Begin a series of changes designed to reduce the scope and frequency of

invalidating schemas.  Design goals are that the internal schema should
never be deleted out from under a prepared statement that is running and
that all prepared statements should be expired if the schema is invalidated.
At the same time, minimize the number of schema invalidations.  This change
merely revises the sqlite3ResetInternalSchema() function to use -1 as the
wildcard for "all" rather than 0, so that we can reset the main schema
independently of all the others.

FossilOrigin-Name: 6a8ad6e31e0d2b8a5ace38faf0efd805155ee5f3

diff --git a/manifest b/manifest
index 8411b2239fcc8f8ca08825ba0b11abac8ff2ca49..2df976638088053f82e06c8745d4253872e1ec86 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Fix\sa\srace\scondition\sin\sOP_ParseSchema.
-D 2011-04-02T09:44:43
+C Begin\sa\sseries\sof\schanges\sdesigned\sto\sreduce\sthe\sscope\sand\sfrequency\sof\ninvalidating\sschemas.\s\sDesign\sgoals\sare\sthat\sthe\sinternal\sschema\sshould\nnever\sbe\sdeleted\sout\sfrom\sunder\sa\sprepared\sstatement\sthat\sis\srunning\sand\nthat\sall\sprepared\sstatements\sshould\sbe\sexpired\sif\sthe\sschema\sis\sinvalidated.\nAt\sthe\ssame\stime,\sminimize\sthe\snumber\sof\sschema\sinvalidations.\s\sThis\schange\nmerely\srevises\sthe\ssqlite3ResetInternalSchema()\sfunction\sto\suse\s-1\sas\sthe\nwildcard\sfor\s"all"\srather\sthan\s0,\sso\sthat\swe\scan\sreset\sthe\smain\sschema\nindependently\sof\sall\sthe\sothers.
+D 2011-04-02T16:28:52.034
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 7a4d9524721d40ef9ee26f93f9bd6a51dba106f2
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -116,15 +116,15 @@ F sqlite3.1 6be1ad09113570e1fc8dcaff84c9b0b337db5ffc
 F sqlite3.pc.in ae6f59a76e862f5c561eb32a380228a02afc3cad
 F src/alter.c 280f5c04b11b492703a342222b3de0a999445280
 F src/analyze.c d0a673d303f611690fc7a3293aaefed57cccc5c8
-F src/attach.c 438ea6f6b5d5961c1f49b737f2ce0f14ce7c6877
+F src/attach.c 7cae2cf0c14762ce14c074a860ec52890a973a56
 F src/auth.c 523da7fb4979469955d822ff9298352d6b31de34
-F src/backup.c 537f89c7ef5021cb580f31f782e556ffffcb2ed1
+F src/backup.c b7529a6691f0fd534ae8ff622203c46a7f1b626b
 F src/bitvec.c af50f1c8c0ff54d6bdb7a80e2fceca5a93670bef
 F src/btmutex.c 96a12f50f7a17475155971a241d85ec5171573ff
 F src/btree.c 2b9c81ff64da339a67dda4f94c0d763627be0b67
 F src/btree.h 8d36f774ec4b1d0027b8966f8c03d9a72a518c14
 F src/btreeInt.h 20f73dc93b1eeb83afd7259fbc6bd7dcf2df7fe4
-F src/build.c 6c490fe14dedb094a202f559e3b29a276abffcf8
+F src/build.c 9dca3dc000b85753cff822c69151f88d913f3b3e
 F src/callback.c 5069f224882cbdccd559f591271d28d7f37745bc
 F src/complete.c dc1d136c0feee03c2f7550bafc0d29075e36deac
 F src/ctime.c 52ff72f966cee3087e0138a3ec69371c22be3c01
@@ -143,7 +143,7 @@ F src/journal.c 552839e54d1bf76fb8f7abe51868b66acacf6a0e
 F src/legacy.c a199d7683d60cef73089e892409113e69c23a99f
 F src/lempar.c 7f026423f4d71d989e719a743f98a1cbd4e6d99e
 F src/loadext.c 8af9fcc75708d60b88636ccba38b4a7b3c155c3e
-F src/main.c c23c62e53d120c5eee086c0e2cc96cc9a691c50e
+F src/main.c 14c019b381b76ea378ee8629d1ed861a3899e075
 F src/malloc.c 92d59a007d7a42857d4e9454aa25b6b703286be1
 F src/mem0.c 6a55ebe57c46ca1a7d98da93aaa07f99f1059645
 F src/mem1.c 00bd8265c81abb665c48fea1e0c234eb3b922206
@@ -170,8 +170,8 @@ F src/parse.y 12b7ebd61ea54f0e1b1083ff69cc2c8ce9353d58
 F src/pcache.c 09d38c44ab275db581f7a2f6ff8b9bc7f8c0faaa
 F src/pcache.h c683390d50f856d4cd8e24342ae62027d1bb6050
 F src/pcache1.c d548e31beafa792d1994b663a29a5303569efc4e
-F src/pragma.c 4221eb822d7cdb1fb69be555b189e15e5a24b6b5
-F src/prepare.c eb4944d9f7bfa13eb42a7416ed9aaed4de4d0bf3
+F src/pragma.c 672c5e453d6321fdcfd76ffe346d99cae54fcddb
+F src/prepare.c cec63cb151fcaeee00006ec5376698310caea56a
 F src/printf.c 585a36b6a963df832cfb69505afa3a34ed5ef8a1
 F src/random.c cd4a67b3953b88019f8cd4ccd81394a8ddfaba50
 F src/resolve.c 1c0f32b64f8e3f555fe1f732f9d6f501a7f05706
@@ -234,16 +234,16 @@ F src/trigger.c ec4813709e990a169b6923293e839fa5dfd64282
 F src/update.c 81911be16ece3c3e7716aa18565b4814ec41f8b9
 F src/utf.c d83650c3ea08f7407bd9d0839d9885241c209c60
 F src/util.c cd997077bad039efc0597eb027c929658f93c018
-F src/vacuum.c 924bd1bcee2dfb05376f79845bd3b4cec7b54b2f
-F src/vdbe.c a45a6a0daf2161797d50b3b5b8a3e0e4debf2d2b
+F src/vacuum.c 3b2b0998f4f277e4bc61469c2d78d8424d02899b
+F src/vdbe.c 6b15a8fb9bb5d5abd232fbc72cc6410c2fd70c1b
 F src/vdbe.h 4de0efb4b0fdaaa900cf419b35c458933ef1c6d2
 F src/vdbeInt.h e1c6254641168507d25b46affb6dfb53c782f553
 F src/vdbeapi.c a09ad9164cafc505250d5dd6b69660c960f1308c
-F src/vdbeaux.c 77921792f7ebae267490816deb6a9488f938fa85
+F src/vdbeaux.c e97565fb2fea822a2e853370c440b493ef09d7e7
 F src/vdbeblob.c c3ccb7c8732858c680f442932e66ad06bb036562
 F src/vdbemem.c 0498796b6ffbe45e32960d6a1f5adfb6e419883b
 F src/vdbetrace.c 3ba13bc32bdf16d2bdea523245fd16736bed67b5
-F src/vtab.c e1edca38c4c4310710635bb91bb3c87fdf60f21d
+F src/vtab.c 341ae69e949ce583c1729b0177f62ab821e8b42f
 F src/wal.c 7334009b396285b658a95a3b6bc6d2b016a1f794
 F src/wal.h 7a5fbb00114b7f2cd40c7e1003d4c41ce9d26840
 F src/walker.c 3112bb3afe1d85dc52317cb1d752055e9a781f8f
@@ -926,7 +926,11 @@ F tool/speedtest8.c 2902c46588c40b55661e471d7a86e4dd71a18224
 F tool/speedtest8inst1.c 293327bc76823f473684d589a8160bde1f52c14e
 F tool/split-sqlite3c.tcl d9be87f1c340285a3e081eb19b4a247981ed290c
 F tool/vdbe-compress.tcl d70ea6d8a19e3571d7ab8c9b75cba86d1173ff0f
-P 20afd81a4cf4d23962ec841bbd375f36a5156fb6
-R 25d34b3e2efbdd1c8e0ceadec6512306
-U dan
-Z 659aea6fa897bf521b0a686e5d197299
+P 71a799b02a3b3cf2e12758dea29fd2465bbec3e1
+R 5fca8a4df9fe5cb6d589b9d60d83b4fc
+T *bgcolor * #d3a8bc
+T *branch * schema-parse-refactor
+T *sym-schema-parse-refactor *
+T -sym-trunk *
+U drh
+Z 80e5b841d301ef316c4772ca966c9795

diff --git a/manifest.uuid b/manifest.uuid
index fa61c3c6519bcfb23e049cbd1e585ef4ce128a37..8ad8e8fd350a4b16525cd472d3ca00ea1b1a930f 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-71a799b02a3b3cf2e12758dea29fd2465bbec3e1
\ No newline at end of file
+6a8ad6e31e0d2b8a5ace38faf0efd805155ee5f3
\ No newline at end of file

diff --git a/src/attach.c b/src/attach.c
index 37b61935f39835000ae04f84ea3cae469731f60f..fe88aa73cdccc507adc6295427d4f539b8c6466e 100644 (file)
--- a/src/attach.c
+++ b/src/attach.c
@@ -200,7 +200,7 @@ static void attachFunc(
       db->aDb[iDb].pBt = 0;
       db->aDb[iDb].pSchema = 0;
     }
-    sqlite3ResetInternalSchema(db, 0);
+    sqlite3ResetInternalSchema(db, -1);
     db->nDb = iDb;
     if( rc==SQLITE_NOMEM || rc==SQLITE_IOERR_NOMEM ){
       db->mallocFailed = 1;
@@ -272,7 +272,7 @@ static void detachFunc(
   sqlite3BtreeClose(pDb->pBt);
   pDb->pBt = 0;
   pDb->pSchema = 0;
-  sqlite3ResetInternalSchema(db, 0);
+  sqlite3ResetInternalSchema(db, -1);
   return;
 
 detach_error:

diff --git a/src/backup.c b/src/backup.c
index 82be9635b1295929f09926a6296edb9ad1467247..c062744c5c1f9f037273dd853c2fac96a3e7d231 100644 (file)
--- a/src/backup.c
+++ b/src/backup.c
@@ -401,7 +401,7 @@ int sqlite3_backup_step(sqlite3_backup *p, int nPage){
       int nDestTruncate;
   
       if( p->pDestDb ){
-        sqlite3ResetInternalSchema(p->pDestDb, 0);
+        sqlite3ResetInternalSchema(p->pDestDb, -1);
       }
 
       /* Set nDestTruncate to the final number of pages in the destination

diff --git a/src/build.c b/src/build.c
index bf3273fc848eaaf480cb1594d548e41af6b02933..c7cd6363d9b1823574b0057857e04f8d02e2887c 100644 (file)
--- a/src/build.c
+++ b/src/build.c
@@ -393,26 +393,34 @@ void sqlite3UnlinkAndDeleteIndex(sqlite3 *db, int iDb, const char *zIdxName){
 ** if there were schema changes during the transaction or if a
 ** schema-cookie mismatch occurs.
 **
-** If iDb==0 then reset the internal schema tables for all database
-** files.  If iDb>=1 then reset the internal schema for only the
+** If iDb<0 then reset the internal schema tables for all database
+** files.  If iDb>=0 then reset the internal schema for only the
 ** single file indicated.
 */
 void sqlite3ResetInternalSchema(sqlite3 *db, int iDb){
   int i, j;
-  assert( iDb>=0 && iDb<db->nDb );
+  assert( iDb<db->nDb );
 
-  if( iDb==0 ){
-    sqlite3BtreeEnterAll(db);
+  if( iDb>=0 ){
+    /* Case 1:  Reset the single schema identified by iDb */
+    Db *pDb = &db->aDb[iDb];
+    if( pDb->pSchema ){
+      assert(iDb==1 || (pDb->pBt && sqlite3BtreeHoldsMutex(pDb->pBt)));
+      sqlite3SchemaFree(pDb->pSchema);
+    }
+    return;
   }
-  for(i=iDb; i<db->nDb; i++){
+  /* Case 2 (from here to the end): Reset all schemas for all attached
+  ** databases. */
+  assert( iDb<0 );
+  sqlite3BtreeEnterAll(db);
+  for(i=0; i<db->nDb; i++){
     Db *pDb = &db->aDb[i];
     if( pDb->pSchema ){
       assert(i==1 || (pDb->pBt && sqlite3BtreeHoldsMutex(pDb->pBt)));
       sqlite3SchemaFree(pDb->pSchema);
     }
-    if( iDb>0 ) return;
   }
-  assert( iDb==0 );
   db->flags &= ~SQLITE_InternChanges;
   sqlite3VtabUnlockList(db);
   sqlite3BtreeLeaveAll(db);

diff --git a/src/main.c b/src/main.c
index 03097498c5248dce4a8fa3cc1b3ec1667ac164ef..ca862edc7f0634493a28de0bf53952826fb8790a 100644 (file)
--- a/src/main.c
+++ b/src/main.c
@@ -687,7 +687,7 @@ int sqlite3_close(sqlite3 *db){
   }
   sqlite3_mutex_enter(db->mutex);
 
-  sqlite3ResetInternalSchema(db, 0);
+  sqlite3ResetInternalSchema(db, -1);
 
   /* If a transaction is open, the ResetInternalSchema() call above
   ** will not have called the xDisconnect() method on any virtual
@@ -730,7 +730,7 @@ int sqlite3_close(sqlite3 *db){
       }
     }
   }
-  sqlite3ResetInternalSchema(db, 0);
+  sqlite3ResetInternalSchema(db, -1);
 
   /* Tell the code in notify.c that the connection no longer holds any
   ** locks and does not require any further unlock-notify callbacks.
@@ -821,7 +821,7 @@ void sqlite3RollbackAll(sqlite3 *db){
 
   if( db->flags&SQLITE_InternChanges ){
     sqlite3ExpirePreparedStatements(db);
-    sqlite3ResetInternalSchema(db, 0);
+    sqlite3ResetInternalSchema(db, -1);
   }
 
   /* Any deferred constraint violations have now been resolved. */

diff --git a/src/pragma.c b/src/pragma.c
index db55e4bb41fa28af2ce856e3f8ad34ba651a2375..0a092e8c3eae6a75997c523b66c0624ccfa55f9a 100644 (file)
--- a/src/pragma.c
+++ b/src/pragma.c
@@ -115,7 +115,7 @@ static int invalidateTempStorage(Parse *pParse){
     }
     sqlite3BtreeClose(db->aDb[1].pBt);
     db->aDb[1].pBt = 0;
-    sqlite3ResetInternalSchema(db, 0);
+    sqlite3ResetInternalSchema(db, -1);
   }
   return SQLITE_OK;
 }

diff --git a/src/prepare.c b/src/prepare.c
index 45654ecfca72ec571497ba2da1365fa12ea2a0b9..0687ddea42a4d53218c304d237b9a856ca184345 100644 (file)
--- a/src/prepare.c
+++ b/src/prepare.c
@@ -338,7 +338,7 @@ static int sqlite3InitOne(sqlite3 *db, int iDb, char **pzErrMsg){
   }
   if( db->mallocFailed ){
     rc = SQLITE_NOMEM;
-    sqlite3ResetInternalSchema(db, 0);
+    sqlite3ResetInternalSchema(db, -1);
   }
   if( rc==SQLITE_OK || (db->flags&SQLITE_RecoveryMode)){
     /* Black magic: If the SQLITE_RecoveryMode flag is set, then consider
@@ -613,7 +613,7 @@ static int sqlite3Prepare(
     schemaIsValid(pParse);
   }
   if( pParse->rc==SQLITE_SCHEMA ){
-    sqlite3ResetInternalSchema(db, 0);
+    sqlite3ResetInternalSchema(db, -1);
   }
   if( db->mallocFailed ){
     pParse->rc = SQLITE_NOMEM;

diff --git a/src/vacuum.c b/src/vacuum.c
index 4babf5b4098946e86da836c27e896a79b47c067e..5ca39ae1e03f83b5ec3c41eb54333c9b8744de9a 100644 (file)
--- a/src/vacuum.c
+++ b/src/vacuum.c
@@ -335,8 +335,9 @@ end_of_vacuum:
     pDb->pSchema = 0;
   }
 
-  sqlite3ResetInternalSchema(db, 0);
+  sqlite3ResetInternalSchema(db, -1);
 
   return rc;
 }
+
 #endif  /* SQLITE_OMIT_VACUUM && SQLITE_OMIT_ATTACH */

diff --git a/src/vdbe.c b/src/vdbe.c
index ddf507ee9da2458c8bd0b6511ef8d7545cbd2d87..0c790d65024a247a2fb83078356703118726d6f5 100644 (file)
--- a/src/vdbe.c
+++ b/src/vdbe.c
@@ -2649,7 +2649,7 @@ case OP_Savepoint: {
         }
         if( p1==SAVEPOINT_ROLLBACK && (db->flags&SQLITE_InternChanges)!=0 ){
           sqlite3ExpirePreparedStatements(db);
-          sqlite3ResetInternalSchema(db, 0);
+          sqlite3ResetInternalSchema(db, -1);
           db->flags = (db->flags | SQLITE_InternChanges);
         }
       }
@@ -5946,7 +5946,7 @@ vdbe_error_halt:
   sqlite3VdbeHalt(p);
   if( rc==SQLITE_IOERR_NOMEM ) db->mallocFailed = 1;
   rc = SQLITE_ERROR;
-  if( resetSchemaOnFault ) sqlite3ResetInternalSchema(db, 0);
+  if( resetSchemaOnFault ) sqlite3ResetInternalSchema(db, -1);
 
   /* This is the only way out of this procedure.  We have to
   ** release the mutexes on btrees that were acquired at the

diff --git a/src/vdbeaux.c b/src/vdbeaux.c
index 7cab12f78daae6a76f04b3b87ba1dd018bc9203e..a2f4a2b484678a2d9bffe3871f1e605bb951dd53 100644 (file)
--- a/src/vdbeaux.c
+++ b/src/vdbeaux.c
@@ -2191,7 +2191,7 @@ int sqlite3VdbeHalt(Vdbe *p){
   
     /* Rollback or commit any schema changes that occurred. */
     if( p->rc!=SQLITE_OK && db->flags&SQLITE_InternChanges ){
-      sqlite3ResetInternalSchema(db, 0);
+      sqlite3ResetInternalSchema(db, -1);
       db->flags = (db->flags | SQLITE_InternChanges);
     }
 

diff --git a/src/vtab.c b/src/vtab.c
index b9f1e6f34864ede88542685247247278777c5a96..30e302deafa7d0de4e675d4e3aad0ad12cf86de6 100644 (file)
--- a/src/vtab.c
+++ b/src/vtab.c
@@ -48,7 +48,7 @@ static int createModule(
     if( pDel==pMod ){
       db->mallocFailed = 1;
     }
-    sqlite3ResetInternalSchema(db, 0);
+    sqlite3ResetInternalSchema(db, -1);
   }else if( xDestroy ){
     xDestroy(pAux);
   }