From 580d7dc71d0a5f820df8062d76e8b27590ff5fcc Mon Sep 17 00:00:00 2001
From: drh <drh@noemail.net>
Date: Tue, 9 Jul 2013 15:56:44 +0000
Subject: [PATCH 1/5] Adjust the costs in the xBestIndex function of the
 spellfix1 virtual table to force the use of the MATCH term if it is
 available.

FossilOrigin-Name: f003bea9fe1b79e2b4d18fbef86c1d8f0f60e4b6
---
 ext/misc/spellfix.c |  4 ++--
 manifest            | 12 ++++++------
 manifest.uuid       |  2 +-
 3 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/ext/misc/spellfix.c b/ext/misc/spellfix.c
index eb5442ed2f..7d4f5e9870 100644
--- a/ext/misc/spellfix.c
+++ b/ext/misc/spellfix.c
@@ -2148,10 +2148,10 @@ static int spellfix1BestIndex(sqlite3_vtab *tab, sqlite3_index_info *pIdxInfo){
       pIdxInfo->aConstraintUsage[iDistTerm].argvIndex = idx++;
       pIdxInfo->aConstraintUsage[iDistTerm].omit = 1;
     }
-    pIdxInfo->estimatedCost = (double)10000;
+    pIdxInfo->estimatedCost = 1e5;
   }else{
     pIdxInfo->idxNum = 0;
-    pIdxInfo->estimatedCost = (double)10000000;
+    pIdxInfo->estimatedCost = 1e50;
   }
   return SQLITE_OK;
 }
diff --git a/manifest b/manifest
index 048d682c0a..4f18895950 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Modify\sseveral\sextensions\sto\suse\sthe\snew\sexported\sfunction\snaming.\s\nFix\ssome\sshared\slibrary\scompilation\sissues.
-D 2013-07-09T12:36:30.399
+C Adjust\sthe\scosts\sin\sthe\sxBestIndex\sfunction\sof\sthe\sspellfix1\svirtual\stable\nto\sforce\sthe\suse\sof\sthe\sMATCH\sterm\sif\sit\sis\savailable.
+D 2013-07-09T15:56:44.605
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 5e41da95d92656a5004b03d3576e8b226858a28e
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -114,7 +114,7 @@ F ext/misc/nextchar.c 80ba262d23238efcfcb3d72d71aa4513098e26a6
 F ext/misc/percentile.c bcbee3c061b884eccb80e21651daaae8e1e43c63
 F ext/misc/regexp.c c25c65fe775f5d9801fb8573e36ebe73f2c0c2e0
 F ext/misc/rot13.c 1ac6f95f99b575907b9b09c81a349114cf9be45a
-F ext/misc/spellfix.c 6d7ce6105a4b7729f6c44ccdf1ab7e80d9707c02
+F ext/misc/spellfix.c 5e1d547e9a2aed13897fa91bac924333f62fd2d9
 F ext/misc/vtshim.c 5fb6be7fe37659a8cbd1e16982d74cceacbc4543
 F ext/misc/wholenumber.c 784b12543d60702ebdd47da936e278aa03076212
 F ext/rtree/README 6315c0d73ebf0ec40dedb5aa0e942bc8b54e3761
@@ -1101,7 +1101,7 @@ F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh fbc018d67fd7395f440c28f33ef0f94420226381
 F tool/wherecosttest.c f407dc4c79786982a475261866a161cd007947ae
 F tool/win/sqlite.vsix 97894c2790eda7b5bce3cc79cb2a8ec2fde9b3ac
-P 52a49cbc1621094b2fe2b021209b768d29e0426b f2ab8747825ab5131ffab174aa0ffe5e474f6811
-R f4d92c08ade3445d4abd0e6606f44c69
+P 1e39f85077f1f2b96c3a656c5b6334bafb005908
+R 2ea622f28aaf7cdeeb856cb215ef9fb3
 U drh
-Z 1ae873026565d0007b698ed53e93eb8a
+Z 80087d9cff19d8b6d80e8c14572ef089
diff --git a/manifest.uuid b/manifest.uuid
index b2a7e956cd..1984d58a78 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-1e39f85077f1f2b96c3a656c5b6334bafb005908
\ No newline at end of file
+f003bea9fe1b79e2b4d18fbef86c1d8f0f60e4b6
\ No newline at end of file

From 49afe3aaa067eb050d0e831d351683c8251cba42 Mon Sep 17 00:00:00 2001
From: drh <drh@noemail.net>
Date: Wed, 10 Jul 2013 03:05:14 +0000
Subject: [PATCH 2/5] Run progress callback checks less frequently in the main
 VDBE evaluation loop.  This makes up for the extra CPU cycles used to
 increment the cycle counter for SQLITE_STMTSTATUS_VM_STEP.

FossilOrigin-Name: 3e8b02011db2f393d4850115a471709b0a88594f
---
 manifest           | 14 ++++-----
 manifest.uuid      |  2 +-
 src/vdbe.c         | 72 ++++++++++++++++++++++++----------------------
 test/progress.test |  2 +-
 4 files changed, 47 insertions(+), 43 deletions(-)

diff --git a/manifest b/manifest
index 4f18895950..abe4d511cf 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Adjust\sthe\scosts\sin\sthe\sxBestIndex\sfunction\sof\sthe\sspellfix1\svirtual\stable\nto\sforce\sthe\suse\sof\sthe\sMATCH\sterm\sif\sit\sis\savailable.
-D 2013-07-09T15:56:44.605
+C Run\sprogress\scallback\schecks\sless\sfrequently\sin\sthe\smain\sVDBE\sevaluation\nloop.\s\sThis\smakes\sup\sfor\sthe\sextra\sCPU\scycles\sused\sto\sincrement\sthe\scycle\ncounter\sfor\sSQLITE_STMTSTATUS_VM_STEP.
+D 2013-07-10T03:05:14.910
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 5e41da95d92656a5004b03d3576e8b226858a28e
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -277,7 +277,7 @@ F src/update.c 8e76c3d03e4b7b21cb250bd2df0c05e12993e577
 F src/utf.c 8d819e2e5104a430fc2005f018db14347c95a38f
 F src/util.c f566b5138099a2df8533b190d0dcc74b7dfbe0c9
 F src/vacuum.c d9c5759f4c5a438bb43c2086f72c5d2edabc36c8
-F src/vdbe.c 2e3fc618ff964cd559844fdbf186fdc582b66b1e
+F src/vdbe.c b4d29f875ff2c8506783c6831b2d539cdeb39b91
 F src/vdbe.h b52887278cb173e66188da84dfab216bea61119d
 F src/vdbeInt.h aa185c6df4f2b5ec9896cdb5f96789af1ef69f76
 F src/vdbeapi.c e3ad4cddb713a387527f982e79d9e001a0dbffa5
@@ -715,7 +715,7 @@ F test/permutations.test 461ef4ea10db02cd421dfe5f988eac3e99b5cd9a
 F test/pragma.test 5e7de6c32a5d764f09437d2025f07e4917b9e178
 F test/pragma2.test 3a55f82b954242c642f8342b17dffc8b47472947
 F test/printf.test ec9870c4dce8686a37818e0bf1aba6e6a1863552
-F test/progress.test 5b075c3c790c7b2a61419bc199db87aaf48b8301
+F test/progress.test 552dc1edc37333a8d3098b8c26a2b7f06f5799d7
 F test/ptrchng.test ef1aa72d6cf35a2bbd0869a649b744e9d84977fc
 F test/quick.test 1681febc928d686362d50057c642f77a02c62e57
 F test/quota-glob.test 32901e9eed6705d68ca3faee2a06b73b57cb3c26
@@ -1101,7 +1101,7 @@ F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh fbc018d67fd7395f440c28f33ef0f94420226381
 F tool/wherecosttest.c f407dc4c79786982a475261866a161cd007947ae
 F tool/win/sqlite.vsix 97894c2790eda7b5bce3cc79cb2a8ec2fde9b3ac
-P 1e39f85077f1f2b96c3a656c5b6334bafb005908
-R 2ea622f28aaf7cdeeb856cb215ef9fb3
+P f003bea9fe1b79e2b4d18fbef86c1d8f0f60e4b6
+R 04afd42ac3962714b1d32f16a2fdd2ad
 U drh
-Z 80087d9cff19d8b6d80e8c14572ef089
+Z 82045c2120955e8475cc20915ea24bea
diff --git a/manifest.uuid b/manifest.uuid
index 1984d58a78..655deedd5a 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-f003bea9fe1b79e2b4d18fbef86c1d8f0f60e4b6
\ No newline at end of file
+3e8b02011db2f393d4850115a471709b0a88594f
\ No newline at end of file
diff --git a/src/vdbe.c b/src/vdbe.c
index f539b400a9..9a56518c57 100644
--- a/src/vdbe.c
+++ b/src/vdbe.c
@@ -552,12 +552,11 @@ int sqlite3VdbeExec(
   sqlite3 *db = p->db;       /* The database */
   u8 resetSchemaOnFault = 0; /* Reset schema after an error if positive */
   u8 encoding = ENC(db);     /* The database encoding */
-#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
-  int checkProgress;         /* True if progress callbacks are enabled */
-  int nProgressOps = 0;      /* Opcodes executed since progress callback. */
-#endif
   int iCompare = 0;          /* Result of last OP_Compare operation */
   unsigned nVmStep = 0;      /* Number of virtual machine steps */
+#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
+  unsigned nProgressOps = 0; /* nVmStep at last progress callback. */
+#endif
   Mem *aMem = p->aMem;       /* Copy of p->aMem */
   Mem *pIn1 = 0;             /* 1st input operand */
   Mem *pIn2 = 0;             /* 2nd input operand */
@@ -586,9 +585,6 @@ int sqlite3VdbeExec(
   db->busyHandler.nBusy = 0;
   CHECK_FOR_INTERRUPT;
   sqlite3VdbeIOTraceSql(p);
-#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
-  checkProgress = db->xProgress!=0;
-#endif
 #ifdef SQLITE_DEBUG
   sqlite3BeginBenignMalloc();
   if( p->pc==0  && (p->db->flags & SQLITE_VdbeListing)!=0 ){
@@ -636,27 +632,6 @@ int sqlite3VdbeExec(
     }
 #endif
 
-#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
-    /* Call the progress callback if it is configured and the required number
-    ** of VDBE ops have been executed (either since this invocation of
-    ** sqlite3VdbeExec() or since last time the progress callback was called).
-    ** If the progress callback returns non-zero, exit the virtual machine with
-    ** a return code SQLITE_ABORT.
-    */
-    if( checkProgress ){
-      if( db->nProgressOps==nProgressOps ){
-        int prc;
-        prc = db->xProgress(db->pProgressArg);
-        if( prc!=0 ){
-          rc = SQLITE_INTERRUPT;
-          goto vdbe_error_halt;
-        }
-        nProgressOps = 0;
-      }
-      nProgressOps++;
-    }
-#endif
-
     /* On any opcode with the "out2-prerelease" tag, free any
     ** external allocations out of mem[p2] and set mem[p2] to be
     ** an undefined integer.  Opcodes will either fill in the integer
@@ -749,8 +724,38 @@ int sqlite3VdbeExec(
 ** the program.
 */
 case OP_Goto: {             /* jump */
-  CHECK_FOR_INTERRUPT;
   pc = pOp->p2 - 1;
+
+  /* Opcodes that are used as the bottom of a loop (OP_Next, OP_Prev,
+  ** OP_VNext, OP_RowSetNext, or OP_SorterNext) all jump here upon
+  ** completion.  Check to see if sqlite3_interrupt() has been called
+  ** or if the progress callback needs to be invoked. 
+  **
+  ** This code uses unstructured "goto" statements and does not look clean.
+  ** But that is not due to sloppy coding habits. The code is written this
+  ** way for performance, to avoid having to run the interrupt and progress
+  ** checks on every opcode.  This helps sqlite3_step() to run about 1.5%
+  ** faster according to "valgrind --tool=cachegrind" */
+check_for_interrupt:
+  CHECK_FOR_INTERRUPT;
+#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
+  /* Call the progress callback if it is configured and the required number
+  ** of VDBE ops have been executed (either since this invocation of
+  ** sqlite3VdbeExec() or since last time the progress callback was called).
+  ** If the progress callback returns non-zero, exit the virtual machine with
+  ** a return code SQLITE_ABORT.
+  */
+  if( db->xProgress!=0 && (nVmStep - nProgressOps)>=db->nProgressOps ){
+    int prc;
+    prc = db->xProgress(db->pProgressArg);
+    if( prc!=0 ){
+      rc = SQLITE_INTERRUPT;
+      goto vdbe_error_halt;
+    }
+    nProgressOps = nVmStep;
+  }
+#endif
+  
   break;
 }
 
@@ -4502,7 +4507,6 @@ case OP_Next: {        /* jump */
   VdbeCursor *pC;
   int res;
 
-  CHECK_FOR_INTERRUPT;
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
   assert( pOp->p5<=ArraySize(p->aCounter) );
   pC = p->apCsr[pOp->p1];
@@ -4531,7 +4535,7 @@ case OP_Next: {        /* jump */
 #endif
   }
   pC->rowidIsValid = 0;
-  break;
+  goto check_for_interrupt;
 }
 
 /* Opcode: IdxInsert P1 P2 P3 * P5
@@ -5057,7 +5061,7 @@ case OP_RowSetAdd: {       /* in1, in2 */
 */
 case OP_RowSetRead: {       /* jump, in1, out3 */
   i64 val;
-  CHECK_FOR_INTERRUPT;
+
   pIn1 = &aMem[pOp->p1];
   if( (pIn1->flags & MEM_RowSet)==0 
    || sqlite3RowSetNext(pIn1->u.pRowSet, &val)==0
@@ -5069,7 +5073,7 @@ case OP_RowSetRead: {       /* jump, in1, out3 */
     /* A value was pulled from the index */
     sqlite3VdbeMemSetInt64(&aMem[pOp->p3], val);
   }
-  break;
+  goto check_for_interrupt;
 }
 
 /* Opcode: RowSetTest P1 P2 P3 P4
@@ -5970,7 +5974,7 @@ case OP_VNext: {   /* jump */
     /* If there is data, jump to P2 */
     pc = pOp->p2 - 1;
   }
-  break;
+  goto check_for_interrupt;
 }
 #endif /* SQLITE_OMIT_VIRTUALTABLE */
 
diff --git a/test/progress.test b/test/progress.test
index b25a100530..381f4826c8 100644
--- a/test/progress.test
+++ b/test/progress.test
@@ -166,7 +166,7 @@ do_test progress-1.7 {
   set ::res [list]
   db eval {SELECT a, b, c FROM abc} {
     lappend ::res $a $b $c
-    db progress 10 "expr 1"
+    db progress 5 "expr 1"
     catch {db eval {SELECT a, b, c FROM abc} { }} msg
     lappend ::res $msg
   }

From 13447bf6c7c63f247e5765d19086c006a57ebae3 Mon Sep 17 00:00:00 2001
From: drh <drh@noemail.net>
Date: Wed, 10 Jul 2013 13:33:49 +0000
Subject: [PATCH 3/5] Experimental "PRAGMA query_only=BOOLEAN" statement that
 is able to turn write capabilities on and off.

FossilOrigin-Name: ece960c496717a3a6c25526ef77dd76b08d607bc
---
 manifest        | 19 +++++++++++--------
 manifest.uuid   |  2 +-
 src/pragma.c    |  1 +
 src/sqliteInt.h |  1 +
 src/vdbe.c      |  4 ++++
 5 files changed, 18 insertions(+), 9 deletions(-)

diff --git a/manifest b/manifest
index abe4d511cf..024b499450 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Run\sprogress\scallback\schecks\sless\sfrequently\sin\sthe\smain\sVDBE\sevaluation\nloop.\s\sThis\smakes\sup\sfor\sthe\sextra\sCPU\scycles\sused\sto\sincrement\sthe\scycle\ncounter\sfor\sSQLITE_STMTSTATUS_VM_STEP.
-D 2013-07-10T03:05:14.910
+C Experimental\s"PRAGMA\squery_only=BOOLEAN"\sstatement\sthat\sis\sable\sto\sturn\nwrite\scapabilities\son\sand\soff.
+D 2013-07-10T13:33:49.764
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 5e41da95d92656a5004b03d3576e8b226858a28e
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -210,7 +210,7 @@ F src/parse.y 9acfcc83ddbf0cf82f0ed9582ccf0ad6c366ff37
 F src/pcache.c f8043b433a57aba85384a531e3937a804432a346
 F src/pcache.h a5e4f5d9f5d592051d91212c5949517971ae6222
 F src/pcache1.c d23d07716de96c7c0c2503ec5051a4384c3fb938
-F src/pragma.c 67a611bd4be0754f27ee13eb87932c3b14415862
+F src/pragma.c f91b64b84cbc3f3d2a1bbcae0d59e0a782fc67f8
 F src/prepare.c 2306be166bbeddf454e18bf8b21dba8388d05328
 F src/printf.c 41c49dac366a3a411190001a8ab495fa8887974e
 F src/random.c cd4a67b3953b88019f8cd4ccd81394a8ddfaba50
@@ -221,7 +221,7 @@ F src/shell.c c8cd06e6b66250a3ea0149c4edec30de14f57b6f
 F src/sqlite.h.in 0a87152a6dde55381afb8f1cf37f337b2f32fd06
 F src/sqlite3.rc fea433eb0a59f4c9393c8e6d76a6e2596b1fe0c0
 F src/sqlite3ext.h 886f5a34de171002ad46fae8c36a7d8051c190fc
-F src/sqliteInt.h e461e0f9109ca49ad6aba52198fbe7d237c4a75b
+F src/sqliteInt.h 2819a1e48805199a957570223e54e787935937d6
 F src/sqliteLimit.h 164b0e6749d31e0daa1a4589a169d31c0dec7b3d
 F src/status.c bedc37ec1a6bb9399944024d63f4c769971955a9
 F src/table.c 2cd62736f845d82200acfa1287e33feb3c15d62e
@@ -277,7 +277,7 @@ F src/update.c 8e76c3d03e4b7b21cb250bd2df0c05e12993e577
 F src/utf.c 8d819e2e5104a430fc2005f018db14347c95a38f
 F src/util.c f566b5138099a2df8533b190d0dcc74b7dfbe0c9
 F src/vacuum.c d9c5759f4c5a438bb43c2086f72c5d2edabc36c8
-F src/vdbe.c b4d29f875ff2c8506783c6831b2d539cdeb39b91
+F src/vdbe.c c714445b47b4f242082e97de01272f0c31c3c921
 F src/vdbe.h b52887278cb173e66188da84dfab216bea61119d
 F src/vdbeInt.h aa185c6df4f2b5ec9896cdb5f96789af1ef69f76
 F src/vdbeapi.c e3ad4cddb713a387527f982e79d9e001a0dbffa5
@@ -1101,7 +1101,10 @@ F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh fbc018d67fd7395f440c28f33ef0f94420226381
 F tool/wherecosttest.c f407dc4c79786982a475261866a161cd007947ae
 F tool/win/sqlite.vsix 97894c2790eda7b5bce3cc79cb2a8ec2fde9b3ac
-P f003bea9fe1b79e2b4d18fbef86c1d8f0f60e4b6
-R 04afd42ac3962714b1d32f16a2fdd2ad
+P 3e8b02011db2f393d4850115a471709b0a88594f
+R 2ffb7f6b213f90920cd38490a5dc43b1
+T *branch * query_only
+T *sym-query_only *
+T -sym-trunk *
 U drh
-Z 82045c2120955e8475cc20915ea24bea
+Z c3b9d6d6edee565b9fc4629e8b5e8b24
diff --git a/manifest.uuid b/manifest.uuid
index 655deedd5a..3cbb719398 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-3e8b02011db2f393d4850115a471709b0a88594f
\ No newline at end of file
+ece960c496717a3a6c25526ef77dd76b08d607bc
\ No newline at end of file
diff --git a/src/pragma.c b/src/pragma.c
index 5803f6c4a5..f38e679a44 100644
--- a/src/pragma.c
+++ b/src/pragma.c
@@ -177,6 +177,7 @@ static int flagPragma(Parse *pParse, const char *zLeft, const char *zRight){
     { "fullfsync",                SQLITE_FullFSync     },
     { "checkpoint_fullfsync",     SQLITE_CkptFullFSync },
     { "reverse_unordered_selects", SQLITE_ReverseOrder  },
+    { "query_only",               SQLITE_QueryOnly     },
 #ifndef SQLITE_OMIT_AUTOMATIC_INDEX
     { "automatic_index",          SQLITE_AutoIndex     },
 #endif
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 5e3b4d0a0b..48a1f96ea3 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -1009,6 +1009,7 @@ struct sqlite3 {
 #define SQLITE_PreferBuiltin  0x00100000  /* Preference to built-in funcs */
 #define SQLITE_LoadExtension  0x00200000  /* Enable load_extension */
 #define SQLITE_EnableTrigger  0x00400000  /* True to enable triggers */
+#define SQLITE_QueryOnly      0x00800000  /* Disable database changes */
 
 /*
 ** Bits of the sqlite3.dbOptFlags field that are used by the
diff --git a/src/vdbe.c b/src/vdbe.c
index 9a56518c57..1fa21df6d1 100644
--- a/src/vdbe.c
+++ b/src/vdbe.c
@@ -2946,6 +2946,10 @@ case OP_Transaction: {
   assert( p->readOnly==0 || pOp->p2==0 );
   assert( pOp->p1>=0 && pOp->p1<db->nDb );
   assert( (p->btreeMask & (((yDbMask)1)<<pOp->p1))!=0 );
+  if( pOp->p2 && (db->flags & SQLITE_QueryOnly)!=0 ){
+    rc = SQLITE_READONLY;
+    goto abort_due_to_error;
+  }
   pBt = db->aDb[pOp->p1].pBt;
 
   if( pBt ){

From 8f8c65f79bbea1e125fe02042c57cf963288abc5 Mon Sep 17 00:00:00 2001
From: drh <drh@noemail.net>
Date: Wed, 10 Jul 2013 18:14:29 +0000
Subject: [PATCH 4/5] Fix harmless compiler warnings in the progress callback
 logic.

FossilOrigin-Name: 908141d5bf7a9ad8f40c2332476847733eca7fdc
---
 manifest        | 14 +++++++-------
 manifest.uuid   |  2 +-
 src/main.c      |  2 +-
 src/sqliteInt.h |  2 +-
 4 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/manifest b/manifest
index abe4d511cf..817d63dd60 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Run\sprogress\scallback\schecks\sless\sfrequently\sin\sthe\smain\sVDBE\sevaluation\nloop.\s\sThis\smakes\sup\sfor\sthe\sextra\sCPU\scycles\sused\sto\sincrement\sthe\scycle\ncounter\sfor\sSQLITE_STMTSTATUS_VM_STEP.
-D 2013-07-10T03:05:14.910
+C Fix\sharmless\scompiler\swarnings\sin\sthe\sprogress\scallback\slogic.
+D 2013-07-10T18:14:29.988
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 5e41da95d92656a5004b03d3576e8b226858a28e
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -185,7 +185,7 @@ F src/journal.c b4124532212b6952f42eb2c12fa3c25701d8ba8d
 F src/legacy.c 0df0b1550b9cc1f58229644735e317ac89131f12
 F src/lempar.c cdf0a000315332fc9b50b62f3b5e22e080a0952b
 F src/loadext.c c48f7f3f170e502fe0cc20748e03c6e0b5a016c2
-F src/main.c a1f4bb79e15c3f0a2e4efb2f52781ccbfb3010d4
+F src/main.c 97b8ebbab272ab0d97966c791956dad1921357ba
 F src/malloc.c fe085aa851b666b7c375c1ff957643dc20a04bf6
 F src/mem0.c 6a55ebe57c46ca1a7d98da93aaa07f99f1059645
 F src/mem1.c 437c7c4af964895d4650f29881df63535caaa1fa
@@ -221,7 +221,7 @@ F src/shell.c c8cd06e6b66250a3ea0149c4edec30de14f57b6f
 F src/sqlite.h.in 0a87152a6dde55381afb8f1cf37f337b2f32fd06
 F src/sqlite3.rc fea433eb0a59f4c9393c8e6d76a6e2596b1fe0c0
 F src/sqlite3ext.h 886f5a34de171002ad46fae8c36a7d8051c190fc
-F src/sqliteInt.h e461e0f9109ca49ad6aba52198fbe7d237c4a75b
+F src/sqliteInt.h df1a921448e765227de3ed8933fcc1e22bebec82
 F src/sqliteLimit.h 164b0e6749d31e0daa1a4589a169d31c0dec7b3d
 F src/status.c bedc37ec1a6bb9399944024d63f4c769971955a9
 F src/table.c 2cd62736f845d82200acfa1287e33feb3c15d62e
@@ -1101,7 +1101,7 @@ F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh fbc018d67fd7395f440c28f33ef0f94420226381
 F tool/wherecosttest.c f407dc4c79786982a475261866a161cd007947ae
 F tool/win/sqlite.vsix 97894c2790eda7b5bce3cc79cb2a8ec2fde9b3ac
-P f003bea9fe1b79e2b4d18fbef86c1d8f0f60e4b6
-R 04afd42ac3962714b1d32f16a2fdd2ad
+P 3e8b02011db2f393d4850115a471709b0a88594f
+R e1fccaff7bc35266cc5b7f175242cdcd
 U drh
-Z 82045c2120955e8475cc20915ea24bea
+Z 1564bfae3de8c8d60d1d15cc4d698c7c
diff --git a/manifest.uuid b/manifest.uuid
index 655deedd5a..193a2a3d04 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-3e8b02011db2f393d4850115a471709b0a88594f
\ No newline at end of file
+908141d5bf7a9ad8f40c2332476847733eca7fdc
\ No newline at end of file
diff --git a/src/main.c b/src/main.c
index 12a1ad19b6..fe30d43f2c 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1298,7 +1298,7 @@ void sqlite3_progress_handler(
   sqlite3_mutex_enter(db->mutex);
   if( nOps>0 ){
     db->xProgress = xProgress;
-    db->nProgressOps = nOps;
+    db->nProgressOps = (unsigned)nOps;
     db->pProgressArg = pArg;
   }else{
     db->xProgress = 0;
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 5e3b4d0a0b..d1d73cd5bb 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -936,7 +936,7 @@ struct sqlite3 {
 #ifndef SQLITE_OMIT_PROGRESS_CALLBACK
   int (*xProgress)(void *);     /* The progress callback */
   void *pProgressArg;           /* Argument to the progress callback */
-  int nProgressOps;             /* Number of opcodes for progress callback */
+  unsigned nProgressOps;        /* Number of opcodes for progress callback */
 #endif
 #ifndef SQLITE_OMIT_VIRTUALTABLE
   int nVTrans;                  /* Allocated size of aVTrans */

From 648e264342fe3315d23979c8779a4200babea891 Mon Sep 17 00:00:00 2001
From: drh <drh@noemail.net>
Date: Thu, 11 Jul 2013 15:03:32 +0000
Subject: [PATCH 5/5] Add the "defer_foreign_keys" pragma and the
 SQLITE_DBSTATUS_DEFERRED_FKS value for sqlite3_db_status().  This is a
 cherry-pick of a sequence of five checkins in the sessions branch between
 [1d44e5d3c2] and [d39e65fe70].

FossilOrigin-Name: 527121ac3cdc96ac33ad975c227a6685a2f7e999
---
 manifest          |  35 ++++++++--------
 manifest.uuid     |   2 +-
 src/fkey.c        |   9 +++-
 src/main.c        |   2 +
 src/pragma.c      |   6 ++-
 src/sqlite.h.in   |   9 +++-
 src/sqliteInt.h   |   3 ++
 src/status.c      |  10 +++++
 src/test_malloc.c |   3 +-
 src/vdbe.c        |  13 ++++--
 src/vdbeInt.h     |   1 +
 src/vdbeapi.c     |   4 +-
 src/vdbeaux.c     |   7 +++-
 test/fkey1.test   |   3 ++
 test/fkey6.test   | 103 ++++++++++++++++++++++++++++++++++++++++++++++
 15 files changed, 180 insertions(+), 30 deletions(-)
 create mode 100644 test/fkey6.test

diff --git a/manifest b/manifest
index 817d63dd60..e85691eaa3 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Fix\sharmless\scompiler\swarnings\sin\sthe\sprogress\scallback\slogic.
-D 2013-07-10T18:14:29.988
+C Add\sthe\s"defer_foreign_keys"\spragma\sand\sthe\sSQLITE_DBSTATUS_DEFERRED_FKS\nvalue\sfor\ssqlite3_db_status().\s\sThis\sis\sa\scherry-pick\sof\sa\ssequence\sof\sfive\ncheckins\sin\sthe\ssessions\sbranch\sbetween\s[1d44e5d3c2]\sand\s[d39e65fe70].
+D 2013-07-11T15:03:32.117
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 5e41da95d92656a5004b03d3576e8b226858a28e
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -174,7 +174,7 @@ F src/date.c 067a81c9942c497aafd2c260e13add8a7d0c7dd4
 F src/delete.c aeabdabeeeaa0584127f291baa9617153d334778
 F src/expr.c 2b47ae9da6c9f34eff6736962ea2e102c6c4a755
 F src/fault.c 160a0c015b6c2629d3899ed2daf63d75754a32bb
-F src/fkey.c e16942bd5c8a868ac53287886464a5ed0e72b179
+F src/fkey.c 914a6bbd987d857c41ac9d244efa6641f36faadb
 F src/func.c 5c50c1ea31fd864b0fe921fe1a8d4c55acd609ef
 F src/global.c 5caf4deab621abb45b4c607aad1bd21c20aac759
 F src/hash.c ac3470bbf1ca4ae4e306a8ecb0fdf1731810ffe4
@@ -185,7 +185,7 @@ F src/journal.c b4124532212b6952f42eb2c12fa3c25701d8ba8d
 F src/legacy.c 0df0b1550b9cc1f58229644735e317ac89131f12
 F src/lempar.c cdf0a000315332fc9b50b62f3b5e22e080a0952b
 F src/loadext.c c48f7f3f170e502fe0cc20748e03c6e0b5a016c2
-F src/main.c 97b8ebbab272ab0d97966c791956dad1921357ba
+F src/main.c e5810b2d7a0bd19f3d75ce60e3ed918cafc0a3f3
 F src/malloc.c fe085aa851b666b7c375c1ff957643dc20a04bf6
 F src/mem0.c 6a55ebe57c46ca1a7d98da93aaa07f99f1059645
 F src/mem1.c 437c7c4af964895d4650f29881df63535caaa1fa
@@ -210,7 +210,7 @@ F src/parse.y 9acfcc83ddbf0cf82f0ed9582ccf0ad6c366ff37
 F src/pcache.c f8043b433a57aba85384a531e3937a804432a346
 F src/pcache.h a5e4f5d9f5d592051d91212c5949517971ae6222
 F src/pcache1.c d23d07716de96c7c0c2503ec5051a4384c3fb938
-F src/pragma.c 67a611bd4be0754f27ee13eb87932c3b14415862
+F src/pragma.c c87581d93a7518cba656b7919e32ded5d331b76a
 F src/prepare.c 2306be166bbeddf454e18bf8b21dba8388d05328
 F src/printf.c 41c49dac366a3a411190001a8ab495fa8887974e
 F src/random.c cd4a67b3953b88019f8cd4ccd81394a8ddfaba50
@@ -218,12 +218,12 @@ F src/resolve.c 89f9003e8316ee3a172795459efc2a0274e1d5a8
 F src/rowset.c 64655f1a627c9c212d9ab497899e7424a34222e0
 F src/select.c 91b62654caf8dfe292fb8882715e575d34ad3874
 F src/shell.c c8cd06e6b66250a3ea0149c4edec30de14f57b6f
-F src/sqlite.h.in 0a87152a6dde55381afb8f1cf37f337b2f32fd06
+F src/sqlite.h.in 80d11140d401f366f7249f3c4fe031c49a5a06f8
 F src/sqlite3.rc fea433eb0a59f4c9393c8e6d76a6e2596b1fe0c0
 F src/sqlite3ext.h 886f5a34de171002ad46fae8c36a7d8051c190fc
-F src/sqliteInt.h df1a921448e765227de3ed8933fcc1e22bebec82
+F src/sqliteInt.h 074f5cdfb99e0d4dc8100c217824f384c16af56b
 F src/sqliteLimit.h 164b0e6749d31e0daa1a4589a169d31c0dec7b3d
-F src/status.c bedc37ec1a6bb9399944024d63f4c769971955a9
+F src/status.c 7ac05a5c7017d0b9f0b4bcd701228b784f987158
 F src/table.c 2cd62736f845d82200acfa1287e33feb3c15d62e
 F src/tclsqlite.c b8835978e853a89bf58de88acc943a5ca94d752e
 F src/test1.c 870fc648a48cb6d6808393174f7ebe82b8c840fa
@@ -250,7 +250,7 @@ F src/test_intarray.c 87847c71c3c36889c0bcc9c4baf9d31881665d61
 F src/test_intarray.h b999bb18d090b8d9d9c49d36ec37ef8f341fe169
 F src/test_journal.c f5c0a05b7b3d5930db769b5ee6c3766dc2221a64
 F src/test_loadext.c df586c27176e3c2cb2e099c78da67bf14379a56e
-F src/test_malloc.c 2855429b8232107b3296409be2a8eb68345290c2
+F src/test_malloc.c a105801222c0514f8befa2a1712a95505cce099a
 F src/test_multiplex.c 5d691eeb6cb6aa7888da28eba5e62a9a857d3c0f
 F src/test_multiplex.h 9b63b95f07acedee425fdfe49a47197c9bf5f9d8
 F src/test_mutex.c 293042d623ebba969160f471a82aa1551626454f
@@ -277,11 +277,11 @@ F src/update.c 8e76c3d03e4b7b21cb250bd2df0c05e12993e577
 F src/utf.c 8d819e2e5104a430fc2005f018db14347c95a38f
 F src/util.c f566b5138099a2df8533b190d0dcc74b7dfbe0c9
 F src/vacuum.c d9c5759f4c5a438bb43c2086f72c5d2edabc36c8
-F src/vdbe.c b4d29f875ff2c8506783c6831b2d539cdeb39b91
+F src/vdbe.c 0661945edc8b8d85dccc137925c45542fad9a5a4
 F src/vdbe.h b52887278cb173e66188da84dfab216bea61119d
-F src/vdbeInt.h aa185c6df4f2b5ec9896cdb5f96789af1ef69f76
-F src/vdbeapi.c e3ad4cddb713a387527f982e79d9e001a0dbffa5
-F src/vdbeaux.c 9683f262c7fd0af8cb03f0053651135005cdda8a
+F src/vdbeInt.h 5e666c971c555c7977714b0e34cb8d4b20282557
+F src/vdbeapi.c c88222946d657984bdaf394604cb58ed1d641460
+F src/vdbeaux.c 1633408f6dea06129441c5e2f22b2a5ce30fe97e
 F src/vdbeblob.c 5dc79627775bd9a9b494dd956e26297946417d69
 F src/vdbemem.c 833005f1cbbf447289f1973dba2a0c2228c7b8ab
 F src/vdbesort.c 3937e06b2a0e354500e17dc206ef4c35770a5017
@@ -452,11 +452,12 @@ F test/expr.test 67c9fd6f8f829e239dc8b0f4a08a73c08b09196d
 F test/fallocate.test 3e979af17dfa7e5e9dda5eba1a696c04fa9d47f7
 F test/filectrl.test 14fa712e42c4cb791e09dfd58a6a03efb47ef13a
 F test/filefmt.test cb34663f126cbc2d358af552dcaf5c72769b0146
-F test/fkey1.test 01c7de578e11747e720c2d9aeef27f239853c4da
+F test/fkey1.test e1d1fa84cde579185ea01358436839703e415a5b
 F test/fkey2.test 06e0b4cc9e1b3271ae2ae6feeb19755468432111
 F test/fkey3.test 5ec899d12b13bcf1e9ef40eff7fb692fdb91392e
 F test/fkey4.test 86446017011273aad8f9a99c1a65019e7bd9ca9d
 F test/fkey5.test 0bf64f2d19ad80433ca0b24edbf604a18b353d5f
+F test/fkey6.test 2d76497c54db0e5bfbecee0acf00bb8a706b37db
 F test/fkey_malloc.test bb74c9cb8f8fceed03b58f8a7ef2df98520bbd51
 F test/format4.test 1f0cac8ff3895e9359ed87e41aaabee982a812eb
 F test/fts-9fd058691.test 78b887e30ae6816df0e1fed6259de4b5a64ad33c
@@ -1101,7 +1102,7 @@ F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh fbc018d67fd7395f440c28f33ef0f94420226381
 F tool/wherecosttest.c f407dc4c79786982a475261866a161cd007947ae
 F tool/win/sqlite.vsix 97894c2790eda7b5bce3cc79cb2a8ec2fde9b3ac
-P 3e8b02011db2f393d4850115a471709b0a88594f
-R e1fccaff7bc35266cc5b7f175242cdcd
+P 908141d5bf7a9ad8f40c2332476847733eca7fdc
+R f701d887eba2f81d7816617ba86ca3a2
 U drh
-Z 1564bfae3de8c8d60d1d15cc4d698c7c
+Z 50e77e8dbcbbcc008f0da119505e5900
diff --git a/manifest.uuid b/manifest.uuid
index 193a2a3d04..698be2beaf 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-908141d5bf7a9ad8f40c2332476847733eca7fdc
\ No newline at end of file
+527121ac3cdc96ac33ad975c227a6685a2f7e999
\ No newline at end of file
diff --git a/src/fkey.c b/src/fkey.c
index ac35bc194c..bb59c656f6 100644
--- a/src/fkey.c
+++ b/src/fkey.c
@@ -422,7 +422,10 @@ static void fkLookupParent(
     }
   }
 
-  if( !pFKey->isDeferred && !pParse->pToplevel && !pParse->isMultiWrite ){
+  if( !pFKey->isDeferred && !(pParse->db->flags & SQLITE_DeferFKs)
+   && !pParse->pToplevel 
+   && !pParse->isMultiWrite 
+  ){
     /* Special case: If this is an INSERT statement that will insert exactly
     ** one row into the table, raise a constraint immediately instead of
     ** incrementing a counter. This is necessary as the VM code is being
@@ -813,7 +816,9 @@ void sqlite3FkCheck(
     SrcList *pSrc;
     int *aiCol = 0;
 
-    if( !pFKey->isDeferred && !pParse->pToplevel && !pParse->isMultiWrite ){
+    if( !pFKey->isDeferred && !(db->flags & SQLITE_DeferFKs) 
+     && !pParse->pToplevel && !pParse->isMultiWrite 
+    ){
       assert( regOld==0 && regNew!=0 );
       /* Inserting a single row into a parent table cannot cause an immediate
       ** foreign key violation. So do nothing in this case.  */
diff --git a/src/main.c b/src/main.c
index fe30d43f2c..c23a6212d3 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1037,6 +1037,8 @@ void sqlite3RollbackAll(sqlite3 *db, int tripCode){
 
   /* Any deferred constraint violations have now been resolved. */
   db->nDeferredCons = 0;
+  db->nDeferredImmCons = 0;
+  db->flags &= ~SQLITE_DeferFKs;
 
   /* If one has been configured, invoke the rollback-hook callback */
   if( db->xRollbackCallback && (inTrans || !db->autoCommit) ){
diff --git a/src/pragma.c b/src/pragma.c
index 5803f6c4a5..fd0ebc727c 100644
--- a/src/pragma.c
+++ b/src/pragma.c
@@ -197,12 +197,13 @@ static int flagPragma(Parse *pParse, const char *zLeft, const char *zRight){
     /* TODO: Maybe it shouldn't be possible to change the ReadUncommitted
     ** flag if there are any active statements. */
     { "read_uncommitted",         SQLITE_ReadUncommitted },
-    { "recursive_triggers",       SQLITE_RecTriggers },
+    { "recursive_triggers",       SQLITE_RecTriggers   },
 
     /* This flag may only be set if both foreign-key and trigger support
     ** are present in the build.  */
 #if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
-    { "foreign_keys",             SQLITE_ForeignKeys },
+    { "foreign_keys",             SQLITE_ForeignKeys   },
+    { "defer_foreign_keys",       SQLITE_DeferFKs      },
 #endif
   };
   int i;
@@ -228,6 +229,7 @@ static int flagPragma(Parse *pParse, const char *zLeft, const char *zRight){
             db->flags |= mask;
           }else{
             db->flags &= ~mask;
+            if( mask==SQLITE_DeferFKs ) db->nDeferredImmCons = 0;
           }
 
           /* Many of the flag-pragmas modify the code generated by the SQL 
diff --git a/src/sqlite.h.in b/src/sqlite.h.in
index 87bce973a4..4d8ba21f30 100644
--- a/src/sqlite.h.in
+++ b/src/sqlite.h.in
@@ -6239,6 +6239,12 @@ int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
 ** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The
 ** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0.
 ** </dd>
+**
+** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(<dt>SQLITE_DBSTATUS_DEFERRED_FKS</dt>
+** <dd>This parameter returns the zero for the current value if and only if
+** there all foreign key constraints (deferred or immediate) have been
+** resolved.  The highwater mark is always 0.
+** </dd>
 ** </dl>
 */
 #define SQLITE_DBSTATUS_LOOKASIDE_USED       0
@@ -6251,7 +6257,8 @@ int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
 #define SQLITE_DBSTATUS_CACHE_HIT            7
 #define SQLITE_DBSTATUS_CACHE_MISS           8
 #define SQLITE_DBSTATUS_CACHE_WRITE          9
-#define SQLITE_DBSTATUS_MAX                  9   /* Largest defined DBSTATUS */
+#define SQLITE_DBSTATUS_DEFERRED_FKS        10
+#define SQLITE_DBSTATUS_MAX                 10   /* Largest defined DBSTATUS */
 
 
 /*
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index d1d73cd5bb..dcd74f91d2 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -954,6 +954,7 @@ struct sqlite3 {
   int nSavepoint;               /* Number of non-transaction savepoints */
   int nStatement;               /* Number of nested statement-transactions  */
   i64 nDeferredCons;            /* Net deferred constraints this transaction. */
+  i64 nDeferredImmCons;         /* Net deferred immediate constraints */
   int *pnBytesFreed;            /* If not NULL, increment this in DbFree() */
 
 #ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
@@ -1009,6 +1010,7 @@ struct sqlite3 {
 #define SQLITE_PreferBuiltin  0x00100000  /* Preference to built-in funcs */
 #define SQLITE_LoadExtension  0x00200000  /* Enable load_extension */
 #define SQLITE_EnableTrigger  0x00400000  /* True to enable triggers */
+#define SQLITE_DeferFKs       0x00800000  /* Defer all FK constraints */
 
 /*
 ** Bits of the sqlite3.dbOptFlags field that are used by the
@@ -1155,6 +1157,7 @@ struct FuncDestructor {
 struct Savepoint {
   char *zName;                        /* Savepoint name (nul-terminated) */
   i64 nDeferredCons;                  /* Number of deferred fk violations */
+  i64 nDeferredImmCons;               /* Number of deferred imm fk. */
   Savepoint *pNext;                   /* Parent savepoint (if any) */
 };
 
diff --git a/src/status.c b/src/status.c
index 28349e6d3d..5fcb68ddc3 100644
--- a/src/status.c
+++ b/src/status.c
@@ -243,6 +243,16 @@ int sqlite3_db_status(
       break;
     }
 
+    /* Set *pCurrent to non-zero if there are unresolved deferred foreign
+    ** key constraints.  Set *pCurrent to zero if all foreign key constraints
+    ** have been satisfied.  The *pHighwater is always set to zero.
+    */
+    case SQLITE_DBSTATUS_DEFERRED_FKS: {
+      *pHighwater = 0;
+      *pCurrent = db->nDeferredImmCons>0 || db->nDeferredCons>0;
+      break;
+    }
+
     default: {
       rc = SQLITE_ERROR;
     }
diff --git a/src/test_malloc.c b/src/test_malloc.c
index cf98a8fb21..2e31f0833d 100644
--- a/src/test_malloc.c
+++ b/src/test_malloc.c
@@ -1349,7 +1349,8 @@ static int test_db_status(
     { "LOOKASIDE_MISS_FULL", SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL },
     { "CACHE_HIT",           SQLITE_DBSTATUS_CACHE_HIT           },
     { "CACHE_MISS",          SQLITE_DBSTATUS_CACHE_MISS          },
-    { "CACHE_WRITE",         SQLITE_DBSTATUS_CACHE_WRITE         }
+    { "CACHE_WRITE",         SQLITE_DBSTATUS_CACHE_WRITE         },
+    { "DEFERRED_FKS",        SQLITE_DBSTATUS_DEFERRED_FKS        }
   };
   Tcl_Obj *pResult;
   if( objc!=4 ){
diff --git a/src/vdbe.c b/src/vdbe.c
index 9a56518c57..104ea8b702 100644
--- a/src/vdbe.c
+++ b/src/vdbe.c
@@ -874,7 +874,7 @@ case OP_Halt: {
     p->rc = rc = SQLITE_BUSY;
   }else{
     assert( rc==SQLITE_OK || (p->rc&0xff)==SQLITE_CONSTRAINT );
-    assert( rc==SQLITE_OK || db->nDeferredCons>0 );
+    assert( rc==SQLITE_OK || db->nDeferredCons>0 || db->nDeferredImmCons>0 );
     rc = p->rc ? SQLITE_ERROR : SQLITE_DONE;
   }
   goto vdbe_return;
@@ -2734,6 +2734,7 @@ case OP_Savepoint: {
         pNew->pNext = db->pSavepoint;
         db->pSavepoint = pNew;
         pNew->nDeferredCons = db->nDeferredCons;
+        pNew->nDeferredImmCons = db->nDeferredImmCons;
       }
     }
   }else{
@@ -2821,6 +2822,7 @@ case OP_Savepoint: {
         }
       }else{
         db->nDeferredCons = pSavepoint->nDeferredCons;
+        db->nDeferredImmCons = pSavepoint->nDeferredImmCons;
       }
 
       if( !isTransaction ){
@@ -2978,6 +2980,7 @@ case OP_Transaction: {
       ** counter. If the statement transaction needs to be rolled back,
       ** the value of this counter needs to be restored too.  */
       p->nStmtDefCons = db->nDeferredCons;
+      p->nStmtDefImmCons = db->nDeferredImmCons;
     }
   }
   break;
@@ -5287,7 +5290,9 @@ case OP_Param: {           /* out2-prerelease */
 ** statement counter is incremented (immediate foreign key constraints).
 */
 case OP_FkCounter: {
-  if( pOp->p1 ){
+  if( db->flags & SQLITE_DeferFKs ){
+    db->nDeferredImmCons += pOp->p2;
+  }else if( pOp->p1 ){
     db->nDeferredCons += pOp->p2;
   }else{
     p->nFkConstraint += pOp->p2;
@@ -5308,9 +5313,9 @@ case OP_FkCounter: {
 */
 case OP_FkIfZero: {         /* jump */
   if( pOp->p1 ){
-    if( db->nDeferredCons==0 ) pc = pOp->p2-1;
+    if( db->nDeferredCons==0 && db->nDeferredImmCons==0 ) pc = pOp->p2-1;
   }else{
-    if( p->nFkConstraint==0 ) pc = pOp->p2-1;
+    if( p->nFkConstraint==0 && db->nDeferredImmCons==0 ) pc = pOp->p2-1;
   }
   break;
 }
diff --git a/src/vdbeInt.h b/src/vdbeInt.h
index 289f83d45d..11c34fd524 100644
--- a/src/vdbeInt.h
+++ b/src/vdbeInt.h
@@ -351,6 +351,7 @@ struct Vdbe {
 #endif
   i64 nFkConstraint;      /* Number of imm. FK constraints this VM */
   i64 nStmtDefCons;       /* Number of def. constraints when stmt started */
+  i64 nStmtDefImmCons;    /* Number of def. imm constraints when stmt started */
   char *zSql;             /* Text of the SQL statement that generated this */
   void *pFree;            /* Free this when deleting the vdbe */
 #ifdef SQLITE_DEBUG
diff --git a/src/vdbeapi.c b/src/vdbeapi.c
index efa9e96962..ad3eea13a7 100644
--- a/src/vdbeapi.c
+++ b/src/vdbeapi.c
@@ -386,7 +386,9 @@ static int sqlite3Step(Vdbe *p){
       db->u1.isInterrupted = 0;
     }
 
-    assert( db->nVdbeWrite>0 || db->autoCommit==0 || db->nDeferredCons==0 );
+    assert( db->nVdbeWrite>0 || db->autoCommit==0 
+        || (db->nDeferredCons==0 && db->nDeferredImmCons==0)
+    );
 
 #ifndef SQLITE_OMIT_TRACE
     if( db->xProfile && !db->init.busy ){
diff --git a/src/vdbeaux.c b/src/vdbeaux.c
index fb8294a256..dfdf7800a4 100644
--- a/src/vdbeaux.c
+++ b/src/vdbeaux.c
@@ -2065,6 +2065,7 @@ int sqlite3VdbeCloseStatement(Vdbe *p, int eOp){
     ** the statement transaction was opened.  */
     if( eOp==SAVEPOINT_ROLLBACK ){
       db->nDeferredCons = p->nStmtDefCons;
+      db->nDeferredImmCons = p->nStmtDefImmCons;
     }
   }
   return rc;
@@ -2083,7 +2084,9 @@ int sqlite3VdbeCloseStatement(Vdbe *p, int eOp){
 #ifndef SQLITE_OMIT_FOREIGN_KEY
 int sqlite3VdbeCheckFk(Vdbe *p, int deferred){
   sqlite3 *db = p->db;
-  if( (deferred && db->nDeferredCons>0) || (!deferred && p->nFkConstraint>0) ){
+  if( (deferred && (db->nDeferredCons+db->nDeferredImmCons)>0) 
+   || (!deferred && p->nFkConstraint>0) 
+  ){
     p->rc = SQLITE_CONSTRAINT_FOREIGNKEY;
     p->errorAction = OE_Abort;
     sqlite3SetString(&p->zErrMsg, db, "foreign key constraint failed");
@@ -2216,6 +2219,8 @@ int sqlite3VdbeHalt(Vdbe *p){
           sqlite3RollbackAll(db, SQLITE_OK);
         }else{
           db->nDeferredCons = 0;
+          db->nDeferredImmCons = 0;
+          db->flags &= ~SQLITE_DeferFKs;
           sqlite3CommitInternalChanges(db);
         }
       }else{
diff --git a/test/fkey1.test b/test/fkey1.test
index e7c00d16d4..90a4c44409 100644
--- a/test/fkey1.test
+++ b/test/fkey1.test
@@ -117,5 +117,8 @@ do_test fkey1-3.4 {
   {0 0 t5 d {} {SET DEFAULT} CASCADE NONE} \
   {0 1 t5 e {} {SET DEFAULT} CASCADE NONE} \
 ]
+do_test fkey1-3.5 {
+  sqlite3_db_status db DBSTATUS_DEFERRED_FKS 0
+} {0 0 0}
 
 finish_test
diff --git a/test/fkey6.test b/test/fkey6.test
new file mode 100644
index 0000000000..66286b43ec
--- /dev/null
+++ b/test/fkey6.test
@@ -0,0 +1,103 @@
+# 2012 December 17
+#
+# 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.
+#
+# This file tests the PRAGMA defer_foreign_keys and 
+# SQLITE_DBSTATUS_DEFERRED_FKS
+#
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+
+ifcapable {!foreignkey} {
+  finish_test
+  return
+}
+
+do_execsql_test fkey6-1.1 {
+  PRAGMA foreign_keys=ON;
+  CREATE TABLE t1(x INTEGER PRIMARY KEY);
+  CREATE TABLE t2(y INTEGER PRIMARY KEY,
+          z INTEGER REFERENCES t1(x) DEFERRABLE INITIALLY DEFERRED);
+  CREATE INDEX t2z ON t2(z);
+  CREATE TABLE t3(u INTEGER PRIMARY KEY, v INTEGER REFERENCES t1(x));
+  CREATE INDEX t3v ON t3(v);
+  INSERT INTO t1 VALUES(1),(2),(3),(4),(5);
+  INSERT INTO t2 VALUES(1,1),(2,2);
+  INSERT INTO t3 VALUES(3,3),(4,4);
+} {}
+do_test fkey6-1.2 {
+  catchsql {DELETE FROM t1 WHERE x=2;}
+} {1 {foreign key constraint failed}}
+do_test fkey6-1.3 {
+  sqlite3_db_status db DBSTATUS_DEFERRED_FKS 0
+} {0 0 0}
+do_test fkey6-1.4 {
+  execsql {
+    BEGIN;
+    DELETE FROM t1 WHERE x=1;
+  }
+} {}
+do_test fkey6-1.5.1 {
+  sqlite3_db_status db DBSTATUS_DEFERRED_FKS 1
+} {0 1 0}
+do_test fkey6-1.5.2 {
+  sqlite3_db_status db DBSTATUS_DEFERRED_FKS 0
+} {0 1 0}
+do_test fkey6-1.6 {
+  execsql {
+    ROLLBACK;
+  }
+} {}
+do_test fkey6-1.7 {
+  sqlite3_db_status db DBSTATUS_DEFERRED_FKS 0
+} {0 0 0}
+do_test fkey6-1.8 {
+  execsql {
+    PRAGMA defer_foreign_keys=ON;
+    BEGIN;
+    DELETE FROM t1 WHERE x=3;
+  }
+} {}
+do_test fkey6-1.9 {
+  sqlite3_db_status db DBSTATUS_DEFERRED_FKS 0
+} {0 1 0}
+do_test fkey6-1.10 {
+  execsql {
+    ROLLBACK;
+    PRAGMA defer_foreign_keys=OFF;
+    BEGIN;
+  }
+  catchsql {DELETE FROM t1 WHERE x=3}
+} {1 {foreign key constraint failed}}
+db eval {ROLLBACK}
+
+do_test fkey6-1.20 {
+  execsql {
+    BEGIN;
+    DELETE FROM t1 WHERE x=1;
+  }
+  sqlite3_db_status db DBSTATUS_DEFERRED_FKS 0
+} {0 1 0}
+do_test fkey6-1.21 {
+  execsql {
+    DELETE FROM t2 WHERE y=1;
+  }
+  sqlite3_db_status db DBSTATUS_DEFERRED_FKS 0
+} {0 0 0}
+do_test fkey6-1.22 {
+  execsql {
+    COMMIT;
+  }
+} {}
+
+
+finish_test