From: drh <drh@noemail.net>
Date: Wed, 12 Sep 2007 15:41:01 +0000 (+0000)
Subject: In the query optimizer, make sure table dependencies from all terms
X-Git-Tag: version-3.6.10~1755
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=a430ae8e54bc0f61b3398f81139f188fcfda915a;p=thirdparty%2Fsqlite.git

In the query optimizer, make sure table dependencies from all terms
of a compound SELECT statement are recognized so that subqueries in
a WHERE clause are not evaluated too early.  Fix for ticket #2640. (CVS 4422)

FossilOrigin-Name: 9c9c2a1da2b6235b3b0541d1f55a02a1f350567f
---

diff --git a/manifest b/manifest
index 118ed4a850..98f7ef32db 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Add\sa\smissing\ssemi-colon\sto\sos_win.c.\sTicket\s#2642.\s(CVS\s4421)
-D 2007-09-12T14:09:23
+C In\sthe\squery\soptimizer,\smake\ssure\stable\sdependencies\sfrom\sall\sterms\nof\sa\scompound\sSELECT\sstatement\sare\srecognized\sso\sthat\ssubqueries\sin\na\sWHERE\sclause\sare\snot\sevaluated\stoo\searly.\s\sFix\sfor\sticket\s#2640.\s(CVS\s4422)
+D 2007-09-12T15:41:01
 F Makefile.in cbfb898945536a8f9ea8b897e1586dd1fdbcc5db
 F Makefile.linux-gcc 65241babba6faf1152bf86574477baab19190499
 F README 9c4e2d6706bdcc3efdd773ce752a8cdab4f90028
@@ -172,7 +172,7 @@ F src/vdbeblob.c 82f51cdf9b0c0af729732fde48c824e498c0a1ca
 F src/vdbefifo.c 334c838c8f42d61a94813d136019ee566b5dc2f6
 F src/vdbemem.c 246d434fa60bde6553490eb686adfd86adcd6712
 F src/vtab.c 6776605198e0b844391335f1b77e3595b3616331
-F src/where.c 4687a2a56bc0fe66ad457958ea9f72b6cae17426
+F src/where.c 1b3a67bba14cb19b44496090a66f58370b8c768d
 F tclinstaller.tcl 4356d9d94d2b5ed5e68f9f0c80c4df3048dd7617
 F test/aggerror.test a867e273ef9e3d7919f03ef4f0e8c0d2767944f2
 F test/all.test b59d1bd8b0c1d4a08b845e8af48fd43926f01f11
@@ -456,6 +456,7 @@ F test/tkt2339.test 7016415bda86af1406a27260ac46f44885617606
 F test/tkt2391.test ab7a11be7402da8b51a5be603425367aa0684567
 F test/tkt2409.test f130054aedff681883466ad04332bd3f7db51a02
 F test/tkt2450.test 77ed94863f2049c1420288ddfea2d41e5e0971d6
+F test/tkt2640.test c513e7992a602a87ef3a2cc9ca1cba4146924e9b
 F test/trace.test 75ffc1b992c780d054748a656e3e7fd674f18567
 F test/trans.test d132b8af1429a1e006bf4473de9a6e4c7f67a3f4
 F test/trigger1.test b361161cf20614024cc1e52ea0bdec250776b2ae
@@ -575,7 +576,7 @@ F www/tclsqlite.tcl 8be95ee6dba05eabcd27a9d91331c803f2ce2130
 F www/vdbe.tcl 87a31ace769f20d3627a64fa1fade7fed47b90d0
 F www/version3.tcl 890248cf7b70e60c383b0e84d77d5132b3ead42b
 F www/whentouse.tcl fc46eae081251c3c181bd79c5faef8195d7991a5
-P 4dbeb915b3138194abd5554b52003162235f9a5f
-R 02383b5025ac23032b71caa8921229ac
-U danielk1977
-Z 8ca913804fd51c8a1ac42ebd8d8ec287
+P c6ee5929e7d1f9b7c351f57ee8886f71ea0b6619
+R d30c1161749c146af96e8835cb148fe8
+U drh
+Z 7de72dd4fad27cd8d1629bca893a1041
diff --git a/manifest.uuid b/manifest.uuid
index dffb745686..623c5c09be 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-c6ee5929e7d1f9b7c351f57ee8886f71ea0b6619
\ No newline at end of file
+9c9c2a1da2b6235b3b0541d1f55a02a1f350567f
\ No newline at end of file
diff --git a/src/where.c b/src/where.c
index a9a3c7594b..126b0847c4 100644
--- a/src/where.c
+++ b/src/where.c
@@ -16,7 +16,7 @@
 ** so is applicable.  Because this module is responsible for selecting
 ** indices, you might also think of this module as the "query optimizer".
 **
-** $Id: where.c,v 1.259 2007/08/29 14:06:23 danielk1977 Exp $
+** $Id: where.c,v 1.260 2007/09/12 15:41:01 drh Exp $
 */
 #include "sqliteInt.h"
 
@@ -350,15 +350,14 @@ static Bitmask exprListTableUsage(ExprMaskSet *pMaskSet, ExprList *pList){
   return mask;
 }
 static Bitmask exprSelectTableUsage(ExprMaskSet *pMaskSet, Select *pS){
-  Bitmask mask;
-  if( pS==0 ){
-    mask = 0;
-  }else{
-    mask = exprListTableUsage(pMaskSet, pS->pEList);
+  Bitmask mask = 0;
+  while( pS ){
+    mask |= exprListTableUsage(pMaskSet, pS->pEList);
     mask |= exprListTableUsage(pMaskSet, pS->pGroupBy);
     mask |= exprListTableUsage(pMaskSet, pS->pOrderBy);
     mask |= exprTableUsage(pMaskSet, pS->pWhere);
     mask |= exprTableUsage(pMaskSet, pS->pHaving);
+    pS = pS->pPrior;
   }
   return mask;
 }
diff --git a/test/tkt2640.test b/test/tkt2640.test
new file mode 100644
index 0000000000..d2fa0e6092
--- /dev/null
+++ b/test/tkt2640.test
@@ -0,0 +1,119 @@
+# 2007 Sep 12
+#
+# 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 is to test that ticket #2640 has been fixed.
+#
+# $Id: tkt2640.test,v 1.1 2007/09/12 15:41:01 drh Exp $
+#
+
+# The problem in ticket #2640 was that the query optimizer was 
+# not recognizing all uses of tables within subqueries in the
+# WHERE clause.  If the subquery contained a compound SELECT,
+# then tables that were used by terms of the compound other than
+# the last term would not be recognized as dependencies.
+# So if one of the SELECT statements within a compound made
+# use of a table that occurs later in a join, the query
+# optimizer would not recognize this and would try to evaluate
+# the subquery too early, before that tables value had been
+# established.
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+
+do_test tkt2640-1.1 {
+  execsql {
+    CREATE TABLE persons(person_id, name);
+    INSERT INTO persons VALUES(1,'fred');
+    INSERT INTO persons VALUES(2,'barney');
+    INSERT INTO persons VALUES(3,'wilma');
+    INSERT INTO persons VALUES(4,'pebbles');
+    INSERT INTO persons VALUES(5,'bambam');
+    CREATE TABLE directors(person_id);
+    INSERT INTO directors VALUES(5);
+    INSERT INTO directors VALUES(3);
+    CREATE TABLE writers(person_id);
+    INSERT INTO writers VALUES(2);
+    INSERT INTO writers VALUES(3);
+    INSERT INTO writers VALUES(4);
+    SELECT DISTINCT p.name
+      FROM persons p, directors d
+     WHERE d.person_id=p.person_id
+       AND NOT EXISTS (
+             SELECT person_id FROM directors d1 WHERE d1.person_id=p.person_id
+             EXCEPT
+             SELECT person_id FROM writers w
+           );
+  }
+} {wilma}
+do_test tkt2640-1.2 {
+  execsql {
+    SELECT DISTINCT p.name
+      FROM persons p CROSS JOIN directors d
+     WHERE d.person_id=p.person_id
+       AND NOT EXISTS (
+             SELECT person_id FROM directors d1 WHERE d1.person_id=p.person_id
+             EXCEPT
+             SELECT person_id FROM writers w
+           );
+  }
+} {wilma}
+do_test tkt2640-1.3 {
+  execsql {
+    SELECT DISTINCT p.name
+      FROM directors d CROSS JOIN persons p
+     WHERE d.person_id=p.person_id
+       AND NOT EXISTS (
+             SELECT person_id FROM directors d1 WHERE d1.person_id=p.person_id
+             EXCEPT
+             SELECT person_id FROM writers w
+           );
+  }
+} {wilma}
+do_test tkt2640-1.4 {
+  execsql {
+    SELECT DISTINCT p.name
+      FROM persons p, directors d
+     WHERE d.person_id=p.person_id
+       AND NOT EXISTS (
+             SELECT person_id FROM directors d1 WHERE d1.person_id=d.person_id
+             EXCEPT
+             SELECT person_id FROM writers w
+           );
+  }
+} {wilma}
+do_test tkt2640-1.5 {
+  execsql {
+    SELECT DISTINCT p.name
+      FROM persons p CROSS JOIN directors d
+     WHERE d.person_id=p.person_id
+       AND NOT EXISTS (
+             SELECT person_id FROM directors d1 WHERE d1.person_id=d.person_id
+             EXCEPT
+             SELECT person_id FROM writers w
+           );
+  }
+} {wilma}
+do_test tkt2640-1.6 {
+  execsql {
+    SELECT DISTINCT p.name
+      FROM directors d CROSS JOIN persons p
+     WHERE d.person_id=p.person_id
+       AND NOT EXISTS (
+             SELECT person_id FROM directors d1 WHERE d1.person_id=d.person_id
+             EXCEPT
+             SELECT person_id FROM writers w
+           );
+  }
+} {wilma}
+
+
+
+finish_test