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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-06-03 05:16:44 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-06-03 05:16:44 +0000 |
commit | 62a67b10ff9f9eea6a4695649fb8252d2a4bc74d (patch) | |
tree | 7b54cadc082d323cda5fd24248e85b7d2ea664a3 /src/wherecode.c | |
parent | Adding debian version 3.45.3-1. (diff) | |
download | sqlite3-62a67b10ff9f9eea6a4695649fb8252d2a4bc74d.tar.xz sqlite3-62a67b10ff9f9eea6a4695649fb8252d2a4bc74d.zip |
Merging upstream version 3.46.0.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/wherecode.c')
-rw-r--r-- | src/wherecode.c | 42 |
1 files changed, 40 insertions, 2 deletions
diff --git a/src/wherecode.c b/src/wherecode.c index 47ce36c..a620a5a 100644 --- a/src/wherecode.c +++ b/src/wherecode.c @@ -1338,6 +1338,27 @@ static SQLITE_NOINLINE void filterPullDown( } /* +** Loop pLoop is a WHERE_INDEXED level that uses at least one IN(...) +** operator. Return true if level pLoop is guaranteed to visit only one +** row for each key generated for the index. +*/ +static int whereLoopIsOneRow(WhereLoop *pLoop){ + if( pLoop->u.btree.pIndex->onError + && pLoop->nSkip==0 + && pLoop->u.btree.nEq==pLoop->u.btree.pIndex->nKeyCol + ){ + int ii; + for(ii=0; ii<pLoop->u.btree.nEq; ii++){ + if( pLoop->aLTerm[ii]->eOperator & (WO_IS|WO_ISNULL) ){ + return 0; + } + } + return 1; + } + return 0; +} + +/* ** Generate code for the start of the iLevel-th loop in the WHERE clause ** implementation described by pWInfo. */ @@ -1415,7 +1436,7 @@ Bitmask sqlite3WhereCodeOneLoopStart( if( pLevel->iFrom>0 && (pTabItem[0].fg.jointype & JT_LEFT)!=0 ){ pLevel->iLeftJoin = ++pParse->nMem; sqlite3VdbeAddOp2(v, OP_Integer, 0, pLevel->iLeftJoin); - VdbeComment((v, "init LEFT JOIN no-match flag")); + VdbeComment((v, "init LEFT JOIN match flag")); } /* Compute a safe address to jump to if we discover that the table for @@ -2084,7 +2105,9 @@ Bitmask sqlite3WhereCodeOneLoopStart( } /* Record the instruction used to terminate the loop. */ - if( pLoop->wsFlags & WHERE_ONEROW ){ + if( (pLoop->wsFlags & WHERE_ONEROW) + || (pLevel->u.in.nIn && regBignull==0 && whereLoopIsOneRow(pLoop)) + ){ pLevel->op = OP_Noop; }else if( bRev ){ pLevel->op = OP_Prev; @@ -2474,6 +2497,12 @@ Bitmask sqlite3WhereCodeOneLoopStart( ** iLoop==3: Code all remaining expressions. ** ** An effort is made to skip unnecessary iterations of the loop. + ** + ** This optimization of causing simple query restrictions to occur before + ** more complex one is call the "push-down" optimization in MySQL. Here + ** in SQLite, the name is "MySQL push-down", since there is also another + ** totally unrelated optimization called "WHERE-clause push-down". + ** Sometimes the qualifier is omitted, resulting in an ambiguity, so beware. */ iLoop = (pIdx ? 1 : 2); do{ @@ -2724,7 +2753,16 @@ SQLITE_NOINLINE void sqlite3WhereRightJoinLoop( pRJ->regReturn); for(k=0; k<iLevel; k++){ int iIdxCur; + SrcItem *pRight; + assert( pWInfo->a[k].pWLoop->iTab == pWInfo->a[k].iFrom ); + pRight = &pWInfo->pTabList->a[pWInfo->a[k].iFrom]; mAll |= pWInfo->a[k].pWLoop->maskSelf; + if( pRight->fg.viaCoroutine ){ + sqlite3VdbeAddOp3( + v, OP_Null, 0, pRight->regResult, + pRight->regResult + pRight->pSelect->pEList->nExpr-1 + ); + } sqlite3VdbeAddOp1(v, OP_NullRow, pWInfo->a[k].iTabCur); iIdxCur = pWInfo->a[k].iIdxCur; if( iIdxCur ){ |