+      int nMap = szRegion*nShmPerMap;
+      int i;
      void *pMem;
      if( pShmNode->h>=0 ){
-        pMem = osMmap(0, szRegion,
+        pMem = osMmap(0, nMap,
            pShmNode->isReadonly ? PROT_READ : PROT_READ|PROT_WRITE, 
            MAP_SHARED, pShmNode->h, szRegion*(i64)pShmNode->nRegion
        );
@@ -4418,8 +4460,11 @@ static int unixShmMap(
        }
        memset(pMem, 0, szRegion);
      }
-      pShmNode->apRegion[pShmNode->nRegion] = pMem;
-      pShmNode->nRegion++;
+
+      for(i=0; i<nShmPerMap; i++){
+        pShmNode->apRegion[pShmNode->nRegion+i] = &((char*)pMem)[szRegion*i];
+      }
+      pShmNode->nRegion += nShmPerMap;
    }
  }

@@ -4633,19 +4678,6 @@ static void unixUnmapfile(unixFile *pFd){
  }
 }

-/*
-** Return the system page size.
-*/
-static int unixGetPagesize(void){
-#if HAVE_MREMAP
-  return 512;
-#elif defined(_BSD_SOURCE)
-  return getpagesize();
-#else
-  return (int)sysconf(_SC_PAGESIZE);
-#endif
-}
-
 /*
 ** Attempt to set the size of the memory mapping maintained by file 
 ** descriptor pFd to nNew bytes. Any existing mapping is discarded.
@@ -4682,8 +4714,12 @@ static void unixRemapfile(
  if( (pFd->ctrlFlags & UNIXFILE_RDONLY)==0 ) flags |= PROT_WRITE;

  if( pOrig ){
-    const int szSyspage = unixGetPagesize();
+#if HAVE_MREMAP
+    i64 nReuse = pFd->mmapSize;
+#else
+    const int szSyspage = osGetpagesize();
    i64 nReuse = (pFd->mmapSize & ~(szSyspage-1));
+#endif
    u8 *pReq = &pOrig[nReuse];

    /* Unmap any pages of the existing mapping that cannot be reused. */
@@ -7429,7 +7465,7 @@ int sqlite3_os_init(void){

  /* Double-check that the aSyscall[] array has been constructed
  ** correctly.  See ticket [bb3a86e890c8e96ab] */
-  assert( ArraySize(aSyscall)==24 );
+  assert( ArraySize(aSyscall)==25 );

  /* Register all VFSes defined in the aVfs[] array */
  for(i=0; i<(sizeof(aVfs)/sizeof(sqlite3_vfs)); i++){
@@ -1279,6 +1279,13 @@ void sqlite3_win32_sleep(DWORD milliseconds){
 #endif
 }

+DWORD sqlite3Win32Wait(HANDLE hObject){
+  DWORD rc;
+  while( (rc = osWaitForSingleObjectEx(hObject, INFINITE,
+                                       TRUE))==WAIT_IO_COMPLETION ){}
+  return rc;
+}
+
 /*
 ** Return true (non-zero) if we are running under WinNT, Win2K, WinXP,
 ** or WinCE.  Return false (zero) for Win95, Win98, or WinME.
@@ -1624,12 +1624,11 @@ static int writeMasterJournal(Pager *pPager, const char *zMaster){

  if( !zMaster 
   || pPager->journalMode==PAGER_JOURNALMODE_MEMORY 
-   || pPager->journalMode==PAGER_JOURNALMODE_OFF 
+   || !isOpen(pPager->jfd)
  ){
    return SQLITE_OK;
  }
  pPager->setMaster = 1;
-  assert( isOpen(pPager->jfd) );
  assert( pPager->journalHdr <= pPager->journalOff );

  /* Calculate the length in bytes and the checksum of zMaster */
@@ -1020,6 +1020,33 @@ expr(A) ::= expr(W) between_op(N) expr(X) AND expr(Y). [BETWEEN] {
      */
      A.pExpr = sqlite3PExpr(pParse, TK_INTEGER, 0, 0, &sqlite3IntTokens[N]);
      sqlite3ExprDelete(pParse->db, X.pExpr);
+    }else if( Y->nExpr==1 ){
+      /* Expressions of the form:
+      **
+      **      expr1 IN (?1)
+      **      expr1 NOT IN (?2)
+      **
+      ** with exactly one value on the RHS can be simplified to something
+      ** like this:
+      **
+      **      expr1 == ?1
+      **      expr1 <> ?2
+      **
+      ** But, the RHS of the == or <> is marked with the EP_Generic flag
+      ** so that it may not contribute to the computation of comparison
+      ** affinity or the collating sequence to use for comparison.  Otherwise,
+      ** the semantics would be subtly different from IN or NOT IN.
+      */
+      Expr *pRHS = Y->a[0].pExpr;
+      Y->a[0].pExpr = 0;
+      sqlite3ExprListDelete(pParse->db, Y);
+      /* pRHS cannot be NULL because a malloc error would have been detected
+      ** before now and control would have never reached this point */
+      if( ALWAYS(pRHS) ){
+        pRHS->flags &= ~EP_Collate;
+        pRHS->flags |= EP_Generic;
+      }
+      A.pExpr = sqlite3PExpr(pParse, N ? TK_NE : TK_EQ, X.pExpr, pRHS, 0);
    }else{
      A.pExpr = sqlite3PExpr(pParse, TK_IN, X.pExpr, 0, 0);
      if( A.pExpr ){
@@ -824,7 +824,7 @@ void sqlite3Pragma(
  ** size of historical compatibility.
  */
  case PragTyp_DEFAULT_CACHE_SIZE: {
-    static const int iLn = __LINE__+2;
+    static const int iLn = VDBE_OFFSET_LINENO(2);
    static const VdbeOpList getCacheSize[] = {
      { OP_Transaction, 0, 0,        0},                         /* 0 */
      { OP_ReadCookie,  0, 1,        BTREE_DEFAULT_CACHE_SIZE},  /* 1 */
@@ -1087,7 +1087,7 @@ void sqlite3Pragma(
        ** file. Before writing to meta[6], check that meta[3] indicates
        ** that this really is an auto-vacuum capable database.
        */
-        static const int iLn = __LINE__+2;
+        static const int iLn = VDBE_OFFSET_LINENO(2);
        static const VdbeOpList setMeta6[] = {
          { OP_Transaction,    0,         1,                 0},    /* 0 */
          { OP_ReadCookie,     0,         1,         BTREE_LARGEST_ROOT_PAGE},
@@ -1790,7 +1790,7 @@ void sqlite3Pragma(
    ** messages have been generated, output OK.  Otherwise output the
    ** error message
    */
-    static const int iLn = __LINE__+2;
+    static const int iLn = VDBE_OFFSET_LINENO(2);
    static const VdbeOpList endCode[] = {
      { OP_AddImm,      1, 0,        0},    /* 0 */
      { OP_IfNeg,       1, 0,        0},    /* 1 */
@@ -1875,7 +1875,7 @@ void sqlite3Pragma(
      sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0,
         sqlite3MPrintf(db, "*** in database %s ***\n", db->aDb[i].zName),
         P4_DYNAMIC);
-      sqlite3VdbeAddOp2(v, OP_Move, 2, 4);
+      sqlite3VdbeAddOp3(v, OP_Move, 2, 4, 1);
      sqlite3VdbeAddOp3(v, OP_Concat, 4, 3, 2);
      sqlite3VdbeAddOp2(v, OP_ResultRow, 2, 1);
      sqlite3VdbeJumpHere(v, addr);
@@ -134,20 +134,6 @@ static char et_getdigit(LONGDOUBLE_TYPE *val, int *cnt){
 }
 #endif /* SQLITE_OMIT_FLOATING_POINT */

-/*
-** Append N space characters to the given string buffer.
-*/
-void sqlite3AppendSpace(StrAccum *pAccum, int N){
-  static const char zSpaces[] = "                             ";
-  while( N>=(int)sizeof(zSpaces)-1 ){
-    sqlite3StrAccumAppend(pAccum, zSpaces, sizeof(zSpaces)-1);
-    N -= sizeof(zSpaces)-1;
-  }
-  if( N>0 ){
-    sqlite3StrAccumAppend(pAccum, zSpaces, N);
-  }
-}
-
 /*
 ** Set the StrAccum object to an error mode.
 */
@@ -237,11 +223,9 @@ void sqlite3VXPrintf(
  }
  for(; (c=(*fmt))!=0; ++fmt){
    if( c!='%' ){
-      int amt;
      bufpt = (char *)fmt;
-      amt = 1;
-      while( (c=(*++fmt))!='%' && c!=0 ) amt++;
-      sqlite3StrAccumAppend(pAccum, bufpt, amt);
+      while( (c=(*++fmt))!='%' && c!=0 ){};
+      sqlite3StrAccumAppend(pAccum, bufpt, (int)(fmt - bufpt));
      if( c==0 ) break;
    }
    if( (c=(*++fmt))==0 ){
@@ -422,10 +406,8 @@ void sqlite3VXPrintf(
          *(--bufpt) = zOrd[x*2];
        }
        {
-          register const char *cset;      /* Use registers for speed */
-          register int base;
-          cset = &aDigits[infop->charset];
-          base = infop->base;
+          const char *cset = &aDigits[infop->charset];
+          u8 base = infop->base;
          do{                                           /* Convert to ascii */
            *(--bufpt) = cset[longvalue%base];
            longvalue = longvalue/base;
@@ -729,29 +711,89 @@ void sqlite3VXPrintf(
    ** "length" characters long.  The field width is "width".  Do
    ** the output.
    */
-    if( !flag_leftjustify ){
-      register int nspace;
-      nspace = width-length;
-      if( nspace>0 ){
-        sqlite3AppendSpace(pAccum, nspace);
-      }
-    }
-    if( length>0 ){
-      sqlite3StrAccumAppend(pAccum, bufpt, length);
-    }
-    if( flag_leftjustify ){
-      register int nspace;
-      nspace = width-length;
-      if( nspace>0 ){
-        sqlite3AppendSpace(pAccum, nspace);
-      }
-    }
+    width -= length;
+    if( width>0 && !flag_leftjustify ) sqlite3AppendSpace(pAccum, width);
+    sqlite3StrAccumAppend(pAccum, bufpt, length);
+    if( width>0 && flag_leftjustify ) sqlite3AppendSpace(pAccum, width);
+
    if( zExtra ) sqlite3_free(zExtra);
  }/* End for loop over the format string */
 } /* End of function */

 /*
-** Append N bytes of text from z to the StrAccum object.
+** Enlarge the memory allocation on a StrAccum object so that it is
+** able to accept at least N more bytes of text.
+**
+** Return the number of bytes of text that StrAccum is able to accept
+** after the attempted enlargement.  The value returned might be zero.
+*/
+static int sqlite3StrAccumEnlarge(StrAccum *p, int N){
+  char *zNew;
+  assert( p->nChar+N >= p->nAlloc ); /* Only called if really needed */
+  if( p->accError ){
+    testcase(p->accError==STRACCUM_TOOBIG);
+    testcase(p->accError==STRACCUM_NOMEM);
+    return 0;
+  }
+  if( !p->useMalloc ){
+    N = p->nAlloc - p->nChar - 1;
+    setStrAccumError(p, STRACCUM_TOOBIG);
+    return N;
+  }else{
+    char *zOld = (p->zText==p->zBase ? 0 : p->zText);
+    i64 szNew = p->nChar;
+    szNew += N + 1;
+    if( szNew > p->mxAlloc ){
+      sqlite3StrAccumReset(p);
+      setStrAccumError(p, STRACCUM_TOOBIG);
+      return 0;
+    }else{
+      p->nAlloc = (int)szNew;
+    }
+    if( p->useMalloc==1 ){
+      zNew = sqlite3DbRealloc(p->db, zOld, p->nAlloc);
+    }else{
+      zNew = sqlite3_realloc(zOld, p->nAlloc);
+    }
+    if( zNew ){
+      if( zOld==0 && p->nChar>0 ) memcpy(zNew, p->zText, p->nChar);
+      p->zText = zNew;
+    }else{
+      sqlite3StrAccumReset(p);
+      setStrAccumError(p, STRACCUM_NOMEM);
+      return 0;
+    }
+  }
+  return N;
+}
+
+/*
+** Append N space characters to the given string buffer.
+*/
+void sqlite3AppendSpace(StrAccum *p, int N){
+  if( p->nChar+N >= p->nAlloc && (N = sqlite3StrAccumEnlarge(p, N))<=0 ) return;
+  while( (N--)>0 ) p->zText[p->nChar++] = ' ';
+}
+
+/*
+** The StrAccum "p" is not large enough to accept N new bytes of z[].
+** So enlarge if first, then do the append.
+**
+** This is a helper routine to sqlite3StrAccumAppend() that does special-case
+** work (enlarging the buffer) using tail recursion, so that the
+** sqlite3StrAccumAppend() routine can use fast calling semantics.
+*/
+static void enlargeAndAppend(StrAccum *p, const char *z, int N){
+  N = sqlite3StrAccumEnlarge(p, N);
+  if( N>0 ){
+    memcpy(&p->zText[p->nChar], z, N);
+    p->nChar += N;
+  }
+}
+
+/*
+** Append N bytes of text from z to the StrAccum object.  Increase the
+** size of the memory allocation for StrAccum if necessary.
 */
 void sqlite3StrAccumAppend(StrAccum *p, const char *z, int N){
  assert( z!=0 );
@@ -759,43 +801,8 @@ void sqlite3StrAccumAppend(StrAccum *p, const char *z, int N){
  assert( N>=0 );
  assert( p->accError==0 || p->nAlloc==0 );
  if( p->nChar+N >= p->nAlloc ){
-    char *zNew;
-    if( p->accError ){
-      testcase(p->accError==STRACCUM_TOOBIG);
-      testcase(p->accError==STRACCUM_NOMEM);
-      return;
-    }
-    if( !p->useMalloc ){
-      N = p->nAlloc - p->nChar - 1;
-      setStrAccumError(p, STRACCUM_TOOBIG);
-      if( N<=0 ){
-        return;
-      }
-    }else{
-      char *zOld = (p->zText==p->zBase ? 0 : p->zText);
-      i64 szNew = p->nChar;
-      szNew += N + 1;
-      if( szNew > p->mxAlloc ){
-        sqlite3StrAccumReset(p);
-        setStrAccumError(p, STRACCUM_TOOBIG);
-        return;
-      }else{
-        p->nAlloc = (int)szNew;
-      }
-      if( p->useMalloc==1 ){
-        zNew = sqlite3DbRealloc(p->db, zOld, p->nAlloc);
-      }else{
-        zNew = sqlite3_realloc(zOld, p->nAlloc);
-      }
-      if( zNew ){
-        if( zOld==0 && p->nChar>0 ) memcpy(zNew, p->zText, p->nChar);
-        p->zText = zNew;
-      }else{
-        sqlite3StrAccumReset(p);
-        setStrAccumError(p, STRACCUM_NOMEM);
-        return;
-      }
-    }
+    enlargeAndAppend(p,z,N);
+    return;
  }
  assert( p->zText );
  memcpy(&p->zText[p->nChar], z, N);
@@ -14,6 +14,34 @@
 */
 #include "sqliteInt.h"

+/*
+** An instance of the following object is used to record information about
+** how to process the DISTINCT keyword, to simplify passing that information
+** into the selectInnerLoop() routine.
+*/
+typedef struct DistinctCtx DistinctCtx;
+struct DistinctCtx {
+  u8 isTnct;      /* True if the DISTINCT keyword is present */
+  u8 eTnctType;   /* One of the WHERE_DISTINCT_* operators */
+  int tabTnct;    /* Ephemeral table used for DISTINCT processing */
+  int addrTnct;   /* Address of OP_OpenEphemeral opcode for tabTnct */
+};
+
+/*
+** An instance of the following object is used to record information about
+** the ORDER BY (or GROUP BY) clause of query is being coded.
+*/
+typedef struct SortCtx SortCtx;
+struct SortCtx {
+  ExprList *pOrderBy;   /* The ORDER BY (or GROUP BY clause) */
+  int nOBSat;           /* Number of ORDER BY terms satisfied by indices */
+  int iECursor;         /* Cursor number for the sorter */
+  int regReturn;        /* Register holding block-output return address */
+  int labelBkOut;       /* Start label for the block-output subroutine */
+  int addrSortIndex;    /* Address of the OP_SorterOpen or OP_OpenEphemeral */
+  u8 sortFlags;         /* Zero or more SORTFLAG_* bits */
+};
+#define SORTFLAG_UseSorter  0x01   /* Use SorterOpen instead of OpenEphemeral */

 /*
 ** Delete all the content of a Select structure but do not deallocate
@@ -87,7 +115,6 @@ Select *sqlite3SelectNew(
  assert( pOffset==0 || pLimit!=0 );
  pNew->addrOpenEphm[0] = -1;
  pNew->addrOpenEphm[1] = -1;
-  pNew->addrOpenEphm[2] = -1;
  if( db->mallocFailed ) {
    clearSelect(db, pNew);
    if( pNew!=&standin ) sqlite3DbFree(db, pNew);
@@ -419,34 +446,98 @@ static int sqliteProcessJoin(Parse *pParse, Select *p){
  return 0;
 }

+/* Forward reference */
+static KeyInfo *keyInfoFromExprList(
+  Parse *pParse,       /* Parsing context */
+  ExprList *pList,     /* Form the KeyInfo object from this ExprList */
+  int iStart,          /* Begin with this column of pList */
+  int nExtra           /* Add this many extra columns to the end */
+);
+
 /*
-** Insert code into "v" that will push the record on the top of the
-** stack into the sorter.
+** Generate code that will push the record in registers regData
+** through regData+nData-1 onto the sorter.
 */
 static void pushOntoSorter(
  Parse *pParse,         /* Parser context */
-  ExprList *pOrderBy,    /* The ORDER BY clause */
+  SortCtx *pSort,        /* Information about the ORDER BY clause */
  Select *pSelect,       /* The whole SELECT statement */
-  int regData            /* Register holding data to be sorted */
+  int regData,           /* First register holding data to be sorted */
+  int nData,             /* Number of elements in the data array */
+  int nPrefixReg         /* No. of reg prior to regData available for use */
 ){
-  Vdbe *v = pParse->pVdbe;
-  int nExpr = pOrderBy->nExpr;
-  int regBase = sqlite3GetTempRange(pParse, nExpr+2);
-  int regRecord = sqlite3GetTempReg(pParse);
-  int op;
-  sqlite3ExprCacheClear(pParse);
-  sqlite3ExprCodeExprList(pParse, pOrderBy, regBase, 0);
-  sqlite3VdbeAddOp2(v, OP_Sequence, pOrderBy->iECursor, regBase+nExpr);
-  sqlite3ExprCodeMove(pParse, regData, regBase+nExpr+1, 1);
-  sqlite3VdbeAddOp3(v, OP_MakeRecord, regBase, nExpr + 2, regRecord);
-  if( pSelect->selFlags & SF_UseSorter ){
+  Vdbe *v = pParse->pVdbe;                         /* Stmt under construction */
+  int bSeq = ((pSort->sortFlags & SORTFLAG_UseSorter)==0);
+  int nExpr = pSort->pOrderBy->nExpr;              /* No. of ORDER BY terms */
+  int nBase = nExpr + bSeq + nData;                /* Fields in sorter record */
+  int regBase;                                     /* Regs for sorter record */
+  int regRecord = sqlite3GetTempReg(pParse);       /* Assembled sorter record */
+  int nOBSat = pSort->nOBSat;                      /* ORDER BY terms to skip */
+  int op;                            /* Opcode to add sorter record to sorter */
+
+  assert( bSeq==0 || bSeq==1 );
+  if( nPrefixReg ){
+    assert( nPrefixReg==nExpr+bSeq );
+    regBase = regData - nExpr - bSeq;
+  }else{
+    regBase = sqlite3GetTempRange(pParse, nBase);
+  }
+  sqlite3ExprCodeExprList(pParse, pSort->pOrderBy, regBase, SQLITE_ECEL_DUP);
+  if( bSeq ){
+    sqlite3VdbeAddOp2(v, OP_Sequence, pSort->iECursor, regBase+nExpr);
+  }
+  if( nPrefixReg==0 ){
+    sqlite3VdbeAddOp3(v, OP_Move, regData, regBase+nExpr+bSeq, nData);
+  }
+
+  sqlite3VdbeAddOp3(v, OP_MakeRecord, regBase+nOBSat, nBase-nOBSat, regRecord);
+  if( nOBSat>0 ){
+    int regPrevKey;   /* The first nOBSat columns of the previous row */
+    int addrFirst;    /* Address of the OP_IfNot opcode */
+    int addrJmp;      /* Address of the OP_Jump opcode */
+    VdbeOp *pOp;      /* Opcode that opens the sorter */
+    int nKey;         /* Number of sorting key columns, including OP_Sequence */
+    KeyInfo *pKI;     /* Original KeyInfo on the sorter table */
+
+    regPrevKey = pParse->nMem+1;
+    pParse->nMem += pSort->nOBSat;
+    nKey = nExpr - pSort->nOBSat + bSeq;
+    if( bSeq ){
+      addrFirst = sqlite3VdbeAddOp1(v, OP_IfNot, regBase+nExpr); 
+    }else{
+      addrFirst = sqlite3VdbeAddOp1(v, OP_SequenceTest, pSort->iECursor);
+    }
+    VdbeCoverage(v);
+    sqlite3VdbeAddOp3(v, OP_Compare, regPrevKey, regBase, pSort->nOBSat);
+    pOp = sqlite3VdbeGetOp(v, pSort->addrSortIndex);
+    if( pParse->db->mallocFailed ) return;
+    pOp->p2 = nKey + 1;
+    pKI = pOp->p4.pKeyInfo;
+    memset(pKI->aSortOrder, 0, pKI->nField); /* Makes OP_Jump below testable */
+    sqlite3VdbeChangeP4(v, -1, (char*)pKI, P4_KEYINFO);
+    pOp->p4.pKeyInfo = keyInfoFromExprList(pParse, pSort->pOrderBy, nOBSat, 1);
+    addrJmp = sqlite3VdbeCurrentAddr(v);
+    sqlite3VdbeAddOp3(v, OP_Jump, addrJmp+1, 0, addrJmp+1); VdbeCoverage(v);
+    pSort->labelBkOut = sqlite3VdbeMakeLabel(v);
+    pSort->regReturn = ++pParse->nMem;
+    sqlite3VdbeAddOp2(v, OP_Gosub, pSort->regReturn, pSort->labelBkOut);
+    sqlite3VdbeAddOp1(v, OP_ResetSorter, pSort->iECursor);
+    sqlite3VdbeJumpHere(v, addrFirst);
+    sqlite3VdbeAddOp3(v, OP_Move, regBase, regPrevKey, pSort->nOBSat);
+    sqlite3VdbeJumpHere(v, addrJmp);
+  }
+  if( pSort->sortFlags & SORTFLAG_UseSorter ){
    op = OP_SorterInsert;
  }else{
    op = OP_IdxInsert;
  }
-  sqlite3VdbeAddOp2(v, op, pOrderBy->iECursor, regRecord);
-  sqlite3ReleaseTempReg(pParse, regRecord);
-  sqlite3ReleaseTempRange(pParse, regBase, nExpr+2);
+  sqlite3VdbeAddOp2(v, op, pSort->iECursor, regRecord);
+  if( nOBSat==0 ){
+    sqlite3ReleaseTempReg(pParse, regRecord);
+    if( nPrefixReg==0 ){
+      sqlite3ReleaseTempRange(pParse, regBase, nBase);
+    }
+  }
  if( pSelect->iLimit ){
    int addr1, addr2;
    int iLimit;
@@ -459,8 +550,8 @@ static void pushOntoSorter(
    sqlite3VdbeAddOp2(v, OP_AddImm, iLimit, -1);
    addr2 = sqlite3VdbeAddOp0(v, OP_Goto);
    sqlite3VdbeJumpHere(v, addr1);
-    sqlite3VdbeAddOp1(v, OP_Last, pOrderBy->iECursor);
-    sqlite3VdbeAddOp1(v, OP_Delete, pOrderBy->iECursor);
+    sqlite3VdbeAddOp1(v, OP_Last, pSort->iECursor);
+    sqlite3VdbeAddOp1(v, OP_Delete, pSort->iECursor);
    sqlite3VdbeJumpHere(v, addr2);
  }
 }
@@ -473,7 +564,7 @@ static void codeOffset(
  int iOffset,      /* Register holding the offset counter */
  int iContinue     /* Jump here to skip the current record */
 ){
-  if( iOffset>0 && iContinue!=0 ){
+  if( iOffset>0 ){
    int addr;
    sqlite3VdbeAddOp2(v, OP_AddImm, iOffset, -1);
    addr = sqlite3VdbeAddOp1(v, OP_IfNeg, iOffset); VdbeCoverage(v);
@@ -534,19 +625,6 @@ static int checkForMultiColumnSelectError(
 }
 #endif

-/*
-** An instance of the following object is used to record information about
-** how to process the DISTINCT keyword, to simplify passing that information
-** into the selectInnerLoop() routine.
-*/
-typedef struct DistinctCtx DistinctCtx;
-struct DistinctCtx {
-  u8 isTnct;      /* True if the DISTINCT keyword is present */
-  u8 eTnctType;   /* One of the WHERE_DISTINCT_* operators */
-  int tabTnct;    /* Ephemeral table used for DISTINCT processing */
-  int addrTnct;   /* Address of OP_OpenEphemeral opcode for tabTnct */
-};
-
 /*
 ** This routine generates the code for the inside of the inner loop
 ** of a SELECT.
@@ -561,7 +639,7 @@ static void selectInnerLoop(
  Select *p,              /* The complete select statement being coded */
  ExprList *pEList,       /* List of values being extracted */
  int srcTab,             /* Pull data from this table */
-  ExprList *pOrderBy,     /* If not NULL, sort results using this key */
+  SortCtx *pSort,         /* If not NULL, info on how to process ORDER BY */
  DistinctCtx *pDistinct, /* If not NULL, info on how to process DISTINCT */
  SelectDest *pDest,      /* How to dispose of the results */
  int iContinue,          /* Jump here to continue with next row */
@@ -574,11 +652,14 @@ static void selectInnerLoop(
  int eDest = pDest->eDest;   /* How to dispose of results */
  int iParm = pDest->iSDParm; /* First argument to disposal method */
  int nResultCol;             /* Number of result columns */
+  int nPrefixReg = 0;         /* Number of extra registers before regResult */

  assert( v );
  assert( pEList!=0 );
  hasDistinct = pDistinct ? pDistinct->eTnctType : WHERE_DISTINCT_NOOP;
-  if( pOrderBy==0 && !hasDistinct ){
+  if( pSort && pSort->pOrderBy==0 ) pSort = 0;
+  if( pSort==0 && !hasDistinct ){
+    assert( iContinue!=0 );
    codeOffset(v, p->iOffset, iContinue);
  }

@@ -587,6 +668,11 @@ static void selectInnerLoop(
  nResultCol = pEList->nExpr;

  if( pDest->iSdst==0 ){
+    if( pSort ){
+      nPrefixReg = pSort->pOrderBy->nExpr;
+      if( !(pSort->sortFlags & SORTFLAG_UseSorter) ) nPrefixReg++;
+      pParse->nMem += nPrefixReg;
+    }
    pDest->iSdst = pParse->nMem+1;
    pParse->nMem += nResultCol;
  }else if( pDest->iSdst+nResultCol > pParse->nMem ){
@@ -668,7 +754,7 @@ static void selectInnerLoop(
        break;
      }
    }
-    if( pOrderBy==0 ){
+    if( pSort==0 ){
      codeOffset(v, p->iOffset, iContinue);
    }
  }
@@ -699,16 +785,17 @@ static void selectInnerLoop(

    /* Store the result as data using a unique key.
    */
-    case SRT_DistTable:
+    case SRT_Fifo:
+    case SRT_DistFifo:
    case SRT_Table:
    case SRT_EphemTab: {
-      int r1 = sqlite3GetTempReg(pParse);
+      int r1 = sqlite3GetTempRange(pParse, nPrefixReg+1);
      testcase( eDest==SRT_Table );
      testcase( eDest==SRT_EphemTab );
-      sqlite3VdbeAddOp3(v, OP_MakeRecord, regResult, nResultCol, r1);
+      sqlite3VdbeAddOp3(v, OP_MakeRecord, regResult, nResultCol, r1+nPrefixReg);
 #ifndef SQLITE_OMIT_CTE
-      if( eDest==SRT_DistTable ){
-        /* If the destination is DistTable, then cursor (iParm+1) is open
+      if( eDest==SRT_DistFifo ){
+        /* If the destination is DistFifo, then cursor (iParm+1) is open
        ** on an ephemeral index. If the current row is already present
        ** in the index, do not write it to the output. If not, add the
        ** current row to the index and proceed with writing it to the
@@ -716,11 +803,11 @@ static void selectInnerLoop(
        int addr = sqlite3VdbeCurrentAddr(v) + 4;
        sqlite3VdbeAddOp4Int(v, OP_Found, iParm+1, addr, r1, 0); VdbeCoverage(v);
        sqlite3VdbeAddOp2(v, OP_IdxInsert, iParm+1, r1);
-        assert( pOrderBy==0 );
+        assert( pSort==0 );
      }
 #endif
-      if( pOrderBy ){
-        pushOntoSorter(pParse, pOrderBy, p, r1);
+      if( pSort ){
+        pushOntoSorter(pParse, pSort, p, r1+nPrefixReg, 1, nPrefixReg);
      }else{
        int r2 = sqlite3GetTempReg(pParse);
        sqlite3VdbeAddOp2(v, OP_NewRowid, iParm, r2);
@@ -728,7 +815,7 @@ static void selectInnerLoop(
        sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
        sqlite3ReleaseTempReg(pParse, r2);
      }
-      sqlite3ReleaseTempReg(pParse, r1);
+      sqlite3ReleaseTempRange(pParse, r1, nPrefixReg+1);
      break;
    }

@@ -741,12 +828,12 @@ static void selectInnerLoop(
      assert( nResultCol==1 );
      pDest->affSdst =
                  sqlite3CompareAffinity(pEList->a[0].pExpr, pDest->affSdst);
-      if( pOrderBy ){
+      if( pSort ){
        /* At first glance you would think we could optimize out the
        ** ORDER BY in this case since the order of entries in the set
        ** does not matter.  But there might be a LIMIT clause, in which
        ** case the order does matter */
-        pushOntoSorter(pParse, pOrderBy, p, regResult);
+        pushOntoSorter(pParse, pSort, p, regResult, 1, nPrefixReg);
      }else{
        int r1 = sqlite3GetTempReg(pParse);
        sqlite3VdbeAddOp4(v, OP_MakeRecord, regResult,1,r1, &pDest->affSdst, 1);
@@ -771,8 +858,8 @@ static void selectInnerLoop(
    */
    case SRT_Mem: {
      assert( nResultCol==1 );
-      if( pOrderBy ){
-        pushOntoSorter(pParse, pOrderBy, p, regResult);
+      if( pSort ){
+        pushOntoSorter(pParse, pSort, p, regResult, 1, nPrefixReg);
      }else{
        sqlite3ExprCodeMove(pParse, regResult, iParm, 1);
        /* The LIMIT clause will jump out of the loop for us */
@@ -785,11 +872,8 @@ static void selectInnerLoop(
    case SRT_Output: {        /* Return the results */
      testcase( eDest==SRT_Coroutine );
      testcase( eDest==SRT_Output );
-      if( pOrderBy ){
-        int r1 = sqlite3GetTempReg(pParse);
-        sqlite3VdbeAddOp3(v, OP_MakeRecord, regResult, nResultCol, r1);
-        pushOntoSorter(pParse, pOrderBy, p, r1);
-        sqlite3ReleaseTempReg(pParse, r1);
+      if( pSort ){
+        pushOntoSorter(pParse, pSort, p, regResult, nResultCol, nPrefixReg);
      }else if( eDest==SRT_Coroutine ){
        sqlite3VdbeAddOp1(v, OP_Yield, pDest->iSDParm);
      }else{
@@ -865,7 +949,7 @@ static void selectInnerLoop(
  ** there is a sorter, in which case the sorter has already limited
  ** the output for us.
  */
-  if( pOrderBy==0 && p->iLimit ){
+  if( pSort==0 && p->iLimit ){
    sqlite3VdbeAddOp3(v, OP_IfZero, p->iLimit, iBreak, -1); VdbeCoverage(v);
  }
 }
@@ -936,7 +1020,12 @@ int sqlite3KeyInfoIsWriteable(KeyInfo *p){ return p->nRef==1; }
 ** function is responsible for seeing that this structure is eventually
 ** freed.
 */
-static KeyInfo *keyInfoFromExprList(Parse *pParse, ExprList *pList, int nExtra){
+static KeyInfo *keyInfoFromExprList(
+  Parse *pParse,       /* Parsing context */
+  ExprList *pList,     /* Form the KeyInfo object from this ExprList */
+  int iStart,          /* Begin with this column of pList */
+  int nExtra           /* Add this many extra columns to the end */
+){
  int nExpr;
  KeyInfo *pInfo;
  struct ExprList_item *pItem;
@@ -944,15 +1033,15 @@ static KeyInfo *keyInfoFromExprList(Parse *pParse, ExprList *pList, int nExtra){
  int i;

  nExpr = pList->nExpr;
-  pInfo = sqlite3KeyInfoAlloc(db, nExpr+nExtra, 1);
+  pInfo = sqlite3KeyInfoAlloc(db, nExpr+nExtra-iStart, 1);
  if( pInfo ){
    assert( sqlite3KeyInfoIsWriteable(pInfo) );
-    for(i=0, pItem=pList->a; i<nExpr; i++, pItem++){
+    for(i=iStart, pItem=pList->a+iStart; i<nExpr; i++, pItem++){
      CollSeq *pColl;
      pColl = sqlite3ExprCollSeq(pParse, pItem->pExpr);
      if( !pColl ) pColl = db->pDfltColl;
-      pInfo->aColl[i] = pColl;
-      pInfo->aSortOrder[i] = pItem->sortOrder;
+      pInfo->aColl[i-iStart] = pColl;
+      pInfo->aSortOrder[i-iStart] = pItem->sortOrder;
    }
  }
  return pInfo;
@@ -1054,46 +1143,72 @@ static void explainComposite(
 static void generateSortTail(
  Parse *pParse,    /* Parsing context */
  Select *p,        /* The SELECT statement */
-  Vdbe *v,          /* Generate code into this VDBE */
+  SortCtx *pSort,   /* Information on the ORDER BY clause */
  int nColumn,      /* Number of columns of data */
  SelectDest *pDest /* Write the sorted results here */
 ){
+  Vdbe *v = pParse->pVdbe;                     /* The prepared statement */
  int addrBreak = sqlite3VdbeMakeLabel(v);     /* Jump here to exit loop */
  int addrContinue = sqlite3VdbeMakeLabel(v);  /* Jump here for next cycle */
  int addr;
+  int addrOnce = 0;
  int iTab;
-  int pseudoTab = 0;
-  ExprList *pOrderBy = p->pOrderBy;
-
+  ExprList *pOrderBy = pSort->pOrderBy;
  int eDest = pDest->eDest;
  int iParm = pDest->iSDParm;
-
  int regRow;
  int regRowid;
+  int nKey;
+  int iSortTab;                   /* Sorter cursor to read from */
+  int nSortData;                  /* Trailing values to read from sorter */
+  u8 p5;                          /* p5 parameter for 1st OP_Column */
+  int i;
+  int bSeq;                       /* True if sorter record includes seq. no. */
+#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
+  struct ExprList_item *aOutEx = p->pEList->a;
+#endif

-  iTab = pOrderBy->iECursor;
-  regRow = sqlite3GetTempReg(pParse);
+  if( pSort->labelBkOut ){
+    sqlite3VdbeAddOp2(v, OP_Gosub, pSort->regReturn, pSort->labelBkOut);
+    sqlite3VdbeAddOp2(v, OP_Goto, 0, addrBreak);
+    sqlite3VdbeResolveLabel(v, pSort->labelBkOut);
+  }
+  iTab = pSort->iECursor;
  if( eDest==SRT_Output || eDest==SRT_Coroutine ){
-    pseudoTab = pParse->nTab++;
-    sqlite3VdbeAddOp3(v, OP_OpenPseudo, pseudoTab, regRow, nColumn);
    regRowid = 0;
+    regRow = pDest->iSdst;
+    nSortData = nColumn;
  }else{
    regRowid = sqlite3GetTempReg(pParse);
+    regRow = sqlite3GetTempReg(pParse);
+    nSortData = 1;
  }
-  if( p->selFlags & SF_UseSorter ){
+  nKey = pOrderBy->nExpr - pSort->nOBSat;
+  if( pSort->sortFlags & SORTFLAG_UseSorter ){
    int regSortOut = ++pParse->nMem;
-    int ptab2 = pParse->nTab++;
-    sqlite3VdbeAddOp3(v, OP_OpenPseudo, ptab2, regSortOut, pOrderBy->nExpr+2);
+    iSortTab = pParse->nTab++;
+    if( pSort->labelBkOut ){
+      addrOnce = sqlite3CodeOnce(pParse); VdbeCoverage(v);
+    }
+    sqlite3VdbeAddOp3(v, OP_OpenPseudo, iSortTab, regSortOut, nKey+1+nSortData);
+    if( addrOnce ) sqlite3VdbeJumpHere(v, addrOnce);
    addr = 1 + sqlite3VdbeAddOp2(v, OP_SorterSort, iTab, addrBreak);
    VdbeCoverage(v);
    codeOffset(v, p->iOffset, addrContinue);
    sqlite3VdbeAddOp2(v, OP_SorterData, iTab, regSortOut);
-    sqlite3VdbeAddOp3(v, OP_Column, ptab2, pOrderBy->nExpr+1, regRow);
-    sqlite3VdbeChangeP5(v, OPFLAG_CLEARCACHE);
+    p5 = OPFLAG_CLEARCACHE;
+    bSeq = 0;
  }else{
    addr = 1 + sqlite3VdbeAddOp2(v, OP_Sort, iTab, addrBreak); VdbeCoverage(v);
    codeOffset(v, p->iOffset, addrContinue);
-    sqlite3VdbeAddOp3(v, OP_Column, iTab, pOrderBy->nExpr+1, regRow);
+    iSortTab = iTab;
+    p5 = 0;
+    bSeq = 1;
+  }
+  for(i=0; i<nSortData; i++){
+    sqlite3VdbeAddOp3(v, OP_Column, iSortTab, nKey+bSeq+i, regRow+i);
+    if( i==0 ) sqlite3VdbeChangeP5(v, p5);
+    VdbeComment((v, "%s", aOutEx[i].zName ? aOutEx[i].zName : aOutEx[i].zSpan));
  }
  switch( eDest ){
    case SRT_Table:
@@ -1122,17 +1237,9 @@ static void generateSortTail(
    }
 #endif
    default: {
-      int i;
      assert( eDest==SRT_Output || eDest==SRT_Coroutine ); 
      testcase( eDest==SRT_Output );
      testcase( eDest==SRT_Coroutine );
-      for(i=0; i<nColumn; i++){
-        assert( regRow!=pDest->iSdst+i );
-        sqlite3VdbeAddOp3(v, OP_Column, pseudoTab, i, pDest->iSdst+i);
-        if( i==0 ){
-          sqlite3VdbeChangeP5(v, OPFLAG_CLEARCACHE);
-        }
-      }
      if( eDest==SRT_Output ){
        sqlite3VdbeAddOp2(v, OP_ResultRow, pDest->iSdst, nColumn);
        sqlite3ExprCacheAffinityChange(pParse, pDest->iSdst, nColumn);
@@ -1142,21 +1249,20 @@ static void generateSortTail(
      break;
    }
  }
-  sqlite3ReleaseTempReg(pParse, regRow);
-  sqlite3ReleaseTempReg(pParse, regRowid);
-
+  if( regRowid ){
+    sqlite3ReleaseTempReg(pParse, regRow);
+    sqlite3ReleaseTempReg(pParse, regRowid);
+  }
  /* The bottom of the loop
  */
  sqlite3VdbeResolveLabel(v, addrContinue);
-  if( p->selFlags & SF_UseSorter ){
+  if( pSort->sortFlags & SORTFLAG_UseSorter ){
    sqlite3VdbeAddOp2(v, OP_SorterNext, iTab, addr); VdbeCoverage(v);
  }else{
    sqlite3VdbeAddOp2(v, OP_Next, iTab, addr); VdbeCoverage(v);
  }
+  if( pSort->regReturn ) sqlite3VdbeAddOp1(v, OP_Return, pSort->regReturn);
  sqlite3VdbeResolveLabel(v, addrBreak);
-  if( eDest==SRT_Output || eDest==SRT_Coroutine ){
-    sqlite3VdbeAddOp2(v, OP_Close, pseudoTab, 0);
-  }
 }

 /*
@@ -1834,7 +1940,7 @@ static void generateWithRecursiveQuery(
  int regCurrent;               /* Register holding Current table */
  int iQueue;                   /* The Queue table */
  int iDistinct = 0;            /* To ensure unique results if UNION */
-  int eDest = SRT_Table;        /* How to write to Queue */
+  int eDest = SRT_Fifo;         /* How to write to Queue */
  SelectDest destQueue;         /* SelectDest targetting the Queue table */
  int i;                        /* Loop counter */
  int rc;                       /* Result code */
@@ -1866,13 +1972,13 @@ static void generateWithRecursiveQuery(

  /* Allocate cursors numbers for Queue and Distinct.  The cursor number for
  ** the Distinct table must be exactly one greater than Queue in order
-  ** for the SRT_DistTable and SRT_DistQueue destinations to work. */
+  ** for the SRT_DistFifo and SRT_DistQueue destinations to work. */
  iQueue = pParse->nTab++;
  if( p->op==TK_UNION ){
-    eDest = pOrderBy ? SRT_DistQueue : SRT_DistTable;
+    eDest = pOrderBy ? SRT_DistQueue : SRT_DistFifo;
    iDistinct = pParse->nTab++;
  }else{
-    eDest = pOrderBy ? SRT_Queue : SRT_Table;
+    eDest = pOrderBy ? SRT_Queue : SRT_Fifo;
  }
  sqlite3SelectDestInit(&destQueue, eDest, iQueue);

@@ -1938,6 +2044,7 @@ static void generateWithRecursiveQuery(
  sqlite3VdbeResolveLabel(v, addrBreak);

 end_of_recursive_query:
+  sqlite3ExprListDelete(pParse->db, p->pOrderBy);
  p->pOrderBy = pOrderBy;
  p->pLimit = pLimit;
  p->pOffset = pOffset;
@@ -4309,7 +4416,7 @@ static void resetAccumulator(Parse *pParse, AggInfo *pAggInfo){
           "argument");
        pFunc->iDistinct = -1;
      }else{
-        KeyInfo *pKeyInfo = keyInfoFromExprList(pParse, pE->x.pList, 0);
+        KeyInfo *pKeyInfo = keyInfoFromExprList(pParse, pE->x.pList, 0, 0);
        sqlite3VdbeAddOp4(v, OP_OpenEphemeral, pFunc->iDistinct, 0, 0,
                          (char*)pKeyInfo, P4_KEYINFO);
      }
@@ -4464,12 +4571,11 @@ int sqlite3Select(
  ExprList *pEList;      /* List of columns to extract. */
  SrcList *pTabList;     /* List of tables to select from */
  Expr *pWhere;          /* The WHERE clause.  May be NULL */
-  ExprList *pOrderBy;    /* The ORDER BY clause.  May be NULL */
  ExprList *pGroupBy;    /* The GROUP BY clause.  May be NULL */
  Expr *pHaving;         /* The HAVING clause.  May be NULL */
  int rc = 1;            /* Value to return from this function */
-  int addrSortIndex;     /* Address of an OP_OpenEphemeral instruction */
  DistinctCtx sDistinct; /* Info on how to code the DISTINCT keyword */
+  SortCtx sSort;         /* Info on how to code the ORDER BY clause */
  AggInfo sAggInfo;      /* Information used by aggregate queries */
  int iEnd;              /* Address of the end of the query */
  sqlite3 *db;           /* The database connection */
@@ -4486,9 +4592,15 @@ int sqlite3Select(
  if( sqlite3AuthCheck(pParse, SQLITE_SELECT, 0, 0, 0) ) return 1;
  memset(&sAggInfo, 0, sizeof(sAggInfo));

+  assert( p->pOrderBy==0 || pDest->eDest!=SRT_DistFifo );
+  assert( p->pOrderBy==0 || pDest->eDest!=SRT_Fifo );
+  assert( p->pOrderBy==0 || pDest->eDest!=SRT_DistQueue );
+  assert( p->pOrderBy==0 || pDest->eDest!=SRT_Queue );
  if( IgnorableOrderby(pDest) ){
    assert(pDest->eDest==SRT_Exists || pDest->eDest==SRT_Union || 
-           pDest->eDest==SRT_Except || pDest->eDest==SRT_Discard);
+           pDest->eDest==SRT_Except || pDest->eDest==SRT_Discard ||
+           pDest->eDest==SRT_Queue  || pDest->eDest==SRT_DistFifo ||
+           pDest->eDest==SRT_DistQueue || pDest->eDest==SRT_Fifo);
    /* If ORDER BY makes no difference in the output then neither does
    ** DISTINCT so it can be removed too. */
    sqlite3ExprListDelete(db, p->pOrderBy);
@@ -4496,7 +4608,8 @@ int sqlite3Select(
    p->selFlags &= ~SF_Distinct;
  }
  sqlite3SelectPrep(pParse, p, 0);
-  pOrderBy = p->pOrderBy;
+  memset(&sSort, 0, sizeof(sSort));
+  sSort.pOrderBy = p->pOrderBy;
  pTabList = p->pSrc;
  pEList = p->pEList;
  if( pParse->nErr || db->mallocFailed ){
@@ -4618,7 +4731,7 @@ int sqlite3Select(
    pParse->nHeight -= sqlite3SelectExprHeight(p);
    pTabList = p->pSrc;
    if( !IgnorableOrderby(pDest) ){
-      pOrderBy = p->pOrderBy;
+      sSort.pOrderBy = p->pOrderBy;
    }
  }
  pEList = p->pEList;
@@ -4645,9 +4758,9 @@ int sqlite3Select(
  ** Use the SQLITE_GroupByOrder flag with SQLITE_TESTCTRL_OPTIMIZER
  ** to disable this optimization for testing purposes.
  */
-  if( sqlite3ExprListCompare(p->pGroupBy, pOrderBy, -1)==0
+  if( sqlite3ExprListCompare(p->pGroupBy, sSort.pOrderBy, -1)==0
         && OptimizationEnabled(db, SQLITE_GroupByOrder) ){
-    pOrderBy = 0;
+    sSort.pOrderBy = 0;
  }

  /* If the query is DISTINCT with an ORDER BY but is not an aggregate, and 
@@ -4666,12 +4779,12 @@ int sqlite3Select(
  ** BY and DISTINCT, and an index or separate temp-table for the other.
  */
  if( (p->selFlags & (SF_Distinct|SF_Aggregate))==SF_Distinct 
-   && sqlite3ExprListCompare(pOrderBy, p->pEList, -1)==0
+   && sqlite3ExprListCompare(sSort.pOrderBy, p->pEList, -1)==0
  ){
    p->selFlags &= ~SF_Distinct;
    p->pGroupBy = sqlite3ExprListDup(db, p->pEList, 0);
    pGroupBy = p->pGroupBy;
-    pOrderBy = 0;
+    sSort.pOrderBy = 0;
    /* Notice that even thought SF_Distinct has been cleared from p->selFlags,
    ** the sDistinct.isTnct is still set.  Hence, isTnct represents the
    ** original setting of the SF_Distinct flag, not the current setting */
@@ -4685,16 +4798,17 @@ int sqlite3Select(
  ** we figure out that the sorting index is not needed.  The addrSortIndex
  ** variable is used to facilitate that change.
  */
-  if( pOrderBy ){
+  if( sSort.pOrderBy ){
    KeyInfo *pKeyInfo;
-    pKeyInfo = keyInfoFromExprList(pParse, pOrderBy, 0);
-    pOrderBy->iECursor = pParse->nTab++;
-    p->addrOpenEphm[2] = addrSortIndex =
+    pKeyInfo = keyInfoFromExprList(pParse, sSort.pOrderBy, 0, 0);
+    sSort.iECursor = pParse->nTab++;
+    sSort.addrSortIndex =
      sqlite3VdbeAddOp4(v, OP_OpenEphemeral,
-                           pOrderBy->iECursor, pOrderBy->nExpr+2, 0,
-                           (char*)pKeyInfo, P4_KEYINFO);
+          sSort.iECursor, sSort.pOrderBy->nExpr+1+pEList->nExpr, 0,
+          (char*)pKeyInfo, P4_KEYINFO
+      );
  }else{
-    addrSortIndex = -1;
+    sSort.addrSortIndex = -1;
  }

  /* If the output is destined for a temporary table, open that table.
@@ -4708,9 +4822,9 @@ int sqlite3Select(
  iEnd = sqlite3VdbeMakeLabel(v);
  p->nSelectRow = LARGEST_INT64;
  computeLimitRegisters(pParse, p, iEnd);
-  if( p->iLimit==0 && addrSortIndex>=0 ){
-    sqlite3VdbeGetOp(v, addrSortIndex)->opcode = OP_SorterOpen;
-    p->selFlags |= SF_UseSorter;
+  if( p->iLimit==0 && sSort.addrSortIndex>=0 ){
+    sqlite3VdbeGetOp(v, sSort.addrSortIndex)->opcode = OP_SorterOpen;
+    sSort.sortFlags |= SORTFLAG_UseSorter;
  }

  /* Open a virtual index to use for the distinct set.
@@ -4719,7 +4833,7 @@ int sqlite3Select(
    sDistinct.tabTnct = pParse->nTab++;
    sDistinct.addrTnct = sqlite3VdbeAddOp4(v, OP_OpenEphemeral,
                                sDistinct.tabTnct, 0, 0,
-                                (char*)keyInfoFromExprList(pParse, p->pEList, 0),
+                                (char*)keyInfoFromExprList(pParse, p->pEList,0,0),
                                P4_KEYINFO);
    sqlite3VdbeChangeP5(v, BTREE_UNORDERED);
    sDistinct.eTnctType = WHERE_DISTINCT_UNORDERED;
@@ -4732,8 +4846,8 @@ int sqlite3Select(
    u16 wctrlFlags = (sDistinct.isTnct ? WHERE_WANT_DISTINCT : 0);

    /* Begin the database scan. */
-    pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, pOrderBy, p->pEList,
-                               wctrlFlags, 0);
+    pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, sSort.pOrderBy,
+                               p->pEList, wctrlFlags, 0);
    if( pWInfo==0 ) goto select_end;
    if( sqlite3WhereOutputRowCount(pWInfo) < p->nSelectRow ){
      p->nSelectRow = sqlite3WhereOutputRowCount(pWInfo);
@@ -4741,19 +4855,23 @@ int sqlite3Select(
    if( sDistinct.isTnct && sqlite3WhereIsDistinct(pWInfo) ){
      sDistinct.eTnctType = sqlite3WhereIsDistinct(pWInfo);
    }
-    if( pOrderBy && sqlite3WhereIsOrdered(pWInfo) ) pOrderBy = 0;
+    if( sSort.pOrderBy ){
+      sSort.nOBSat = sqlite3WhereIsOrdered(pWInfo);
+      if( sSort.nOBSat==sSort.pOrderBy->nExpr ){
+        sSort.pOrderBy = 0;
+      }
+    }

    /* If sorting index that was created by a prior OP_OpenEphemeral 
    ** instruction ended up not being needed, then change the OP_OpenEphemeral
    ** into an OP_Noop.
    */
-    if( addrSortIndex>=0 && pOrderBy==0 ){
-      sqlite3VdbeChangeToNoop(v, addrSortIndex);
-      p->addrOpenEphm[2] = -1;
+    if( sSort.addrSortIndex>=0 && sSort.pOrderBy==0 ){
+      sqlite3VdbeChangeToNoop(v, sSort.addrSortIndex);
    }

    /* Use the standard inner loop. */
-    selectInnerLoop(pParse, p, pEList, -1, pOrderBy, &sDistinct, pDest,
+    selectInnerLoop(pParse, p, pEList, -1, &sSort, &sDistinct, pDest,
                    sqlite3WhereContinueLabel(pWInfo),
                    sqlite3WhereBreakLabel(pWInfo));

@@ -4806,10 +4924,10 @@ int sqlite3Select(
    sNC.pSrcList = pTabList;
    sNC.pAggInfo = &sAggInfo;
    sAggInfo.mnReg = pParse->nMem+1;
-    sAggInfo.nSortingColumn = pGroupBy ? pGroupBy->nExpr+1 : 0;
+    sAggInfo.nSortingColumn = pGroupBy ? pGroupBy->nExpr : 0;
    sAggInfo.pGroupBy = pGroupBy;
    sqlite3ExprAnalyzeAggList(&sNC, pEList);
-    sqlite3ExprAnalyzeAggList(&sNC, pOrderBy);
+    sqlite3ExprAnalyzeAggList(&sNC, sSort.pOrderBy);
    if( pHaving ){
      sqlite3ExprAnalyzeAggregates(&sNC, pHaving);
    }
@@ -4843,7 +4961,7 @@ int sqlite3Select(
      ** will be converted into a Noop.  
      */
      sAggInfo.sortingIdx = pParse->nTab++;
-      pKeyInfo = keyInfoFromExprList(pParse, pGroupBy, 0);
+      pKeyInfo = keyInfoFromExprList(pParse, pGroupBy, 0, 0);
      addrSortingIdx = sqlite3VdbeAddOp4(v, OP_SorterOpen, 
          sAggInfo.sortingIdx, sAggInfo.nSortingColumn, 
          0, (char*)pKeyInfo, P4_KEYINFO);
@@ -4872,10 +4990,10 @@ int sqlite3Select(
      ** in the right order to begin with.
      */
      sqlite3VdbeAddOp2(v, OP_Gosub, regReset, addrReset);
-      pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, pGroupBy, 0, 
+      pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, pGroupBy, 0,
                                 WHERE_GROUPBY, 0);
      if( pWInfo==0 ) goto select_end;
-      if( sqlite3WhereIsOrdered(pWInfo) ){
+      if( sqlite3WhereIsOrdered(pWInfo)==pGroupBy->nExpr ){
        /* The optimizer is able to deliver rows in group by order so
        ** we do not have to sort.  The OP_OpenEphemeral table will be
        ** cancelled later because we still need to use the pKeyInfo
@@ -4898,8 +5016,8 @@ int sqlite3Select(

        groupBySort = 1;
        nGroupBy = pGroupBy->nExpr;
-        nCol = nGroupBy + 1;
-        j = nGroupBy+1;
+        nCol = nGroupBy;
+        j = nGroupBy;
        for(i=0; i<sAggInfo.nColumn; i++){
          if( sAggInfo.aCol[i].iSorterColumn>=j ){
            nCol++;
@@ -4909,8 +5027,7 @@ int sqlite3Select(
        regBase = sqlite3GetTempRange(pParse, nCol);
        sqlite3ExprCacheClear(pParse);
        sqlite3ExprCodeExprList(pParse, pGroupBy, regBase, 0);
-        sqlite3VdbeAddOp2(v, OP_Sequence, sAggInfo.sortingIdx,regBase+nGroupBy);
-        j = nGroupBy+1;
+        j = nGroupBy;
        for(i=0; i<sAggInfo.nColumn; i++){
          struct AggInfo_col *pCol = &sAggInfo.aCol[i];
          if( pCol->iSorterColumn>=j ){
@@ -5026,7 +5143,7 @@ int sqlite3Select(
      sqlite3VdbeAddOp1(v, OP_Return, regOutputRow);
      finalizeAggFunctions(pParse, &sAggInfo);
      sqlite3ExprIfFalse(pParse, pHaving, addrOutputRow+1, SQLITE_JUMPIFNULL);
-      selectInnerLoop(pParse, p, p->pEList, -1, pOrderBy,
+      selectInnerLoop(pParse, p, p->pEList, -1, &sSort,
                      &sDistinct, pDest,
                      addrOutputRow+1, addrSetAbort);
      sqlite3VdbeAddOp1(v, OP_Return, regOutputRow);
@@ -5158,7 +5275,7 @@ int sqlite3Select(
        }
        updateAccumulator(pParse, &sAggInfo);
        assert( pMinMax==0 || pMinMax->nExpr==1 );
-        if( sqlite3WhereIsOrdered(pWInfo) ){
+        if( sqlite3WhereIsOrdered(pWInfo)>0 ){
          sqlite3VdbeAddOp2(v, OP_Goto, 0, sqlite3WhereBreakLabel(pWInfo));
          VdbeComment((v, "%s() by index",
                (flag==WHERE_ORDERBY_MIN?"min":"max")));
@@ -5167,7 +5284,7 @@ int sqlite3Select(
        finalizeAggFunctions(pParse, &sAggInfo);
      }

-      pOrderBy = 0;
+      sSort.pOrderBy = 0;
      sqlite3ExprIfFalse(pParse, pHaving, addrEnd, SQLITE_JUMPIFNULL);
      selectInnerLoop(pParse, p, p->pEList, -1, 0, 0, 
                      pDest, addrEnd, addrEnd);
@@ -5184,9 +5301,9 @@ int sqlite3Select(
  /* If there is an ORDER BY clause, then we need to sort the results
  ** and send them to the callback one by one.
  */
-  if( pOrderBy ){
-    explainTempTable(pParse, "ORDER BY");
-    generateSortTail(pParse, p, v, pEList->nExpr, pDest);
+  if( sSort.pOrderBy ){
+    explainTempTable(pParse, sSort.nOBSat>0 ? "RIGHT PART OF ORDER BY":"ORDER BY");
+    generateSortTail(pParse, p, &sSort, pEList->nExpr, pDest);
  }

  /* Jump here to skip this query
@@ -1195,7 +1195,8 @@ static void explain_data_prepare(struct callback_data *p, sqlite3_stmt *pSql){
  int nAlloc = 0;                 /* Allocated size of p->aiIndent[], abYield */
  int iOp;                        /* Index of operation in p->aiIndent[] */

-  const char *azNext[] = { "Next", "Prev", "VPrev", "VNext", "SorterNext", 0 };
+  const char *azNext[] = { "Next", "Prev", "VPrev", "VNext", "SorterNext",
+                           "NextIfOpen", "PrevIfOpen", 0 };
  const char *azYield[] = { "Yield", "SeekLt", "SeekGt", "RowSetRead", "Rewind", 0 };
  const char *azGoto[] = { "Goto", 0 };

@@ -2129,10 +2130,12 @@ static void tryToClone(struct callback_data *p, const char *zNewDb){
    fprintf(stderr, "Cannot create output database: %s\n",
            sqlite3_errmsg(newDb));
  }else{
+    sqlite3_exec(p->db, "PRAGMA writable_schema=ON;", 0, 0, 0);
    sqlite3_exec(newDb, "BEGIN EXCLUSIVE;", 0, 0, 0);
    tryToCloneSchema(p, newDb, "type='table'", tryToCloneData);
    tryToCloneSchema(p, newDb, "type!='table'", 0);
    sqlite3_exec(newDb, "COMMIT;", 0, 0, 0);
+    sqlite3_exec(p->db, "PRAGMA writable_schema=OFF;", 0, 0, 0);
  }
  sqlite3_close(newDb);
 }
@@ -3531,7 +3534,8 @@ static void main_init(struct callback_data *data) {
  sqlite3_config(SQLITE_CONFIG_LOG, shellLog, data);
  sqlite3_snprintf(sizeof(mainPrompt), mainPrompt,"sqlite> ");
  sqlite3_snprintf(sizeof(continuePrompt), continuePrompt,"   ...> ");
-  sqlite3_config(SQLITE_CONFIG_SINGLETHREAD);
+  sqlite3_config(SQLITE_CONFIG_MULTITHREAD);
+  sqlite3_config(SQLITE_CONFIG_WORKER_THREADS, 4);
 }

 /*
@@ -1715,6 +1715,16 @@ struct sqlite3_mem_methods {
 ** SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value
 ** that specifies the maximum size of the created heap.
 ** </dl>
+**
+** [[SQLITE_CONFIG_WORKER_THREADS]]
+** <dt>SQLITE_CONFIG_WORKER_THREADS
+** <dd>^SQLITE_CONFIG_WORKER_THREADS takes a single argument of type int.
+** It is used to set the number of background worker threads that may be
+** launched when sorting large amounts of data. A value of 0 means launch 
+** no background threads at all. The maximum number of background threads 
+** allowed is configured at build-time by the SQLITE_MAX_WORKER_THREADS 
+** pre-processor option. 
+** </dl>
 */
 #define SQLITE_CONFIG_SINGLETHREAD  1  /* nil */
 #define SQLITE_CONFIG_MULTITHREAD   2  /* nil */
@@ -1739,6 +1749,7 @@ struct sqlite3_mem_methods {
 #define SQLITE_CONFIG_SQLLOG       21  /* xSqllog, void* */
 #define SQLITE_CONFIG_MMAP_SIZE    22  /* sqlite3_int64, sqlite3_int64 */
 #define SQLITE_CONFIG_WIN32_HEAPSIZE      23  /* int nByte */
+#define SQLITE_CONFIG_WORKER_THREADS      24  /* int nWorker */

 /*
 ** CAPI3REF: Database Connection Configuration Options
@@ -6118,7 +6129,8 @@ int sqlite3_test_control(int op, ...);
 #define SQLITE_TESTCTRL_EXPLAIN_STMT            19
 #define SQLITE_TESTCTRL_NEVER_CORRUPT           20
 #define SQLITE_TESTCTRL_VDBE_COVERAGE           21
-#define SQLITE_TESTCTRL_LAST                    21
+#define SQLITE_TESTCTRL_SORTER_MMAP             22
+#define SQLITE_TESTCTRL_LAST                    22

 /*
 ** CAPI3REF: SQLite Runtime Status
@@ -422,6 +422,19 @@
 # define SQLITE_TEMP_STORE_xc 1  /* Exclude from ctime.c */
 #endif

+/*
+** If no value has been provided for SQLITE_MAX_WORKER_THREADS, or if
+** SQLITE_TEMP_STORE is set to 3 (never use temporary files), set it 
+** to zero.
+*/
+#if SQLITE_TEMP_STORE==3
+# undef SQLITE_MAX_WORKER_THREADS
+#endif
+#ifndef SQLITE_MAX_WORKER_THREADS
+# define SQLITE_MAX_WORKER_THREADS 0
+#endif
+
+
 /*
 ** GCC does not define the offsetof() macro so we'll have to do it
 ** ourselves.
@@ -788,6 +801,7 @@ typedef struct PrintfArguments PrintfArguments;
 typedef struct RowSet RowSet;
 typedef struct Savepoint Savepoint;
 typedef struct Select Select;
+typedef struct SQLiteThread SQLiteThread;
 typedef struct SelectDest SelectDest;
 typedef struct SrcList SrcList;
 typedef struct StrAccum StrAccum;
@@ -967,6 +981,7 @@ struct sqlite3 {
  int nChange;                  /* Value returned by sqlite3_changes() */
  int nTotalChange;             /* Value returned by sqlite3_total_changes() */
  int aLimit[SQLITE_N_LIMIT];   /* Limits */
+  int nMaxSorterMmap;           /* Maximum size of regions mapped by sorter */
  struct sqlite3InitInfo {      /* Information used during initialization */
    int newTnum;                /* Rootpage of table being initialized */
    u8 iDb;                     /* Which db file is being initialized */
@@ -1627,6 +1642,7 @@ struct UnpackedRecord {
  KeyInfo *pKeyInfo;  /* Collation and sort-order information */
  u16 nField;         /* Number of entries in apMem[] */
  i8 default_rc;      /* Comparison result if keys are equal */
+  u8 errCode;         /* Error detected by xRecordCompare (CORRUPT or NOMEM) */
  Mem *aMem;          /* Values */
  int r1;             /* Value to return if (lhs > rhs) */
  int r2;             /* Value to return if (rhs < lhs) */
@@ -1893,8 +1909,8 @@ struct Expr {
 #define EP_VarSelect 0x000020 /* pSelect is correlated, not constant */
 #define EP_DblQuoted 0x000040 /* token.z was originally in "..." */
 #define EP_InfixFunc 0x000080 /* True for an infix function: LIKE, GLOB, etc */
-#define EP_Collate   0x000100 /* Tree contains a TK_COLLATE opeartor */
-      /* unused      0x000200 */
+#define EP_Collate   0x000100 /* Tree contains a TK_COLLATE operator */
+#define EP_Generic   0x000200 /* Ignore COLLATE or affinity on this tree */
 #define EP_IntValue  0x000400 /* Integer value contained in u.iValue */
 #define EP_xIsSelect 0x000800 /* x.pSelect is valid (otherwise x.pList is) */
 #define EP_Skip      0x001000 /* COLLATE, AS, or UNLIKELY */
@@ -1958,7 +1974,6 @@ struct Expr {
 */
 struct ExprList {
  int nExpr;             /* Number of expressions on the list */
-  int iECursor;          /* VDBE Cursor associated with this ExprList */
  struct ExprList_item { /* For each expression in the list */
    Expr *pExpr;            /* The list of expressions */
    char *zName;            /* Token associated with this expression */
@@ -2182,7 +2197,7 @@ struct Select {
  u8 op;                 /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */
  u16 selFlags;          /* Various SF_* values */
  int iLimit, iOffset;   /* Memory registers holding LIMIT & OFFSET counters */
-  int addrOpenEphm[3];   /* OP_OpenEphem opcodes related to this select */
+  int addrOpenEphm[2];   /* OP_OpenEphem opcodes related to this select */
  u64 nSelectRow;        /* Estimated number of result rows */
  SrcList *pSrc;         /* The FROM clause */
  Expr *pWhere;          /* The WHERE clause */
@@ -2206,9 +2221,9 @@ struct Select {
 #define SF_UsesEphemeral   0x0008  /* Uses the OpenEphemeral opcode */
 #define SF_Expanded        0x0010  /* sqlite3SelectExpand() called on this */
 #define SF_HasTypeInfo     0x0020  /* FROM subqueries have Table metadata */
-#define SF_UseSorter       0x0040  /* Sort using a sorter */
+                    /*     0x0040  NOT USED */
 #define SF_Values          0x0080  /* Synthesized from VALUES clause */
-#define SF_Materialize     0x0100  /* NOT USED */
+                    /*     0x0100  NOT USED */
 #define SF_NestedFrom      0x0200  /* Part of a parenthesized FROM clause */
 #define SF_MaybeConvert    0x0400  /* Need convertCompoundSelectToSubquery() */
 #define SF_Recursive       0x0800  /* The recursive part of a recursive CTE */
@@ -2261,13 +2276,15 @@ struct Select {
 **                     starting with pDest->iSdst.
 **
 **     SRT_Table       Store results in temporary table pDest->iSDParm.
-**                     This is like SRT_EphemTab except that the table
-**                     is assumed to already be open.
+**     SRT_Fifo        This is like SRT_EphemTab except that the table
+**                     is assumed to already be open.  SRT_Fifo has
+**                     the additional property of being able to ignore
+**                     the ORDER BY clause.
 **
-**     SRT_DistTable   Store results in a temporary table pDest->iSDParm.
+**     SRT_DistFifo    Store results in a temporary table pDest->iSDParm.
 **                     But also use temporary table pDest->iSDParm+1 as
 **                     a record of all prior results and ignore any duplicate
-**                     rows.  Name means:  "Distinct Table".
+**                     rows.  Name means:  "Distinct Fifo".
 **
 **     SRT_Queue       Store results in priority queue pDest->iSDParm (really
 **                     an index).  Append a sequence number so that all entries
@@ -2281,19 +2298,20 @@ struct Select {
 #define SRT_Except       2  /* Remove result from a UNION index */
 #define SRT_Exists       3  /* Store 1 if the result is not empty */
 #define SRT_Discard      4  /* Do not save the results anywhere */
+#define SRT_Fifo         5  /* Store result as data with an automatic rowid */
+#define SRT_DistFifo     6  /* Like SRT_Fifo, but unique results only */
+#define SRT_Queue        7  /* Store result in an queue */
+#define SRT_DistQueue    8  /* Like SRT_Queue, but unique results only */

 /* The ORDER BY clause is ignored for all of the above */
-#define IgnorableOrderby(X) ((X->eDest)<=SRT_Discard)
+#define IgnorableOrderby(X) ((X->eDest)<=SRT_DistQueue)

-#define SRT_Output       5  /* Output each row of result */
-#define SRT_Mem          6  /* Store result in a memory cell */
-#define SRT_Set          7  /* Store results as keys in an index */
-#define SRT_EphemTab     8  /* Create transient tab and store like SRT_Table */
-#define SRT_Coroutine    9  /* Generate a single row of result */
-#define SRT_Table       10  /* Store result as data with an automatic rowid */
-#define SRT_DistTable   11  /* Like SRT_Table, but unique results only */
-#define SRT_Queue       12  /* Store result in an queue */
-#define SRT_DistQueue   13  /* Like SRT_Queue, but unique results only */
+#define SRT_Output       9  /* Output each row of result */
+#define SRT_Mem         10  /* Store result in a memory cell */
+#define SRT_Set         11  /* Store results as keys in an index */
+#define SRT_EphemTab    12  /* Create transient tab and store like SRT_Table */
+#define SRT_Coroutine   13  /* Generate a single row of result */
+#define SRT_Table       14  /* Store result as data with an automatic rowid */

 /*
 ** An instance of this object describes where to put of the results of
@@ -2391,8 +2409,6 @@ struct Parse {
  u8 checkSchema;      /* Causes schema cookie check after an error */
  u8 nested;           /* Number of nested calls to the parser/code generator */
  u8 nTempReg;         /* Number of temporary registers in aTempReg[] */
-  u8 nColCache;        /* Number of entries in aColCache[] */
-  u8 iColCache;        /* Next entry in aColCache[] to replace */
  u8 isMultiWrite;     /* True if statement may modify/insert multiple rows */
  u8 mayAbort;         /* True if statement may throw an ABORT exception */
  u8 hasCompound;      /* Need to invoke convertCompoundSelectToSubquery() */
@@ -2683,6 +2699,7 @@ struct Sqlite3Config {
  int nPage;                        /* Number of pages in pPage[] */
  int mxParserStack;                /* maximum depth of the parser stack */
  int sharedCacheEnabled;           /* true if shared-cache mode enabled */
+  int nWorker;                      /* Number of worker threads to use */
  /* The above might be initialized to non-zero.  The following need to always
  ** initially be zero, however. */
  int isInit;                       /* True after initialization has finished */
@@ -3291,7 +3308,7 @@ int sqlite3ReadSchema(Parse *pParse);
 CollSeq *sqlite3FindCollSeq(sqlite3*,u8 enc, const char*,int);
 CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char*zName);
 CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr);
-Expr *sqlite3ExprAddCollateToken(Parse *pParse, Expr*, Token*);
+Expr *sqlite3ExprAddCollateToken(Parse *pParse, Expr*, const Token*);
 Expr *sqlite3ExprAddCollateString(Parse*,Expr*,const char*);
 Expr *sqlite3ExprSkipCollate(Expr*);
 int sqlite3CheckCollSeq(Parse *, CollSeq *);
@@ -3632,4 +3649,19 @@ SQLITE_EXTERN void (*sqlite3IoTrace)(const char*,...);
 #define MEMTYPE_PCACHE     0x08  /* Page cache allocations */
 #define MEMTYPE_DB         0x10  /* Uses sqlite3DbMalloc, not sqlite_malloc */

+/*
+** Threading interface
+*/
+#if SQLITE_MAX_WORKER_THREADS>0
+int sqlite3ThreadCreate(SQLiteThread**,void*(*)(void*),void*);
+int sqlite3ThreadJoin(SQLiteThread*, void**);
+#endif
+
+/*
+** Win32 interface
+*/
+#if SQLITE_OS_WIN
+  DWORD sqlite3Win32Wait(HANDLE hObject);
+#endif
+
 #endif /* _SQLITEINT_H_ */
@@ -2703,6 +2703,46 @@ bad_args:
  return TCL_ERROR;
 }

+/*
+** Usage: add_test_utf16bin_collate <db ptr>
+**
+** Add a utf-16 collation sequence named "utf16bin" to the database
+** handle. This collation sequence compares arguments in the same way as the
+** built-in collation "binary".
+*/
+static int test_utf16bin_collate_func(
+  void *pCtx, 
+  int nA, const void *zA,
+  int nB, const void *zB
+){
+  int nCmp = (nA>nB ? nB : nA);
+  int res = memcmp(zA, zB, nCmp);
+  if( res==0 ) res = nA - nB;
+  return res;
+}
+static int test_utf16bin_collate(
+  void * clientData,
+  Tcl_Interp *interp,
+  int objc,
+  Tcl_Obj *CONST objv[]
+){
+  sqlite3 *db;
+  int rc;
+
+  if( objc!=2 ) goto bad_args;
+  if( getDbPointer(interp, Tcl_GetString(objv[1]), &db) ) return TCL_ERROR;
+
+  rc = sqlite3_create_collation(db, "utf16bin", SQLITE_UTF16, 0, 
+      test_utf16bin_collate_func
+  );
+  if( sqlite3TestErrCode(interp, db, rc) ) return TCL_ERROR;
+  return TCL_OK;
+
+bad_args:
+  Tcl_WrongNumArgs(interp, 1, objv, "DB");
+  return TCL_ERROR;
+}
+
 /*
 ** When the collation needed callback is invoked, record the name of 
 ** the requested collating function here.  The recorded name is linked
@@ -5844,6 +5884,7 @@ static int test_test_control(
    int i;
  } aVerb[] = {
    { "SQLITE_TESTCTRL_LOCALTIME_FAULT", SQLITE_TESTCTRL_LOCALTIME_FAULT }, 
+    { "SQLITE_TESTCTRL_SORTER_MMAP", SQLITE_TESTCTRL_SORTER_MMAP }, 
  };
  int iVerb;
  int iFlag;
@@ -5871,6 +5912,19 @@ static int test_test_control(
      sqlite3_test_control(SQLITE_TESTCTRL_LOCALTIME_FAULT, val);
      break;
    }
+
+    case SQLITE_TESTCTRL_SORTER_MMAP: {
+      int val;
+      sqlite3 *db;
+      if( objc!=4 ){
+        Tcl_WrongNumArgs(interp, 2, objv, "DB LIMIT");
+        return TCL_ERROR;
+      }
+      if( getDbPointer(interp, Tcl_GetString(objv[2]), &db) ) return TCL_ERROR;
+      if( Tcl_GetIntFromObj(interp, objv[3], &val) ) return TCL_ERROR;
+      sqlite3_test_control(SQLITE_TESTCTRL_SORTER_MMAP, db, val);
+      break;
+    }
  }

  Tcl_ResetResult(interp);
@@ -6481,6 +6535,7 @@ int Sqlitetest1_Init(Tcl_Interp *interp){
     { "add_test_collate",        test_collate, 0            },
     { "add_test_collate_needed", test_collate_needed, 0     },
     { "add_test_function",       test_function, 0           },
+     { "add_test_utf16bin_collate",    test_utf16bin_collate, 0        },
 #endif
     { "sqlite3_test_errstr",     test_errstr, 0             },
     { "tcl_variable_type",       tcl_variable_type, 0       },
@@ -99,6 +99,12 @@ static void set_options(Tcl_Interp *interp){
  Tcl_SetVar2(interp, "sqlite_options", "mmap", "0", TCL_GLOBAL_ONLY);
 #endif

+#if SQLITE_MAX_WORKER_THREADS>0
+  Tcl_SetVar2(interp, "sqlite_options", "worker_threads", "1", TCL_GLOBAL_ONLY);
+#else
+  Tcl_SetVar2(interp, "sqlite_options", "worker_threads", "0", TCL_GLOBAL_ONLY);
+#endif
+
 #if 1 /* def SQLITE_MEMDEBUG */
  Tcl_SetVar2(interp, "sqlite_options", "memdebug", "1", TCL_GLOBAL_ONLY);
 #else
@@ -1253,6 +1253,32 @@ static int test_config_cis(
  return TCL_OK;
 }

+/*
+** Usage:    sqlite3_config_worker_threads N
+*/
+static int test_config_worker_threads(
+  void * clientData, 
+  Tcl_Interp *interp,
+  int objc,
+  Tcl_Obj *CONST objv[]
+){
+  int rc;
+  int nThread;
+
+  if( objc!=2 ){
+    Tcl_WrongNumArgs(interp, 1, objv, "N");
+    return TCL_ERROR;
+  }
+  if( Tcl_GetIntFromObj(interp, objv[1], &nThread) ){
+    return TCL_ERROR;
+  }
+
+  rc = sqlite3_config(SQLITE_CONFIG_WORKER_THREADS, nThread);
+  Tcl_SetResult(interp, (char *)sqlite3ErrName(rc), TCL_VOLATILE);
+
+  return TCL_OK;
+}
+
 /*
 ** Usage:    sqlite3_dump_memsys3  FILENAME
 **           sqlite3_dump_memsys5  FILENAME
@@ -1506,6 +1532,7 @@ int Sqlitetest_malloc_Init(Tcl_Interp *interp){
     { "sqlite3_config_error",       test_config_error             ,0 },
     { "sqlite3_config_uri",         test_config_uri               ,0 },
     { "sqlite3_config_cis",         test_config_cis               ,0 },
+     { "sqlite3_config_worker_threads", test_config_worker_threads ,0 },
     { "sqlite3_db_config_lookaside",test_db_config_lookaside      ,0 },
     { "sqlite3_dump_memsys3",       test_dump_memsys3             ,3 },
     { "sqlite3_dump_memsys5",       test_dump_memsys3             ,5 },
@@ -67,6 +67,11 @@
 **   test_syscall list
 **     Return a list of all system calls. The list is constructed using
 **     the xNextSystemCall() VFS method.
+**
+**   test_syscall pagesize PGSZ
+**     If PGSZ is a power of two greater than 256, install a wrapper around
+**     OS function getpagesize() that reports the system page size as PGSZ.
+**     Or, if PGSZ is less than zero, remove any wrapper already installed.
 */

 #include "sqliteInt.h"
@@ -89,7 +94,9 @@ static struct TestSyscallGlobal {
  int bPersist;                   /* 1 for persistent errors, 0 for transient */
  int nCount;                     /* Fail after this many more calls */
  int nFail;                      /* Number of failures that have occurred */
-} gSyscall = { 0, 0 };
+  int pgsz;
+  sqlite3_syscall_ptr orig_getpagesize;
+} gSyscall = { 0, 0, 0, 0, 0 };

 static int ts_open(const char *, int, int);
 static int ts_close(int fd);
@@ -650,6 +657,45 @@ static int test_syscall_defaultvfs(
  return TCL_OK;
 }

+static int ts_getpagesize(void){
+  return gSyscall.pgsz;
+}
+
+static int test_syscall_pagesize(
+  void * clientData,
+  Tcl_Interp *interp,
+  int objc,
+  Tcl_Obj *CONST objv[]
+){
+  sqlite3_vfs *pVfs = sqlite3_vfs_find(0);
+  int pgsz;
+  if( objc!=3 ){
+    Tcl_WrongNumArgs(interp, 2, objv, "PGSZ");
+    return TCL_ERROR;
+  }
+  if( Tcl_GetIntFromObj(interp, objv[2], &pgsz) ){
+    return TCL_ERROR;
+  }
+
+  if( pgsz<0 ){
+    if( gSyscall.orig_getpagesize ){
+      pVfs->xSetSystemCall(pVfs, "getpagesize", gSyscall.orig_getpagesize);
+    }
+  }else{
+    if( pgsz<512 || (pgsz & (pgsz-1)) ){
+      Tcl_AppendResult(interp, "pgsz out of range", 0);
+      return TCL_ERROR;
+    }
+    gSyscall.orig_getpagesize = pVfs->xGetSystemCall(pVfs, "getpagesize");
+    gSyscall.pgsz = pgsz;
+    pVfs->xSetSystemCall(
+        pVfs, "getpagesize", (sqlite3_syscall_ptr)ts_getpagesize
+    );
+  }
+
+  return TCL_OK;
+}
+
 static int test_syscall(
  void * clientData,
  Tcl_Interp *interp,
@@ -668,6 +714,7 @@ static int test_syscall(
    { "exists",     test_syscall_exists },
    { "list",       test_syscall_list },
    { "defaultvfs", test_syscall_defaultvfs },
+    { "pagesize",   test_syscall_pagesize },
    { 0, 0 }
  };
  int iCmd;
@@ -0,0 +1,220 @@
+/*
+** 2012 July 21
+**
+** 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 presents a simple cross-platform threading interface for
+** use internally by SQLite.
+**
+** A "thread" can be created using sqlite3ThreadCreate().  This thread
+** runs independently of its creator until it is joined using
+** sqlite3ThreadJoin(), at which point it terminates.
+**
+** Threads do not have to be real.  It could be that the work of the
+** "thread" is done by the main thread at either the sqlite3ThreadCreate()
+** or sqlite3ThreadJoin() call.  This is, in fact, what happens in
+** single threaded systems.  Nothing in SQLite requires multiple threads.
+** This interface exists so that applications that want to take advantage
+** of multiple cores can do so, while also allowing applications to stay
+** single-threaded if desired.
+*/
+#include "sqliteInt.h"
+
+#if SQLITE_MAX_WORKER_THREADS>0
+
+/********************************* Unix Pthreads ****************************/
+#if SQLITE_OS_UNIX && defined(SQLITE_MUTEX_PTHREADS) && SQLITE_THREADSAFE>0
+
+#define SQLITE_THREADS_IMPLEMENTED 1  /* Prevent the single-thread code below */
+#include <pthread.h>
+
+/* A running thread */
+struct SQLiteThread {
+  pthread_t tid;
+  int done;
+  void *pOut;
+};
+
+/* Create a new thread */
+int sqlite3ThreadCreate(
+  SQLiteThread **ppThread,  /* OUT: Write the thread object here */
+  void *(*xTask)(void*),    /* Routine to run in a separate thread */
+  void *pIn                 /* Argument passed into xTask() */
+){
+  SQLiteThread *p;
+
+  assert( ppThread!=0 );
+  assert( xTask!=0 );
+  *ppThread = 0;
+  p = sqlite3Malloc(sizeof(*p));
+  if( p==0 ) return SQLITE_NOMEM;
+  memset(p, 0, sizeof(*p));
+  if( sqlite3GlobalConfig.bCoreMutex==0
+    || pthread_create(&p->tid, 0, xTask, pIn)!=0 
+  ){
+    p->done = 1;
+    p->pOut = xTask(pIn);
+  }
+  *ppThread = p;
+  return SQLITE_OK;
+}
+
+/* Get the results of the thread */
+int sqlite3ThreadJoin(SQLiteThread *p, void **ppOut){
+  int rc;
+
+  assert( ppOut!=0 );
+  if( p==0 ) return SQLITE_NOMEM;
+  if( p->done ){
+    *ppOut = p->pOut;
+    rc = SQLITE_OK;
+  }else{
+    rc = pthread_join(p->tid, ppOut);
+  }
+  sqlite3_free(p);
+  return rc ? SQLITE_ERROR : SQLITE_OK;
+}
+
+#endif /* SQLITE_OS_UNIX && defined(SQLITE_MUTEX_PTHREADS) */
+/******************************** End Unix Pthreads *************************/
+
+
+/********************************* Win32 Threads ****************************/
+#if SQLITE_OS_WIN && !SQLITE_OS_WINRT && SQLITE_THREADSAFE>0
+
+#define SQLITE_THREADS_IMPLEMENTED 1  /* Prevent the single-thread code below */
+#include <process.h>
+
+/* A running thread */
+struct SQLiteThread {
+  uintptr_t tid;           /* The thread handle */
+  void *(*xTask)(void*);   /* The routine to run as a thread */
+  void *pIn;               /* Argument to xTask */
+  void *pResult;           /* Result of xTask */
+};
+
+/* Thread procedure Win32 compatibility shim */
+static void sqlite3ThreadProc(
+  void *pArg  /* IN: Pointer to the SQLiteThread structure */
+){
+  SQLiteThread *p = (SQLiteThread *)pArg;
+
+  assert( p!=0 );
+  assert( p->xTask!=0 );
+  p->pResult = p->xTask(p->pIn);
+  _endthread();
+}
+
+/* Create a new thread */
+int sqlite3ThreadCreate(
+  SQLiteThread **ppThread,  /* OUT: Write the thread object here */
+  void *(*xTask)(void*),    /* Routine to run in a separate thread */
+  void *pIn                 /* Argument passed into xTask() */
+){
+  SQLiteThread *p;
+
+  assert( ppThread!=0 );
+  assert( xTask!=0 );
+  *ppThread = 0;
+  p = sqlite3Malloc(sizeof(*p));
+  if( p==0 ) return SQLITE_NOMEM;
+  if( sqlite3GlobalConfig.bCoreMutex==0 ){
+    memset(p, 0, sizeof(*p));
+  }else{
+    p->xTask = xTask;
+    p->pIn = pIn;
+    p->tid = _beginthread(sqlite3ThreadProc, 0, p);
+    if( p->tid==(uintptr_t)-1 ){
+      memset(p, 0, sizeof(*p));
+    }
+  }
+  if( p->xTask==0 ){
+    p->pResult = xTask(pIn);
+  }
+  *ppThread = p;
+  return SQLITE_OK;
+}
+
+/* Get the results of the thread */
+int sqlite3ThreadJoin(SQLiteThread *p, void **ppOut){
+  DWORD rc;
+
+  assert( ppOut!=0 );
+  if( p==0 ) return SQLITE_NOMEM;
+  if( p->xTask==0 ){
+    rc = WAIT_OBJECT_0;
+  }else{
+    rc = sqlite3Win32Wait((HANDLE)p->tid);
+    assert( rc!=WAIT_IO_COMPLETION );
+  }
+  if( rc==WAIT_OBJECT_0 ) *ppOut = p->pResult;
+  sqlite3_free(p);
+  return (rc==WAIT_OBJECT_0) ? SQLITE_OK : SQLITE_ERROR;
+}
+
+#endif /* SQLITE_OS_WIN && !SQLITE_OS_WINRT */
+/******************************** End Win32 Threads *************************/
+
+
+/********************************* Single-Threaded **************************/
+#ifndef SQLITE_THREADS_IMPLEMENTED
+/*
+** This implementation does not actually create a new thread.  It does the
+** work of the thread in the main thread, when either the thread is created
+** or when it is joined
+*/
+
+/* A running thread */
+struct SQLiteThread {
+  void *(*xTask)(void*);   /* The routine to run as a thread */
+  void *pIn;               /* Argument to xTask */
+  void *pResult;           /* Result of xTask */
+};
+
+/* Create a new thread */
+int sqlite3ThreadCreate(
+  SQLiteThread **ppThread,  /* OUT: Write the thread object here */
+  void *(*xTask)(void*),    /* Routine to run in a separate thread */
+  void *pIn                 /* Argument passed into xTask() */
+){
+  SQLiteThread *p;
+
+  assert( ppThread!=0 );
+  assert( xTask!=0 );
+  *ppThread = 0;
+  p = sqlite3Malloc(sizeof(*p));
+  if( p==0 ) return SQLITE_NOMEM;
+  if( (SQLITE_PTR_TO_INT(p)/17)&1 ){
+    p->xTask = xTask;
+    p->pIn = pIn;
+  }else{
+    p->xTask = 0;
+    p->pResult = xTask(pIn);
+  }
+  *ppThread = p;
+  return SQLITE_OK;
+}
+
+/* Get the results of the thread */
+int sqlite3ThreadJoin(SQLiteThread *p, void **ppOut){
+  assert( ppOut!=0 );
+  if( p==0 ) return SQLITE_NOMEM;
+  if( p->xTask ){
+    *ppOut = p->xTask(p->pIn);
+  }else{
+    *ppOut = p->pResult;
+  }
+  sqlite3_free(p);
+  return SQLITE_OK;
+}
+
+#endif /* !defined(SQLITE_THREADS_IMPLEMENTED) */
+/****************************** End Single-Threaded *************************/
+#endif /* SQLITE_MAX_WORKER_THREADS>0 */
@@ -566,7 +566,7 @@ void sqlite3DropTriggerPtr(Parse *pParse, Trigger *pTrigger){
  assert( pTable!=0 );
  if( (v = sqlite3GetVdbe(pParse))!=0 ){
    int base;
-    static const int iLn = __LINE__+2;
+    static const int iLn = VDBE_OFFSET_LINENO(2);
    static const VdbeOpList dropTrigger[] = {
      { OP_Rewind,     0, ADDR(9),  0},
      { OP_String8,    0, 1,        0}, /* 1 */
@@ -310,6 +310,29 @@ void sqlite3ValueApplyAffinity(
  applyAffinity((Mem *)pVal, affinity, enc);
 }

+/*
+** Return the numeric type for pMem, either MEM_Int or MEM_Real or both or
+** none.  
+**
+** Unlike applyNumericAffinity(), this routine does not modify pMem->flags.
+** But it does set pMem->r and pMem->u.i appropriately.
+*/
+static u16 numericType(Mem *pMem){
+  if( pMem->flags & (MEM_Int|MEM_Real) ){
+    return pMem->flags & (MEM_Int|MEM_Real);
+  }
+  if( pMem->flags & (MEM_Str|MEM_Blob) ){
+    if( sqlite3AtoF(pMem->z, &pMem->r, pMem->n, pMem->enc)==0 ){
+      return 0;
+    }
+    if( sqlite3Atoi64(pMem->z, &pMem->u.i, pMem->n, pMem->enc)==SQLITE_OK ){
+      return MEM_Int;
+    }
+    return MEM_Real;
+  }
+  return 0;
+}
+
 #ifdef SQLITE_DEBUG
 /*
 ** Write a nice string representation of the contents of cell pMem
@@ -1080,10 +1103,11 @@ case OP_Variable: {            /* out2-prerelease */
 /* Opcode: Move P1 P2 P3 * *
 ** Synopsis:  r[P2@P3]=r[P1@P3]
 **
-** Move the values in register P1..P1+P3 over into
-** registers P2..P2+P3.  Registers P1..P1+P3 are
+** Move the P3 values in register P1..P1+P3-1 over into
+** registers P2..P2+P3-1.  Registers P1..P1+P3-1 are
 ** left holding a NULL.  It is an error for register ranges
-** P1..P1+P3 and P2..P2+P3 to overlap.
+** P1..P1+P3-1 and P2..P2+P3-1 to overlap.  It is an error
+** for P3 to be less than 1.
 */
 case OP_Move: {
  char *zMalloc;   /* Holding variable for allocated memory */
@@ -1094,7 +1118,7 @@ case OP_Move: {
  n = pOp->p3;
  p1 = pOp->p1;
  p2 = pOp->p2;
-  assert( n>=0 && p1>0 && p2>0 );
+  assert( n>0 && p1>0 && p2>0 );
  assert( p1+n<=p2 || p2+n<=p1 );

  pIn1 = &aMem[p1];
@@ -1118,7 +1142,7 @@ case OP_Move: {
    REGISTER_TRACE(p2++, pOut);
    pIn1++;
    pOut++;
-  }while( n-- );
+  }while( --n );
  break;
 }

@@ -1350,20 +1374,22 @@ case OP_Multiply:              /* same as TK_STAR, in1, in2, out3 */
 case OP_Divide:                /* same as TK_SLASH, in1, in2, out3 */
 case OP_Remainder: {           /* same as TK_REM, in1, in2, out3 */
  char bIntint;   /* Started out as two integer operands */
-  int flags;      /* Combined MEM_* flags from both inputs */
+  u16 flags;      /* Combined MEM_* flags from both inputs */
+  u16 type1;      /* Numeric type of left operand */
+  u16 type2;      /* Numeric type of right operand */
  i64 iA;         /* Integer value of left operand */
  i64 iB;         /* Integer value of right operand */
  double rA;      /* Real value of left operand */
  double rB;      /* Real value of right operand */

  pIn1 = &aMem[pOp->p1];
-  applyNumericAffinity(pIn1);
+  type1 = numericType(pIn1);
  pIn2 = &aMem[pOp->p2];
-  applyNumericAffinity(pIn2);
+  type2 = numericType(pIn2);
  pOut = &aMem[pOp->p3];
  flags = pIn1->flags | pIn2->flags;
  if( (flags & MEM_Null)!=0 ) goto arithmetic_result_is_null;
-  if( (pIn1->flags & pIn2->flags & MEM_Int)==MEM_Int ){
+  if( (type1 & type2 & MEM_Int)!=0 ){
    iA = pIn1->u.i;
    iB = pIn2->u.i;
    bIntint = 1;
@@ -1419,7 +1445,7 @@ fp_math:
    }
    pOut->r = rB;
    MemSetTypeFlag(pOut, MEM_Real);
-    if( (flags & MEM_Real)==0 && !bIntint ){
+    if( ((type1|type2)&MEM_Real)==0 && !bIntint ){
      sqlite3VdbeIntegerAffinity(pOut);
    }
 #endif
@@ -1995,6 +2021,7 @@ case OP_Permutation: {
 }

 /* Opcode: Compare P1 P2 P3 P4 P5
+** Synopsis: r[P1@P3] <-> r[P2@P3]
 **
 ** Compare two vectors of registers in reg(P1)..reg(P1+P3-1) (call this
 ** vector "A") and in reg(P2)..reg(P2+P3-1) ("B").  Save the result of
@@ -3330,6 +3357,7 @@ case OP_OpenEphemeral: {
  pCx = allocateCursor(p, pOp->p1, pOp->p2, -1, 1);
  if( pCx==0 ) goto no_mem;
  pCx->nullRow = 1;
+  pCx->isEphemeral = 1;
  rc = sqlite3BtreeOpen(db->pVfs, 0, db, &pCx->pBt, 
                        BTREE_OMIT_JOURNAL | BTREE_SINGLE | pOp->p5, vfsFlags);
  if( rc==SQLITE_OK ){
@@ -3362,11 +3390,15 @@ case OP_OpenEphemeral: {
  break;
 }

-/* Opcode: SorterOpen P1 P2 * P4 *
+/* Opcode: SorterOpen P1 P2 P3 P4 *
 **
 ** This opcode works like OP_OpenEphemeral except that it opens
 ** a transient index that is specifically designed to sort large
 ** tables using an external merge-sort algorithm.
+**
+** If argument P3 is non-zero, then it indicates that the sorter may
+** assume that a stable sort considering the first P3 fields of each
+** key is sufficient to produce the required results.
 */
 case OP_SorterOpen: {
  VdbeCursor *pCx;
@@ -3378,7 +3410,25 @@ case OP_SorterOpen: {
  pCx->pKeyInfo = pOp->p4.pKeyInfo;
  assert( pCx->pKeyInfo->db==db );
  assert( pCx->pKeyInfo->enc==ENC(db) );
-  rc = sqlite3VdbeSorterInit(db, pCx);
+  rc = sqlite3VdbeSorterInit(db, pOp->p3, pCx);
+  break;
+}
+
+/* Opcode: SequenceTest P1 P2 * * *
+** Synopsis: if( cursor[P1].ctr++ ) pc = P2
+**
+** P1 is a sorter cursor. If the sequence counter is currently zero, jump
+** to P2. Regardless of whether or not the jump is taken, increment the
+** the sequence value.
+*/
+case OP_SequenceTest: {
+  VdbeCursor *pC;
+  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
+  pC = p->apCsr[pOp->p1];
+  assert( pC->pSorter );
+  if( (pC->seqCount++)==0 ){
+    pc = pOp->p2 - 1;
+  }
  break;
 }

@@ -3820,7 +3870,7 @@ case OP_NotExists: {        /* jump, in3 */
 }

 /* Opcode: Sequence P1 P2 * * *
-** Synopsis: r[P2]=rowid
+** Synopsis: r[P2]=cursor[P1].ctr++
 **
 ** Find the next available sequence number for cursor P1.
 ** Write the sequence number into register P2.
@@ -4511,6 +4561,7 @@ case OP_SorterNext: {  /* jump */

  pC = p->apCsr[pOp->p1];
  assert( isSorter(pC) );
+  res = 0;
  rc = sqlite3VdbeSorterNext(db, pC, &res);
  goto next_tail;
 case OP_PrevIfOpen:    /* jump */
@@ -4869,6 +4920,29 @@ case OP_Clear: {
  break;
 }

+/* Opcode: ResetSorter P1 * * * *
+**
+** Delete all contents from the ephemeral table or sorter
+** that is open on cursor P1.
+**
+** This opcode only works for cursors used for sorting and
+** opened with OP_OpenEphemeral or OP_SorterOpen.
+*/
+case OP_ResetSorter: {
+  VdbeCursor *pC;
+ 
+  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
+  pC = p->apCsr[pOp->p1];
+  assert( pC!=0 );
+  if( pC->pSorter ){
+    sqlite3VdbeSorterReset(db, pC->pSorter);
+  }else{
+    assert( pC->isEphemeral );
+    rc = sqlite3BtreeClearTableOfCursor(pC->pCursor);
+  }
+  break;
+}
+
 /* Opcode: CreateTable P1 P2 * * *
 ** Synopsis: r[P2]=root iDb=P1
 **
@@ -5877,7 +5951,7 @@ case OP_VOpen: {

 #ifndef SQLITE_OMIT_VIRTUALTABLE
 /* Opcode: VFilter P1 P2 P3 P4 *
-** Synopsis: iPlan=r[P3] zPlan='P4'
+** Synopsis: iplan=r[P3] zplan='P4'
 **
 ** P1 is a cursor opened using VOpen.  P2 is an address to jump to if
 ** the filtered result set is empty.
@@ -211,10 +211,10 @@ void sqlite3VdbeSetVarmask(Vdbe*, int);
 #endif

 void sqlite3VdbeRecordUnpack(KeyInfo*,int,const void*,UnpackedRecord*);
-int sqlite3VdbeRecordCompare(int,const void*,const UnpackedRecord*,int);
+int sqlite3VdbeRecordCompare(int,const void*,UnpackedRecord*,int);
 UnpackedRecord *sqlite3VdbeAllocUnpackedRecord(KeyInfo *, char *, int, char **);

-typedef int (*RecordCompare)(int,const void*,const UnpackedRecord*,int);
+typedef int (*RecordCompare)(int,const void*,UnpackedRecord*,int);
 RecordCompare sqlite3VdbeFindCompare(UnpackedRecord*);

 #ifndef SQLITE_OMIT_TRIGGER
@@ -272,11 +272,13 @@ void sqlite3VdbeLinkSubProgram(Vdbe *, SubProgram *);
 # define VdbeCoverageIf(v,x) if(x)sqlite3VdbeSetLineNumber(v,__LINE__)
 # define VdbeCoverageAlwaysTaken(v) sqlite3VdbeSetLineNumber(v,2);
 # define VdbeCoverageNeverTaken(v) sqlite3VdbeSetLineNumber(v,1);
+# define VDBE_OFFSET_LINENO(x) (__LINE__+x)
 #else
 # define VdbeCoverage(v)
 # define VdbeCoverageIf(v,x)
 # define VdbeCoverageAlwaysTaken(v)
 # define VdbeCoverageNeverTaken(v)
+# define VDBE_OFFSET_LINENO(x) 0
 #endif

 #endif
@@ -72,6 +72,7 @@ struct VdbeCursor {
  u8 nullRow;           /* True if pointing to a row with no data */
  u8 rowidIsValid;      /* True if lastRowid is valid */
  u8 deferredMoveto;    /* A call to sqlite3BtreeMoveto() is needed */
+  Bool isEphemeral:1;   /* True for an ephemeral table */
  Bool useRandomRowid:1;/* Generate new record numbers semi-randomly */
  Bool isTable:1;       /* True if a table requiring integer keys */
  Bool isOrdered:1;     /* True if the underlying table is BTREE_UNORDERED */
@@ -391,7 +392,7 @@ u32 sqlite3VdbeSerialGet(const unsigned char*, u32, Mem*);
 void sqlite3VdbeDeleteAuxData(Vdbe*, int, int);

 int sqlite2BtreeKeyCompare(BtCursor *, const void *, int, int, int *);
-int sqlite3VdbeIdxKeyCompare(VdbeCursor*,const UnpackedRecord*,int*);
+int sqlite3VdbeIdxKeyCompare(VdbeCursor*,UnpackedRecord*,int*);
 int sqlite3VdbeIdxRowid(sqlite3*, BtCursor *, i64 *);
 int sqlite3MemCompare(const Mem*, const Mem*, const CollSeq*);
 int sqlite3VdbeExec(Vdbe*);
@@ -436,7 +437,8 @@ void sqlite3VdbeFrameDelete(VdbeFrame*);
 int sqlite3VdbeFrameRestore(VdbeFrame *);
 int sqlite3VdbeTransferError(Vdbe *p);

-int sqlite3VdbeSorterInit(sqlite3 *, VdbeCursor *);
+int sqlite3VdbeSorterInit(sqlite3 *, int, VdbeCursor *);
+void sqlite3VdbeSorterReset(sqlite3 *, VdbeSorter *);
 void sqlite3VdbeSorterClose(sqlite3 *, VdbeCursor *);
 int sqlite3VdbeSorterRowkey(const VdbeCursor *, Mem *);
 int sqlite3VdbeSorterNext(sqlite3 *, const VdbeCursor *, int *);
@@ -783,7 +783,9 @@ void sqlite3VdbeChangeP4(Vdbe *p, int addr, const char *zP4, int n){
    addr = p->nOp - 1;
  }
  pOp = &p->aOp[addr];
-  assert( pOp->p4type==P4_NOTUSED || pOp->p4type==P4_INT32 );
+  assert( pOp->p4type==P4_NOTUSED
+       || pOp->p4type==P4_INT32
+       || pOp->p4type==P4_KEYINFO );
  freeP4(db, pOp->p4type, pOp->p4.p);
  pOp->p4.p = 0;
  if( n==P4_INT32 ){
@@ -2733,7 +2735,7 @@ int sqlite3VdbeCursorMoveto(VdbeCursor *p){
    if( rc ) return rc;
    if( hasMoved ){
      p->cacheStatus = CACHE_STALE;
-      p->nullRow = 1;
+      if( hasMoved==2 ) p->nullRow = 1;
    }
  }
  return SQLITE_OK;
@@ -3227,7 +3229,8 @@ static int vdbeRecordCompareDebug(
 static int vdbeCompareMemString(
  const Mem *pMem1,
  const Mem *pMem2,
-  const CollSeq *pColl
+  const CollSeq *pColl,
+  u8 *prcErr                      /* If an OOM occurs, set to SQLITE_NOMEM */
 ){
  if( pMem1->enc==pColl->enc ){
    /* The strings are already in the correct encoding.  Call the
@@ -3250,6 +3253,7 @@ static int vdbeCompareMemString(
    rc = pColl->xCmp(pColl->pUser, n1, v1, n2, v2);
    sqlite3VdbeMemRelease(&c1);
    sqlite3VdbeMemRelease(&c2);
+    if( (v1==0 || v2==0) && prcErr ) *prcErr = SQLITE_NOMEM;
    return rc;
  }
 }
@@ -3332,7 +3336,7 @@ int sqlite3MemCompare(const Mem *pMem1, const Mem *pMem2, const CollSeq *pColl){
    assert( !pColl || pColl->xCmp );

    if( pColl ){
-      return vdbeCompareMemString(pMem1, pMem2, pColl);
+      return vdbeCompareMemString(pMem1, pMem2, pColl, 0);
    }
    /* If a NULL pointer was passed as the collate function, fall through
    ** to the blob case and use memcmp().  */
@@ -3403,10 +3407,15 @@ static i64 vdbeRecordDecodeInt(u32 serial_type, const u8 *aKey){
 ** Key1 and Key2 do not have to contain the same number of fields. If all 
 ** fields that appear in both keys are equal, then pPKey2->default_rc is 
 ** returned.
+**
+** If database corruption is discovered, set pPKey2->errCode to 
+** SQLITE_CORRUPT and return 0. If an OOM error is encountered, 
+** pPKey2->errCode is set to SQLITE_NOMEM and, if it is not NULL, the
+** malloc-failed flag set on database handle (pPKey2->pKeyInfo->db).
 */
 int sqlite3VdbeRecordCompare(
  int nKey1, const void *pKey1,   /* Left key */
-  const UnpackedRecord *pPKey2,   /* Right key */
+  UnpackedRecord *pPKey2,         /* Right key */
  int bSkip                       /* If true, skip the first field */
 ){
  u32 d1;                         /* Offset into aKey[] of next data element */
@@ -3432,6 +3441,10 @@ int sqlite3VdbeRecordCompare(
  }else{
    idx1 = getVarint32(aKey1, szHdr1);
    d1 = szHdr1;
+    if( d1>(unsigned)nKey1 ){ 
+      pPKey2->errCode = (u8)SQLITE_CORRUPT_BKPT;
+      return 0;  /* Corruption */
+    }
    i = 0;
  }

@@ -3508,13 +3521,16 @@ int sqlite3VdbeRecordCompare(
        testcase( (d1+mem1.n)==(unsigned)nKey1 );
        testcase( (d1+mem1.n+1)==(unsigned)nKey1 );
        if( (d1+mem1.n) > (unsigned)nKey1 ){
-          rc = 1;                /* Corruption */
+          pPKey2->errCode = (u8)SQLITE_CORRUPT_BKPT;
+          return 0;                /* Corruption */
        }else if( pKeyInfo->aColl[i] ){
          mem1.enc = pKeyInfo->enc;
          mem1.db = pKeyInfo->db;
          mem1.flags = MEM_Str;
          mem1.z = (char*)&aKey1[d1];
-          rc = vdbeCompareMemString(&mem1, pRhs, pKeyInfo->aColl[i]);
+          rc = vdbeCompareMemString(
+              &mem1, pRhs, pKeyInfo->aColl[i], &pPKey2->errCode
+          );
        }else{
          int nCmp = MIN(mem1.n, pRhs->n);
          rc = memcmp(&aKey1[d1], pRhs->z, nCmp);
@@ -3534,7 +3550,8 @@ int sqlite3VdbeRecordCompare(
        testcase( (d1+nStr)==(unsigned)nKey1 );
        testcase( (d1+nStr+1)==(unsigned)nKey1 );
        if( (d1+nStr) > (unsigned)nKey1 ){
-          rc = 1;                /* Corruption */
+          pPKey2->errCode = (u8)SQLITE_CORRUPT_BKPT;
+          return 0;                /* Corruption */
        }else{
          int nCmp = MIN(nStr, pRhs->n);
          rc = memcmp(&aKey1[d1], pRhs->z, nCmp);
@@ -3553,7 +3570,7 @@ int sqlite3VdbeRecordCompare(
      if( pKeyInfo->aSortOrder[i] ){
        rc = -rc;
      }
-      assert( CORRUPT_DB
+      assert( CORRUPT_DB || pKeyInfo->db==0
          || (rc<0 && vdbeRecordCompareDebug(nKey1, pKey1, pPKey2)<0)
          || (rc>0 && vdbeRecordCompareDebug(nKey1, pKey1, pPKey2)>0)
          || pKeyInfo->db->mallocFailed
@@ -3587,10 +3604,13 @@ int sqlite3VdbeRecordCompare(
 ** that (a) the first field of pPKey2 is an integer, and (b) the 
 ** size-of-header varint at the start of (pKey1/nKey1) fits in a single
 ** byte (i.e. is less than 128).
+**
+** To avoid concerns about buffer overreads, this routine is only used
+** on schemas where the maximum valid header size is 63 bytes or less.
 */
 static int vdbeRecordCompareInt(
  int nKey1, const void *pKey1, /* Left key */
-  const UnpackedRecord *pPKey2, /* Right key */
+  UnpackedRecord *pPKey2,       /* Right key */
  int bSkip                     /* Ignored */
 ){
  const u8 *aKey = &((const u8*)pKey1)[*(const u8*)pKey1 & 0x3F];
@@ -3603,6 +3623,7 @@ static int vdbeRecordCompareInt(
  UNUSED_PARAMETER(bSkip);

  assert( bSkip==0 );
+  assert( (*(u8*)pKey1)<=0x3F || CORRUPT_DB );
  switch( serial_type ){
    case 1: { /* 1-byte signed integer */
      lhs = ONE_BYTE_INT(aKey);
@@ -3687,7 +3708,7 @@ static int vdbeRecordCompareInt(
 */
 static int vdbeRecordCompareString(
  int nKey1, const void *pKey1, /* Left key */
-  const UnpackedRecord *pPKey2, /* Right key */
+  UnpackedRecord *pPKey2,       /* Right key */
  int bSkip
 ){
  const u8 *aKey1 = (const u8*)pKey1;
@@ -3708,7 +3729,10 @@ static int vdbeRecordCompareString(
    int szHdr = aKey1[0];

    nStr = (serial_type-12) / 2;
-    if( (szHdr + nStr) > nKey1 ) return 0;    /* Corruption */
+    if( (szHdr + nStr) > nKey1 ){
+      pPKey2->errCode = (u8)SQLITE_CORRUPT_BKPT;
+      return 0;    /* Corruption */
+    }
    nCmp = MIN( pPKey2->aMem[0].n, nStr );
    res = memcmp(&aKey1[szHdr], pPKey2->aMem[0].z, nCmp);

@@ -3873,7 +3897,7 @@ idx_rowid_corruption:
 */
 int sqlite3VdbeIdxKeyCompare(
  VdbeCursor *pC,                  /* The cursor to compare against */
-  const UnpackedRecord *pUnpacked, /* Unpacked version of key */
+  UnpackedRecord *pUnpacked,       /* Unpacked version of key */
  int *res                         /* Write the comparison result here */
 ){
  i64 nCellKey = 0;
@@ -133,7 +133,7 @@ int sqlite3_blob_open(
  ** which closes the b-tree cursor and (possibly) commits the 
  ** transaction.
  */
-  static const int iLn = __LINE__+4;
+  static const int iLn = VDBE_OFFSET_LINENO(4);
  static const VdbeOpList openBlob[] = {
    /* {OP_Transaction, 0, 0, 0},  // 0: Inserted separately */
    {OP_TableLock, 0, 0, 0},       /* 1: Acquire a read or write lock */
@@ -39,7 +39,7 @@ int sqlite3WhereIsDistinct(WhereInfo *pWInfo){
 ** Return FALSE if the output needs to be sorted.
 */
 int sqlite3WhereIsOrdered(WhereInfo *pWInfo){
-  return pWInfo->bOBSat!=0;
+  return pWInfo->nOBSat;
 }

 /*
@@ -47,6 +47,7 @@ int sqlite3WhereIsOrdered(WhereInfo *pWInfo){
 ** immediately with the next row of a WHERE clause.
 */
 int sqlite3WhereContinueLabel(WhereInfo *pWInfo){
+  assert( pWInfo->iContinue!=0 );
  return pWInfo->iContinue;
 }

@@ -3036,8 +3037,11 @@ static Bitmask codeOneLoopStart(
    ** the first one after the nEq equality constraints in the index,
    ** this requires some special handling.
    */
+    assert( pWInfo->pOrderBy==0
+         || pWInfo->pOrderBy->nExpr==1
+         || (pWInfo->wctrlFlags&WHERE_ORDERBY_MIN)==0 );
    if( (pWInfo->wctrlFlags&WHERE_ORDERBY_MIN)!=0
-     && (pWInfo->bOBSat!=0)
+     && pWInfo->nOBSat>0
     && (pIdx->nKeyCol>nEq)
    ){
      assert( pLoop->u.btree.nSkip==0 );
@@ -3208,8 +3212,7 @@ static Bitmask codeOneLoopStart(
      pLevel->op = OP_Next;
    }
    pLevel->p1 = iIdxCur;
-    assert( (WHERE_UNQ_WANTED>>16)==1 );
-    pLevel->p3 = (pLoop->wsFlags>>16)&1;
+    pLevel->p3 = (pLoop->wsFlags&WHERE_UNQ_WANTED)!=0 ? 1:0;
    if( (pLoop->wsFlags & WHERE_CONSTRAINT)==0 ){
      pLevel->p5 = SQLITE_STMTSTATUS_FULLSCAN_STEP;
    }else{
@@ -3708,6 +3711,124 @@ static void whereInfoFree(sqlite3 *db, WhereInfo *pWInfo){
  }
 }

+/*
+** Return TRUE if the set of WHERE clause terms used by pA is a proper
+** subset of the WHERE clause terms used by pB.
+*/
+static int whereLoopProperSubset(const WhereLoop *pA, const WhereLoop *pB){
+  int i, j;
+  assert( pA->nLTerm<pB->nLTerm );  /* Checked by calling function */
+  for(j=0, i=pA->nLTerm-1; i>=0 && j>=0; i--){
+    for(j=pB->nLTerm-1; j>=0; j--){
+      if( pB->aLTerm[j]==pA->aLTerm[i] ) break;
+    }
+  }
+  return j>=0;
+}
+
+/*
+** Try to adjust the cost of WhereLoop pTemplate upwards or downwards so
+** that:
+**
+**   (1) pTemplate costs less than any other WhereLoops that are a proper
+**       subset of pTemplate
+**
+**   (2) pTemplate costs more than any other WhereLoops for which pTemplate
+**       is a proper subset.
+**
+** To say "WhereLoop X is a proper subset of Y" means that X uses fewer
+** WHERE clause terms than Y and that every WHERE clause term used by X is
+** also used by Y.
+*/
+static void whereLoopAdjustCost(const WhereLoop *p, WhereLoop *pTemplate){
+  if( (pTemplate->wsFlags & WHERE_INDEXED)==0 ) return;
+  for(; p; p=p->pNextLoop){
+    if( p->iTab!=pTemplate->iTab ) continue;
+    if( (p->wsFlags & WHERE_INDEXED)==0 ) continue;
+    if( p->nLTerm<pTemplate->nLTerm
+     && (p->rRun<pTemplate->rRun || (p->rRun==pTemplate->rRun &&
+                                     p->nOut<=pTemplate->nOut))
+     && whereLoopProperSubset(p, pTemplate)
+    ){
+      pTemplate->rRun = p->rRun;
+      pTemplate->nOut = p->nOut - 1;
+    }else
+    if( p->nLTerm>pTemplate->nLTerm
+     && (p->rRun>pTemplate->rRun || (p->rRun==pTemplate->rRun &&
+                                     p->nOut>=pTemplate->nOut))
+     && whereLoopProperSubset(pTemplate, p)
+    ){
+      pTemplate->rRun = p->rRun;
+      pTemplate->nOut = p->nOut + 1;
+    }
+  }
+}
+
+/*
+** Search the list of WhereLoops in *ppPrev looking for one that can be
+** supplanted by pTemplate.
+**
+** Return NULL if the WhereLoop list contains an entry that can supplant
+** pTemplate, in other words if pTemplate does not belong on the list.
+**
+** If pX is a WhereLoop that pTemplate can supplant, then return the
+** link that points to pX.
+**
+** If pTemplate cannot supplant any existing element of the list but needs
+** to be added to the list, then return a pointer to the tail of the list.
+*/
+static WhereLoop **whereLoopFindLesser(
+  WhereLoop **ppPrev,
+  const WhereLoop *pTemplate
+){
+  WhereLoop *p;
+  for(p=(*ppPrev); p; ppPrev=&p->pNextLoop, p=*ppPrev){
+    if( p->iTab!=pTemplate->iTab || p->iSortIdx!=pTemplate->iSortIdx ){
+      /* If either the iTab or iSortIdx values for two WhereLoop are different
+      ** then those WhereLoops need to be considered separately.  Neither is
+      ** a candidate to replace the other. */
+      continue;
+    }
+    /* In the current implementation, the rSetup value is either zero
+    ** or the cost of building an automatic index (NlogN) and the NlogN
+    ** is the same for compatible WhereLoops. */
+    assert( p->rSetup==0 || pTemplate->rSetup==0 
+                 || p->rSetup==pTemplate->rSetup );
+
+    /* whereLoopAddBtree() always generates and inserts the automatic index
+    ** case first.  Hence compatible candidate WhereLoops never have a larger
+    ** rSetup. Call this SETUP-INVARIANT */
+    assert( p->rSetup>=pTemplate->rSetup );
+
+    /* If existing WhereLoop p is better than pTemplate, pTemplate can be
+    ** discarded.  WhereLoop p is better if:
+    **   (1)  p has no more dependencies than pTemplate, and
+    **   (2)  p has an equal or lower cost than pTemplate
+    */
+    if( (p->prereq & pTemplate->prereq)==p->prereq    /* (1)  */
+     && p->rSetup<=pTemplate->rSetup                  /* (2a) */
+     && p->rRun<=pTemplate->rRun                      /* (2b) */
+     && p->nOut<=pTemplate->nOut                      /* (2c) */
+    ){
+      return 0;  /* Discard pTemplate */
+    }
+
+    /* If pTemplate is always better than p, then cause p to be overwritten
+    ** with pTemplate.  pTemplate is better than p if:
+    **   (1)  pTemplate has no more dependences than p, and
+    **   (2)  pTemplate has an equal or lower cost than p.
+    */
+    if( (p->prereq & pTemplate->prereq)==pTemplate->prereq   /* (1)  */
+     && p->rRun>=pTemplate->rRun                             /* (2a) */
+     && p->nOut>=pTemplate->nOut                             /* (2b) */
+    ){
+      assert( p->rSetup>=pTemplate->rSetup ); /* SETUP-INVARIANT above */
+      break;   /* Cause p to be overwritten by pTemplate */
+    }
+  }
+  return ppPrev;
+}
+
 /*
 ** Insert or replace a WhereLoop entry using the template supplied.
 **
@@ -3717,25 +3838,23 @@ static void whereInfoFree(sqlite3 *db, WhereInfo *pWInfo){
 ** fewer dependencies than the template.  Otherwise a new WhereLoop is
 ** added based on the template.
 **
-** If pBuilder->pOrSet is not NULL then we only care about only the
+** If pBuilder->pOrSet is not NULL then we care about only the
 ** prerequisites and rRun and nOut costs of the N best loops.  That
 ** information is gathered in the pBuilder->pOrSet object.  This special
 ** processing mode is used only for OR clause processing.
 **
 ** When accumulating multiple loops (when pBuilder->pOrSet is NULL) we
 ** still might overwrite similar loops with the new template if the
-** template is better.  Loops may be overwritten if the following 
+** new template is better.  Loops may be overwritten if the following 
 ** conditions are met:
 **
 **    (1)  They have the same iTab.
 **    (2)  They have the same iSortIdx.
 **    (3)  The template has same or fewer dependencies than the current loop
 **    (4)  The template has the same or lower cost than the current loop
-**    (5)  The template uses more terms of the same index but has no additional
-**         dependencies          
 */
 static int whereLoopInsert(WhereLoopBuilder *pBuilder, WhereLoop *pTemplate){
-  WhereLoop **ppPrev, *p, *pNext = 0;
+  WhereLoop **ppPrev, *p;
  WhereInfo *pWInfo = pBuilder->pWInfo;
  sqlite3 *db = pWInfo->pParse->db;

@@ -3758,64 +3877,23 @@ static int whereLoopInsert(WhereLoopBuilder *pBuilder, WhereLoop *pTemplate){
    return SQLITE_OK;
  }

-  /* Search for an existing WhereLoop to overwrite, or which takes
-  ** priority over pTemplate.
+  /* Look for an existing WhereLoop to replace with pTemplate
  */
-  for(ppPrev=&pWInfo->pLoops, p=*ppPrev; p; ppPrev=&p->pNextLoop, p=*ppPrev){
-    if( p->iTab!=pTemplate->iTab || p->iSortIdx!=pTemplate->iSortIdx ){
-      /* If either the iTab or iSortIdx values for two WhereLoop are different
-      ** then those WhereLoops need to be considered separately.  Neither is
-      ** a candidate to replace the other. */
-      continue;
-    }
-    /* In the current implementation, the rSetup value is either zero
-    ** or the cost of building an automatic index (NlogN) and the NlogN
-    ** is the same for compatible WhereLoops. */
-    assert( p->rSetup==0 || pTemplate->rSetup==0 
-                 || p->rSetup==pTemplate->rSetup );
+  whereLoopAdjustCost(pWInfo->pLoops, pTemplate);
+  ppPrev = whereLoopFindLesser(&pWInfo->pLoops, pTemplate);

-    /* whereLoopAddBtree() always generates and inserts the automatic index
-    ** case first.  Hence compatible candidate WhereLoops never have a larger
-    ** rSetup. Call this SETUP-INVARIANT */
-    assert( p->rSetup>=pTemplate->rSetup );
-
-    if( (p->prereq & pTemplate->prereq)==p->prereq
-     && p->rSetup<=pTemplate->rSetup
-     && p->rRun<=pTemplate->rRun
-     && p->nOut<=pTemplate->nOut
-    ){
-      /* This branch taken when p is equal or better than pTemplate in 
-      ** all of (1) dependencies (2) setup-cost, (3) run-cost, and
-      ** (4) number of output rows. */
-      assert( p->rSetup==pTemplate->rSetup );
-      if( p->prereq==pTemplate->prereq
-       && p->nLTerm<pTemplate->nLTerm
-       && (p->wsFlags & pTemplate->wsFlags & WHERE_INDEXED)!=0
-       && (p->u.btree.pIndex==pTemplate->u.btree.pIndex
-          || pTemplate->rRun+p->nLTerm<=p->rRun+pTemplate->nLTerm)
-      ){
-        /* Overwrite an existing WhereLoop with an similar one that uses
-        ** more terms of the index */
-        pNext = p->pNextLoop;
-        break;
-      }else{
-        /* pTemplate is not helpful.
-        ** Return without changing or adding anything */
-        goto whereLoopInsert_noop;
-      }
-    }
-    if( (p->prereq & pTemplate->prereq)==pTemplate->prereq
-     && p->rRun>=pTemplate->rRun
-     && p->nOut>=pTemplate->nOut
-    ){
-      /* Overwrite an existing WhereLoop with a better one: one that is
-      ** better at one of (1) dependencies, (2) setup-cost, (3) run-cost
-      ** or (4) number of output rows, and is no worse in any of those
-      ** categories. */
-      assert( p->rSetup>=pTemplate->rSetup ); /* SETUP-INVARIANT above */
-      pNext = p->pNextLoop;
-      break;
+  if( ppPrev==0 ){
+    /* There already exists a WhereLoop on the list that is better
+    ** than pTemplate, so just ignore pTemplate */
+#if WHERETRACE_ENABLED /* 0x8 */
+    if( sqlite3WhereTrace & 0x8 ){
+      sqlite3DebugPrintf("ins-noop: ");
+      whereLoopPrint(pTemplate, pBuilder->pWC);
    }
+#endif
+    return SQLITE_OK;  
+  }else{
+    p = *ppPrev;
  }

  /* If we reach this point it means that either p[] should be overwritten
@@ -3833,13 +3911,33 @@ static int whereLoopInsert(WhereLoopBuilder *pBuilder, WhereLoop *pTemplate){
  }
 #endif
  if( p==0 ){
-    p = sqlite3DbMallocRaw(db, sizeof(WhereLoop));
+    /* Allocate a new WhereLoop to add to the end of the list */
+    *ppPrev = p = sqlite3DbMallocRaw(db, sizeof(WhereLoop));
    if( p==0 ) return SQLITE_NOMEM;
    whereLoopInit(p);
+    p->pNextLoop = 0;
+  }else{
+    /* We will be overwriting WhereLoop p[].  But before we do, first
+    ** go through the rest of the list and delete any other entries besides
+    ** p[] that are also supplated by pTemplate */
+    WhereLoop **ppTail = &p->pNextLoop;
+    WhereLoop *pToDel;
+    while( *ppTail ){
+      ppTail = whereLoopFindLesser(ppTail, pTemplate);
+      if( NEVER(ppTail==0) ) break;
+      pToDel = *ppTail;
+      if( pToDel==0 ) break;
+      *ppTail = pToDel->pNextLoop;
+#if WHERETRACE_ENABLED /* 0x8 */
+      if( sqlite3WhereTrace & 0x8 ){
+        sqlite3DebugPrintf("ins-del: ");
+        whereLoopPrint(pToDel, pBuilder->pWC);
+      }
+#endif
+      whereLoopDelete(db, pToDel);
+    }
  }
  whereLoopXfer(db, p, pTemplate);
-  p->pNextLoop = pNext;
-  *ppPrev = p;
  if( (p->wsFlags & WHERE_VIRTUALTABLE)==0 ){
    Index *pIndex = p->u.btree.pIndex;
    if( pIndex && pIndex->tnum==0 ){
@@ -3847,16 +3945,6 @@ static int whereLoopInsert(WhereLoopBuilder *pBuilder, WhereLoop *pTemplate){
    }
  }
  return SQLITE_OK;
-
-  /* Jump here if the insert is a no-op */
-whereLoopInsert_noop:
-#if WHERETRACE_ENABLED /* 0x8 */
-  if( sqlite3WhereTrace & 0x8 ){
-    sqlite3DebugPrintf("ins-noop: ");
-    whereLoopPrint(pTemplate, pBuilder->pWC);
-  }
-#endif
-  return SQLITE_OK;  
 }

 /*
@@ -3974,7 +4062,10 @@ static int whereLoopAddBtreeIndex(
    pNew->aLTerm[pNew->nLTerm++] = 0;
    pNew->wsFlags |= WHERE_SKIPSCAN;
    nIter = sqlite3LogEst(pProbe->aiRowEst[0]/pProbe->aiRowEst[saved_nEq+1]);
+    pNew->rRun = rLogSize + nIter;
+    pNew->nOut += nIter;
    whereLoopAddBtreeIndex(pBuilder, pSrc, pProbe, nIter);
+    pNew->nOut = saved_nOut;
  }
  for(; rc==SQLITE_OK && pTerm!=0; pTerm = whereScanNext(&scan)){
    int nIn = 0;
@@ -4007,6 +4098,8 @@ static int whereLoopAddBtreeIndex(
        /* "x IN (value, value, ...)" */
        nIn = sqlite3LogEst(pExpr->x.pList->nExpr);
      }
+      assert( nIn>0 );  /* RHS always has 2 or more terms...  The parser
+                        ** changes "x IN (?)" into "x=?". */
      pNew->rRun += nIn;
      pNew->u.btree.nEq++;
      pNew->nOut = nRowEst + nInMul + nIn;
@@ -4320,18 +4413,34 @@ static int whereLoopAddBtree(
          )
      ){
        pNew->iSortIdx = b ? iSortIdx : 0;
+        /* TUNING:  The base cost of an index scan is N + log2(N).
+        ** The log2(N) is for the initial seek to the beginning and the N
+        ** is for the scan itself. */
+        pNew->rRun = sqlite3LogEstAdd(rSize, rLogSize);
        if( m==0 ){
          /* TUNING: Cost of a covering index scan is K*(N + log2(N)).
          **  +  The extra factor K of between 1.1 and 3.0 that depends
          **     on the relative sizes of the table and the index.  K
          **     is smaller for smaller indices, thus favoring them.
+          **     The upper bound on K (3.0) matches the penalty factor
+          **     on a full table scan that tries to encourage the use of
+          **     indexed lookups over full scans.
          */
-          pNew->rRun = sqlite3LogEstAdd(rSize,rLogSize) + 1 +
-                        (15*pProbe->szIdxRow)/pTab->szTabRow;
+          pNew->rRun +=  1 + (15*pProbe->szIdxRow)/pTab->szTabRow;
        }else{
-          /* TUNING: Cost of scanning a non-covering index is (N+1)*log2(N)
-          ** which we will simplify to just N*log2(N) */
-          pNew->rRun = rSize + rLogSize;
+          /* TUNING: The cost of scanning a non-covering index is multiplied
+          ** by log2(N) to account for the binary search of the main table
+          ** that must happen for each row of the index.
+          ** TODO: Should there be a multiplier here, analogous to the 3x
+          ** multiplier for a fulltable scan or covering index scan, to
+          ** further discourage the use of an index scan?  Or is the log2(N)
+          ** term sufficient discouragement?
+          ** TODO: What if some or all of the WHERE clause terms can be
+          ** computed without reference to the original table.  Then the
+          ** penality should reduce to logK where K is the number of output
+          ** rows.
+          */
+          pNew->rRun += rLogSize;
        }
        whereLoopOutputAdjust(pWC, pNew);
        rc = whereLoopInsert(pBuilder, pNew);
@@ -4503,8 +4612,8 @@ static int whereLoopAddVirtual(
      pNew->u.vtab.needFree = pIdxInfo->needToFreeIdxStr;
      pIdxInfo->needToFreeIdxStr = 0;
      pNew->u.vtab.idxStr = pIdxInfo->idxStr;
-      pNew->u.vtab.isOrdered = (u8)((pIdxInfo->nOrderBy!=0)
-                                     && pIdxInfo->orderByConsumed);
+      pNew->u.vtab.isOrdered = (i8)(pIdxInfo->orderByConsumed ?
+                                      pIdxInfo->nOrderBy : 0);
      pNew->rSetup = 0;
      pNew->rRun = sqlite3LogEstFromDouble(pIdxInfo->estimatedCost);
      pNew->nOut = sqlite3LogEst(pIdxInfo->estimatedRows);
@@ -4665,11 +4774,11 @@ static int whereLoopAddAll(WhereLoopBuilder *pBuilder){
 /*
 ** Examine a WherePath (with the addition of the extra WhereLoop of the 5th
 ** parameters) to see if it outputs rows in the requested ORDER BY
-** (or GROUP BY) without requiring a separate sort operation.  Return:
+** (or GROUP BY) without requiring a separate sort operation.  Return N:
 ** 
-**    0:  ORDER BY is not satisfied.  Sorting required
-**    1:  ORDER BY is satisfied.      Omit sorting
-**   -1:  Unknown at this time
+**   N>0:   N terms of the ORDER BY clause are satisfied
+**   N==0:  No terms of the ORDER BY clause are satisfied
+**   N<0:   Unknown yet how many terms of ORDER BY might be satisfied.   
 **
 ** Note that processing for WHERE_GROUPBY and WHERE_DISTINCTBY is not as
 ** strict.  With GROUP BY and DISTINCT the only requirement is that
@@ -4679,7 +4788,7 @@ static int whereLoopAddAll(WhereLoopBuilder *pBuilder){
 ** the pOrderBy terms can be matched in any order.  With ORDER BY, the 
 ** pOrderBy terms must be matched in strict left-to-right order.
 */
-static int wherePathSatisfiesOrderBy(
+static i8 wherePathSatisfiesOrderBy(
  WhereInfo *pWInfo,    /* The WHERE clause */
  ExprList *pOrderBy,   /* ORDER BY or GROUP BY or DISTINCT clause to check */
  WherePath *pPath,     /* The WherePath to check */
@@ -4864,23 +4973,23 @@ static int wherePathSatisfiesOrderBy(
          isMatch = 1;
          break;
        }
+        if( isMatch && (pWInfo->wctrlFlags & WHERE_GROUPBY)==0 ){
+          /* Make sure the sort order is compatible in an ORDER BY clause.
+          ** Sort order is irrelevant for a GROUP BY clause. */
+          if( revSet ){
+            if( (rev ^ revIdx)!=pOrderBy->a[i].sortOrder ) isMatch = 0;
+          }else{
+            rev = revIdx ^ pOrderBy->a[i].sortOrder;
+            if( rev ) *pRevMask |= MASKBIT(iLoop);
+            revSet = 1;
+          }
+        }
        if( isMatch ){
          if( iColumn<0 ){
            testcase( distinctColumns==0 );
            distinctColumns = 1;
          }
          obSat |= MASKBIT(i);
-          if( (pWInfo->wctrlFlags & WHERE_GROUPBY)==0 ){
-            /* Make sure the sort order is compatible in an ORDER BY clause.
-            ** Sort order is irrelevant for a GROUP BY clause. */
-            if( revSet ){
-              if( (rev ^ revIdx)!=pOrderBy->a[i].sortOrder ) return 0;
-            }else{
-              rev = revIdx ^ pOrderBy->a[i].sortOrder;
-              if( rev ) *pRevMask |= MASKBIT(iLoop);
-              revSet = 1;
-            }
-          }
        }else{
          /* No match found */
          if( j==0 || j<nKeyCol ){
@@ -4912,8 +5021,14 @@ static int wherePathSatisfiesOrderBy(
      }
    }
  } /* End the loop over all WhereLoops from outer-most down to inner-most */
-  if( obSat==obDone ) return 1;
-  if( !isOrderDistinct ) return 0;
+  if( obSat==obDone ) return (i8)nOrderBy;
+  if( !isOrderDistinct ){
+    for(i=nOrderBy-1; i>0; i--){
+      Bitmask m = MASKBIT(i) - 1;
+      if( (obSat&m)==m ) return i;
+    }
+    return 0;
+  }
  return -1;
 }

@@ -4950,11 +5065,11 @@ static int wherePathSolver(WhereInfo *pWInfo, LogEst nRowEst){
  int iLoop;                /* Loop counter over the terms of the join */
  int ii, jj;               /* Loop counters */
  int mxI = 0;              /* Index of next entry to replace */
+  int nOrderBy;             /* Number of ORDER BY clause terms */
  LogEst rCost;             /* Cost of a path */
  LogEst nOut;              /* Number of outputs */
  LogEst mxCost = 0;        /* Maximum cost of a set of paths */
  LogEst mxOut = 0;         /* Maximum nOut value on the set of paths */
-  LogEst rSortCost;         /* Cost to do a sort */
  int nTo, nFrom;           /* Number of valid entries in aTo[] and aFrom[] */
  WherePath *aFrom;         /* All nFrom paths at the previous level */
  WherePath *aTo;           /* The nTo best paths at the current level */
@@ -4996,16 +5111,12 @@ static int wherePathSolver(WhereInfo *pWInfo, LogEst nRowEst){

  /* Precompute the cost of sorting the final result set, if the caller
  ** to sqlite3WhereBegin() was concerned about sorting */
-  rSortCost = 0;
  if( pWInfo->pOrderBy==0 || nRowEst==0 ){
-    aFrom[0].isOrderedValid = 1;
+    aFrom[0].isOrdered = 0;
+    nOrderBy = 0;
  }else{
-    /* TUNING: Estimated cost of sorting is 48*N*log2(N) where N is the
-    ** number of output rows. The 48 is the expected size of a row to sort. 
-    ** FIXME:  compute a better estimate of the 48 multiplier based on the
-    ** result set expressions. */
-    rSortCost = nRowEst + estLog(nRowEst);
-    WHERETRACE(0x002,("---- sort cost=%-3d\n", rSortCost));
+    aFrom[0].isOrdered = -1;
+    nOrderBy = pWInfo->pOrderBy->nExpr;
  }

  /* Compute successively longer WherePaths using the previous generation
@@ -5017,8 +5128,7 @@ static int wherePathSolver(WhereInfo *pWInfo, LogEst nRowEst){
      for(pWLoop=pWInfo->pLoops; pWLoop; pWLoop=pWLoop->pNextLoop){
        Bitmask maskNew;
        Bitmask revMask = 0;
-        u8 isOrderedValid = pFrom->isOrderedValid;
-        u8 isOrdered = pFrom->isOrdered;
+        i8 isOrdered = pFrom->isOrdered;
        if( (pWLoop->prereq & ~pFrom->maskLoop)!=0 ) continue;
        if( (pWLoop->maskSelf & pFrom->maskLoop)!=0 ) continue;
        /* At this point, pWLoop is a candidate to be the next loop. 
@@ -5027,21 +5137,35 @@ static int wherePathSolver(WhereInfo *pWInfo, LogEst nRowEst){
        rCost = sqlite3LogEstAdd(rCost, pFrom->rCost);
        nOut = pFrom->nRow + pWLoop->nOut;
        maskNew = pFrom->maskLoop | pWLoop->maskSelf;
-        if( !isOrderedValid ){
-          switch( wherePathSatisfiesOrderBy(pWInfo,
+        if( isOrdered<0 ){
+          isOrdered = wherePathSatisfiesOrderBy(pWInfo,
                       pWInfo->pOrderBy, pFrom, pWInfo->wctrlFlags,
-                       iLoop, pWLoop, &revMask) ){
-            case 1:  /* Yes.  pFrom+pWLoop does satisfy the ORDER BY clause */
-              isOrdered = 1;
-              isOrderedValid = 1;
-              break;
-            case 0:  /* No.  pFrom+pWLoop will require a separate sort */
-              isOrdered = 0;
-              isOrderedValid = 1;
-              rCost = sqlite3LogEstAdd(rCost, rSortCost);
-              break;
-            default: /* Cannot tell yet.  Try again on the next iteration */
-              break;
+                       iLoop, pWLoop, &revMask);
+          if( isOrdered>=0 && isOrdered<nOrderBy ){
+            /* TUNING: Estimated cost of sorting is N*log(N).
+            ** If the order-by clause has X terms but only the last Y terms
+            ** are out of order, then block-sorting will reduce the sorting
+            ** cost to N*log(N)*log(Y/X).  The log(Y/X) term is computed
+            ** by rScale.
+            ** TODO: Should the sorting cost get a small multiplier to help
+            ** discourage the use of sorting and encourage the use of index
+            ** scans instead?
+            */
+            LogEst rScale, rSortCost;
+            assert( nOrderBy>0 );
+            rScale = sqlite3LogEst((nOrderBy-isOrdered)*100/nOrderBy) - 66;
+            rSortCost = nRowEst + estLog(nRowEst) + rScale;
+            /* TUNING: The cost of implementing DISTINCT using a B-TREE is
+            ** also N*log(N) but it has a larger constant of proportionality.
+            ** Multiply by 3.0. */
+            if( pWInfo->wctrlFlags & WHERE_WANT_DISTINCT ){
+              rSortCost += 16;
+            }
+            WHERETRACE(0x002,
+               ("---- sort cost=%-3d (%d/%d) increases cost %3d to %-3d\n",
+                rSortCost, (nOrderBy-isOrdered), nOrderBy, rCost,
+                sqlite3LogEstAdd(rCost,rSortCost)));
+            rCost = sqlite3LogEstAdd(rCost, rSortCost);
          }
        }else{
          revMask = pFrom->revLoop;
@@ -5049,7 +5173,7 @@ static int wherePathSolver(WhereInfo *pWInfo, LogEst nRowEst){
        /* Check to see if pWLoop should be added to the mxChoice best so far */
        for(jj=0, pTo=aTo; jj<nTo; jj++, pTo++){
          if( pTo->maskLoop==maskNew
-           && pTo->isOrderedValid==isOrderedValid
+           && ((pTo->isOrdered^isOrdered)&80)==0
           && ((pTo->rCost<=rCost && pTo->nRow<=nOut) ||
                (pTo->rCost>=rCost && pTo->nRow>=nOut))
          ){
@@ -5063,7 +5187,7 @@ static int wherePathSolver(WhereInfo *pWInfo, LogEst nRowEst){
            if( sqlite3WhereTrace&0x4 ){
              sqlite3DebugPrintf("Skip   %s cost=%-3d,%3d order=%c\n",
                  wherePathName(pFrom, iLoop, pWLoop), rCost, nOut,
-                  isOrderedValid ? (isOrdered ? 'Y' : 'N') : '?');
+                  isOrdered>=0 ? isOrdered+'0' : '?');
            }
 #endif
            continue;
@@ -5081,7 +5205,7 @@ static int wherePathSolver(WhereInfo *pWInfo, LogEst nRowEst){
          if( sqlite3WhereTrace&0x4 ){
            sqlite3DebugPrintf("New    %s cost=%-3d,%3d order=%c\n",
                wherePathName(pFrom, iLoop, pWLoop), rCost, nOut,
-                isOrderedValid ? (isOrdered ? 'Y' : 'N') : '?');
+                isOrdered>=0 ? isOrdered+'0' : '?');
          }
 #endif
        }else{
@@ -5091,10 +5215,10 @@ static int wherePathSolver(WhereInfo *pWInfo, LogEst nRowEst){
              sqlite3DebugPrintf(
                  "Skip   %s cost=%-3d,%3d order=%c",
                  wherePathName(pFrom, iLoop, pWLoop), rCost, nOut,
-                  isOrderedValid ? (isOrdered ? 'Y' : 'N') : '?');
+                  isOrdered>=0 ? isOrdered+'0' : '?');
              sqlite3DebugPrintf("   vs %s cost=%-3d,%d order=%c\n",
                  wherePathName(pTo, iLoop+1, 0), pTo->rCost, pTo->nRow,
-                  pTo->isOrderedValid ? (pTo->isOrdered ? 'Y' : 'N') : '?');
+                  pTo->isOrdered>=0 ? pTo->isOrdered+'0' : '?');
            }
 #endif
            testcase( pTo->rCost==rCost );
@@ -5107,10 +5231,10 @@ static int wherePathSolver(WhereInfo *pWInfo, LogEst nRowEst){
            sqlite3DebugPrintf(
                "Update %s cost=%-3d,%3d order=%c",
                wherePathName(pFrom, iLoop, pWLoop), rCost, nOut,
-                isOrderedValid ? (isOrdered ? 'Y' : 'N') : '?');
+                isOrdered>=0 ? isOrdered+'0' : '?');
            sqlite3DebugPrintf("  was %s cost=%-3d,%3d order=%c\n",
                wherePathName(pTo, iLoop+1, 0), pTo->rCost, pTo->nRow,
-                pTo->isOrderedValid ? (pTo->isOrdered ? 'Y' : 'N') : '?');
+                pTo->isOrdered>=0 ? pTo->isOrdered+'0' : '?');
          }
 #endif
        }
@@ -5119,7 +5243,6 @@ static int wherePathSolver(WhereInfo *pWInfo, LogEst nRowEst){
        pTo->revLoop = revMask;
        pTo->nRow = nOut;
        pTo->rCost = rCost;
-        pTo->isOrderedValid = isOrderedValid;
        pTo->isOrdered = isOrdered;
        memcpy(pTo->aLoop, pFrom->aLoop, sizeof(WhereLoop*)*iLoop);
        pTo->aLoop[iLoop] = pWLoop;
@@ -5144,8 +5267,8 @@ static int wherePathSolver(WhereInfo *pWInfo, LogEst nRowEst){
      for(ii=0, pTo=aTo; ii<nTo; ii++, pTo++){
        sqlite3DebugPrintf(" %s cost=%-3d nrow=%-3d order=%c",
           wherePathName(pTo, iLoop+1, 0), pTo->rCost, pTo->nRow,
-           pTo->isOrderedValid ? (pTo->isOrdered ? 'Y' : 'N') : '?');
-        if( pTo->isOrderedValid && pTo->isOrdered ){
+           pTo->isOrdered>=0 ? (pTo->isOrdered+'0') : '?');
+        if( pTo->isOrdered>0 ){
          sqlite3DebugPrintf(" rev=0x%llx\n", pTo->revLoop);
        }else{
          sqlite3DebugPrintf("\n");
@@ -5188,13 +5311,18 @@ static int wherePathSolver(WhereInfo *pWInfo, LogEst nRowEst){
    Bitmask notUsed;
    int rc = wherePathSatisfiesOrderBy(pWInfo, pWInfo->pResultSet, pFrom,
                 WHERE_DISTINCTBY, nLoop-1, pFrom->aLoop[nLoop-1], &notUsed);
-    if( rc==1 ) pWInfo->eDistinct = WHERE_DISTINCT_ORDERED;
-  }
-  if( pFrom->isOrdered ){
-    if( pWInfo->wctrlFlags & WHERE_DISTINCTBY ){
+    if( rc==pWInfo->pResultSet->nExpr ){
      pWInfo->eDistinct = WHERE_DISTINCT_ORDERED;
+    }
+  }
+  if( pWInfo->pOrderBy ){
+    if( pWInfo->wctrlFlags & WHERE_DISTINCTBY ){
+      if( pFrom->isOrdered==pWInfo->pOrderBy->nExpr ){
+        pWInfo->eDistinct = WHERE_DISTINCT_ORDERED;
+      }
    }else{
-      pWInfo->bOBSat = 1;
+      pWInfo->nOBSat = pFrom->isOrdered;
+      if( pWInfo->nOBSat<0 ) pWInfo->nOBSat = 0;
      pWInfo->revMask = pFrom->revLoop;
    }
  }
@@ -5279,7 +5407,7 @@ static int whereShortCut(WhereLoopBuilder *pBuilder){
    pLoop->maskSelf = getMask(&pWInfo->sMaskSet, iCur);
    pWInfo->a[0].iTabCur = iCur;
    pWInfo->nRowOut = 1;
-    if( pWInfo->pOrderBy ) pWInfo->bOBSat =  1;
+    if( pWInfo->pOrderBy ) pWInfo->nOBSat =  pWInfo->pOrderBy->nExpr;
    if( pWInfo->wctrlFlags & WHERE_WANT_DISTINCT ){
      pWInfo->eDistinct = WHERE_DISTINCT_UNIQUE;
    }
@@ -5383,7 +5511,7 @@ WhereInfo *sqlite3WhereBegin(
  Parse *pParse,        /* The parser context */
  SrcList *pTabList,    /* FROM clause: A list of all tables to be scanned */
  Expr *pWhere,         /* The WHERE clause */
-  ExprList *pOrderBy,   /* An ORDER BY clause, or NULL */
+  ExprList *pOrderBy,   /* An ORDER BY (or GROUP BY) clause, or NULL */
  ExprList *pResultSet, /* Result set of the query */
  u16 wctrlFlags,       /* One of the WHERE_* flags defined in sqliteInt.h */
  int iIdxCur           /* If WHERE_ONETABLE_ONLY is set, index cursor number */
@@ -5405,6 +5533,10 @@ WhereInfo *sqlite3WhereBegin(
  /* Variable initialization */
  db = pParse->db;
  memset(&sWLB, 0, sizeof(sWLB));
+
+  /* An ORDER/GROUP BY clause of more than 63 terms cannot be optimized */
+  testcase( pOrderBy && pOrderBy->nExpr==BMS-1 );
+  if( pOrderBy && pOrderBy->nExpr>=BMS ) pOrderBy = 0;
  sWLB.pOrderBy = pOrderBy;

  /* Disable the DISTINCT optimization if SQLITE_DistinctOpt is set via
@@ -5449,7 +5581,7 @@ WhereInfo *sqlite3WhereBegin(
  pWInfo->pTabList = pTabList;
  pWInfo->pOrderBy = pOrderBy;
  pWInfo->pResultSet = pResultSet;
-  pWInfo->iBreak = sqlite3VdbeMakeLabel(v);
+  pWInfo->iBreak = pWInfo->iContinue = sqlite3VdbeMakeLabel(v);
  pWInfo->wctrlFlags = wctrlFlags;
  pWInfo->savedNQueryLoop = pParse->nQueryLoop;
  pMaskSet = &pWInfo->sMaskSet;
@@ -5483,7 +5615,7 @@ WhereInfo *sqlite3WhereBegin(
  /* Special case: No FROM clause
  */
  if( nTabList==0 ){
-    if( pOrderBy ) pWInfo->bOBSat = 1;
+    if( pOrderBy ) pWInfo->nOBSat = pOrderBy->nExpr;
    if( wctrlFlags & WHERE_WANT_DISTINCT ){
      pWInfo->eDistinct = WHERE_DISTINCT_UNIQUE;
    }
@@ -5594,8 +5726,8 @@ WhereInfo *sqlite3WhereBegin(
  if( sqlite3WhereTrace ){
    int ii;
    sqlite3DebugPrintf("---- Solution nRow=%d", pWInfo->nRowOut);
-    if( pWInfo->bOBSat ){
-      sqlite3DebugPrintf(" ORDERBY=0x%llx", pWInfo->revMask);
+    if( pWInfo->nOBSat>0 ){
+      sqlite3DebugPrintf(" ORDERBY=%d,0x%llx", pWInfo->nOBSat, pWInfo->revMask);
    }
    switch( pWInfo->eDistinct ){
      case WHERE_DISTINCT_UNIQUE: {
@@ -5877,7 +6009,7 @@ void sqlite3WhereEnd(WhereInfo *pWInfo){
      for(; k<last; k++, pOp++){
        if( pOp->p1!=pLevel->iTabCur ) continue;
        if( pOp->opcode==OP_Column ){
-          pOp->opcode = OP_SCopy;
+          pOp->opcode = OP_Copy;
          pOp->p1 = pOp->p2 + pTabItem->regResult;
          pOp->p2 = pOp->p3;
          pOp->p3 = 0;
@@ -121,7 +121,7 @@ struct WhereLoop {
    struct {               /* Information for virtual tables */
      int idxNum;            /* Index number */
      u8 needFree;           /* True if sqlite3_free(idxStr) is needed */
-      u8 isOrdered;          /* True if satisfies ORDER BY */
+      i8 isOrdered;          /* True if satisfies ORDER BY */
      u16 omitMask;          /* Terms that may be omitted */
      char *idxStr;          /* Index identifier string */
    } vtab;
@@ -183,8 +183,7 @@ struct WherePath {
  Bitmask revLoop;      /* aLoop[]s that should be reversed for ORDER BY */
  LogEst nRow;          /* Estimated number of rows generated by this path */
  LogEst rCost;         /* Total cost of this path */
-  u8 isOrdered;         /* True if this path satisfies ORDER BY */
-  u8 isOrderedValid;    /* True if the isOrdered field is valid */
+  i8 isOrdered;         /* No. of ORDER BY terms satisfied. -1 for unknown */
  WhereLoop **aLoop;    /* Array of WhereLoop objects implementing this path */
 };

@@ -398,7 +397,7 @@ struct WhereInfo {
  Bitmask revMask;          /* Mask of ORDER BY terms that need reversing */
  LogEst nRowOut;           /* Estimated number of output rows */
  u16 wctrlFlags;           /* Flags originally passed to sqlite3WhereBegin() */
-  u8 bOBSat;                /* ORDER BY satisfied by indices */
+  i8 nOBSat;                /* Number of ORDER BY terms satisfied by indices */
  u8 okOnePass;             /* Ok to use one-pass algorithm for UPDATE/DELETE */
  u8 untestedTerms;         /* Not all WHERE terms resolved by outer loop */
  u8 eDistinct;             /* One of the WHERE_DISTINCT_* values below */
@@ -47,12 +47,12 @@ do_test 1.2 {
  catchsql {
    SELECT c FROM t1 WHERE a>'abc';
  }
-} {0 {}}
+} {1 {database disk image is malformed}}
 do_test 1.3 {
  catchsql {
     PRAGMA integrity_check
  }
-} {0 ok}
+} {1 {database disk image is malformed}}
 do_test 1.4 {
  catchsql {
    SELECT c FROM t1 ORDER BY a;
@@ -71,11 +71,6 @@ do_test 2.1 {
  catchsql {
    SELECT rowid FROM t1 WHERE a='abc' and b='xyz123456789XYZ';
  }
-  # The following test result is brittle.  The point above is to try to
-  # force a buffer overread by a corrupt database file.  If we get an
-  # incorrect answer from a corrupt database file, that is OK.  If the
-  # result below changes, that just means that "undefined behavior" has
-  # changed.
-} {/0 .*/}
+} {1 {database disk image is malformed}}

 finish_test
@@ -32,21 +32,48 @@ do_execsql_test 1.1 {
  PRAGMA auto_vacuum=0;
  CREATE TABLE t1(a);
  CREATE INDEX i1 ON t1(a);
-  INSERT INTO t1 VALUES('a');
+  INSERT INTO t1 VALUES('abcdefghijklmnop');
 } {}
 db close

 do_test 1.2 {
  set offset [hexio_get_int [hexio_read test.db [expr 2*1024 + 8] 2]]
  set off [expr 2*1024 + $offset + 1]
-  hexio_write test.db $off FF06
-
-  breakpoint
+  hexio_write test.db $off 7f06
+  sqlite3 db test.db
+  catchsql { SELECT * FROM t1 WHERE a = 10 }
+} {0 {}}

+do_test 1.3 {
+  db close
+  set offset [hexio_get_int [hexio_read test.db [expr 2*1024 + 8] 2]]
+  set off [expr 2*1024 + $offset + 1]
+  hexio_write test.db $off FFFF7f02
  sqlite3 db test.db
  catchsql { SELECT * FROM t1 WHERE a = 10 }
 } {1 {database disk image is malformed}}

+do_test 2.0 {
+  execsql {
+    CREATE TABLE r(x);
+    INSERT INTO r VALUES('ABCDEFGHIJK');
+    CREATE INDEX r1 ON r(x);
+  }
+  set pg [db one {SELECT rootpage FROM sqlite_master WHERE name = 'r1'}]
+} {5}
+
+do_test 2.1 {
+  db close
+  set offset [hexio_get_int [hexio_read test.db [expr (5-1)*1024 + 8] 2]]
+  set off [expr (5-1)*1024 + $offset + 1]
+  hexio_write test.db $off FFFF0004
+  sqlite3 db test.db
+  catchsql { SELECT * FROM r WHERE x >= 10.0 }
+} {1 {database disk image is malformed}}
+
+do_test 2.2 {
+  catchsql { SELECT * FROM r WHERE x >= 10 }
+} {1 {database disk image is malformed}}
+

 finish_test
-
@@ -162,7 +162,7 @@ do_execsql_test 2.0 {
 foreach {tn sql temptables res} {
  1   "a, b FROM t1"                                       {}      {A B a b}
  2   "b, a FROM t1"                                       {}      {B A b a}
-  3   "a, b, c FROM t1"                                    {hash}  {a b c A B C}
+  3   "a, b, c FROM t1"                                    {hash}  {A B C a b c}
  4   "a, b, c FROM t1 ORDER BY a, b, c"                   {btree} {A B C a b c}
  5   "b FROM t1 WHERE a = 'a'"                            {}      {b}
  6   "b FROM t1 ORDER BY +b COLLATE binary"          {btree hash} {B b}
@@ -219,4 +219,32 @@ do_execsql_test 5.2 {
  SELECT count(*) FROM sqlite_master WHERE name LIKE 't8%';
 } {0 6}

+# At one point this was causing a memory leak.
+#
+foreach {tn sql} {
+  1 {}
+  2 { INSERT INTO ft(ft) VALUES('merge=2,2'); }
+} {
+  reset_db
+  do_execsql_test 6.$tn.1 "
+    CREATE TABLE t1(x);
+    CREATE VIRTUAL TABLE ft USING fts3;
+    INSERT INTO ft VALUES('hello world');
+    $sql
+  "
+
+  db close
+  sqlite3 db test.db
+  do_execsql_test 6.$tn.2 { SELECT * FROM t1 } {}
+
+  do_test 6.$tn.3 {
+    sqlite3 db2 test.db
+    db2 eval { DROP TABLE t1 }
+    db2 close
+    set stmt [sqlite3_prepare db { SELECT * FROM ft } -1 dummy]
+    sqlite3_finalize $stmt
+  } {SQLITE_OK}
+  db close
+}
+
 finish_test
@@ -354,6 +354,17 @@ do_test fts3d-6.5 {
    SELECT name FROM sqlite_master WHERE name GLOB '???_*' ORDER BY 1;
  }
 } {xyz_content xyz_segdir xyz_segments}
+
+# ALTER TABLE RENAME on an FTS3 table following an incr-merge op.
+#
+do_test fts3d-6.6 {
+  execsql { INSERT INTO xyz(xyz) VALUES('merge=2,2') }
+  sqlite3 db test.db
+  execsql { 
+    ALTER TABLE xyz RENAME TO ott;
+    SELECT name FROM sqlite_master WHERE name GLOB '???_*' ORDER BY 1;
+  }
+} {ott_content ott_segdir ott_segments ott_stat}
 

 finish_test
@@ -159,4 +159,181 @@ do_test in4-3.12 {
  execsql { SELECT * FROM t3 WHERE x IN (1, 2) AND y IN ()}
 } {}

+# Tests for "... IN (?)" and "... NOT IN (?)".  In other words, tests
+# for when the RHS of IN is a single expression.  This should work the
+# same as the == and <> operators.
+#
+do_execsql_test in4-3.21 {
+  SELECT * FROM t3 WHERE x=10 AND y IN (10);
+} {10 10 10}
+do_execsql_test in4-3.22 {
+  SELECT * FROM t3 WHERE x IN (10) AND y=10;
+} {10 10 10}
+do_execsql_test in4-3.23 {
+  SELECT * FROM t3 WHERE x IN (10) AND y IN (10);
+} {10 10 10}
+do_execsql_test in4-3.24 {
+  SELECT * FROM t3 WHERE x=1 AND y NOT IN (10);
+} {1 1 1}
+do_execsql_test in4-3.25 {
+  SELECT * FROM t3 WHERE x  NOT IN (10) AND y=1;
+} {1 1 1}
+do_execsql_test in4-3.26 {
+  SELECT * FROM t3 WHERE x NOT IN (10) AND y NOT IN (10);
+} {1 1 1}
+
+# The query planner recognizes that "x IN (?)" only generates a
+# single match and can use this information to optimize-out ORDER BY
+# clauses.
+#
+do_execsql_test in4-3.31 {
+  DROP INDEX t3i1;
+  CREATE UNIQUE INDEX t3xy ON t3(x,y);
+
+  SELECT *, '|' FROM t3 A, t3 B
+   WHERE A.x=10 AND A.y IN (10)
+     AND B.x=1 AND B.y IN (1);
+} {10 10 10 1 1 1 |}
+do_execsql_test in4-3.32 {
+  EXPLAIN QUERY PLAN
+  SELECT *, '|' FROM t3 A, t3 B
+   WHERE A.x=10 AND A.y IN (10)
+     AND B.x=1 AND B.y IN (1);
+} {~/B-TREE/}  ;# No separate sorting pass
+do_execsql_test in4-3.33 {
+  SELECT *, '|' FROM t3 A, t3 B
+   WHERE A.x IN (10) AND A.y=10
+     AND B.x IN (1) AND B.y=1;
+} {10 10 10 1 1 1 |}
+do_execsql_test in4-3.34 {
+  EXPLAIN QUERY PLAN
+  SELECT *, '|' FROM t3 A, t3 B
+   WHERE A.x IN (10) AND A.y=10
+     AND B.x IN (1) AND B.y=1;
+} {~/B-TREE/}  ;# No separate sorting pass
+
+# An expression of the form "x IN (?,?)" creates an ephemeral table to
+# hold the list of values on the RHS.  But "x IN (?)" does not create
+# an ephemeral table.
+#
+do_execsql_test in4-3.41 {
+  SELECT * FROM t3 WHERE x IN (10,11);
+} {10 10 10}
+do_execsql_test in4-3.42 {
+  EXPLAIN
+  SELECT * FROM t3 WHERE x IN (10,11);
+} {/OpenEphemeral/}
+do_execsql_test in4-3.43 {
+  SELECT * FROM t3 WHERE x IN (10);
+} {10 10 10}
+do_execsql_test in4-3.44 {
+  EXPLAIN
+  SELECT * FROM t3 WHERE x IN (10);
+} {~/OpenEphemeral/}
+do_execsql_test in4-3.45 {
+  SELECT * FROM t3 WHERE x NOT IN (10,11);
+} {1 1 1}
+do_execsql_test in4-3.46 {
+  EXPLAIN
+  SELECT * FROM t3 WHERE x NOT IN (10,11);
+} {/OpenEphemeral/}
+do_execsql_test in4-3.47 {
+  SELECT * FROM t3 WHERE x NOT IN (10);
+} {1 1 1}
+do_execsql_test in4-3.48 {
+  EXPLAIN
+  SELECT * FROM t3 WHERE x NOT IN (10);
+} {~/OpenEphemeral/}
+
+# Make sure that when "x IN (?)" is converted into "x==?" that collating
+# sequence and affinity computations do not get messed up.
+#
+do_execsql_test in4-4.1 {
+  CREATE TABLE t4a(a TEXT, b TEXT COLLATE nocase, c);
+  INSERT INTO t4a VALUES('ABC','abc',1);
+  INSERT INTO t4a VALUES('def','xyz',2);
+  INSERT INTO t4a VALUES('ghi','ghi',3);
+  SELECT c FROM t4a WHERE a=b ORDER BY c;
+} {3}
+do_execsql_test in4-4.2 {
+  SELECT c FROM t4a WHERE b=a ORDER BY c;
+} {1 3}
+do_execsql_test in4-4.3 {
+  SELECT c FROM t4a WHERE (a||'')=b ORDER BY c;
+} {1 3}
+do_execsql_test in4-4.4 {
+  SELECT c FROM t4a WHERE (a||'')=(b||'') ORDER BY c;
+} {3}
+do_execsql_test in4-4.5 {
+  SELECT c FROM t4a WHERE a IN (b) ORDER BY c;
+} {3}
+do_execsql_test in4-4.6 {
+  SELECT c FROM t4a WHERE (a||'') IN (b) ORDER BY c;
+} {3}
+
+
+do_execsql_test in4-4.11 {
+  CREATE TABLE t4b(a TEXT, b NUMERIC, c);
+  INSERT INTO t4b VALUES('1.0',1,4);
+  SELECT c FROM t4b WHERE a=b;
+} {4}
+do_execsql_test in4-4.12 {
+  SELECT c FROM t4b WHERE b=a;
+} {4}
+do_execsql_test in4-4.13 {
+  SELECT c FROM t4b WHERE +a=b;
+} {4}
+do_execsql_test in4-4.14 {
+  SELECT c FROM t4b WHERE a=+b;
+} {}
+do_execsql_test in4-4.15 {
+  SELECT c FROM t4b WHERE +b=a;
+} {}
+do_execsql_test in4-4.16 {
+  SELECT c FROM t4b WHERE b=+a;
+} {4}
+do_execsql_test in4-4.17 {
+  SELECT c FROM t4b WHERE a IN (b);
+} {}
+do_execsql_test in4-4.18 {
+  SELECT c FROM t4b WHERE b IN (a);
+} {4}
+do_execsql_test in4-4.19 {
+  SELECT c FROM t4b WHERE +b IN (a);
+} {}
+
+do_execsql_test in4-5.1 {
+  CREATE TABLE t5(c INTEGER PRIMARY KEY, d TEXT COLLATE nocase);
+  INSERT INTO t5 VALUES(17, 'fuzz');
+  SELECT 1 FROM t5 WHERE 'fuzz' IN (d);  -- match
+  SELECT 2 FROM t5 WHERE 'FUZZ' IN (d);  -- no match
+  SELECT 3 FROM t5 WHERE d IN ('fuzz');  -- match
+  SELECT 4 FROM t5 WHERE d IN ('FUZZ');  -- match
+} {1 3 4}
+
+# An expression of the form "x IN (y)" can be used as "x=y" by the
+# query planner when computing transitive constraints or to run the
+# query using an index on y.
+#
+do_execsql_test in4-6.1 {
+  CREATE TABLE t6a(a INTEGER PRIMARY KEY, b);
+  INSERT INTO t6a VALUES(1,2),(3,4),(5,6);
+  CREATE TABLE t6b(c INTEGER PRIMARY KEY, d);
+  INSERT INTO t6b VALUES(4,44),(5,55),(6,66);
+
+  SELECT * FROM t6a, t6b WHERE a=3 AND b IN (c);
+} {3 4 4 44}
+do_execsql_test in4-6.1-eqp {
+  EXPLAIN QUERY PLAN
+  SELECT * FROM t6a, t6b WHERE a=3 AND b IN (c);
+} {~/SCAN/}
+do_execsql_test in4-6.2 {
+  SELECT * FROM t6a, t6b WHERE a=3 AND c IN (b);
+} {3 4 4 44}
+do_execsql_test in4-6.2-eqp {
+  EXPLAIN QUERY PLAN
+  SELECT * FROM t6a, t6b WHERE a=3 AND c IN (b);
+} {~/SCAN/}
+
+
 finish_test
@@ -616,4 +616,24 @@ do_test limit-13.81 {
  db eval {SELECT z FROM v13c LIMIT 1 OFFSET 8}
 } {}

+do_execsql_test limit-14.1 {
+  SELECT 123 LIMIT 1 OFFSET 0
+} {123}
+do_execsql_test limit-14.2 {
+  SELECT 123 LIMIT 1 OFFSET 1
+} {}
+do_execsql_test limit-14.3 {
+  SELECT 123 LIMIT 0 OFFSET 0
+} {}
+do_execsql_test limit-14.4 {
+  SELECT 123 LIMIT 0 OFFSET 1
+} {}
+do_execsql_test limit-14.6 {
+  SELECT 123 LIMIT -1 OFFSET 0
+} {123}
+do_execsql_test limit-14.7 {
+  SELECT 123 LIMIT -1 OFFSET 1
+} {}
+
+
 finish_test
@@ -880,6 +880,28 @@ do_malloc_test 39 -tclprep {
  db close
 }

+reset_db
+add_test_utf16bin_collate db
+do_execsql_test 40.1 {
+  CREATE TABLE t1(a);
+  INSERT INTO t1 VALUES('fghij');
+  INSERT INTO t1 VALUES('pqrst');
+  INSERT INTO t1 VALUES('abcde');
+  INSERT INTO t1 VALUES('uvwxy');
+  INSERT INTO t1 VALUES('klmno');
+}
+do_execsql_test 40.2 {
+  SELECT * FROM t1 ORDER BY 1 COLLATE utf16bin;
+} {abcde fghij klmno pqrst uvwxy}
+do_faultsim_test 40.3 -faults oom-trans* -body {
+  execsql {
+    SELECT * FROM t1 ORDER BY 1 COLLATE utf16bin;
+  }
+} -test {
+  faultsim_test_result {0 {abcde fghij klmno pqrst uvwxy}} 
+  faultsim_integrity_check
+}
+
 # Ensure that no file descriptors were leaked.
 do_test malloc-99.X {
  catch {db close}
@@ -25,7 +25,6 @@ if {!$MEMDEBUG} {
   return
 }

-
 # Construct a test database
 #
 forcedelete test.db.bu
@@ -116,6 +115,28 @@ ifcapable stat3 {
  }
 }

+do_execsql_test 7.0 {
+  PRAGMA cache_size = 5;
+}
+do_faultsim_test 7 -faults oom-trans* -prep {
+  if {$iFail < 500} { set iFail 2000 }
+  if {$iFail > 1215} { set iFail 2000 }
+} -body {
+  execsql {
+    WITH r(x,y) AS (
+      SELECT 1, randomblob(100)
+      UNION ALL
+      SELECT x+1, randomblob(100) FROM r
+      LIMIT 1000
+    )
+    SELECT count(x), length(y) FROM r GROUP BY (x%5)
+  }
+} -test {
+  set res [list 200 100 200 100 200 100 200 100 200 100]
+  faultsim_test_result [list 0 $res]
+}
+
+
 # Ensure that no file descriptors were leaked.
 do_test malloc-99.X {
  catch {db close}
@@ -64,10 +64,28 @@ do_execsql_test 1.7 {
  EXPLAIN QUERY PLAN
  SELECT DISTINCT c, b, a FROM t1 WHERE +a=0;
 } {/B-TREE/}
-do_execsql_test 2.1 {
+
+# In some cases, it is faster to do repeated index lookups than it is to
+# sort.  But in other cases, it is faster to sort than to do repeated index
+# lookups.
+#
+do_execsql_test 2.1a {
+  CREATE TABLE t2(a,b,c);
+  CREATE INDEX t2bc ON t2(b,c);
+  ANALYZE;
+  INSERT INTO sqlite_stat1 VALUES('t1','t1bc','1000000 10 9');
+  INSERT INTO sqlite_stat1 VALUES('t2','t2bc','100 10 5');
+  ANALYZE sqlite_master;
+
+  EXPLAIN QUERY PLAN
+  SELECT * FROM t2 WHERE a=0 ORDER BY a, b, c;
+} {~/B-TREE/}
+do_execsql_test 2.1b {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE a=0 ORDER BY a, b, c;
-} {~/B-TREE/}
+} {/B-TREE/}
+
+
 do_execsql_test 2.2 {
  EXPLAIN QUERY PLAN
  SELECT * FROM t1 WHERE +a=0 ORDER BY a, b, c;
@@ -0,0 +1,183 @@
+# 2014-03-21
+#
+# 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 regression tests for SQLite library.  The
+# focus of this file is testing that the block-sort optimization.
+#
+
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+set ::testprefix orderby6
+
+# Run all tests twice.  Once with a normal table and a second time
+# with a WITHOUT ROWID table
+#
+foreach {tn rowidclause} {1 {} 2 {WITHOUT ROWID}} {
+
+  # Construct a table with 1000 rows and a split primary key
+  #
+  reset_db
+  do_test $tn.1 {
+    db eval "CREATE TABLE t1(a,b,c,PRIMARY KEY(b,c)) $rowidclause;"
+    db eval {
+      WITH RECURSIVE
+       cnt(x) AS (VALUES(1) UNION ALL SELECT x+1 FROM cnt WHERE x<1000)
+     INSERT INTO t1 SELECT x, x%40, x/40 FROM cnt;
+    }
+  } {}
+
+  # Run various ORDER BY queries that can benefit from block-sort.
+  # Compare the output to the same output using a full-sort enforced
+  # by adding + to each term of the ORDER BY clause.
+  #
+  do_execsql_test $tn.2 {
+    SELECT b,a,c FROM t1 ORDER BY b,a,c;
+  } [db eval {SELECT b,a,c FROM t1 ORDER BY +b,+a,+c}]
+  do_execsql_test $tn.3 {
+    SELECT b,a,c FROM t1 ORDER BY b,c DESC,a;
+  } [db eval {SELECT b,a,c FROM t1 ORDER BY +b,+c DESC,+a}]
+  do_execsql_test $tn.4 {
+    SELECT b,a,c FROM t1 ORDER BY b DESC,c,a;
+  } [db eval {SELECT b,a,c FROM t1 ORDER BY +b DESC,+c,+a}]
+  do_execsql_test $tn.5 {
+    SELECT b,a,c FROM t1 ORDER BY b DESC,a,c;
+  } [db eval {SELECT b,a,c FROM t1 ORDER BY +b DESC,+a,+c}]
+
+  # LIMIT and OFFSET clauses on block-sort queries.
+  #
+  do_execsql_test $tn.11 {
+    SELECT a FROM t1 ORDER BY b, a LIMIT 10 OFFSET 20;
+  } {840 880 920 960 1000 1 41 81 121 161}
+  do_execsql_test $tn.11x {
+    SELECT a FROM t1 ORDER BY +b, a LIMIT 10 OFFSET 20;
+  } {840 880 920 960 1000 1 41 81 121 161}
+
+  do_execsql_test $tn.12 {
+    SELECT a FROM t1 ORDER BY b DESC, a LIMIT 10 OFFSET 20;
+  } {839 879 919 959 999 38 78 118 158 198}
+  do_execsql_test $tn.12 {
+    SELECT a FROM t1 ORDER BY +b DESC, a LIMIT 10 OFFSET 20;
+  } {839 879 919 959 999 38 78 118 158 198}
+
+  do_execsql_test $tn.13 {
+    SELECT a FROM t1 ORDER BY b, a DESC LIMIT 10 OFFSET 45;
+  } {161 121 81 41 1 962 922 882 842 802}
+  do_execsql_test $tn.13x {
+    SELECT a FROM t1 ORDER BY +b, a DESC LIMIT 10 OFFSET 45;
+  } {161 121 81 41 1 962 922 882 842 802}
+
+  do_execsql_test $tn.14 {
+    SELECT a FROM t1 ORDER BY b DESC, a LIMIT 10 OFFSET 45;
+  } {838 878 918 958 998 37 77 117 157 197}
+  do_execsql_test $tn.14x {
+    SELECT a FROM t1 ORDER BY +b DESC, a LIMIT 10 OFFSET 45;
+  } {838 878 918 958 998 37 77 117 157 197}
+
+  # Many test cases where the LIMIT+OFFSET window is in various
+  # alignments with block-sort boundaries.
+  #
+  foreach {tx limit offset orderby} {
+     1  10 24 {+b,+a}
+     2  10 25 {+b,+a}
+     3  10 26 {+b,+a}
+     4  10 39 {+b,+a}
+     5  10 40 {+b,+a}
+     6  10 41 {+b,+a}
+     7  27 24 {+b,+a}
+     8  27 49 {+b,+a}
+     11 10 24 {+b DESC,+a}
+     12 10 25 {+b DESC,+a}
+     13 10 26 {+b DESC,+a}
+     14 10 39 {+b DESC,+a}
+     15 10 40 {+b DESC,+a}
+     16 10 41 {+b DESC,+a}
+     17 27 24 {+b DESC,+a}
+     18 27 49 {+b DESC,+a}
+     21 10 24 {+b,+a DESC}
+     22 10 25 {+b,+a DESC}
+     23 10 26 {+b,+a DESC}
+     24 10 39 {+b,+a DESC}
+     25 10 40 {+b,+a DESC}
+     26 10 41 {+b,+a DESC}
+     27 27 24 {+b,+a DESC}
+     28 27 49 {+b,+a DESC}
+     31 10 24 {+b DESC,+a DESC}
+     32 10 25 {+b DESC,+a DESC}
+     33 10 26 {+b DESC,+a DESC}
+     34 10 39 {+b DESC,+a DESC}
+     35 10 40 {+b DESC,+a DESC}
+     36 10 41 {+b DESC,+a DESC}
+     37 27 24 {+b DESC,+a DESC}
+     38 27 49 {+b DESC,+a DESC}
+  } {
+    set sql1 "SELECT a FROM t1 ORDER BY $orderby LIMIT $limit OFFSET $offset;"
+    set sql2 [string map {+ {}} $sql1]
+    # puts $sql2\n$sql1\n[db eval $sql2]
+    do_test $tn.21.$tx {db eval $::sql2} [db eval $sql1]
+  }
+
+  ########################################################################
+  # A second test table, t2, has many columns open to sorting.
+  do_test $tn.31 {
+    db eval "CREATE TABLE t2(a,b,c,d,e,f,PRIMARY KEY(b,c,d,e,f)) $rowidclause;"
+    db eval {
+      WITH RECURSIVE
+       cnt(x) AS (VALUES(0) UNION ALL SELECT x+1 FROM cnt WHERE x<242)
+     INSERT INTO t2 SELECT x,  x%3, (x/3)%3, (x/9)%3, (x/27)%3, (x/81)%3
+                      FROM cnt;
+    }
+  } {}
+
+  do_execsql_test $tn.32 {
+    SELECT a FROM t2 ORDER BY b,c,d,e,f;
+  } [db eval {SELECT a FROM t2 ORDER BY +b,+c,+d,+e,+f;}]
+  do_execsql_test $tn.33 {
+    SELECT a FROM t2 ORDER BY b,c,d,e,+f;
+  } [db eval {SELECT a FROM t2 ORDER BY +b,+c,+d,+e,+f;}]
+  do_execsql_test $tn.34 {
+    SELECT a FROM t2 ORDER BY b,c,d,+e,+f;
+  } [db eval {SELECT a FROM t2 ORDER BY +b,+c,+d,+e,+f;}]
+  do_execsql_test $tn.35 {
+    SELECT a FROM t2 ORDER BY b,c,+d,+e,+f;
+  } [db eval {SELECT a FROM t2 ORDER BY +b,+c,+d,+e,+f;}]
+  do_execsql_test $tn.36 {
+    SELECT a FROM t2 ORDER BY b,+c,+d,+e,+f;
+  } [db eval {SELECT a FROM t2 ORDER BY +b,+c,+d,+e,+f;}]
+
+  do_execsql_test $tn.37 {
+    SELECT a FROM t2 ORDER BY b,c,d,e,f DESC;
+  } [db eval {SELECT a FROM t2 ORDER BY +b,+c,+d,+e,+f DESC;}]
+  do_execsql_test $tn.38 {
+    SELECT a FROM t2 ORDER BY b,c,d,e DESC,f;
+  } [db eval {SELECT a FROM t2 ORDER BY +b,+c,+d,+e DESC,+f;}]
+  do_execsql_test $tn.39 {
+    SELECT a FROM t2 ORDER BY b,c,d DESC,e,f;
+  } [db eval {SELECT a FROM t2 ORDER BY +b,+c,+d DESC,+e,+f;}]
+  do_execsql_test $tn.40 {
+    SELECT a FROM t2 ORDER BY b,c DESC,d,e,f;
+  } [db eval {SELECT a FROM t2 ORDER BY +b,+c DESC,+d,+e,+f;}]
+  do_execsql_test $tn.41 {
+    SELECT a FROM t2 ORDER BY b DESC,c,d,e,f;
+  } [db eval {SELECT a FROM t2 ORDER BY +b DESC,+c,+d,+e,+f;}]
+
+  do_execsql_test $tn.42 {
+    SELECT a FROM t2 ORDER BY b DESC,c DESC,d,e,f LIMIT 31;
+  } [db eval {SELECT a FROM t2 ORDER BY +b DESC,+c DESC,+d,+e,+f LIMIT 31}]
+  do_execsql_test $tn.43 {
+    SELECT a FROM t2 ORDER BY b,c,d,e,f DESC LIMIT 8 OFFSET 7;
+  } [db eval {SELECT a FROM t2 ORDER BY +b,+c,+d,+e,+f DESC LIMIT 8 OFFSET 7}]
+
+
+}
+
+
+
+finish_test
@@ -112,6 +112,7 @@ set allquicktests [test_set $alltests -exclude {
  incrvacuum_ioerr.test autovacuum_crash.test btree8.test shared_err.test
  vtab_err.test walslow.test walcrash.test walcrash3.test
  walthread.test rtree3.test indexfault.test securedel2.test
+  sort3.test
 }]
 if {[info exists ::env(QUICKTEST_INCLUDE)]} {
  set allquicktests [concat $allquicktests $::env(QUICKTEST_INCLUDE)]
@@ -209,4 +209,42 @@ do_execsql_test skipscan1-4.1 {
  SELECT i FROM t4 WHERE h=8;
 } {9 9 9 9 9 9 9 9}

+# Make sure skip-scan cost computation in the query planner takes into
+# account the fact that the seek must occur multiple times.
+#
+# Prior to 2014-03-10, the costs were computed incorrectly which would
+# cause index t5i2 to be used instead of t5i1 on the skipscan1-5.3.
+#
+do_execsql_test skipscan1-5.1 {
+  CREATE TABLE t5(
+    id INTEGER PRIMARY KEY,
+    loc TEXT,
+    lang INTEGER,
+    utype INTEGER,
+    xa INTEGER,
+    xd INTEGER,
+    xh INTEGER
+  );
+  CREATE INDEX t5i1 on t5(loc, xh, xa, utype, lang);
+  CREATE INDEX t5i2 ON t5(xd,loc,utype,lang);
+  EXPLAIN QUERY PLAN
+    SELECT xh, loc FROM t5 WHERE loc >= 'M' AND loc < 'N';
+} {/.*COVERING INDEX t5i1 .*/}
+do_execsql_test skipscan1-5.2 {
+  ANALYZE;
+  DELETE FROM sqlite_stat1;
+  DROP TABLE IF EXISTS sqlite_stat4;
+  DROP TABLE IF EXISTS sqlite_stat3;
+  INSERT INTO sqlite_stat1 VALUES('t5','t5i1','2702931 3 2 2 2 2');
+  INSERT INTO sqlite_stat1 VALUES('t5','t5i2','2702931 686 2 2 2');
+  ANALYZE sqlite_master;
+} {}
+db cache flush
+do_execsql_test skipscan1-5.3 {
+  EXPLAIN QUERY PLAN
+    SELECT xh, loc FROM t5 WHERE loc >= 'M' AND loc < 'N';
+} {/.*COVERING INDEX t5i1 .*/}
+
+
+
 finish_test
@@ -464,4 +464,26 @@ do_test sort-12.1 {
  }
 } {1 2 xxx 1 3 yyy 1 1 zzz}

+#-------------------------------------------------------------------------
+# Check that the sorter in vdbesort.c sorts in a stable fashion.
+#
+do_execsql_test sort-13.0 {
+  CREATE TABLE t10(a, b);
+}
+do_test sort-13.1 {
+  db transaction {
+    for {set i 0} {$i < 100000} {incr i} {
+      execsql { INSERT INTO t10 VALUES( $i/10, $i%10 ) }
+    }
+  }
+} {}
+do_execsql_test sort-13.2 {
+  SELECT a, b FROM t10 ORDER BY a;
+} [db eval {SELECT a, b FROM t10 ORDER BY a, b}]
+do_execsql_test sort-13.3 {
+  PRAGMA cache_size = 5;
+  SELECT a, b FROM t10 ORDER BY a;
+} [db eval {SELECT a, b FROM t10 ORDER BY a, b}]
+
+
 finish_test
@@ -0,0 +1,55 @@
+# 2014 March 25.
+#
+# 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 regression tests for SQLite library. 
+#
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+set testprefix sort2
+
+db close
+sqlite3_shutdown
+sqlite3_config_worker_threads 7
+reset_db
+
+do_execsql_test 1 {
+  PRAGMA cache_size = 5;
+  WITH r(x,y) AS (
+    SELECT 1, randomblob(100)
+    UNION ALL
+    SELECT x+1, randomblob(100) FROM r
+    LIMIT 100000
+  )
+  SELECT count(x), length(y) FROM r GROUP BY (x%5)
+} {
+  20000 100 20000 100 20000 100 20000 100 20000 100
+}
+
+do_execsql_test 2.1 {
+  CREATE TABLE t1(a, b);
+  WITH r(x,y) AS (
+    SELECT 1, randomblob(100)
+    UNION ALL
+    SELECT x+1, randomblob(100) FROM r
+    LIMIT 10000
+  ) INSERT INTO t1 SELECT * FROM r;
+}
+
+do_execsql_test 2.2 {
+  CREATE UNIQUE INDEX i1 ON t1(b, a);
+}
+
+db close
+sqlite3_shutdown
+sqlite3_config_worker_threads 0
+sqlite3_initialize
+finish_test
+
@@ -0,0 +1,63 @@
+# 2014 March 25.
+#
+# 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 regression tests for SQLite library. 
+#
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+set testprefix sort3
+
+# Sort roughly 20MB of data. Once with a mmap limit of 5MB and once without.
+#
+foreach {itest limit} {
+  1 5000000
+  2 0x7FFFFFFF
+} {
+  sqlite3_test_control SQLITE_TESTCTRL_SORTER_MMAP db $limit
+  do_execsql_test 1.$itest {
+    WITH r(x,y) AS (
+        SELECT 1, randomblob(1000)
+        UNION ALL
+        SELECT x+1, randomblob(1000) FROM r
+        LIMIT 20000
+    )
+    SELECT count(*), sum(length(y)) FROM r GROUP BY (x%5);
+  } {
+    4000 4000000 
+    4000 4000000 
+    4000 4000000 
+    4000 4000000 
+    4000 4000000
+  }
+}
+
+# Sort more than 2GB of data. At one point this was causing a problem.
+# This test might take one minute or more to run.
+#
+do_execsql_test 2 {
+  PRAGMA cache_size = 20000;
+  WITH r(x,y) AS (
+    SELECT 1, randomblob(1000)
+    UNION ALL
+    SELECT x+1, randomblob(1000) FROM r
+    LIMIT 2200000
+  )
+  SELECT count(*), sum(length(y)) FROM r GROUP BY (x%5);
+} {
+  440000 440000000 
+  440000 440000000 
+  440000 440000000 
+  440000 440000000 
+  440000 440000000
+}
+
+finish_test
+
@@ -474,7 +474,7 @@ void testset_main(void){
  speedtest1_end_test();


-  n = g.szTest/2;
+  n = 25;
  speedtest1_begin_test(130, "%d SELECTS, numeric BETWEEN, unindexed", n);
  speedtest1_exec("BEGIN");
  speedtest1_prepare(
@@ -492,7 +492,7 @@ void testset_main(void){
  speedtest1_end_test();


-  n = g.szTest/5;
+  n = 10;
  speedtest1_begin_test(140, "%d SELECTS, LIKE, unindexed", n);
  speedtest1_exec("BEGIN");
  speedtest1_prepare(
@@ -512,6 +512,45 @@ void testset_main(void){
  speedtest1_end_test();


+  n = 10;
+  speedtest1_begin_test(142, "%d SELECTS w/ORDER BY, unindexed", n);
+  speedtest1_exec("BEGIN");
+  speedtest1_prepare(
+    "SELECT a, b, c FROM t1 WHERE c LIKE ?1\n"
+    " ORDER BY a; -- %d times", n
+  );
+  for(i=1; i<=n; i++){
+    x1 = speedtest1_random()%maxb;
+    zNum[0] = '%';
+    len = speedtest1_numbername(i, zNum+1, sizeof(zNum)-2);
+    zNum[len] = '%';
+    zNum[len+1] = 0;
+    sqlite3_bind_text(g.pStmt, 1, zNum, len, SQLITE_STATIC);
+    speedtest1_run();
+  }
+  speedtest1_exec("COMMIT");
+  speedtest1_end_test();
+
+  n = 10; //g.szTest/5;
+  speedtest1_begin_test(145, "%d SELECTS w/ORDER BY and LIMIT, unindexed", n);
+  speedtest1_exec("BEGIN");
+  speedtest1_prepare(
+    "SELECT a, b, c FROM t1 WHERE c LIKE ?1\n"
+    " ORDER BY a LIMIT 10; -- %d times", n
+  );
+  for(i=1; i<=n; i++){
+    x1 = speedtest1_random()%maxb;
+    zNum[0] = '%';
+    len = speedtest1_numbername(i, zNum+1, sizeof(zNum)-2);
+    zNum[len] = '%';
+    zNum[len+1] = 0;
+    sqlite3_bind_text(g.pStmt, 1, zNum, len, SQLITE_STATIC);
+    speedtest1_run();
+  }
+  speedtest1_exec("COMMIT");
+  speedtest1_end_test();
+
+
  speedtest1_begin_test(150, "CREATE INDEX five times");
  speedtest1_exec("BEGIN;");
  speedtest1_exec("CREATE UNIQUE INDEX t1b ON t1(b);");
@@ -61,6 +61,7 @@ foreach s {
    fcntl read pread write pwrite fchmod fallocate
    pread64 pwrite64 unlink openDirectory mkdir rmdir 
    statvfs fchown umask mmap munmap mremap
+    getpagesize
 } {
  if {[test_syscall exists $s]} {lappend syscall_list $s}
 }
@@ -1076,6 +1076,7 @@ proc explain_i {sql {db db}} {
  foreach opcode {
      Seek SeekGe SeekGt SeekLe SeekLt NotFound Last Rewind
      NoConflict Next Prev VNext VPrev VFilter
+      SorterSort SorterNext
  } {
    set color($opcode) $B
  }
@@ -1098,6 +1099,7 @@ proc explain_i {sql {db db}} {

    if {$opcode=="Next"  || $opcode=="Prev" 
     || $opcode=="VNext" || $opcode=="VPrev"
+     || $opcode=="SorterNext"
    } {
      for {set i $p2} {$i<$addr} {incr i} {
        incr x($i) 2
@@ -0,0 +1,93 @@
+# 2014-03-24
+#
+# 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.
+#
+#***********************************************************************
+# 
+# Tests to verify that arithmetic operators do not change the type of
+# input operands.  Ticket [a8a0d2996a]
+#
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+set testprefix tkt-a8a0d2996a
+
+do_execsql_test 1.0 {
+  CREATE TABLE t(x,y);
+  INSERT INTO t VALUES('1','1');
+  SELECT typeof(x), typeof(y) FROM t WHERE 1=x+0 AND y=='1';
+} {text text}
+do_execsql_test 1.1 {
+  SELECT typeof(x), typeof(y) FROM t WHERE 1=x-0 AND y=='1';
+} {text text}
+do_execsql_test 1.2 {
+  SELECT typeof(x), typeof(y) FROM t WHERE 1=x*1 AND y=='1';
+} {text text}
+do_execsql_test 1.3 {
+  SELECT typeof(x), typeof(y) FROM t WHERE 1=x/1 AND y=='1';
+} {text text}
+do_execsql_test 1.4 {
+  SELECT typeof(x), typeof(y) FROM t WHERE 1=x%4 AND y=='1';
+} {text text}
+
+do_execsql_test 2.0 {
+  UPDATE t SET x='1xyzzy';
+  SELECT typeof(x), typeof(y) FROM t WHERE 1=x+0 AND y=='1';
+} {text text}
+do_execsql_test 2.1 {
+  SELECT typeof(x), typeof(y) FROM t WHERE 1=x-0 AND y=='1';
+} {text text}
+do_execsql_test 2.2 {
+  SELECT typeof(x), typeof(y) FROM t WHERE 1=x*1 AND y=='1';
+} {text text}
+do_execsql_test 2.3 {
+  SELECT typeof(x), typeof(y) FROM t WHERE 1=x/1 AND y=='1';
+} {text text}
+do_execsql_test 2.4 {
+  SELECT typeof(x), typeof(y) FROM t WHERE 1=x%4 AND y=='1';
+} {text text}
+
+
+do_execsql_test 3.0 {
+  UPDATE t SET x='1.0';
+  SELECT typeof(x), typeof(y) FROM t WHERE 1=x+0 AND y=='1';
+} {text text}
+do_execsql_test 3.1 {
+  SELECT typeof(x), typeof(y) FROM t WHERE 1=x-0 AND y=='1';
+} {text text}
+do_execsql_test 3.2 {
+  SELECT typeof(x), typeof(y) FROM t WHERE 1=x*1 AND y=='1';
+} {text text}
+do_execsql_test 3.3 {
+  SELECT typeof(x), typeof(y) FROM t WHERE 1=x/1 AND y=='1';
+} {text text}
+do_execsql_test 3.4 {
+  SELECT typeof(x), typeof(y) FROM t WHERE 1=x%4 AND y=='1';
+} {text text}
+
+do_execsql_test 4.0 {
+  SELECT 1+1.;
+} {2.0}
+do_execsql_test 4.1 {
+  SELECT '1.23e64'/'1.0000e+62';
+} {123.0}
+do_execsql_test 4.2 {
+  SELECT '100x'+'-2y';
+} {98}
+do_execsql_test 4.3 {
+  SELECT '100x'+'4.5y';
+} {104.5}
+do_execsql_test 4.4 {
+  SELECT '-9223372036854775807x'-'1x';
+} {-9.22337203685478e+18}
+do_execsql_test 4.5 {
+  SELECT '9223372036854775806x'+'1x';
+} {9.22337203685478e+18}
+do_execsql_test 4.6 {
+  SELECT '1234x'/'10y';
+} {123.4}
@@ -15,6 +15,7 @@

 set testdir [file dirname $argv0]
 source $testdir/tester.tcl
+set testprefix vtab_shared

 ifcapable !vtab||!shared_cache {
  finish_test
@@ -228,5 +229,51 @@ do_test vtab_shared_1.15.3 {

 db close
 db2 close
+
+#---------------------------------------------------------------
+# Test calling sqlite3_close() with vtabs on the disconnect list.
+#
+ifcapable rtree {
+  reset_db
+  do_test 2.1.1 {
+    sqlite3 db  test.db
+    sqlite3 db2 test.db
+  
+    # Create a virtual table using [db]. 
+    execsql {
+      CREATE VIRTUAL TABLE rt USING rtree(id, x1, x2);
+      INSERT INTO rt VALUES(1, 2 ,3);
+      SELECT * FROM rt;
+    }
+  
+    # Drop the virtual table using [db2]. The sqlite3_vtab object belonging
+    # to [db] is moved to the sqlite3.pDisconnect list.
+    execsql { DROP TABLE rt } db2
+  
+    # Immediately close [db]. At one point this would fail due to the 
+    # unfinalized statements held by the un-xDisconnect()ed sqlite3_vtab.
+    db close
+  } {}
+  db2 close
+}
+
+ifcapable fts3 {
+  # Same test as above, except using fts3 instead of rtree.
+  reset_db
+  do_test 2.2.1 {
+    sqlite3 db  test.db
+    sqlite3 db2 test.db
+    execsql {
+      CREATE VIRTUAL TABLE ft USING fts3;
+      INSERT INTO ft VALUES('hello world');
+      SELECT * FROM ft;
+    } 
+    execsql { DROP TABLE ft } db2
+    db close
+  } {}
+  db2 close
+}
+
 sqlite3_enable_shared_cache 0
 finish_test
+
@@ -1574,4 +1574,17 @@ sqlite3_shutdown
 test_sqlite3_log
 sqlite3_initialize

+# Make sure PRAGMA journal_mode=WAL works with ATTACHED databases in
+# all journal modes.
+#
+foreach mode {OFF MEMORY PERSIST DELETE TRUNCATE WAL} {
+  delete_file test.db test2.db
+  sqlite3 db test.db
+  do_test wal-25.$mode {
+    db eval "PRAGMA journal_mode=$mode"
+    db eval {ATTACH 'test2.db' AS t2; PRAGMA journal_mode=WAL;}
+  } {wal}
+  db close
+}
+
 finish_test
@@ -0,0 +1,51 @@
+# 2010 April 13
+#
+# 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 regression tests for SQLite library.  The
+# focus of this file is testing the operation of the library in
+# "PRAGMA journal_mode=WAL" mode.
+#
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+set testprefix wal64k
+
+ifcapable !wal {finish_test ; return }
+
+if {$tcl_platform(platform) != "unix"} {
+  finish_test
+  return
+}
+
+db close
+test_syscall pagesize 65536
+sqlite3 db test.db
+
+do_execsql_test 1.0 { 
+  PRAGMA journal_mode = WAL;
+  CREATE TABLE t1(x);
+  CREATE INDEX i1 ON t1(x);
+} {wal}
+do_test 1.1 { file size test.db-shm } {65536}
+
+do_test 1.2 {
+  execsql BEGIN
+  while {[file size test.db-shm]==65536} {
+    execsql { INSERT INTO t1 VALUES( randstr(900,1100) ) }
+  }
+  execsql COMMIT
+  file size test.db-shm
+} {131072}
+
+integrity_check 1.3
+
+db close
+test_syscall pagesize -1
+finish_test
@@ -95,7 +95,7 @@ do_eqp_test whereG-1.5 {
   WHERE cname LIKE '%bach%'
     AND composer.cid=track.cid
     AND album.aid=track.aid;
-} {/.*track.*composer.*album.*/}
+} {/.*track.*(composer.*album|album.*composer).*/}
 do_execsql_test whereG-1.6 {
  SELECT DISTINCT aname
    FROM album, composer, track
@@ -110,7 +110,7 @@ do_eqp_test whereG-1.7 {
   WHERE cname LIKE '%bach%'
     AND unlikely(composer.cid=track.cid)
     AND unlikely(album.aid=track.aid);
-} {/.*track.*composer.*album.*/}
+} {/.*track.*(composer.*album|album.*composer).*/}
 do_execsql_test whereG-1.8 {
  SELECT DISTINCT aname
    FROM album, composer, track
@@ -166,5 +166,18 @@ do_eqp_test whereG-3.4 {
  SELECT * FROM a, b WHERE a2=5 AND a1=b1;
 } {/.*SCAN TABLE a.*SEARCH TABLE b USING INDEX .*b_1 .b1=..*/}

+# Ticket [1e64dd782a126f48d78c43a664844a41d0e6334e]:
+# Incorrect result in a nested GROUP BY/DISTINCT due to the use of an OP_SCopy
+# where an OP_Copy was needed.
+#
+do_execsql_test whereG-4.0 {
+  CREATE TABLE t4(x);
+  INSERT INTO t4 VALUES('right'),('wrong');
+  SELECT DISTINCT x
+   FROM (SELECT x FROM t4 GROUP BY x)
+   WHERE x='right'
+   ORDER BY x;
+} {right}
+

 finish_test
@@ -0,0 +1,139 @@
+# 2014-03-31
+#
+# 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.
+#
+#***********************************************************************
+# 
+# Test cases for query planning decisions where one candidate index
+# covers a proper superset of the WHERE clause terms of another
+# candidate index.
+#
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+
+do_execsql_test whereH-1.1 {
+  CREATE TABLE t1(a,b,c,d);
+  CREATE INDEX t1abc ON t1(a,b,c);
+  CREATE INDEX t1bc ON t1(b,c);
+
+  EXPLAIN QUERY PLAN
+  SELECT d FROM t1 WHERE a=? AND b=? AND c>=? ORDER BY c;
+} {/INDEX t1abc /}
+do_execsql_test whereH-1.2 {
+  EXPLAIN QUERY PLAN
+  SELECT d FROM t1 WHERE a=? AND b=? AND c>=? ORDER BY c;
+} {~/TEMP B-TREE FOR ORDER BY/}
+
+do_execsql_test whereH-2.1 {
+  DROP TABLE t1;
+  CREATE TABLE t1(a,b,c,d);
+  CREATE INDEX t1bc ON t1(b,c);
+  CREATE INDEX t1abc ON t1(a,b,c);
+
+  EXPLAIN QUERY PLAN
+  SELECT d FROM t1 WHERE a=? AND b=? AND c>=? ORDER BY c;
+} {/INDEX t1abc /}
+do_execsql_test whereH-2.2 {
+  EXPLAIN QUERY PLAN
+  SELECT d FROM t1 WHERE a=? AND b=? AND c>=? ORDER BY c;
+} {~/TEMP B-TREE FOR ORDER BY/}
+
+do_execsql_test whereH-3.1 {
+  DROP TABLE t1;
+  CREATE TABLE t1(a,b,c,d,e);
+  CREATE INDEX t1cd ON t1(c,d);
+  CREATE INDEX t1bcd ON t1(b,c,d);
+  CREATE INDEX t1abcd ON t1(a,b,c,d);
+
+  EXPLAIN QUERY PLAN
+  SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d;
+} {/INDEX t1abcd /}
+do_execsql_test whereH-3.2 {
+  EXPLAIN QUERY PLAN
+  SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d;
+} {~/TEMP B-TREE FOR ORDER BY/}
+
+do_execsql_test whereH-4.1 {
+  DROP TABLE t1;
+  CREATE TABLE t1(a,b,c,d,e);
+  CREATE INDEX t1cd ON t1(c,d);
+  CREATE INDEX t1abcd ON t1(a,b,c,d);
+  CREATE INDEX t1bcd ON t1(b,c,d);
+
+  EXPLAIN QUERY PLAN
+  SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d;
+} {/INDEX t1abcd /}
+do_execsql_test whereH-4.2 {
+  EXPLAIN QUERY PLAN
+  SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d;
+} {~/TEMP B-TREE FOR ORDER BY/}
+
+do_execsql_test whereH-5.1 {
+  DROP TABLE t1;
+  CREATE TABLE t1(a,b,c,d,e);
+  CREATE INDEX t1bcd ON t1(b,c,d);
+  CREATE INDEX t1cd ON t1(c,d);
+  CREATE INDEX t1abcd ON t1(a,b,c,d);
+
+  EXPLAIN QUERY PLAN
+  SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d;
+} {/INDEX t1abcd /}
+do_execsql_test whereH-5.2 {
+  EXPLAIN QUERY PLAN
+  SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d;
+} {~/TEMP B-TREE FOR ORDER BY/}
+
+do_execsql_test whereH-6.1 {
+  DROP TABLE t1;
+  CREATE TABLE t1(a,b,c,d,e);
+  CREATE INDEX t1bcd ON t1(b,c,d);
+  CREATE INDEX t1abcd ON t1(a,b,c,d);
+  CREATE INDEX t1cd ON t1(c,d);
+
+  EXPLAIN QUERY PLAN
+  SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d;
+} {/INDEX t1abcd /}
+do_execsql_test whereH-6.2 {
+  EXPLAIN QUERY PLAN
+  SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d;
+} {~/TEMP B-TREE FOR ORDER BY/}
+
+do_execsql_test whereH-7.1 {
+  DROP TABLE t1;
+  CREATE TABLE t1(a,b,c,d,e);
+  CREATE INDEX t1abcd ON t1(a,b,c,d);
+  CREATE INDEX t1bcd ON t1(b,c,d);
+  CREATE INDEX t1cd ON t1(c,d);
+
+  EXPLAIN QUERY PLAN
+  SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d;
+} {/INDEX t1abcd /}
+do_execsql_test whereH-7.2 {
+  EXPLAIN QUERY PLAN
+  SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d;
+} {~/TEMP B-TREE FOR ORDER BY/}
+
+do_execsql_test whereH-8.1 {
+  DROP TABLE t1;
+  CREATE TABLE t1(a,b,c,d,e);
+  CREATE INDEX t1abcd ON t1(a,b,c,d);
+  CREATE INDEX t1cd ON t1(c,d);
+  CREATE INDEX t1bcd ON t1(b,c,d);
+
+  EXPLAIN QUERY PLAN
+  SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d;
+} {/INDEX t1abcd /}
+do_execsql_test whereH-8.2 {
+  EXPLAIN QUERY PLAN
+  SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d;
+} {~/TEMP B-TREE FOR ORDER BY/}
+
+
+
+finish_test
@@ -385,6 +385,33 @@ do_execsql_test 7.5 {
  )
 } {14 28 42}

+#-------------------------------------------------------------------------
+# At one point the following was causing an assertion failure and a 
+# memory leak.
+#
+do_execsql_test 8.1 {
+  CREATE TABLE t7(y);
+  INSERT INTO t7 VALUES(NULL);
+  CREATE VIEW v AS SELECT * FROM t7 ORDER BY y;
+}
+
+do_execsql_test 8.2 {
+  WITH q(a) AS (
+    SELECT 1
+    UNION 
+    SELECT a+1 FROM q, v WHERE a<5
+  )
+  SELECT * FROM q;
+} {1 2 3 4 5}
+
+do_execsql_test 8.3 {
+  WITH q(a) AS (
+    SELECT 1
+    UNION ALL
+    SELECT a+1 FROM q, v WHERE a<5
+  )
+  SELECT * FROM q;
+} {1 2 3 4 5}


 finish_test
@@ -17,13 +17,7 @@
 **
 **      ./LogEst ARGS
 **
-** Arguments:
-**
-**    'x'    Multiple the top two elements of the stack
-**    '+'    Add the top two elements of the stack
-**    NUM    Convert NUM from integer to LogEst and push onto the stack
-**   ^NUM    Interpret NUM as a LogEst and push onto stack.
-**
+** See the showHelp() routine for a description of valid arguments.
 ** Examples:
 **
 ** To convert 123 from LogEst to integer:
@@ -97,12 +91,31 @@ static LogEst logEstFromDouble(double x){
  return e*10;
 }

+int isInteger(const char *z){
+  while( z[0]>='0' && z[0]<='9' ) z++;
+  return z[0]==0;
+}
+
 int isFloat(const char *z){
-  while( z[0] ){
-    if( z[0]=='.' || z[0]=='E' || z[0]=='e' ) return 1;
-    z++;
-  }
-  return 0;
+  char c;
+  while( ((c=z[0])>='0' && c<='9') || c=='.' || c=='E' || c=='e'
+          || c=='+' || c=='-'  ) z++;
+  return z[0]==0;
+}
+
+static void showHelp(const char *zArgv0){
+  printf("Usage: %s ARGS...\n", zArgv0);
+  printf("Arguments:\n"
+    "  NUM    Convert NUM from integer to LogEst and push onto the stack\n"
+    " ^NUM    Interpret NUM as a LogEst and push onto stack\n"
+    "  x      Multiple the top two elements of the stack\n"
+    "  +      Add the top two elements of the stack\n"
+    "  dup    Dupliate the top element on the stack\n"
+    "  inv    Take the reciprocal of the top of stack.  N = 1/N.\n"
+    "  log    Find the LogEst of the number on top of stack\n"
+    "  nlogn  Compute NlogN where N is the top of stack\n"
+  );
+  exit(1);
 }

 int main(int argc, char **argv){
@@ -111,30 +124,43 @@ int main(int argc, char **argv){
  LogEst a[100];
  for(i=1; i<argc; i++){
    const char *z = argv[i];
-    if( z[0]=='+' ){
+    if( strcmp(z,"+")==0 ){
      if( n>=2 ){
        a[n-2] = logEstAdd(a[n-2],a[n-1]);
        n--;
      }
-    }else if( z[0]=='x' ){
+    }else if( strcmp(z,"x")==0 ){
      if( n>=2 ){
        a[n-2] = logEstMultiply(a[n-2],a[n-1]);
        n--;
      }
+    }else if( strcmp(z,"dup")==0 ){
+      if( n>0 ){
+        a[n] = a[n-1];
+        n++;
+      }
+    }else if( strcmp(z,"log")==0 ){
+      if( n>0 ) a[n-1] = logEstFromInteger(a[n-1]) - 33;
+    }else if( strcmp(z,"nlogn")==0 ){
+      if( n>0 ) a[n-1] += logEstFromInteger(a[n-1]) - 33;
+    }else if( strcmp(z,"inv")==0 ){
+      if( n>0 ) a[n-1] = -a[n-1];
    }else if( z[0]=='^' ){
      a[n++] = atoi(z+1);
-    }else if( isFloat(z) ){
+    }else if( isInteger(z) ){
+      a[n++] = logEstFromInteger(atoi(z));
+    }else if( isFloat(z) && z[0]!='-' ){
      a[n++] = logEstFromDouble(atof(z));
    }else{
-      a[n++] = logEstFromInteger(atoi(z));
+      showHelp(argv[0]);
    }
  }
  for(i=n-1; i>=0; i--){
    if( a[i]<0 ){
-      printf("%d (%f)\n", a[i], 1.0/(double)logEstToInt(-a[i]));
+      printf("%5d (%f)\n", a[i], 1.0/(double)logEstToInt(-a[i]));
    }else{
      sqlite3_uint64 x = logEstToInt(a[i]+100)*100/1024;
-      printf("%d (%lld.%02lld)\n", a[i], x/100, x%100);
+      printf("%5d (%lld.%02lld)\n", a[i], x/100, x%100);
    }
  }
  return 0;
@@ -237,6 +237,7 @@ foreach file {
   malloc.c
   printf.c
   random.c
+   threads.c
   utf.c
   util.c
   hash.c
@@ -249,6 +249,7 @@ foreach file {
   malloc.c
   printf.c
   random.c
+   threads.c
   utf.c
   util.c
   hash.c
@@ -1 +1 @@
 .8.4
 .8.5