Fill out an initial implementation of the sqlite3ExprImpliesExpr() function.

FossilOrigin-Name: 8e07aa2ad5579aeb82174ce5bd432ddb9c058bc1

diff --git a/manifest b/manifest
index 1855b631ddf3045b88de8378bbbde9b8938fb881..aa3552550515ed5289bbf314110e15386dd05299 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Refactor\sinternal\sfunction\sname\ssqlite3VdbeGetValue()\sto\nsqlite3VdbeGetBoundValue().
-D 2013-08-01T12:21:58.409
+C Fill\sout\san\sinitial\simplementation\sof\sthe\ssqlite3ExprImpliesExpr()\sfunction.
+D 2013-08-01T13:04:46.842
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 5e41da95d92656a5004b03d3576e8b226858a28e
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -172,7 +172,7 @@ F src/complete.c dc1d136c0feee03c2f7550bafc0d29075e36deac
 F src/ctime.c 4262c227bc91cecc61ae37ed3a40f08069cfa267
 F src/date.c 067a81c9942c497aafd2c260e13add8a7d0c7dd4
 F src/delete.c 2317c814866d9aa71fea16b3faf4fdd4d6a49b94
-F src/expr.c 299f1de324676599b818e587b77e683978514461
+F src/expr.c 27a451dc75c8f2498199ddbd76e941f60fc31c73
 F src/fault.c 160a0c015b6c2629d3899ed2daf63d75754a32bb
 F src/fkey.c 914a6bbd987d857c41ac9d244efa6641f36faadb
 F src/func.c 5c50c1ea31fd864b0fe921fe1a8d4c55acd609ef
@@ -180,7 +180,7 @@ F src/global.c 5caf4deab621abb45b4c607aad1bd21c20aac759
 F src/hash.c ac3470bbf1ca4ae4e306a8ecb0fdf1731810ffe4
 F src/hash.h 8890a25af81fb85a9ad7790d32eedab4b994da22
 F src/hwtime.h d32741c8f4df852c7d959236615444e2b1063b08
-F src/insert.c b09e0aa7513aeda56b595126fb66f0580237f0ff
+F src/insert.c a66bcdc956145369c1a876709f47f69476973e15
 F src/journal.c b4124532212b6952f42eb2c12fa3c25701d8ba8d
 F src/legacy.c 0df0b1550b9cc1f58229644735e317ac89131f12
 F src/lempar.c cdf0a000315332fc9b50b62f3b5e22e080a0952b
@@ -214,14 +214,14 @@ F src/pragma.c aca37128da044cc4e41e1cea49a5e3cf6159df43
 F src/prepare.c fa6988589f39af8504a61731614cd4f6ae71554f
 F src/printf.c 41c49dac366a3a411190001a8ab495fa8887974e
 F src/random.c cd4a67b3953b88019f8cd4ccd81394a8ddfaba50
-F src/resolve.c ada80e8df5d4ab0a21cf65ec5be8ba3b826e2b6f
+F src/resolve.c 8b3c7a439cc6ba242e45566284adb72fa770b7c8
 F src/rowset.c 64655f1a627c9c212d9ab497899e7424a34222e0
-F src/select.c 91b62654caf8dfe292fb8882715e575d34ad3874
+F src/select.c 20369c82dc38eb4a77b458c8f6e353ef550580c9
 F src/shell.c 52f975eae87c8338c4dfbf4c2842d2a0971f01fd
 F src/sqlite.h.in d6a7523d6795317aac574fccc67d9df25253771c
 F src/sqlite3.rc fea433eb0a59f4c9393c8e6d76a6e2596b1fe0c0
 F src/sqlite3ext.h 886f5a34de171002ad46fae8c36a7d8051c190fc
-F src/sqliteInt.h b39d566354613e781d49ffe8d3ee58baa4f7b4f5
+F src/sqliteInt.h 7c6ad474ce49ed18393c027be65c9532b7c9168f
 F src/sqliteLimit.h 164b0e6749d31e0daa1a4589a169d31c0dec7b3d
 F src/status.c 7ac05a5c7017d0b9f0b4bcd701228b784f987158
 F src/table.c 2cd62736f845d82200acfa1287e33feb3c15d62e
@@ -1104,7 +1104,7 @@ F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh fbc018d67fd7395f440c28f33ef0f94420226381
 F tool/wherecosttest.c f407dc4c79786982a475261866a161cd007947ae
 F tool/win/sqlite.vsix 97894c2790eda7b5bce3cc79cb2a8ec2fde9b3ac
-P 60353124f4e965393ecd864019bdbca1999fb69e
-R bb451065c1214431469ba3f19aa1b916
+P 81834c3023876487a1188390aae850cf71683701
+R 97f0c54b3f7128423bcbfe2828fbdcb2
 U drh
-Z b1d702840c58e4dca1711593d0bbaf8a
+Z 2652ffb0448810ae6b88d2be09f88047

diff --git a/manifest.uuid b/manifest.uuid
index a0035d8ae78cd776eaf6e9c6ac0f2c22109d9c7e..021a48357088c58ee76b5657e5b920f9bdfc00bb 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-81834c3023876487a1188390aae850cf71683701
\ No newline at end of file
+8e07aa2ad5579aeb82174ce5bd432ddb9c058bc1
\ No newline at end of file

diff --git a/src/expr.c b/src/expr.c
index 96c05dc3ae3e68ab1d7c613a452d31dc7e32cf66..6fa34443a3767da7771250d02e89fa6ca6e7dcfc 100644 (file)
--- a/src/expr.c
+++ b/src/expr.c
@@ -3798,6 +3798,9 @@ void sqlite3ExprIfFalse(Parse *pParse, Expr *pExpr, int dest, int jumpIfNull){
 ** by a COLLATE operator at the top level.  Return 2 if there are differences
 ** other than the top-level COLLATE operator.
 **
+** If any subelement of pB has Expr.iTable==(-1) then it is allowed
+** to compare equal to an equivalent element in pA with Expr.iTable==iTab.
+**
 ** Sometimes this routine will return 2 even if the two expressions
 ** really are equivalent.  If we cannot prove that the expressions are
 ** identical, we return 2 just to be safe.  So if this routine
@@ -3808,7 +3811,7 @@ void sqlite3ExprIfFalse(Parse *pParse, Expr *pExpr, int dest, int jumpIfNull){
 ** just might result in some slightly slower code.  But returning
 ** an incorrect 0 or 1 could lead to a malfunction.
 */
-int sqlite3ExprCompare(Expr *pA, Expr *pB){
+int sqlite3ExprCompare(Expr *pA, Expr *pB, int iTab){
   if( pA==0||pB==0 ){
     return pB==pA ? 0 : 2;
   }
@@ -3819,18 +3822,19 @@ int sqlite3ExprCompare(Expr *pA, Expr *pB){
   }
   if( (pA->flags & EP_Distinct)!=(pB->flags & EP_Distinct) ) return 2;
   if( pA->op!=pB->op ){
-    if( pA->op==TK_COLLATE && sqlite3ExprCompare(pA->pLeft, pB)<2 ){
+    if( pA->op==TK_COLLATE && sqlite3ExprCompare(pA->pLeft, pB, iTab)<2 ){
       return 1;
     }
-    if( pB->op==TK_COLLATE && sqlite3ExprCompare(pA, pB->pLeft)<2 ){
+    if( pB->op==TK_COLLATE && sqlite3ExprCompare(pA, pB->pLeft, iTab)<2 ){
       return 1;
     }
     return 2;
   }
-  if( sqlite3ExprCompare(pA->pLeft, pB->pLeft) ) return 2;
-  if( sqlite3ExprCompare(pA->pRight, pB->pRight) ) return 2;
-  if( sqlite3ExprListCompare(pA->x.pList, pB->x.pList) ) return 2;
-  if( pA->iTable!=pB->iTable || pA->iColumn!=pB->iColumn ) return 2;
+  if( sqlite3ExprCompare(pA->pLeft, pB->pLeft, iTab) ) return 2;
+  if( sqlite3ExprCompare(pA->pRight, pB->pRight, iTab) ) return 2;
+  if( sqlite3ExprListCompare(pA->x.pList, pB->x.pList, iTab) ) return 2;
+  if( pA->iColumn!=pB->iColumn ) return 2;
+  if( pA->iTable!=pB->iTable && (pA->iTable!=iTab || pB->iTable>=0) ) return 2;
   if( ExprHasProperty(pA, EP_IntValue) ){
     if( !ExprHasProperty(pB, EP_IntValue) || pA->u.iValue!=pB->u.iValue ){
       return 2;
@@ -3848,6 +3852,9 @@ int sqlite3ExprCompare(Expr *pA, Expr *pB){
 ** Compare two ExprList objects.  Return 0 if they are identical and 
 ** non-zero if they differ in any way.
 **
+** If any subelement of pB has Expr.iTable==(-1) then it is allowed
+** to compare equal to an equivalent element in pA with Expr.iTable==iTab.
+**
 ** This routine might return non-zero for equivalent ExprLists.  The
 ** only consequence will be disabled optimizations.  But this routine
 ** must never return 0 if the two ExprList objects are different, or
@@ -3856,7 +3863,7 @@ int sqlite3ExprCompare(Expr *pA, Expr *pB){
 ** Two NULL pointers are considered to be the same.  But a NULL pointer
 ** always differs from a non-NULL pointer.
 */
-int sqlite3ExprListCompare(ExprList *pA, ExprList *pB){
+int sqlite3ExprListCompare(ExprList *pA, ExprList *pB, int iTab){
   int i;
   if( pA==0 && pB==0 ) return 0;
   if( pA==0 || pB==0 ) return 1;
@@ -3865,7 +3872,7 @@ int sqlite3ExprListCompare(ExprList *pA, ExprList *pB){
     Expr *pExprA = pA->a[i].pExpr;
     Expr *pExprB = pB->a[i].pExpr;
     if( pA->a[i].sortOrder!=pB->a[i].sortOrder ) return 1;
-    if( sqlite3ExprCompare(pExprA, pExprB) ) return 1;
+    if( sqlite3ExprCompare(pExprA, pExprB, iTab) ) return 1;
   }
   return 0;
 }
@@ -3875,9 +3882,13 @@ int sqlite3ExprListCompare(ExprList *pA, ExprList *pB){
 ** true.  Return false if we cannot complete the proof or if pE2 might
 ** be false.  Examples:
 **
-**     pE1: x==5      pE2: x>0              Result: true
-**     pE1: x>0       pE2: x==5             Result: false
-**     pE1: x!=123    pE2: x IS NOT NULL    Result: true
+**     pE1: x==5       pE2: x==5             Result: true
+**     pE1: x>0        pE2: x==5             Result: false
+**     pE1: x=21       pE2: x=21 OR y=43     Result: true
+**     pE1: x!=123     pE2: x IS NOT NULL    Result: true
+**     pE1: x!=?1      pE2: x IS NOT NULL    Result: true
+**     pE1: x IS NULL  pE2: x IS NOT NULL    Result: false
+**     pE1: x IS ?2    pE2: x IS NOT NULL    Reuslt: false
 **
 ** When comparing TK_COLUMN nodes between pE1 and pE2, if pE2 has
 ** Expr.iTable<0 then assume a table number given by iTab.
@@ -3887,7 +3898,22 @@ int sqlite3ExprListCompare(ExprList *pA, ExprList *pB){
 ** it will always give the correct answer and is hence always safe.
 */
 int sqlite3ExprImpliesExpr(Expr *pE1, Expr *pE2, int iTab){
-  return 0;  /* FIXME: this needs to be worked out */
+  if( sqlite3ExprCompare(pE1, pE2, iTab)==0 ){
+    return 1;
+  }
+  if( pE2->op==TK_OR
+   && (sqlite3ExprImpliesExpr(pE1, pE2->pLeft, iTab)
+             || sqlite3ExprImpliesExpr(pE1, pE2->pRight, iTab) )
+  ){
+    return 1;
+  }
+  if( pE2->op==TK_NOTNULL
+   && sqlite3ExprCompare(pE1->pLeft, pE2->pLeft, iTab)==0
+   && (pE1->op!=TK_ISNULL && pE1->op!=TK_IS)
+  ){
+    return 1;
+  }
+  return 0;
 }
 
 /*
@@ -4070,7 +4096,7 @@ static int analyzeAggregate(Walker *pWalker, Expr *pExpr){
         */
         struct AggInfo_func *pItem = pAggInfo->aFunc;
         for(i=0; i<pAggInfo->nFunc; i++, pItem++){
-          if( sqlite3ExprCompare(pItem->pExpr, pExpr)==0 ){
+          if( sqlite3ExprCompare(pItem->pExpr, pExpr, -1)==0 ){
             break;
           }
         }

diff --git a/src/insert.c b/src/insert.c
index 54821f18b7b8e14d19d71a811724c9aed6bc4afa..1c2cabb938b56a16ffbbc8a821180af5a4173a36 100644 (file)
--- a/src/insert.c
+++ b/src/insert.c
@@ -1648,7 +1648,7 @@ static int xferCompatibleIndex(Index *pDest, Index *pSrc){
       return 0;   /* Different collating sequences */
     }
   }
-  if( sqlite3ExprCompare(pSrc->pPartIdxWhere, pDest->pPartIdxWhere) ){
+  if( sqlite3ExprCompare(pSrc->pPartIdxWhere, pDest->pPartIdxWhere, -1) ){
     return 0;     /* Different WHERE clauses */
   }
 
@@ -1806,7 +1806,7 @@ static int xferOptimization(
     }
   }
 #ifndef SQLITE_OMIT_CHECK
-  if( pDest->pCheck && sqlite3ExprListCompare(pSrc->pCheck, pDest->pCheck) ){
+  if( pDest->pCheck && sqlite3ExprListCompare(pSrc->pCheck,pDest->pCheck,-1) ){
     return 0;   /* Tables have different CHECK constraints.  Ticket #2252 */
   }
 #endif

diff --git a/src/resolve.c b/src/resolve.c
index 239e0eb2a05e0d846e37a646e097f9915adfc87f..f288ed930c1cf1b2df7fe6021874f4c95398669f 100644 (file)
--- a/src/resolve.c
+++ b/src/resolve.c
@@ -825,7 +825,7 @@ static int resolveOrderByTermToExprList(
   ** result-set entry.
   */
   for(i=0; i<pEList->nExpr; i++){
-    if( sqlite3ExprCompare(pEList->a[i].pExpr, pE)<2 ){
+    if( sqlite3ExprCompare(pEList->a[i].pExpr, pE, -1)<2 ){
       return i+1;
     }
   }
@@ -1053,7 +1053,7 @@ static int resolveOrderGroupBy(
       return 1;
     }
     for(j=0; j<pSelect->pEList->nExpr; j++){
-      if( sqlite3ExprCompare(pE, pSelect->pEList->a[j].pExpr)==0 ){
+      if( sqlite3ExprCompare(pE, pSelect->pEList->a[j].pExpr, -1)==0 ){
         pItem->iOrderByCol = j+1;
       }
     }

diff --git a/src/select.c b/src/select.c
index fa35f45871d70b853dcfa901ccecf65e9471ee55..014feca8f295940d97c6bd2e78ebdd6e0a5ba747 100644 (file)
--- a/src/select.c
+++ b/src/select.c
@@ -4177,7 +4177,7 @@ int sqlite3Select(
   ** Use the SQLITE_GroupByOrder flag with SQLITE_TESTCTRL_OPTIMIZER
   ** to disable this optimization for testing purposes.
   */
-  if( sqlite3ExprListCompare(p->pGroupBy, pOrderBy)==0
+  if( sqlite3ExprListCompare(p->pGroupBy, pOrderBy, -1)==0
          && OptimizationEnabled(db, SQLITE_GroupByOrder) ){
     pOrderBy = 0;
   }
@@ -4198,7 +4198,7 @@ int sqlite3Select(
   ** BY and DISTINCT, and an index or separate temp-table for the other.
   */
   if( (p->selFlags & (SF_Distinct|SF_Aggregate))==SF_Distinct 
-   && sqlite3ExprListCompare(pOrderBy, p->pEList)==0
+   && sqlite3ExprListCompare(pOrderBy, p->pEList, -1)==0
   ){
     p->selFlags &= ~SF_Distinct;
     p->pGroupBy = sqlite3ExprListDup(db, p->pEList, 0);

diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 21e32ff7b3860910bd27e40d13f14ddcf01850ea..291957db9e693215dc1e48f199208d6d19692c0b 100644 (file)
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -2834,8 +2834,8 @@ void sqlite3UnlinkAndDeleteIndex(sqlite3*,int,const char*);
 void sqlite3Vacuum(Parse*);
 int sqlite3RunVacuum(char**, sqlite3*);
 char *sqlite3NameFromToken(sqlite3*, Token*);
-int sqlite3ExprCompare(Expr*, Expr*);
-int sqlite3ExprListCompare(ExprList*, ExprList*);
+int sqlite3ExprCompare(Expr*, Expr*, int);
+int sqlite3ExprListCompare(ExprList*, ExprList*, int);
 int sqlite3ExprImpliesExpr(Expr*, Expr*, int);
 void sqlite3ExprAnalyzeAggregates(NameContext*, Expr*);
 void sqlite3ExprAnalyzeAggList(NameContext*,ExprList*);