Avoid unnecessary collating sequence and affinity restrictions on the use

of transitivity.  Add test cases to show that the restrictions are not 
needed.

FossilOrigin-Name: 56549f45666b53876012df5c2bdf813474e10925

manifest

@@ -1,5 +1,5 @@
-C Make\smore\saggressive\suse\sof\stransitivity\sin\soptimizing\squeries.\s\sAdd\sa\stest\ncase.
+C Avoid\sunnecessary\scollating\ssequence\sand\saffinity\srestrictions\son\sthe\suse\nof\stransitivity.\s\sAdd\stest\scases\sto\sshow\sthat\sthe\srestrictions\sare\snot\s\nneeded.
-D 2013-01-17T15:05:17.153
+D 2013-01-17T16:18:55.615
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in a48faa9e7dd7d556d84f5456eabe5825dd8a6282
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -252,7 +252,7 @@ F src/vtab.c b05e5f1f4902461ba9f5fc49bb7eb7c3a0741a83
 F src/wal.c f5c7b5027d0ed0e9bc9afeb4a3a8dfea762ec7d2
 F src/wal.h 29c197540b19044e6cd73487017e5e47a1d3dac6
 F src/walker.c 3d75ba73de15e0f8cd0737643badbeb0e002f07b
-F src/where.c 701c32fecbcf44d749a8fdacb887ffdcec21a3e5
+F src/where.c 79c257691c5cbe92fae9dc35465392cbd11c3e31
 F test/8_3_names.test 631ea964a3edb091cf73c3b540f6bcfdb36ce823
 F test/aggerror.test a867e273ef9e3d7919f03ef4f0e8c0d2767944f2
 F test/aggnested.test 45c0201e28045ad38a530b5a144b73cd4aa2cfd6
@@ -896,6 +896,7 @@ F test/trace2.test c1dc104a8d11a347c870cfea6235e3fc6f6cb06d
 F test/trans.test 6e1b4c6a42dba31bd65f8fa5e61a2708e08ddde6
 F test/trans2.test d5337e61de45e66b1fcbf9db833fa8c82e624b22
 F test/trans3.test 373ac5183cc56be69f48ae44090e7f672939f732
+F test/transitive1.test d04aa9023e425d6f2d4aa61dd81ee9e102f89062
 F test/trigger1.test 30f343f91586765874a28ad539c06f5a5f049931
 F test/trigger2.test 834187beafd1db383af0c659cfa49b0576832816
 F test/trigger3.test d2c60d8be271c355d61727411e753181e877230a
@@ -1033,7 +1034,7 @@ F tool/vdbe-compress.tcl f12c884766bd14277f4fcedcae07078011717381
 F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh fbc018d67fd7395f440c28f33ef0f94420226381
 F tool/win/sqlite.vsix 97894c2790eda7b5bce3cc79cb2a8ec2fde9b3ac
-P fe152f8b048c9a18f99fa6096ff0e68dd630c318
+P d96762841a461e192fb2f317d684d000376350dd
-R f7b812e14ccd12b59aae7b48f0da1945
+R da60dbccb0041de3b6506adfaa629abe
 U drh
-Z eaf427dd060ebdbe2c55df9e5c68a5b1
+Z 92f034648a2e7d96254ca815101088e3

manifest.uuid

@@ -1 +1 @@
-d96762841a461e192fb2f317d684d000376350dd
+56549f45666b53876012df5c2bdf813474e10925

src/where.c

@@ -687,7 +687,9 @@ static WhereTerm *findTerm(
               pX = pTerm->pExpr;
               pParse = pWC->pParse;
               idxaff = pIdx->pTable->aCol[iOrigCol].affinity;
-              if( !sqlite3IndexAffinityOk(pX, idxaff) ) continue;
+              if( !sqlite3IndexAffinityOk(pX, idxaff) ){
+                continue;
+              }
       
               /* Figure out the collation sequence required from an index for
               ** it to be useful for optimising expression pX. Store this
@@ -700,7 +702,9 @@ static WhereTerm *findTerm(
               for(j=0; pIdx->aiColumn[j]!=iOrigCol; j++){
                 if( NEVER(j>=pIdx->nColumn) ) return 0;
               }
-              if( sqlite3StrICmp(pColl->zName, pIdx->azColl[j]) ) continue;
+              if( sqlite3StrICmp(pColl->zName, pIdx->azColl[j]) ){
+                continue;
+              }
             }
             pResult = pTerm;
             if( pTerm->prereqRight==0 ) goto findTerm_success;
@@ -1196,32 +1200,6 @@ static void exprAnalyzeOrTerm(
 }
 #endif /* !SQLITE_OMIT_OR_OPTIMIZATION && !SQLITE_OMIT_SUBQUERY */
 
-/*
-** Check to see if pExpr is an expression of the form A==B where both
-** A and B are columns with the same affinity and collating sequence.
-** If A and B are equivalent, return true.
-*/
-static int isEquivalenceExpr(Parse *pParse, Expr *pExpr){
-  const CollSeq *pCLeft, *pCRight;
-  if( pExpr->op!=TK_EQ ) return 0;
-  if( ExprHasProperty(pExpr, EP_FromJoin) ){
-    return 0;
-  }
-  assert( sqlite3ExprSkipCollate(pExpr->pRight)->op==TK_COLUMN );
-  assert( sqlite3ExprSkipCollate(pExpr->pLeft)->op==TK_COLUMN );
-  if( sqlite3ExprAffinity(pExpr->pLeft)!=sqlite3ExprAffinity(pExpr->pRight) ){
-    return 0;
-  }
-  pCLeft = sqlite3ExprCollSeq(pParse, pExpr->pLeft);
-  if( pCLeft ){
-    pCRight = sqlite3ExprCollSeq(pParse, pExpr->pRight);
-    if( pCRight && pCRight!=pCLeft ){
-      return 0;
-    }
-  }
-  return 1;
-}
-
 /*
 ** The input to this routine is an WhereTerm structure with only the
 ** "pExpr" field filled in.  The job of this routine is to analyze the
@@ -1317,7 +1295,7 @@ static void exprAnalyze(
         pTerm = &pWC->a[idxTerm];
         pTerm->nChild = 1;
         pTerm->wtFlags |= TERM_COPIED;
-        if( isEquivalenceExpr(pParse, pExpr) ){
+        if( pExpr->op==TK_EQ && !ExprHasProperty(pExpr, EP_FromJoin) ){
           pTerm->eOperator |= WO_EQUIV;
           eExtraOp = WO_EQUIV;
         }

test/transitive1.test

@@ -0,0 +1,50 @@
+# 2013 April 17
+#
+# 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 script is testing of transitive WHERE clause constraints
+#
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+
+do_execsql_test transitive1-100 {
+  CREATE TABLE t1(a TEXT, b TEXT, c TEXT COLLATE NOCASE);
+  INSERT INTO t1 VALUES('abc','abc','Abc');
+  INSERT INTO t1 VALUES('def','def','def');
+  INSERT INTO t1 VALUES('ghi','ghi','GHI');
+  CREATE INDEX t1a1 ON t1(a);
+  CREATE INDEX t1a2 ON t1(a COLLATE nocase);
+
+  SELECT * FROM t1 WHERE a=b AND c=b AND c='DEF';
+} {def def def}
+do_execsql_test transitive1-110 {
+  SELECT * FROM t1 WHERE a=b AND c=b AND c>='DEF' ORDER BY +a;
+} {def def def ghi ghi GHI}
+do_execsql_test transitive1-120 {
+  SELECT * FROM t1 WHERE a=b AND c=b AND c<='DEF' ORDER BY +a;
+} {abc abc Abc def def def}
+
+do_execsql_test transitive1-200 {
+  CREATE TABLE t2(a INTEGER, b INTEGER, c TEXT);
+  INSERT INTO t2 VALUES(100,100,100);
+  INSERT INTO t2 VALUES(20,20,20);
+  INSERT INTO t2 VALUES(3,3,3);
+
+  SELECT * FROM t2 WHERE a=b AND c=b AND c=20;
+} {20 20 20}
+do_execsql_test transitive1-210 {
+  SELECT * FROM t2 WHERE a=b AND c=b AND c>=20 ORDER BY +a;
+} {3 3 3 20 20 20}
+do_execsql_test transitive1-220 {
+  SELECT * FROM t2 WHERE a=b AND c=b AND c<=20 ORDER BY +a;
+} {20 20 20 100 100 100}
+
+finish_test