Fix for ticket #84: If the WHERE clause is too complex, issue an error message

and refuse to do the SELECT.  The cutoff is a WHERE clause with 100 terms. (CVS 650)

FossilOrigin-Name: c07e493b62125e85eaea36b6945f1e146e2792b8

manifest

@@ -1,5 +1,5 @@
-C Fix\sfor\sticket\s#88:\sA\stypo\sin\sthe\sdocumention\sof\sthe\s"sqlite"\sshell\scommand.\s(CVS\s649)
-D 2002-06-27T13:21:02
+C Fix\sfor\sticket\s#84:\sIf\sthe\sWHERE\sclause\sis\stoo\scomplex,\sissue\san\serror\smessage\nand\srefuse\sto\sdo\sthe\sSELECT.\s\sThe\scutoff\sis\sa\sWHERE\sclause\swith\s100\sterms.\s(CVS\s650)
+D 2002-06-28T01:02:38
 F Makefile.in 6291a33b87d2a395aafd7646ee1ed562c6f2c28c
 F Makefile.template 4e11752e0b5c7a043ca50af4296ec562857ba495
 F README a4c0ba11354ef6ba0776b400d057c59da47a4cc0
@@ -52,9 +52,9 @@ F src/tokenize.c ac4c46f190346b87da54ec3e2605d160af80c619
 F src/trigger.c d88ab4d68d68955c217b38fb6717e090fbbf54a4
 F src/update.c 6f6a4dcd71cd9ff730b7f12c83de5498cde4924f
 F src/util.c 876b259f9186e84b944b72e793dd3dad50e63e95
-F src/vdbe.c 2d9e418e45b75ac361e8e3ba96d84ce0a1ff9139
+F src/vdbe.c 0c7783ba52b1bd9e40331937c32d3aa3351ff4a3
 F src/vdbe.h a9292f2b5fcecef924fa255fb74609e9cbc776c2
-F src/where.c 913fa33977c8dddfc259d9b2c38504b475738c43
+F src/where.c e692b238fa0b45c159ab736da3fad2703800a0ca
 F test/all.test e4d3821eeba751829b419cd47814bd20af4286d1
 F test/bigrow.test 8ab252dba108f12ad64e337b0f2ff31a807ac578
 F test/btree.test bf326f546a666617367a7033fa2c07451bd4f8e1
@@ -77,7 +77,7 @@ F test/lock.test f1b55dc61632e99d241643cc8e7c03774f09f623
 F test/main.test c66b564554b770ee7fdbf6a66c0cd90329bc2c85
 F test/malloc.test 7ba32a9ebd3aeed52ae4aaa6d42ca37e444536fd
 F test/minmax.test 29bc5727c3e4c792d5c4745833dd4b505905819e
-F test/misc1.test 18c74cdfa6cc920f1c51827ccb23a442c62caefb
+F test/misc1.test 13584dda012d7d10b5163c2cecd60ab25496b987
 F test/misuse.test a3aa2b18a97e4c409a1fcaff5151a4dd804a0162
 F test/notnull.test b1f3e42fc475b0b5827b27b2e9b562081995ff30
 F test/null.test 5c2b57307e4b6178aae825eb65ddbee01e76b0fd
@@ -137,7 +137,7 @@ F www/speed.tcl da8afcc1d3ccc5696cfb388a68982bc3d9f7f00f
 F www/sqlite.tcl ae3dcfb077e53833b59d4fcc94d8a12c50a44098
 F www/tclsqlite.tcl 1db15abeb446aad0caf0b95b8b9579720e4ea331
 F www/vdbe.tcl 2013852c27a02a091d39a766bc87cff329f21218
-P 9ca6368525fe81fe9c78c6911f4d23009ce858d5
-R 64604f95a1ca21aa191d2c12711489ff
+P 16552a7a29450a23765f0f05a9f4058638eafd74
+R 0b306828319c3c6ac72442b55b9bb1d4
 U drh
-Z 124e1d748152c1b96bd4bcf09a107eb2
+Z cd2730365c5ef98d487b1c111506dfad

manifest.uuid

@@ -1 +1 @@
-16552a7a29450a23765f0f05a9f4058638eafd74
+c07e493b62125e85eaea36b6945f1e146e2792b8

src/vdbe.c

@@ -30,7 +30,7 @@
 ** But other routines are also provided to help in building up
 ** a program instruction by instruction.
 **
-** $Id: vdbe.c,v 1.161 2002/06/26 02:45:04 drh Exp $
+** $Id: vdbe.c,v 1.162 2002/06/28 01:02:38 drh Exp $
 */
 #include "sqliteInt.h"
 #include <ctype.h>
@@ -2845,6 +2845,8 @@ case OP_Commit: {
   if( rc==SQLITE_OK ){
     sqliteCommitInternalChanges(db);
   }else{
+    if( db->pBeTemp ) sqliteBtreeRollback(db->pBeTemp);
+    sqliteBtreeRollback(pBt);
     sqliteRollbackInternalChanges(db);
   }
   break;

src/where.c

@@ -13,7 +13,7 @@
 ** the WHERE clause of SQL statements.  Also found here are subroutines
 ** to generate VDBE code to evaluate expressions.
 **
-** $Id: where.c,v 1.56 2002/06/25 01:09:12 drh Exp $
+** $Id: where.c,v 1.57 2002/06/28 01:02:38 drh Exp $
 */
 #include "sqliteInt.h"
 
@@ -304,12 +304,28 @@ WhereInfo *sqliteWhereBegin(
   int iDirectEq[32];   /* Term of the form ROWID==X for the N-th table */
   int iDirectLt[32];   /* Term of the form ROWID<X or ROWID<=X */
   int iDirectGt[32];   /* Term of the form ROWID>X or ROWID>=X */
-  ExprInfo aExpr[50];  /* The WHERE clause is divided into these expressions */
+  ExprInfo aExpr[101]; /* The WHERE clause is divided into these expressions */
 
   /* pushKey is only allowed if there is a single table (as in an INSERT or
   ** UPDATE statement)
   */
   assert( pushKey==0 || pTabList->nSrc==1 );
+
+  /* Split the WHERE clause into separate subexpressions where each
+  ** subexpression is separated by an AND operator.  If the aExpr[]
+  ** array fills up, the last entry might point to an expression which
+  ** contains additional unfactored AND operators.
+  */
+  memset(aExpr, 0, sizeof(aExpr));
+  nExpr = exprSplit(ARRAYSIZE(aExpr), aExpr, pWhere);
+  if( nExpr==ARRAYSIZE(aExpr) ){
+    char zBuf[50];
+    sprintf(zBuf, "%d", ARRAYSIZE(aExpr)-1);
+    sqliteSetString(&pParse->zErrMsg, "WHERE clause too complex - no more "
+       "than ", zBuf, " terms allowed", 0);
+    pParse->nErr++;
+    return 0;
+  }
   
   /* Allocate space for aOrder[] */
   aOrder = sqliteMalloc( sizeof(int) * pTabList->nSrc );
@@ -337,16 +353,6 @@ WhereInfo *sqliteWhereBegin(
     pWhere = 0;
   }
 
-  /* Split the WHERE clause into as many as 32 separate subexpressions
-  ** where each subexpression is separated by an AND operator.  Any additional
-  ** subexpressions are attached in the aExpr[32] and will not enter
-  ** into the query optimizer computations.  32 is chosen as the cutoff
-  ** since that is the number of bits in an integer that we use for an
-  ** expression-used mask.  
-  */
-  memset(aExpr, 0, sizeof(aExpr));
-  nExpr = exprSplit(ARRAYSIZE(aExpr), aExpr, pWhere);
-
   /* Analyze all of the subexpressions.
   */
   for(i=0; i<nExpr; i++){

test/misc1.test

@@ -13,7 +13,7 @@
 # This file implements tests for miscellanous features that were
 # left out of other test files.
 #
-# $Id: misc1.test,v 1.9 2002/06/21 23:01:51 drh Exp $
+# $Id: misc1.test,v 1.10 2002/06/28 01:02:39 drh Exp $
 
 set testdir [file dirname $argv0]
 source $testdir/tester.tcl
@@ -258,4 +258,47 @@ do_test misc1-9.1 {
   }
 } {0 {a 12345678901234567890 b 12345678911234567890 c 12345678921234567890}}
 
+# A WHERE clause is not allowed to contain more than 99 terms.  Check to
+# make sure this limit is enforced.
+#
+do_test misc1-10.0 {
+  execsql {SELECT count(*) FROM manycol}
+} {9}
+do_test misc1-10.1 {
+  set ::where {WHERE x0>=0}
+  for {set i 1} {$i<=99} {incr i} {
+    append ::where " AND x$i<>0"
+  }
+  catchsql "SELECT count(*) FROM manycol $::where"
+} {0 9}
+do_test misc1-10.2 {
+  catchsql "SELECT count(*) FROM manycol $::where AND rowid>0"
+} {1 {WHERE clause too complex - no more than 100 terms allowed}}
+do_test misc1-10.3 {
+  regsub "x0>=0" $::where "x0=0" ::where
+  catchsql "DELETE FROM manycol $::where"
+} {0 {}}
+do_test misc1-10.4 {
+  execsql {SELECT count(*) FROM manycol}
+} {8}
+do_test misc1-10.5 {
+  catchsql "DELETE FROM manycol $::where AND rowid>0"
+} {1 {WHERE clause too complex - no more than 100 terms allowed}}
+do_test misc1-10.6 {
+  execsql {SELECT x1 FROM manycol WHERE x0=100}
+} {101}
+do_test misc1-10.7 {
+  regsub "x0=0" $::where "x0=100" ::where
+  catchsql "UPDATE manycol SET x1=x1+1 $::where"
+} {0 {}}
+do_test misc1-10.8 {
+  execsql {SELECT x1 FROM manycol WHERE x0=100}
+} {102}
+do_test misc1-10.9 {
+  catchsql "UPDATE manycol SET x1=x1+1 $::where AND rowid>0"
+} {1 {WHERE clause too complex - no more than 100 terms allowed}}
+do_test misc1-10.10 {
+  execsql {SELECT x1 FROM manycol WHERE x0=100}
+} {102}
+
 finish_test