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Improvements and simplifications to the equality seek logic. Tests are

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adjusted so that they all pass now.

FossilOrigin-Name: 997ce6c90b454c03cc2ef6934752ee8dd2e520e3
This commit is contained in:
drh
2015-11-05 22:30:54 +00:00
parent 70528d7868
commit b1d607de25
10 changed files with 84 additions and 63 deletions
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43
src/vdbe.c
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@@ -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;
i64 iKey; /* The rowid we are to seek to */
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;
}