Add support for TEMPORARY triggers. Such triggers can write temporary or

permanent tables. (CVS 926)

FossilOrigin-Name: 58ddd587b0f5d565ae3b0ba3a1fa5c20d459f3fc

manifest

@@ -1,5 +1,5 @@
-C Add\smore\stests\sfor\sthe\sin-memory\sdatabase.\s(CVS\s925)
+C Add\ssupport\sfor\sTEMPORARY\striggers.\s\sSuch\striggers\scan\swrite\stemporary\sor\npermanent\stables.\s(CVS\s926)
-D 2003-04-20T23:45:23
+D 2003-04-21T18:48:46
 F Makefile.in 004acec253ecdde985c8ecd5b7c9accdb210378f
 F Makefile.linux-gcc b86a99c493a5bfb402d1d9178dcdc4bd4b32f906
 F README f1de682fbbd94899d50aca13d387d1b3fd3be2dd
@@ -24,7 +24,7 @@ F src/auth.c 2dd558dba4d8ffbed25fe1644e9af242f389f3e9
 F src/btree.c b9487cceb9ea78af9cbae9def34114902f511736
 F src/btree.h 529c98cb0715c62214544fbbe50b946f99a85540
 F src/btree_rb.c 97375d44bc2cf93b6312acd0f3276177c20e77bb
-F src/build.c 66f8ca2457dfdcc6c45e1606696f337418a8c556
+F src/build.c 90fc1b15d5e69316ffb979a11052ba6743e9b556
 F src/copy.c 8699e571994934c78f70761a1458d7b9e9e75073
 F src/delete.c af65b26d9d13abbf63fdc4e97b88d26c700b04bb
 F src/encode.c faf03741efe921755ec371cf4a6984536de00042
@@ -39,7 +39,7 @@ F src/os.c 7274951ed6894f383cb889342267ded07caf339b
 F src/os.h aa52f0c9da321ff6134d19f2ca959e18e33615d0
 F src/pager.c df4c81350cbd80c1ab48341ae0768ba78d99ad49
 F src/pager.h e3702f7d384921f6cd5ce0b3ed589185433e9f6c
-F src/parse.y ad40843ae5462ba32606d55c53c2c8a9e56dd1ce
+F src/parse.y 15ae47e7dd84304c1c6ae9205558405127977541
 F src/pragma.c aef327bd597e15f0d31f45b042bd2797cca65039
 F src/printf.c fc5fdef6e92ad205005263661fe9716f55a49f3e
 F src/random.c 19e8e00fe0df32a742f115773f57651be327cabe
@@ -47,15 +47,15 @@ F src/select.c 07140aaf5f2e209dd7bf8a681401a412ce16dc04
 F src/shell.c a0b7043713713ff45f666ce6b3c03a64109a8bb5
 F src/shell.tcl 27ecbd63dd88396ad16d81ab44f73e6c0ea9d20e
 F src/sqlite.h.in f49c2cdec7d24cb03e496a1ca519e16306495ee1
-F src/sqliteInt.h c4f4866cce8f069574268969167b5f8041802edd
+F src/sqliteInt.h 331d92aa826c5230247d97818b291f38aba21a11
 F src/table.c eed2098c9b577aa17f8abe89313a9c4413f57d63
 F src/tclsqlite.c 7a072c3c8ba9796edc25e5ffa62b68558134e192
 F src/test1.c 7ad4e6308dde0bf5a0f0775ce20cb2ec37a328f8
 F src/test2.c 5014337d8576b731cce5b5a14bec4f0daf432700
 F src/test3.c 30985ebdfaf3ee1462a9b0652d3efbdc8d9798f5
 F src/threadtest.c d641a5219e718e18a1a80a50eb9bb549f451f42e
-F src/tokenize.c a88cfb6f698d047e14d5064fa6c4ecb709bf8fa4
+F src/tokenize.c 067d1a477a94af7712ca74e09aaa6bd0f7299527
-F src/trigger.c 45b67f6c4338245288e4662c6a5b802ae3a66e5d
+F src/trigger.c c461789fb90df04b4c43b0d07a7aede8f453d9bc
 F src/update.c 803c13ad967850fb18443394e0a5c2b0f0d7ce6f
 F src/util.c 87635cfdfffa056a8d3147719357aa442374f78c
 F src/vacuum.c e24781e38db36d1c9f578b6b3613bf0989ebd63c
@@ -120,7 +120,7 @@ F test/tclsqlite.test 62773bcb94f7d7b69f1ab05c0ae07a22c737440f
 F test/temptable.test 6feff1960c707e924d5462356c5303943dac4a8e
 F test/tester.tcl d7a5835edaf118539241145d8188f0822b673488
 F test/trans.test 75e7a171b5d2d94ee56766459113e2ad0e5f809d
-F test/trigger1.test 6fa21c3996e5543b4b6ceb8def84472002ab25e7
+F test/trigger1.test 61ef41666f066ac417730dc26056053a7c36cd11
 F test/trigger2.test ab4c743bb96cee96ab5a17c5edfd57a9134329d6
 F test/trigger3.test 870afef7997a5b86bf3ea893ce0c2e85d6356c72
 F test/trigger4.test 9a5c1406344d743020c2753ae8d6dfe6eb75f818
@@ -165,7 +165,7 @@ F www/speed.tcl cb4c10a722614aea76d2c51f32ee43400d5951be
 F www/sqlite.tcl ae3dcfb077e53833b59d4fcc94d8a12c50a44098
 F www/tclsqlite.tcl 1db15abeb446aad0caf0b95b8b9579720e4ea331
 F www/vdbe.tcl 2013852c27a02a091d39a766bc87cff329f21218
-P fb89adf4d1325c5ea471759ebfd8df7faa4f9a80
+P 11cab41c4f02cdddc4fd3f57555573ac2814a81b
-R 5155025990322dc1039d8bac43cc6a4c
+R fdfcbaff78e43d8a367933863118062c
 U drh
-Z 91bd6b460f5c66d00bbb9e74c7457add
+Z 56b9d2fa20bf8f19c521466c7923ae4d

manifest.uuid

@@ -1 +1 @@
-11cab41c4f02cdddc4fd3f57555573ac2814a81b
+58ddd587b0f5d565ae3b0ba3a1fa5c20d459f3fc

src/build.c

@@ -23,7 +23,7 @@
 **     ROLLBACK
 **     PRAGMA
 **
-** $Id: build.c,v 1.147 2003/04/20 00:00:24 drh Exp $
+** $Id: build.c,v 1.148 2003/04/21 18:48:46 drh Exp $
 */
 #include "sqliteInt.h"
 #include <ctype.h>
@@ -159,6 +159,10 @@ Table *sqliteLocateTable(Parse *pParse, const char *zName, const char *zDbase){
   if( p==0 ){
     if( zDbase ){
       sqliteErrorMsg(pParse, "no such table: %s.%s", zDbase, zName);
+    }else if( (pParse->useDb==0 || pParse->useDb>=2) 
+               && sqliteFindTable(db, zName, 0)!=0 ){
+      sqliteErrorMsg(pParse, "table \"%s\" is not in database \"%s\"",
+         zName, zUse);
     }else{
       sqliteErrorMsg(pParse, "no such table: %s", zName);
     }

src/parse.y

@@ -14,7 +14,7 @@
 ** the parser.  Lemon will also generate a header file containing
 ** numeric codes for all of the tokens.
 **
-** @(#) $Id: parse.y,v 1.95 2003/04/17 22:57:54 drh Exp $
+** @(#) $Id: parse.y,v 1.96 2003/04/21 18:48:46 drh Exp $
 */
 %token_prefix TK_
 %token_type {Token}
@@ -759,15 +759,18 @@ plus_opt ::= PLUS.
 plus_opt ::= .
 
 //////////////////////////// The CREATE TRIGGER command /////////////////////
-cmd ::= CREATE(A) TRIGGER nm(B) trigger_time(C) trigger_event(D) 
+
-                  ON nm(E) dbnm(DB)
+cmd ::= CREATE(A) trigger_decl BEGIN trigger_cmd_list(S) END(Z). {
-                  foreach_clause(F) when_clause(G)
-                  BEGIN trigger_cmd_list(S) END(Z). {
-  SrcList *pTab = sqliteSrcListAppend(0, &E, &DB);
   Token all;
   all.z = A.z;
   all.n = (Z.z - A.z) + Z.n;
-  sqliteCreateTrigger(pParse, &B, C, D.a, D.b, pTab, F, G, S, &all);
+  sqliteFinishTrigger(pParse, S, &all);
+}
+
+trigger_decl ::= temp(T) TRIGGER nm(B) trigger_time(C) trigger_event(D)
+                 ON nm(E) dbnm(DB) foreach_clause(F) when_clause(G). {
+  SrcList *pTab = sqliteSrcListAppend(0, &E, &DB);
+  sqliteBeginTrigger(pParse, &B, C, D.a, D.b, pTab, F, G, T);
 }
 
 %type trigger_time  {int}
@@ -793,6 +796,7 @@ when_clause(A) ::= .             { A = 0; }
 when_clause(A) ::= WHEN expr(X). { A = X; }
 
 %type trigger_cmd_list {TriggerStep *}
+%destructor trigger_cmd_list {sqliteDeleteTriggerStep($$);}
 trigger_cmd_list(A) ::= trigger_cmd(X) SEMI trigger_cmd_list(Y). {
   X->pNext = Y;
   A = X;
@@ -800,6 +804,7 @@ trigger_cmd_list(A) ::= trigger_cmd(X) SEMI trigger_cmd_list(Y). {
 trigger_cmd_list(A) ::= . { A = 0; }
 
 %type trigger_cmd {TriggerStep *}
+%destructor trigger_cmd {sqliteDeleteTriggerStep($$);}
 // UPDATE 
 trigger_cmd(A) ::= UPDATE orconf(R) nm(X) SET setlist(Y) where_opt(Z).  
                { A = sqliteTriggerUpdateStep(&X, Y, Z, R); }

src/sqliteInt.h

@@ -11,7 +11,7 @@
 *************************************************************************
 ** Internal interface definitions for SQLite.
 **
-** @(#) $Id: sqliteInt.h,v 1.176 2003/04/20 00:00:24 drh Exp $
+** @(#) $Id: sqliteInt.h,v 1.177 2003/04/21 18:48:47 drh Exp $
 */
 #include "config.h"
 #include "sqlite.h"
@@ -832,7 +832,8 @@ struct Parse {
   int nSet;            /* Number of sets used so far */
   int nAgg;            /* Number of aggregate expressions */
   AggExpr *aAgg;       /* An array of aggregate expressions */
-  TriggerStack *trigStack;
+  Trigger *pNewTrigger;     /* Trigger under construct by a CREATE TRIGGER */
+  TriggerStack *trigStack;  /* Trigger actions being coded */
 };
 
 /*
@@ -853,9 +854,9 @@ struct Parse {
 struct Trigger {
   char *name;             /* The name of the trigger                        */
   char *table;            /* The table or view to which the trigger applies */
-  int iDb;                /* Database containing this trigger               */
+  u8 iDb;                 /* Database containing this trigger               */
-  int op;                 /* One of TK_DELETE, TK_UPDATE, TK_INSERT         */
+  u8 op;                  /* One of TK_DELETE, TK_UPDATE, TK_INSERT         */
-  int tr_tm;              /* One of TK_BEFORE, TK_AFTER */
+  u8 tr_tm;               /* One of TK_BEFORE, TK_AFTER */
   Expr *pWhen;            /* The WHEN clause of the expresion (may be NULL) */
   IdList *pColumns;       /* If this is an UPDATE OF <column-list> trigger,
                              the <column-list> is stored here */
@@ -1094,13 +1095,14 @@ int sqliteSafetyOn(sqlite*);
 int sqliteSafetyOff(sqlite*);
 int sqliteSafetyCheck(sqlite*);
 void sqliteChangeCookie(sqlite*, Vdbe*);
-void sqliteCreateTrigger(Parse*, Token*, int, int, IdList*, SrcList*, 
+void sqliteBeginTrigger(Parse*, Token*,int,int,IdList*,SrcList*,int,Expr*,int);
-                         int, Expr*, TriggerStep*, Token*);
+void sqliteFinishTrigger(Parse*, TriggerStep*, Token*);
 void sqliteDropTrigger(Parse*, SrcList*, int);
 int sqliteTriggersExist(Parse* , Trigger* , int , int , int, ExprList*);
 int sqliteCodeRowTrigger(Parse*, int, ExprList*, int, Table *, int, int, 
                          int, int);
 void sqliteViewTriggers(Parse*, Table*, Expr*, int, ExprList*);
+void sqliteDeleteTriggerStep(TriggerStep*);
 TriggerStep *sqliteTriggerSelectStep(Select*);
 TriggerStep *sqliteTriggerInsertStep(Token*, IdList*, ExprList*, Select*, int);
 TriggerStep *sqliteTriggerUpdateStep(Token*, ExprList*, Expr*, int);

src/tokenize.c

@@ -15,7 +15,7 @@
 ** individual tokens and sends those tokens one-by-one over to the
 ** parser for analysis.
 **
-** $Id: tokenize.c,v 1.57 2003/04/16 02:17:36 drh Exp $
+** $Id: tokenize.c,v 1.58 2003/04/21 18:48:47 drh Exp $
 */
 #include "sqliteInt.h"
 #include "os.h"
@@ -487,6 +487,10 @@ abort_parse:
     sqliteDeleteTable(pParse->db, pParse->pNewTable);
     pParse->pNewTable = 0;
   }
+  if( pParse->pNewTrigger ){
+    sqliteDeleteTrigger(pParse->pNewTrigger);
+    pParse->pNewTrigger = 0;
+  }
   if( nErr>0 && (pParse->rc==SQLITE_OK || pParse->rc==SQLITE_DONE) ){
     pParse->rc = SQLITE_ERROR;
   }

src/trigger.c

@@ -15,7 +15,7 @@
 /*
 ** Delete a linked list of TriggerStep structures.
 */
-static void sqliteDeleteTriggerStep(TriggerStep *pTriggerStep){
+void sqliteDeleteTriggerStep(TriggerStep *pTriggerStep){
   while( pTriggerStep ){
     TriggerStep * pTmp = pTriggerStep;
     pTriggerStep = pTriggerStep->pNext;
@@ -31,11 +31,14 @@ static void sqliteDeleteTriggerStep(TriggerStep *pTriggerStep){
 }
 
 /*
-** This is called by the parser when it sees a CREATE TRIGGER statement. See
+** This is called by the parser when it sees a CREATE TRIGGER statement
-** comments surrounding struct Trigger in sqliteInt.h for a description of 
+** up to the point of the BEGIN before the trigger actions.  A Trigger
-** how triggers are stored.
+** structure is generated based on the information available and stored
+** in pParse->pNewTrigger.  After the trigger actions have been parsed, the
+** sqliteFinishTrigger() function is called to complete the trigger
+** construction process.
 */
-void sqliteCreateTrigger(
+void sqliteBeginTrigger(
   Parse *pParse,      /* The parse context of the CREATE TRIGGER statement */
   Token *pName,       /* The name of the trigger */
   int tr_tm,          /* One of TK_BEFORE, TK_AFTER , TK_INSTEAD */
@@ -44,17 +47,17 @@ void sqliteCreateTrigger(
   SrcList *pTableName,/* The name of the table/view the trigger applies to */
   int foreach,        /* One of TK_ROW or TK_STATEMENT */
   Expr *pWhen,        /* WHEN clause */
-  TriggerStep *pStepList, /* The triggered program */
+  int isTemp          /* True if the TEMPORARY keyword is present */
-  Token *pAll             /* Token that describes the complete CREATE TRIGGER */
 ){
   Trigger *nt;
   Table   *tab;
   char *zName = 0;        /* Name of the trigger */
   sqlite *db = pParse->db;
+  int iDb;                /* When database to store the trigger in */
 
   /* Check that: 
   ** 1. the trigger name does not already exist.
-  ** 2. the table (or view) does exist.
+  ** 2. the table (or view) does exist in the same database as the trigger.
   ** 3. that we are not trying to create a trigger on the sqlite_master table
   ** 4. That we are not trying to create an INSTEAD OF trigger on a table.
   ** 5. That we are not trying to create a BEFORE or AFTER trigger on a view.
@@ -65,14 +68,15 @@ void sqliteCreateTrigger(
   if( !tab ){
     goto trigger_cleanup;
   }
-  if( tab->iDb>=2 && !pParse->initFlag ){
+  iDb = isTemp ? 1 : tab->iDb;
+  if( iDb>=2 && !pParse->initFlag ){
     sqliteErrorMsg(pParse, "triggers may not be added to auxiliary "
        "database %s", db->aDb[tab->iDb].zName);
     goto trigger_cleanup;
   }
 
   zName = sqliteStrNDup(pName->z, pName->n);
-  if( sqliteHashFind(&(db->aDb[tab->iDb].trigHash), zName,pName->n+1) ){
+  if( sqliteHashFind(&(db->aDb[iDb].trigHash), zName,pName->n+1) ){
     sqliteErrorMsg(pParse, "trigger %T already exists", pName);
     goto trigger_cleanup;
   }
@@ -94,7 +98,7 @@ void sqliteCreateTrigger(
 #ifndef SQLITE_OMIT_AUTHORIZATION
   {
     int code = SQLITE_CREATE_TRIGGER;
-    if( tab->iDb==1 ) code = SQLITE_CREATE_TEMP_TRIGGER;
+    if( tab->iDb==1 || isTemp ) code = SQLITE_CREATE_TEMP_TRIGGER;
     if( sqliteAuthCheck(pParse, code, zName, tab->zName) ){
       goto trigger_cleanup;
     }
@@ -115,20 +119,42 @@ void sqliteCreateTrigger(
   zName = 0;
   nt->table = sqliteStrDup(pTableName->a[0].zName);
   if( sqlite_malloc_failed ) goto trigger_cleanup;
-  nt->iDb = tab->iDb;
+  nt->iDb = iDb;
   nt->op = op;
   nt->tr_tm = tr_tm;
   nt->pWhen = sqliteExprDup(pWhen);
-  sqliteExprDelete(pWhen);
   nt->pColumns = sqliteIdListDup(pColumns);
-  sqliteIdListDelete(pColumns);
   nt->foreach = foreach;
+  assert( pParse->pNewTrigger==0 );
+  pParse->pNewTrigger = nt;
+
+trigger_cleanup:
+  sqliteFree(zName);
+  sqliteSrcListDelete(pTableName);
+  sqliteIdListDelete(pColumns);
+  sqliteExprDelete(pWhen);
+}
+
+/*
+** This routine is called after all of the trigger actions have been parsed
+** in order to complete the process of building the trigger.
+*/
+void sqliteFinishTrigger(
+  Parse *pParse,          /* Parser context */
+  TriggerStep *pStepList, /* The triggered program */
+  Token *pAll             /* Token that describes the complete CREATE TRIGGER */
+){
+  Trigger *nt;              /* The trigger whose construction is finishing up */
+  sqlite *db = pParse->db;  /* The database */
+
+  if( pParse->nErr || pParse->pNewTrigger==0 ) goto triggerfinish_cleanup;
+  nt = pParse->pNewTrigger;
+  pParse->pNewTrigger = 0;
   nt->step_list = pStepList;
   while( pStepList ){
     pStepList->pTrig = nt;
     pStepList = pStepList->pNext;
   }
-  pStepList = nt->step_list;
 
   /* if we are not initializing, and this trigger is not on a TEMP table, 
   ** build the sqlite_master entry
@@ -149,16 +175,14 @@ void sqliteCreateTrigger(
 
     /* Make an entry in the sqlite_master table */
     v = sqliteGetVdbe(pParse);
-    if( v==0 ) goto trigger_cleanup;
+    if( v==0 ) goto triggerfinish_cleanup;
     sqliteBeginWriteOperation(pParse, 0, 0);
-    sqliteOpenMasterTable(v, tab->iDb);
+    sqliteOpenMasterTable(v, nt->iDb==1);
     addr = sqliteVdbeAddOpList(v, ArraySize(insertTrig), insertTrig);
-    sqliteVdbeChangeP3(v, addr, tab->iDb ? TEMP_MASTER_NAME : MASTER_NAME,
-                       P3_STATIC);
     sqliteVdbeChangeP3(v, addr+2, nt->name, 0); 
     sqliteVdbeChangeP3(v, addr+3, nt->table, 0); 
     sqliteVdbeChangeP3(v, addr+5, pAll->z, pAll->n);
-    if( tab->iDb==0 ){
+    if( nt->iDb==0 ){
       sqliteChangeCookie(db, v);
     }
     sqliteVdbeAddOp(v, OP_Close, 0, 0);
@@ -166,26 +190,20 @@ void sqliteCreateTrigger(
   }
 
   if( !pParse->explain ){
-    /* Stick it in the hash-table */
+    Table *pTab;
-    sqliteHashInsert(&(db->aDb[nt->iDb].trigHash), nt->name, pName->n + 1, nt);
+    sqliteHashInsert(&db->aDb[nt->iDb].trigHash, 
-
+                     nt->name, strlen(nt->name)+1, nt);
-    /* Attach it to the table object */
+    pTab = sqliteLocateTable(pParse, nt->table, 0);
-    nt->pNext = tab->pTrigger;
+    assert( pTab!=0 );
-    tab->pTrigger = nt;
+    nt->pNext = pTab->pTrigger;
-    sqliteSrcListDelete(pTableName);
+    pTab->pTrigger = nt;
-    return;
   }else{
-    sqliteFree(nt->name);
+    sqliteDeleteTrigger(nt);
-    sqliteFree(nt->table);
-    sqliteFree(nt);
   }
 
-trigger_cleanup:
+triggerfinish_cleanup:
-
+  sqliteDeleteTrigger(pParse->pNewTrigger);
-  sqliteFree(zName);
+  pParse->pNewTrigger = 0;
-  sqliteSrcListDelete(pTableName);
-  sqliteIdListDelete(pColumns);
-  sqliteExprDelete(pWhen);
   sqliteDeleteTriggerStep(pStepList);
 }
 
@@ -322,6 +340,7 @@ TriggerStep *sqliteTriggerDeleteStep(Token *pTableName, Expr *pWhere){
 ** Recursively delete a Trigger structure
 */
 void sqliteDeleteTrigger(Trigger *pTrigger){
+  if( pTrigger==0 ) return;
   sqliteDeleteTriggerStep(pTrigger->step_list);
   sqliteFree(pTrigger->name);
   sqliteFree(pTrigger->table);
@@ -366,7 +385,7 @@ void sqliteDropTrigger(Parse *pParse, SrcList *pName, int nested){
     sqliteErrorMsg(pParse, "no such trigger: %S", pName, 0);
     goto drop_trigger_cleanup;
   }
-  assert( pTrigger->iDb>=0 && pTrigger->iDb<db->nDb );
+  assert( pTrigger->iDb<db->nDb );
   if( pTrigger->iDb>=2 ){
     sqliteErrorMsg(pParse, "triggers may not be removed from "
        "auxiliary database %s", db->aDb[pTrigger->iDb].zName);
@@ -374,18 +393,44 @@ void sqliteDropTrigger(Parse *pParse, SrcList *pName, int nested){
   }
   pTable = sqliteFindTable(db, pTrigger->table, db->aDb[pTrigger->iDb].zName);
   assert(pTable);
-  assert( pTable->iDb==pTrigger->iDb );
+  assert( pTable->iDb==pTrigger->iDb || pTrigger->iDb==1 );
 #ifndef SQLITE_OMIT_AUTHORIZATION
   {
     int code = SQLITE_DROP_TRIGGER;
-    if( pTable->iDb ) code = SQLITE_DROP_TEMP_TRIGGER;
+    if( pTrigger->iDb ) code = SQLITE_DROP_TEMP_TRIGGER;
     if( sqliteAuthCheck(pParse, code, pTrigger->name, pTable->zName) ||
-      sqliteAuthCheck(pParse, SQLITE_DELETE, SCHEMA_TABLE(pTable->iDb),0) ){
+      sqliteAuthCheck(pParse, SQLITE_DELETE, SCHEMA_TABLE(pTrigger->iDb),0) ){
       goto drop_trigger_cleanup;
     }
   }
 #endif
 
+  /* Generate code to destroy the database record of the trigger.
+  */
+  if( pTable!=0 && !nested && (v = sqliteGetVdbe(pParse))!=0 ){
+    int base;
+    static VdbeOp dropTrigger[] = {
+      { OP_Rewind,     0, ADDR(8),  0},
+      { OP_String,     0, 0,        0}, /* 1 */
+      { OP_MemStore,   1, 1,        0},
+      { OP_MemLoad,    1, 0,        0}, /* 3 */
+      { OP_Column,     0, 1,        0},
+      { OP_Ne,         0, ADDR(7),  0},
+      { OP_Delete,     0, 0,        0},
+      { OP_Next,       0, ADDR(3),  0}, /* 7 */
+    };
+
+    sqliteBeginWriteOperation(pParse, 0, 0);
+    sqliteOpenMasterTable(v, pTrigger->iDb);
+    base = sqliteVdbeAddOpList(v,  ArraySize(dropTrigger), dropTrigger);
+    sqliteVdbeChangeP3(v, base+1, zName, 0);
+    if( pTrigger->iDb==0 ){
+      sqliteChangeCookie(db, v);
+    }
+    sqliteVdbeAddOp(v, OP_Close, 0, 0);
+    sqliteEndWriteOperation(pParse);
+  }
+
   /*
    * If this is not an "explain", then delete the trigger structure.
    */
@@ -407,32 +452,6 @@ void sqliteDropTrigger(Parse *pParse, SrcList *pName, int nested){
     sqliteDeleteTrigger(pTrigger);
   }
 
-  /* Generate code to destroy the database record of the trigger.
-  */
-  if( pTable!=0 && !nested && (v = sqliteGetVdbe(pParse))!=0 ){
-    int base;
-    static VdbeOp dropTrigger[] = {
-      { OP_Rewind,     0, ADDR(8),  0},
-      { OP_String,     0, 0,        0}, /* 1 */
-      { OP_MemStore,   1, 1,        0},
-      { OP_MemLoad,    1, 0,        0}, /* 3 */
-      { OP_Column,     0, 1,        0},
-      { OP_Ne,         0, ADDR(7),  0},
-      { OP_Delete,     0, 0,        0},
-      { OP_Next,       0, ADDR(3),  0}, /* 7 */
-    };
-
-    sqliteBeginWriteOperation(pParse, 0, 0);
-    sqliteOpenMasterTable(v, pTable->iDb);
-    base = sqliteVdbeAddOpList(v,  ArraySize(dropTrigger), dropTrigger);
-    sqliteVdbeChangeP3(v, base+1, zName, 0);
-    if( pTable->iDb==0 ){
-      sqliteChangeCookie(db, v);
-    }
-    sqliteVdbeAddOp(v, OP_Close, 0, 0);
-    sqliteEndWriteOperation(pParse);
-  }
-
 drop_trigger_cleanup:
   sqliteSrcListDelete(pName);
 }
@@ -521,6 +540,7 @@ static int codeTriggerProgram(
     orconf = (orconfin == OE_Default)?pTriggerStep->orconf:orconfin;
     pParse->trigStack->orconf = orconf;
     pParse->useDb = pTriggerStep->pTrig->iDb;
+    if( pParse->useDb==1 ) pParse->useDb = -1;
     switch( pTriggerStep->op ){
       case TK_SELECT: {
 	Select * ss = sqliteSelectDup(pTriggerStep->pSelect);		  

test/trigger1.test

@@ -180,4 +180,91 @@ do_test trigger1-1.14 {
   }
 } {1 {cannot create AFTER trigger on view: v1}}
 
+# Check for memory leaks in the trigger parser
+#
+do_test trigger1-2.1 {
+  catchsql {
+    CREATE TRIGGER r1 AFTER INSERT ON t1 BEGIN
+      SELECT * FROM;  -- Syntax error
+    END;
+  }
+} {1 {near ";": syntax error}}
+do_test trigger1-2.2 {
+  catchsql {
+    CREATE TRIGGER r1 AFTER INSERT ON t1 BEGIN
+      SELECT * FROM t1;
+      SELECT * FROM;  -- Syntax error
+    END;
+  }
+} {1 {near ";": syntax error}}
+
+# Create a trigger that refers to a table that might not exist.
+#
+do_test trigger1-3.1 {
+  execsql {
+    CREATE TEMP TABLE t2(x,y);
+  }
+  catchsql {
+    CREATE TRIGGER r1 AFTER INSERT ON t1 BEGIN
+      INSERT INTO t2 VALUES(NEW.a,NEW.b);
+    END;
+  }
+} {0 {}}
+do_test trigger-3.2 {
+  catchsql {
+    INSERT INTO t1 VALUES(1,2);
+    SELECT * FROM t2;
+  }
+} {1 {table "t2" is not in database "main"}}
+do_test trigger-3.3 {
+  db close
+  set rc [catch {sqlite db test.db} err]
+  if {$rc} {lappend rc $err}
+  set rc
+} {0}
+do_test trigger-3.4 {
+  catchsql {
+    INSERT INTO t1 VALUES(1,2);
+    SELECT * FROM t2;
+  }
+} {1 {no such table: t2}}
+do_test trigger-3.5 {
+  catchsql {
+    CREATE TEMP TABLE t2(x,y);
+    INSERT INTO t1 VALUES(1,2);
+    SELECT * FROM t2;
+  }
+} {1 {table "t2" is not in database "main"}}
+do_test trigger-3.6 {
+  catchsql {
+    DROP TRIGGER r1;
+    CREATE TEMP TRIGGER r1 AFTER INSERT ON t1 BEGIN
+      INSERT INTO t2 VALUES(NEW.a,NEW.b);
+    END;
+    INSERT INTO t1 VALUES(1,2);
+    SELECT * FROM t2;
+  }
+} {0 {1 2}}
+do_test trigger-3.7 {
+  execsql {
+    DROP TABLE t2;
+    CREATE TABLE t2(x,y);
+    SELECT * FROM t2;
+  }
+} {}
+do_test trigger-3.8 {
+  execsql {
+    INSERT INTO t1 VALUES(3,4);
+    SELECT * FROM t1 UNION ALL SELECT * FROM t2;
+  }
+} {1 2 3 4 3 4}
+do_test trigger-3.9 {
+  db close
+  sqlite db test.db
+  execsql {
+    INSERT INTO t1 VALUES(5,6);
+    SELECT * FROM t1 UNION ALL SELECT * FROM t2;
+  }
+} {1 2 3 4 5 6 3 4}
+
 finish_test