Improvements and simplifications to the equality seek logic. Tests are

adjusted so that they all pass now.

FossilOrigin-Name: 997ce6c90b454c03cc2ef6934752ee8dd2e520e3

manifest

@@ -1,5 +1,5 @@
-C The\stop\sof\san\sindex\sequality\sloop\snormally\sstarts\swith\sOP_SeekGE\sand\sOP_IdxGT.\nThis\scheck-in\sadds\sa\sflag\sto\sOP_SeekGE\ssuch\sthat\sit\sfails\simmediately\sif\nthe\skey\sis\snot\sequal,\sthen\sjumps\sover\sthe\sOP_IdxGT,\ssaving\sa\scall\sto\sthe\skey\ncomparison\sfunctions.\s\sConsider\sthis\scheck-in\sa\sproof-of-concept.\s\sIt\sneeds\s\nimprovement\sbefore\sgoing\son\strunk.\s\sSome\stests\sfail,\sbut\sonly\sbecause\sthey\nnew\suse\sfewer\skey\scomparisons\sthan\sexpected\s(which\sis\sa\sgood\sthing!).
-D 2015-11-05T20:25:09.480
+C Improvements\sand\ssimplifications\sto\sthe\sequality\sseek\slogic.\s\sTests\sare\nadjusted\sso\sthat\sthey\sall\spass\snow.
+D 2015-11-05T22:30:54.990
 F Makefile.in 3a705bb4bd12e194212ddbdbf068310d17153cdb
 F Makefile.linux-gcc 7bc79876b875010e8c8f9502eb935ca92aa3c434
 F Makefile.msc 702d3e98f3afc6587a78481257f3c4c900efc3a4
@@ -282,8 +282,8 @@ F src/auth.c b56c78ebe40a2110fd361379f7e8162d23f92240
 F src/backup.c 2869a76c03eb393ee795416e2387005553df72bc
 F src/bitvec.c d1f21d7d91690747881f03940584f4cc548c9d3d
 F src/btmutex.c 45a968cc85afed9b5e6cf55bf1f42f8d18107f79
-F src/btree.c 233c1536927b12d820cb0a19c657c59837f9334f
-F src/btree.h b512723e4f27d7ba16b4b985cdecdb82c0f6d0c0
+F src/btree.c 9e5d713bf54be8bfcae9b60210173dd53570f56d
+F src/btree.h 1b8bf2818b5e256c25a5e09126720113b1d783da
 F src/btreeInt.h 3ab435ed27adea54d040584b0bcc488ee7db1e38
 F src/build.c ca574d33ffb1763cfd2979383f4d507095bfbe19
 F src/callback.c 7b44ce59674338ad48b0e84e7b72f935ea4f68b0
@@ -345,7 +345,7 @@ F src/shell.c d25df04168d6ba5a4fa05bdbf859df667f9eb621
 F src/sqlite.h.in 3cfc86c55e57c63d86b9e1e92869e2bfb162ca8e
 F src/sqlite3.rc 992c9f5fb8285ae285d6be28240a7e8d3a7f2bad
 F src/sqlite3ext.h 4b66e3e3435da4b4c8c83696d0349f0c503b3924
-F src/sqliteInt.h 8769e43c68421bdd6b4b830290965c9303056c4f
+F src/sqliteInt.h 12ff325b433c4ded39995b74b01b78aacc19805a
 F src/sqliteLimit.h 216557999cb45f2e3578ed53ebefe228d779cb46
 F src/status.c 70912d7be68e9e2dbc4010c93d344af61d4c59ba
 F src/table.c 51b46b2a62d1b3a959633d593b89bab5e2c9155e
@@ -403,7 +403,7 @@ F src/update.c 40e51cd0883cb5bfd6abb7d8a7cd8aa47fab2945
 F src/utf.c fc6b889ba0779b7722634cdeaa25f1930d93820c
 F src/util.c fc612367108b74573c5fd13a85d0a23027f438bd
 F src/vacuum.c 2ddd5cad2a7b9cef7f9e431b8c7771634c6b1701
-F src/vdbe.c 1f9ef1ef7e48e1d5268036a18b7c9b5cded49879
+F src/vdbe.c a9b0ec9f8df86a805d593b625d1f21a8e71dcda5
 F src/vdbe.h efb7a8c1459e31f3ea4377824c6a7e4cb5068637
 F src/vdbeInt.h 33403622c6a8feaaac5f0f3f17f5d1bf6df42286
 F src/vdbeapi.c 020681b943e77766b32ae1cddf86d7831b7374ca
@@ -419,7 +419,7 @@ F src/wal.h df01efe09c5cb8c8e391ff1715cca294f89668a4
 F src/walker.c 2e14d17f592d176b6dc879c33fbdec4fbccaa2ba
 F src/where.c 6aceb72cc58dc06922a9e1604d559c8ca4c3e728
 F src/whereInt.h 7892bb54cf9ca0ae5c7e6094491b94c9286dc647
-F src/wherecode.c b45fe3878b0ea4962784d3072498ff63b233d958
+F src/wherecode.c 4c96182e7b25e4be54008dee2da5b9c2f8480b9b
 F src/whereexpr.c e63244ca06c503e5f3c5b7f3c9aea0db826089ed
 F test/8_3_names.test ebbb5cd36741350040fd28b432ceadf495be25b2
 F test/affinity2.test a6d901b436328bd67a79b41bb0ac2663918fe3bd
@@ -519,7 +519,7 @@ F test/coalesce.test cee0dccb9fbd2d494b77234bccf9dc6c6786eb91
 F test/collate1.test 08c18e7512a5a32c97938854263fa15362eeb846
 F test/collate2.test 9aaa410a00734e48bcb27f3872617d6f69b2a621
 F test/collate3.test 89defc49983ddfbf0a0555aca8c0521a676f56a5
-F test/collate4.test f04d5168685f2eef637ecfa2d4ddf8ec0d600177
+F test/collate4.test c953715fb498b87163e3e73dd94356bff1f317bd
 F test/collate5.test 65d928034d30d2d263a80f6359f7549ee1598ec6
 F test/collate6.test 8be65a182abaac8011a622131486dafb8076e907
 F test/collate7.test 8ec29d98f3ee4ccebce6e16ce3863fb6b8c7b868
@@ -1301,10 +1301,10 @@ F test/walro.test 34422d1d95aaff0388f0791ec20edb34e2a3ed57
 F test/walshared.test 0befc811dcf0b287efae21612304d15576e35417
 F test/walslow.test e7be6d9888f83aa5d3d3c7c08aa9b5c28b93609a
 F test/walthread.test de8dbaf6d9e41481c460ba31ca61e163d7348f8e
-F test/where.test 66d4c107e82dfe86c01a96277b77e7a8809aff0b
+F test/where.test 9902a3d84e9bc80357a2c54ed0e76c0d6d04a867
 F test/where2.test af78c55589cbc82d793449493adba0dc3d659f23
 F test/where3.test 1ad55ba900bd7747f98b6082e65bd3e442c5004e
-F test/where4.test 44f506bf1737cf0fa4fc795e340208250f1fcd89
+F test/where4.test 4a371bfcc607f41d233701bdec33ac2972908ba8
 F test/where5.test fdf66f96d29a064b63eb543e28da4dfdccd81ad2
 F test/where6.test 5da5a98cec820d488e82708301b96cb8c18a258b
 F test/where7.test 5a4b0abc207d71da4deecd734ad8579e8dd40aa8
@@ -1398,10 +1398,7 @@ F tool/vdbe_profile.tcl 246d0da094856d72d2c12efec03250d71639d19f
 F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh 48bd54594752d5be3337f12c72f28d2080cb630b
 F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
-P 445480095e6877cce8220b1c095f334bbb04c1c3
-R 05aade661a6de043d2b7f27fd40fb41a
-T *branch * seekeq-experiment
-T *sym-seekeq-experiment *
-T -sym-trunk *
+P 32e31b9bc8664afcd326a1ff3892d86dc5202474
+R 39eaab676629cc3889ae2b19a383806f
 U drh
-Z 34383bd81ccfcce5590ebe9ba011f808
+Z 569a968eaa17fd575e8f13c4e6f1f518

manifest.uuid

@@ -1 +1 @@
-32e31b9bc8664afcd326a1ff3892d86dc5202474
+997ce6c90b454c03cc2ef6934752ee8dd2e520e3

src/btree.c

@@ -5041,6 +5041,8 @@ int sqlite3BtreeLast(BtCursor *pCur, int *pRes){
 **     *pRes>0      The cursor is left pointing at an entry that
 **                  is larger than intKey/pIdxKey.
 **
+** For index tables, the pIdxKey->eqSeen field is set to 1 if there
+** exists an entry in the table that exactly matches pIdxKey.  
 */
 int sqlite3BtreeMovetoUnpacked(
   BtCursor *pCur,          /* The cursor to be moved */
@@ -9644,7 +9646,6 @@ int sqlite3BtreeSetVersion(Btree *pBtree, int iVersion){
   return rc;
 }
 
-#ifdef SQLITE_DEBUG
 /*
 ** Return true if the cursor has a hint specified.  This routine is
 ** only used from within assert() statements
@@ -9652,7 +9653,6 @@ int sqlite3BtreeSetVersion(Btree *pBtree, int iVersion){
 int sqlite3BtreeCursorHasHint(BtCursor *pCsr, unsigned int mask){
   return (pCsr->hints & mask)!=0;
 }
-#endif
 
 /*
 ** Return true if the given Btree is read-only.

src/btree.h

@@ -257,9 +257,7 @@ int sqlite3BtreePutData(BtCursor*, u32 offset, u32 amt, void*);
 void sqlite3BtreeIncrblobCursor(BtCursor *);
 void sqlite3BtreeClearCursor(BtCursor *);
 int sqlite3BtreeSetVersion(Btree *pBt, int iVersion);
-#ifdef SQLITE_DEBUG
 int sqlite3BtreeCursorHasHint(BtCursor*, unsigned int mask);
-#endif
 int sqlite3BtreeIsReadonly(Btree *pBt);
 int sqlite3HeaderSizeBtree(void);
 

src/sqliteInt.h

@@ -1812,9 +1812,8 @@ struct KeyInfo {
 };
 
 /*
-** An instance of the following structure holds information about a
-** single index record that has already been parsed out into individual
-** values.
+** This object holds a record which has been parsed out into individual
+** fields, for the purposes of doing a comparison.
 **
 ** A record is an object that contains one or more fields of data.
 ** Records are used to store the content of a table row and to store
@@ -1822,11 +1821,30 @@ struct KeyInfo {
 ** the OP_MakeRecord opcode of the VDBE and is disassembled by the
 ** OP_Column opcode.
 **
-** This structure holds a record that has already been disassembled
-** into its constituent fields.
+** An instance of this object serves as a "key" for doing a search on
+** an index b+tree. The goal of the search is to find the entry that
+** is closed to the key described by this object.  This object might hold
+** just a prefix of the key.  The number of fields is given by
+** pKeyInfo->nField.
 **
-** The r1 and r2 member variables are only used by the optimized comparison
-** functions vdbeRecordCompareInt() and vdbeRecordCompareString().
+** The r1 and r2 fields are the values to return if this key is less than
+** or greater than a key in the btree, respectively.  These are normally
+** -1 and +1 respectively, but might be inverted to +1 and -1 if the b-tree
+** is in DESC order.
+**
+** The key comparison functions actually return default_rc when they find
+** an equals comparison.  default_rc can be -1, 0, or +1.  If there are
+** multiple entries in the b-tree with the same key (when only looking
+** at the first pKeyInfo->nFields,) then default_rc can be set to -1 to 
+** cause the search to find the last match, or +1 to cause the search to
+** find the first match.
+**
+** The key comparison functions will set eqSeen to true if they ever
+** get and equal results when comparing this structure to a b-tree record.
+** When default_rc!=0, the search might end up on the record immediately
+** before the first match or immediately after the last match.  The
+** eqSeen field will indicate whether or not an exact match exists in the
+** b-tree.
 */
 struct UnpackedRecord {
   KeyInfo *pKeyInfo;  /* Collation and sort-order information */

src/vdbe.c

@@ -3597,6 +3597,13 @@ case OP_ColumnsUsed: {
 ** is greater than or equal to the key value. If there are no records 
 ** greater than or equal to the key and P2 is not zero, then jump to P2.
 **
+** If the cursor P1 was opened using the OPFLAG_SEEKEQ flag, then this
+** opcode will always land on a record that equally equals the key, or
+** else jump immediately to P2.  When the cursor is OPFLAG_SEEKEQ, this
+** opcode must be followed by an IdxLE opcode with the same arguments.
+** The IdxLE opcode will be skipped if this opcode succeeds, but the
+** IdxLE opcode will be used on subsequent loop iterations.
+**
 ** This opcode leaves the cursor configured to move in forward order,
 ** from the beginning toward the end.  In other words, the cursor is
 ** configured to use Next, not Prev.
@@ -3655,18 +3662,26 @@ case OP_ColumnsUsed: {
 ** from the end toward the beginning.  In other words, the cursor is
 ** configured to use Prev, not Next.
 **
+** If the cursor P1 was opened using the OPFLAG_SEEKEQ flag, then this
+** opcode will always land on a record that equally equals the key, or
+** else jump immediately to P2.  When the cursor is OPFLAG_SEEKEQ, this
+** opcode must be followed by an IdxGE opcode with the same arguments.
+** The IdxGE opcode will be skipped if this opcode succeeds, but the
+** IdxGE opcode will be used on subsequent loop iterations.
+**
 ** See also: Found, NotFound, SeekGt, SeekGe, SeekLt
 */
 case OP_SeekLT:         /* jump, in3 */
 case OP_SeekLE:         /* jump, in3 */
 case OP_SeekGE:         /* jump, in3 */
 case OP_SeekGT: {       /* jump, in3 */
-  int res;
-  int oc;
-  VdbeCursor *pC;
-  UnpackedRecord r;
-  int nField;
+  int res;           /* Comparison result */
+  int oc;            /* Opcode */
+  VdbeCursor *pC;    /* The cursor to seek */
+  UnpackedRecord r;  /* The key to seek for */
+  int nField;        /* Number of columns or fields in the key */
   i64 iKey;          /* The rowid we are to seek to */
+  int eqOnly = 0;    /* Only interested in == results */
 
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
   assert( pOp->p2!=0 );
@@ -3688,18 +3703,15 @@ case OP_SeekGT: {       /* jump, in3 */
   ** OP_SeekLE opcodes are allowed, and these must be immediately followed
   ** by an OP_IdxGT or OP_IdxLT opcode, respectively, with the same key.
   */
-#ifdef SQLITE_DEBUG
   if( sqlite3BtreeCursorHasHint(pC->pCursor, BTREE_SEEK_EQ) ){
+    eqOnly = 1;
     assert( pOp->opcode==OP_SeekGE || pOp->opcode==OP_SeekLE );
-#if 0
     assert( pOp[1].opcode==OP_IdxLT || pOp[1].opcode==OP_IdxGT );
     assert( pOp[1].p1==pOp[0].p1 );
     assert( pOp[1].p2==pOp[0].p2 );
     assert( pOp[1].p3==pOp[0].p3 );
     assert( pOp[1].p4.i==pOp[0].p4.i );
-#endif
   }
-#endif
  
   if( pC->isTable ){
     /* The input value in P3 might be of any type: integer, real, string,
@@ -3749,6 +3761,7 @@ case OP_SeekGT: {       /* jump, in3 */
     if( rc!=SQLITE_OK ){
       goto abort_due_to_error;
     }
+    if( eqOnly && res ) goto seek_not_found;
   }else{
     nField = pOp->p4.i;
     assert( pOp->p4type==P4_INT32 );
@@ -3779,8 +3792,9 @@ case OP_SeekGT: {       /* jump, in3 */
     if( rc!=SQLITE_OK ){
       goto abort_due_to_error;
     }
-    if( (pOp->p5 & OPFLAG_SEEKEQ)!=0 && r.eqSeen==0 ){
-      goto take_the_jump;
+    if( eqOnly && r.eqSeen==0 ){
+      assert( res!=0 );
+      goto seek_not_found;
     }
   }
   pC->deferredMoveto = 0;
@@ -3809,11 +3823,14 @@ case OP_SeekGT: {       /* jump, in3 */
       res = sqlite3BtreeEof(pC->pCursor);
     }
   }
-take_the_jump:
+seek_not_found:
   assert( pOp->p2>0 );
   VdbeBranchTaken(res!=0,2);
   if( res ){
     goto jump_to_p2;
+  }else if( eqOnly ){
+    assert( pOp[1].opcode==OP_IdxLT || pOp[1].opcode==OP_IdxGT );
+    pOp++; /* Skip the OP_IdxLt or OP_IdxGT that follows */
   }
   break;
 }

src/wherecode.c

@@ -1026,7 +1026,6 @@ Bitmask sqlite3WhereCodeOneLoopStart(
     WhereTerm *pRangeEnd = 0;    /* Inequality constraint at range end */
     int startEq;                 /* True if range start uses ==, >= or <= */
     int endEq;                   /* True if range end uses ==, >= or <= */
-    int eqOnly;                  /* True if uses only == */
     int start_constraints;       /* Start of range is constrained */
     int nConstraint;             /* Number of constraint terms */
     Index *pIdx;                 /* The index we will be using */
@@ -1096,8 +1095,6 @@ Bitmask sqlite3WhereCodeOneLoopStart(
       }
     }
     assert( pRangeEnd==0 || (pRangeEnd->wtFlags & TERM_VNULL)==0 );
-    eqOnly = nEq>0 && (pLoop->wsFlags & WHERE_COLUMN_RANGE)==0
-                   && (pWInfo->wctrlFlags&WHERE_ORDERBY_MIN)==0;
 
     /* If we are doing a reverse order scan on an ascending index, or
     ** a forward order scan on a descending index, interchange the 
@@ -1170,7 +1167,6 @@ Bitmask sqlite3WhereCodeOneLoopStart(
     VdbeCoverageIf(v, op==OP_SeekGE);  testcase( op==OP_SeekGE );
     VdbeCoverageIf(v, op==OP_SeekLE);  testcase( op==OP_SeekLE );
     VdbeCoverageIf(v, op==OP_SeekLT);  testcase( op==OP_SeekLT );
-    if( eqOnly ) sqlite3VdbeChangeP5(v, OPFLAG_SEEKEQ);
 
     /* Load the value for the inequality constraint at the end of the
     ** range (if any).
@@ -1206,11 +1202,6 @@ Bitmask sqlite3WhereCodeOneLoopStart(
 
     /* Check if the index cursor is past the end of the range. */
     if( nConstraint ){
-      if( eqOnly ){
-        int bx = sqlite3VdbeCurrentAddr(v);
-        sqlite3VdbeAddOp2(v, OP_Goto, 0, bx+2);
-        pLevel->p2 = bx+1;
-      }
       op = aEndOp[bRev*2 + endEq];
       sqlite3VdbeAddOp4Int(v, op, iIdxCur, addrNxt, regBase, nConstraint);
       testcase( op==OP_IdxGT );  VdbeCoverageIf(v, op==OP_IdxGT );

test/collate4.test

@@ -352,7 +352,7 @@ do_test collate4-2.1.2 {
   count {
     SELECT * FROM collate4t2, collate4t1 WHERE a = b;
   }
-} {A a A A 5}
+} {A a A A 4}
 do_test collate4-2.1.3 {
   count {
     SELECT * FROM collate4t2, collate4t1 WHERE b = a;
@@ -372,7 +372,7 @@ do_test collate4-2.1.5 {
   count {
     SELECT * FROM collate4t2, collate4t1 WHERE b = a;
   }
-} {A A 4}
+} {A A 3}
 ifcapable subquery {
   do_test collate4-2.1.6 {
     count {
@@ -389,12 +389,12 @@ ifcapable subquery {
       SELECT a FROM collate4t1 WHERE a IN (SELECT * FROM collate4t2)
        ORDER BY rowid
     }
-  } {a A 6}
+  } {a A 5}
   do_test collate4-2.1.8 {
     count {
       SELECT a FROM collate4t1 WHERE a IN ('z', 'a');
     }
-  } {a A 5}
+  } {a A 4}
   do_test collate4-2.1.9 {
     execsql {
       DROP INDEX collate4i1;

test/where.test

@@ -412,22 +412,22 @@ ifcapable subquery {
     count {
       SELECT * FROM t1 WHERE w IN (-1,1,2,3) order by 1;
     }
-  } {1 0 4 2 1 9 3 1 16 13}
+  } {1 0 4 2 1 9 3 1 16 12}
   do_test where-5.3b {
     count {
       SELECT * FROM t1 WHERE w IN (3,-1,1,2) order by 1;
     }
-  } {1 0 4 2 1 9 3 1 16 13}
+  } {1 0 4 2 1 9 3 1 16 12}
   do_test where-5.3c {
     count {
       SELECT * FROM t1 WHERE w IN (3,2,-1,1,2) order by 1;
     }
-  } {1 0 4 2 1 9 3 1 16 13}
+  } {1 0 4 2 1 9 3 1 16 12}
   do_test where-5.3d {
     count {
       SELECT * FROM t1 WHERE w IN (-1,1,2,3) order by 1 DESC;
     }
-  } {3 1 16 2 1 9 1 0 4 12}
+  } {3 1 16 2 1 9 1 0 4 11}
   do_test where-5.4 {
     count {
       SELECT * FROM t1 WHERE w+0 IN (-1,1,2,3) order by 1;
@@ -465,7 +465,7 @@ ifcapable subquery {
     count {
       SELECT * FROM t1 WHERE x IN (1,7) ORDER BY 1;
     }
-  } {2 1 9 3 1 16 7}
+  } {2 1 9 3 1 16 6}
   do_test where-5.10 {
     count {
       SELECT * FROM t1 WHERE x+0 IN (1,7) ORDER BY 1;
@@ -485,17 +485,17 @@ ifcapable subquery {
     count {
       SELECT * FROM t1 WHERE x IN (1,7) AND y NOT IN (6400,8100) ORDER BY 1;
     }
-  } {2 1 9 3 1 16 7}
+  } {2 1 9 3 1 16 6}
   do_test where-5.14 {
     count {
       SELECT * FROM t1 WHERE x IN (1,7) AND y IN (9,10) ORDER BY 1;
     }
-  } {2 1 9 8}
+  } {2 1 9 5}
   do_test where-5.15 {
     count {
       SELECT * FROM t1 WHERE x IN (1,7) AND y IN (9,16) ORDER BY 1;
     }
-  } {2 1 9 3 1 16 11}
+  } {2 1 9 3 1 16 9}
   do_test where-5.100 {
     db eval {
       SELECT w, x, y FROM t1 WHERE x IN (1,5) AND y IN (9,8,3025,1000,3969)

test/where4.test

@@ -91,7 +91,7 @@ do_test where4-1.10 {
 } {6 2}
 do_test where4-1.11 {
   count {SELECT rowid FROM t1 WHERE w=x'78' AND x IS NULL AND y=123}
-} {1}
+} {0}
 do_test where4-1.12 {
   count {SELECT rowid FROM t1 WHERE w=x'78' AND x IS NULL AND y=x'7A'}
 } {6 2}