From e9cdceafab9ccf7eb84d799733024299a01c8d54 Mon Sep 17 00:00:00 2001
From: drh <drh@noemail.net>
Date: Thu, 22 Jul 2010 22:40:03 +0000
Subject: [PATCH] Add evidence marks to the where.c source file.  Comment only
 - no code changes.

FossilOrigin-Name: f3f9e8e5bb90cc36e0d63a7289a8acf534c5fa2a
---
 manifest      | 24 +++++++++++++++++-------
 manifest.uuid |  2 +-
 src/where.c   | 32 ++++++++++++++++++++++++++++----
 3 files changed, 46 insertions(+), 12 deletions(-)

diff --git a/manifest b/manifest
index 9c7da7b2ce..70a6dcca86 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,8 @@
-C Make\sthe\ssqlite3_db_status()\sroutine\sthreadsafe.
-D 2010-07-22T17:55:40
+-----BEGIN PGP SIGNED MESSAGE-----
+Hash: SHA1
+
+C Add\sevidence\smarks\sto\sthe\swhere.c\ssource\sfile.\s\sComment\sonly\s-\sno\scode\schanges.
+D 2010-07-22T22:40:04
 F Makefile.arm-wince-mingw32ce-gcc fcd5e9cd67fe88836360bb4f9ef4cb7f8e2fb5a0
 F Makefile.in ec08dc838fd8110fe24c92e5130bcd91cbb1ff2e
 F Makefile.linux-gcc d53183f4aa6a9192d249731c90dbdffbd2c68654
@@ -230,7 +233,7 @@ F src/vtab.c a0f8a40274e4261696ef57aa806de2776ab72cda
 F src/wal.c 0925601f3299c2941a67c9cfff41ee710f70ca82
 F src/wal.h 906c85760598b18584921fe08008435aa4eeeeb2
 F src/walker.c 3112bb3afe1d85dc52317cb1d752055e9a781f8f
-F src/where.c 19a0f80a759ef288ed925e64944bbbbae3215abf
+F src/where.c 62262cee281c859ae136a40371f68a869b59ea1a
 F test/aggerror.test a867e273ef9e3d7919f03ef4f0e8c0d2767944f2
 F test/alias.test 4529fbc152f190268a15f9384a5651bbbabc9d87
 F test/all.test 6745008c144bd2956d58864d21f7b304689c1cce
@@ -838,7 +841,14 @@ F tool/speedtest2.tcl ee2149167303ba8e95af97873c575c3e0fab58ff
 F tool/speedtest8.c 2902c46588c40b55661e471d7a86e4dd71a18224
 F tool/speedtest8inst1.c 293327bc76823f473684d589a8160bde1f52c14e
 F tool/vdbe-compress.tcl d70ea6d8a19e3571d7ab8c9b75cba86d1173ff0f
-P 9f932655f9eb9fdab16d7deed98b7cad414e0ca6
-R f4b6bdde71d0ed3e7ea8f2e2fea940cb
-U dan
-Z 79b01e4fa7fd5fb80263b4c4dd7b3da4
+P 241f7bd190329fa02ca428651072a4a206132eab
+R 58c9336648eb3ce384b25cb1a31df81e
+U drh
+Z 05893823ee3052eca076f0070c9d2946
+-----BEGIN PGP SIGNATURE-----
+Version: GnuPG v1.4.6 (GNU/Linux)
+
+iD8DBQFMSMjIoxKgR168RlERAotrAJwKX5P9bHGJ1mEEtboK6UGGgyWioQCgi8M5
+Adn9/cSJE8bR6eO9+n8ekCg=
+=4n2n
+-----END PGP SIGNATURE-----
diff --git a/manifest.uuid b/manifest.uuid
index cd8da2c11e..76fb7d733e 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-241f7bd190329fa02ca428651072a4a206132eab
\ No newline at end of file
+f3f9e8e5bb90cc36e0d63a7289a8acf534c5fa2a
\ No newline at end of file
diff --git a/src/where.c b/src/where.c
index 547df68425..3e6189c57e 100644
--- a/src/where.c
+++ b/src/where.c
@@ -327,6 +327,7 @@ static void whereClauseClear(WhereClause *pWC){
 static int whereClauseInsert(WhereClause *pWC, Expr *p, u8 wtFlags){
   WhereTerm *pTerm;
   int idx;
+  testcase( wtFlags & TERM_VIRTUAL );  /* EV: R-00211-15100 */
   if( pWC->nTerm>=pWC->nSlot ){
     WhereTerm *pOld = pWC->a;
     sqlite3 *db = pWC->pParse->db;
@@ -472,6 +473,13 @@ static Bitmask exprSelectTableUsage(WhereMaskSet *pMaskSet, Select *pS){
 ** Return TRUE if the given operator is one of the operators that is
 ** allowed for an indexable WHERE clause term.  The allowed operators are
 ** "=", "<", ">", "<=", ">=", and "IN".
+**
+** IMPLEMENTATION-OF: R-59926-26393 To be usable by an index a term must be
+** of one of the following forms: column = expression column > expression
+** column >= expression column < expression column <= expression
+** expression = column expression > column expression >= column
+** expression < column expression <= column column IN
+** (expression-list) column IN (subquery) column IS NULL
 */
 static int allowedOp(int op){
   assert( TK_GT>TK_EQ && TK_GT<TK_GE );
@@ -1016,6 +1024,8 @@ static void exprAnalyzeOrTerm(
     /* At this point, okToChngToIN is true if original pTerm satisfies
     ** case 1.  In that case, construct a new virtual term that is 
     ** pTerm converted into an IN operator.
+    **
+    ** EV: R-00211-15100
     */
     if( okToChngToIN ){
       Expr *pDup;            /* A transient duplicate expression */
@@ -1247,7 +1257,8 @@ static void exprAnalyze(
         ** inequality.  To avoid this, make sure to also run the full
         ** LIKE on all candidate expressions by clearing the isComplete flag
         */
-        if( c=='A'-1 ) isComplete = 0;
+        if( c=='A'-1 ) isComplete = 0;   /* EV: R-64339-08207 */
+
 
         c = sqlite3UpperToLower[c];
       }
@@ -2879,6 +2890,9 @@ static void bestIndex(
 ** in the ON clause.  The term is disabled in (3) because it is not part
 ** of a LEFT OUTER JOIN.  In (1), the term is not disabled.
 **
+** IMPLEMENTATION-OF: R-24597-58655 No tests are done for terms that are
+** completely satisfied by indices.
+**
 ** Disabling a term causes that term to not be tested in the inner loop
 ** of the join.  Disabling is an optimization.  When terms are satisfied
 ** by indices, we disable them to prevent redundant tests in the inner
@@ -3090,6 +3104,7 @@ static int codeAllEqualityTerms(
     /* The following true for indices with redundant columns. 
     ** Ex: CREATE INDEX i1 ON t1(a,b,a); SELECT * FROM t1 WHERE a=0 AND b=0; */
     testcase( (pTerm->wtFlags & TERM_CODED)!=0 );
+    testcase( pTerm->wtFlags & TERM_VIRTUAL ); /* EV: R-30575-11662 */
     r1 = codeEqualityTerm(pParse, pTerm, pLevel, regBase+j);
     if( r1!=regBase+j ){
       if( nReg==1 ){
@@ -3233,6 +3248,7 @@ static Bitmask codeOneLoopStart(
     assert( pTerm->pExpr!=0 );
     assert( pTerm->leftCursor==iCur );
     assert( omitTable==0 );
+    testcase( pTerm->wtFlags & TERM_VIRTUAL ); /* EV: R-30575-11662 */
     iRowidReg = codeEqualityTerm(pParse, pTerm, pLevel, iReleaseReg);
     addrNxt = pLevel->addrNxt;
     sqlite3VdbeAddOp2(v, OP_MustBeInt, iRowidReg, addrNxt);
@@ -3273,6 +3289,7 @@ static Bitmask codeOneLoopStart(
       assert( TK_LT==TK_GT+2 );      /*  ... of the TK_xx values... */
       assert( TK_GE==TK_GT+3 );      /*  ... is correcct. */
 
+      testcase( pStart->wtFlags & TERM_VIRTUAL ); /* EV: R-30575-11662 */
       pX = pStart->pExpr;
       assert( pX!=0 );
       assert( pStart->leftCursor==iCur );
@@ -3290,6 +3307,7 @@ static Bitmask codeOneLoopStart(
       pX = pEnd->pExpr;
       assert( pX!=0 );
       assert( pEnd->leftCursor==iCur );
+      testcase( pEnd->wtFlags & TERM_VIRTUAL ); /* EV: R-30575-11662 */
       memEndValue = ++pParse->nMem;
       sqlite3ExprCode(pParse, pX->pRight, memEndValue);
       if( pX->op==TK_LT || pX->op==TK_GT ){
@@ -3457,6 +3475,7 @@ static Bitmask codeOneLoopStart(
         }
       }  
       nConstraint++;
+      testcase( pRangeStart->wtFlags & TERM_VIRTUAL ); /* EV: R-30575-11662 */
     }else if( isMinQuery ){
       sqlite3VdbeAddOp2(v, OP_Null, 0, regBase+nEq);
       nConstraint++;
@@ -3496,6 +3515,7 @@ static Bitmask codeOneLoopStart(
       }  
       codeApplyAffinity(pParse, regBase, nEq+1, zEndAff);
       nConstraint++;
+      testcase( pRangeEnd->wtFlags & TERM_VIRTUAL ); /* EV: R-30575-11662 */
     }
     sqlite3DbFree(pParse->db, zStartAff);
     sqlite3DbFree(pParse->db, zEndAff);
@@ -3702,11 +3722,15 @@ static Bitmask codeOneLoopStart(
 
   /* Insert code to test every subexpression that can be completely
   ** computed using the current set of tables.
+  **
+  ** IMPLEMENTATION-OF: R-49525-50935 Terms that cannot be satisfied through
+  ** the use of indices become tests that are evaluated against each row of
+  ** the relevant input tables.
   */
   k = 0;
   for(pTerm=pWC->a, j=pWC->nTerm; j>0; j--, pTerm++){
     Expr *pE;
-    testcase( pTerm->wtFlags & TERM_VIRTUAL );
+    testcase( pTerm->wtFlags & TERM_VIRTUAL ); /* IMP: R-30575-11662 */
     testcase( pTerm->wtFlags & TERM_CODED );
     if( pTerm->wtFlags & (TERM_VIRTUAL|TERM_CODED) ) continue;
     if( (pTerm->prereqAll & notReady)!=0 ){
@@ -3734,7 +3758,7 @@ static Bitmask codeOneLoopStart(
     VdbeComment((v, "record LEFT JOIN hit"));
     sqlite3ExprCacheClear(pParse);
     for(pTerm=pWC->a, j=0; j<pWC->nTerm; j++, pTerm++){
-      testcase( pTerm->wtFlags & TERM_VIRTUAL );
+      testcase( pTerm->wtFlags & TERM_VIRTUAL );  /* IMP: R-30575-11662 */
       testcase( pTerm->wtFlags & TERM_CODED );
       if( pTerm->wtFlags & (TERM_VIRTUAL|TERM_CODED) ) continue;
       if( (pTerm->prereqAll & notReady)!=0 ){
@@ -3952,7 +3976,7 @@ WhereInfo *sqlite3WhereBegin(
   initMaskSet(pMaskSet);
   whereClauseInit(pWC, pParse, pMaskSet);
   sqlite3ExprCodeConstants(pParse, pWhere);
-  whereSplit(pWC, pWhere, TK_AND);
+  whereSplit(pWC, pWhere, TK_AND);   /* IMP: R-15842-53296 */
     
   /* Special case: a WHERE clause that is constant.  Evaluate the
   ** expression and either jump over all of the code or fall thru.