Defer deleting Table objects associated with flattened subqueries until

all code has been generated, in case some expression node still references
the Table object.  Ticket #3346. (CVS 5650)

FossilOrigin-Name: d04d70336727a0db959c672e6c22cdaa0505dce5

manifest

@@ -1,5 +1,5 @@
-C Have\sthe\srtree\smodule\sset\sthe\sestimatedCost\soutput\svariable.\sTicket\s#3312.\s(CVS\s5649)
-D 2008-09-01T12:47:00
+C Defer\sdeleting\sTable\sobjects\sassociated\swith\sflattened\ssubqueries\suntil\nall\scode\shas\sbeen\sgenerated,\sin\scase\ssome\sexpression\snode\sstill\sreferences\nthe\sTable\sobject.\s\sTicket\s#3346.\s(CVS\s5650)
+D 2008-09-01T15:52:11
 F Makefile.arm-wince-mingw32ce-gcc fcd5e9cd67fe88836360bb4f9ef4cb7f8e2fb5a0
 F Makefile.in 689e14735f862a5553bceef206d8c13e29504e44
 F Makefile.linux-gcc d53183f4aa6a9192d249731c90dbdffbd2c68654
@@ -145,11 +145,11 @@ F src/prepare.c c197041e0c4770672cda75e6bfe10242f885e510
 F src/printf.c 785f87120589c1db672e37c6eb1087c456e6f84d
 F src/random.c 5c754319d38abdd6acd74601ee0105504adc508a
 F src/resolve.c a6abf83125bce0c80ba04acc27c3565155ad305c
-F src/select.c 8187927315ee592a8ee94d753b8a1a3625c33523
+F src/select.c eec7c5f28a0c75fdd8500630435af176bba73219
 F src/shell.c d83b578a8ccdd3e0e7fef4388a0887ce9f810967
 F src/sqlite.h.in c0e84a2d6e9f3263599174ff7261ba6daf730b4f
 F src/sqlite3ext.h 1e3887c9bd3ae66cb599e922824b04cd0d0f2c3e
-F src/sqliteInt.h e7f9e974763e93707ba4fe564b50744ba2a08658
+F src/sqliteInt.h 2243b0eadb5dd32de8f0a38571afedb711fa2cc5
 F src/sqliteLimit.h f435e728c6b620ef7312814d660a81f9356eb5c8
 F src/status.c 8caa772cd9310bc297280f7cf0ede4d69ed5b801
 F src/table.c 22744786199c9195720c15a7a42cb97b2e2728d8
@@ -180,7 +180,7 @@ F src/test_schema.c 4b4bf7bb329326458c491b0e6facd4c8c4c5b479
 F src/test_server.c f0a403b5f699c09bd2b1236b6f69830fd6221f6b
 F src/test_tclvar.c 9e42fa59d3d2f064b7ab8628e7ab2dc8a9fe93d4
 F src/test_thread.c d74fc445e0dba0e00806117eb449b307c0b146bf
-F src/tokenize.c 76fe4cb8a606c24c76843ee2170cf84085f40817
+F src/tokenize.c aaa5fa6a4536a9dd7c855a3f66f32508f1612138
 F src/trigger.c 649940b5bf5838a33721fb72372e7c9d1faf56a9
 F src/update.c f2cf6f00d542956bd49ba4b9815c2900d9225bf2
 F src/utf.c c63e6f69082f85c19ab88d62dedaf91d71ac1a50
@@ -229,7 +229,7 @@ F test/bitvec.test 62a512c3f7041d1df12558eb25990e5a19820571
 F test/blob.test 2a38d867bdf08f9ce081776acec1ac8d4bca66be
 F test/busy.test 76b4887f8b9160ba903c1ac22e8ff406ad6ae2f0
 F test/cache.test 3ff445c445742a7b6b9ba6e1d62a25263f9424b9
-F test/capi2.test cc64df7560a96f848f919ea2926c60acf639684b
+F test/capi2.test 36f87803c811b5986dd31eb5492cb704552776b4
 F test/capi3.test ffc1156d1f28738eb335df0b88dd294bb3c94c27
 F test/capi3b.test 664eb55318132f292f2c436f90906f578cad6b97
 F test/capi3c.test 208713e5f3a63442c3574c55b83baa7cf8ac5f28
@@ -555,6 +555,7 @@ F test/tkt3201.test 607d433ad2c1f6a8cb1af55aaca427f63c83191b
 F test/tkt3292.test 962465a0984a3b8c757efe59c2c59144871ee1dd
 F test/tkt3298.test a735582095ca2e90a0c1391c7e781a90de6c1f34
 F test/tkt3334.test ea13a53cb176e90571a76c86605b14a09efe366d
+F test/tkt3346.test 2f9a2be8621a87cbdb6283177dd419c7c46dd2a1
 F test/tokenize.test ce430a7aed48fc98301611429595883fdfcab5d7
 F test/trace.test 951cd0f5f571e7f36bf7bfe04be70f90fb16fb00
 F test/trans.test 2fd24cd7aa0b879d49a224cbd647d698f1e7ac5c
@@ -597,7 +598,7 @@ F test/vtabC.test 9f2d9eb84bf65e606d6616f20977c5a32a11f548
 F test/vtab_alter.test 3a299749fee97ca3d53bd55717f536e4a2284856
 F test/vtab_err.test 0d4d8eb4def1d053ac7c5050df3024fd47a3fbd8
 F test/vtab_shared.test c19b2555b807ef2ee014c882cdda5bc8d84fcf48
-F test/where.test 4f1b9a403bba6855681eb7e7e9230e5decb67309
+F test/where.test ea8e56f3c7b18fa4d250d32a08ffab44c0ff64ba
 F test/where2.test 7012c0ad022a54430dd22c98288d3f4d6599dbcf
 F test/where3.test 97d3936e6a443b968f1a61cdcc0f673252000e94
 F test/where4.test e9b9e2f2f98f00379e6031db6a6fca29bae782a2
@@ -628,7 +629,7 @@ F tool/speedtest16.c c8a9c793df96db7e4933f0852abb7a03d48f2e81
 F tool/speedtest2.tcl ee2149167303ba8e95af97873c575c3e0fab58ff
 F tool/speedtest8.c 1dbced29de5f59ba2ebf877edcadf171540374d1
 F tool/speedtest8inst1.c 293327bc76823f473684d589a8160bde1f52c14e
-P d68791e35d13f5ae4befeb0bb5f8ccaf14fd3763
-R cf8a1d32d459a4e4e9a02a25baa421e1
-U danielk1977
-Z d770b724d467b2bb63feddfe02dfb4bf
+P 483932c4e08901a11b7ab671073fd0a048b10d66
+R 952afbcc44da7926eca4d46e950df9fb
+U drh
+Z a76eb0281ee8fa910a9148137fb4d127

manifest.uuid

@@ -1 +1 @@
-483932c4e08901a11b7ab671073fd0a048b10d66
+d04d70336727a0db959c672e6c22cdaa0505dce5

src/select.c

@@ -12,7 +12,7 @@
 ** This file contains C code routines that are called by the parser
 ** to handle SELECT statements in SQLite.
 **
-** $Id: select.c,v 1.471 2008/08/26 12:56:14 drh Exp $
+** $Id: select.c,v 1.472 2008/09/01 15:52:11 drh Exp $
 */
 #include "sqliteInt.h"
 
@@ -2427,6 +2427,9 @@ static void substSelect(
   int iTable,          /* Table to be replaced */
   ExprList *pEList     /* Substitute values */
 ){
+  SrcList *pSrc;
+  struct SrcList_item *pItem;
+  int i;
   if( !p ) return;
   substExprList(db, p->pEList, iTable, pEList);
   substExprList(db, p->pGroupBy, iTable, pEList);
@@ -2434,6 +2437,12 @@ static void substSelect(
   substExpr(db, p->pHaving, iTable, pEList);
   substExpr(db, p->pWhere, iTable, pEList);
   substSelect(db, p->pPrior, iTable, pEList);
+  pSrc = p->pSrc;
+  if( pSrc ){
+    for(i=pSrc->nSrc, pItem=pSrc->a; i>0; i--, pItem++){
+      substSelect(db, pItem->pSelect, iTable, pEList);
+    }
+  }
 }
 #endif /* !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW) */
 
@@ -2718,17 +2727,31 @@ static int flattenSubquery(
     ** elements we are now copying in.
     */
     if( pSrc ){
+      Table *pTabToDel;
       pSubitem = &pSrc->a[iFrom];
       nSubSrc = pSubSrc->nSrc;
       jointype = pSubitem->jointype;
-      sqlite3DeleteTable(pSubitem->pTab);
       sqlite3DbFree(db, pSubitem->zDatabase);
       sqlite3DbFree(db, pSubitem->zName);
       sqlite3DbFree(db, pSubitem->zAlias);
-      pSubitem->pTab = 0;
       pSubitem->zDatabase = 0;
       pSubitem->zName = 0;
       pSubitem->zAlias = 0;
+
+      /* If the FROM element is a subquery, defer deleting the Table
+      ** object associated with that subquery until code generation is
+      ** complete, since there may still exist Expr.pTab entires that
+      ** refer to the subquery even after flattening.  Ticket #3346.
+      */
+      if( (pTabToDel = pSubitem->pTab)!=0 ){
+        if( pTabToDel->nRef==1 ){
+          pTabToDel->pNextZombie = pParse->pZombieTab;
+          pParse->pZombieTab = pTabToDel;
+        }else{
+          pTabToDel->nRef--;
+        }
+      }
+      pSubitem->pTab = 0;
     }
     if( nSubSrc!=1 || !pSrc ){
       int extra = nSubSrc - 1;

src/sqliteInt.h

@@ -11,7 +11,7 @@
 *************************************************************************
 ** Internal interface definitions for SQLite.
 **
-** @(#) $Id: sqliteInt.h,v 1.764 2008/08/29 18:42:30 rse Exp $
+** @(#) $Id: sqliteInt.h,v 1.765 2008/09/01 15:52:11 drh Exp $
 */
 #ifndef _SQLITEINT_H_
 #define _SQLITEINT_H_
@@ -983,6 +983,7 @@ struct Table {
   char **azModuleArg;  /* Text of all module args. [0] is module name */
 #endif
   Schema *pSchema;     /* Schema that contains this table */
+  Table *pNextZombie;  /* Next on the Parse.pZombieTab list */
 };
 
 /*
@@ -1701,6 +1702,7 @@ struct Parse {
   Table **apVtabLock;        /* Pointer to virtual tables needing locking */
 #endif
   int nHeight;            /* Expression tree height of current sub-select */
+  Table *pZombieTab;      /* List of Table objects to delete after code gen */
 };
 
 #ifdef SQLITE_OMIT_VIRTUALTABLE

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 1.151 2008/08/29 02:14:03 drh Exp $
+** $Id: tokenize.c,v 1.152 2008/09/01 15:52:11 drh Exp $
 */
 #include "sqliteInt.h"
 #include <ctype.h>
@@ -504,6 +504,11 @@ abort_parse:
   sqlite3DeleteTrigger(db, pParse->pNewTrigger);
   sqlite3DbFree(db, pParse->apVarExpr);
   sqlite3DbFree(db, pParse->aAlias);
+  while( pParse->pZombieTab ){
+    Table *p = pParse->pZombieTab;
+    pParse->pZombieTab = p->pNextZombie;
+    sqlite3DeleteTable(p);
+  }
   if( nErr>0 && (pParse->rc==SQLITE_OK || pParse->rc==SQLITE_DONE) ){
     pParse->rc = SQLITE_ERROR;
   }

test/capi2.test

@@ -11,7 +11,7 @@
 # This file implements regression tests for SQLite library.  The
 # focus of this script testing the callback-free C/C++ API.
 #
-# $Id: capi2.test,v 1.35 2008/01/16 17:46:38 drh Exp $
+# $Id: capi2.test,v 1.36 2008/09/01 15:52:11 drh Exp $
 #
 
 set testdir [file dirname $argv0]
@@ -722,6 +722,7 @@ ifcapable view&&subquery {
     check_origins {SELECT b, a FROM (SELECT col1 AS a, col2 AS b FROM view1)}
   } [list {main tab1 col2} {main tab1 col1}]
   do_test capi2-12.5 {
+breakpoint
     check_origins {SELECT (SELECT col2 FROM view1), (SELECT col1 FROM view1)}
   } [list {main tab1 col2} {main tab1 col1}]
   do_test capi2-12.6 {

test/tkt3346.test

@@ -0,0 +1,31 @@
+# 2008 September 1
+#
+# The author disclaims copyright to this source code.  In place of
+# a legal notice, here is a blessing:
+#
+#    May you do good and not evil.
+#    May you find forgiveness for yourself and forgive others.
+#    May you share freely, never taking more than you give.
+#
+#***********************************************************************
+#
+# This file implements regression tests for SQLite library.  The
+# focus of this file is testing the fix for ticket #3346
+#
+# $Id: tkt3346.test,v 1.1 2008/09/01 15:52:11 drh Exp $
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+
+do_test tkt3346-1.1 {
+  db eval {
+   CREATE TABLE t1(a,b);
+   INSERT INTO t1 VALUES(2,'bob');
+   INSERT INTO t1 VALUES(1,'alice');
+   INSERT INTO t1 VALUES(3,'claire');
+   SELECT *, ( SELECT y FROM (SELECT x.b='alice' AS y) )
+     FROM ( SELECT * FROM t1 ) AS x;
+  }
+} {2 bob 0 1 alice 1 3 claire 0}
+
+finish_test

test/where.test

@@ -1,4 +1,4 @@
-# 4 2001 September 15
+# 2001 September 15
 #
 # The author disclaims copyright to this source code.  In place of
 # a legal notice, here is a blessing:
@@ -11,7 +11,7 @@
 # This file implements regression tests for SQLite library.  The
 # focus of this file is testing the use of indices in WHERE clases.
 #
-# $Id: where.test,v 1.46 2008/07/15 00:27:35 drh Exp $
+# $Id: where.test,v 1.47 2008/09/01 15:52:11 drh Exp $
 
 set testdir [file dirname $argv0]
 source $testdir/tester.tcl