-C Fix\sexprAnalyze()\safter\srecent\sperformance\senhancements\sso\sthat\sit\sis\sable\nto\shandle\sIF_NULL_ROW\sopcode\scorrectly,\sagain.
-D 2021-12-03T15:48:42.503
+C Factor\sthe\snoop-join-elimination\soptimization\sout\sof\sthe\ssqlite3WhereBegin()\nroutine\sand\sinto\sa\sseparate\s"no-inline"\ssubroutine,\sin\sorder\sto\sreduce\sthe\ncomplexity\sof\ssqlite3WhereBegin()\sand\sthereby\sencourage\sC\scompilers\sto\ninline\ssqlite3WhereCodeOneLoopStart().
+D 2021-12-03T18:53:53.434
F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
F src/wal.c ed0398a7adf02c31e34aada42cc86c58f413a7afe5f741a5d373ad087abde028
F src/wal.h c3aa7825bfa2fe0d85bef2db94655f99870a285778baa36307c0a16da32b226a
F src/walker.c f890a3298418d7cba3b69b8803594fdc484ea241206a8dfa99db6dd36f8cbb3b
-F src/where.c b50391df607937593596fbb8ea39f673d9a3715a65750567b442d22dd20720ca
+F src/where.c 5bd26902ddf3e385c0df9429b10e7358bbd0430c470ec1d2a53065723c4a55d2
F src/whereInt.h 1630d9418512b080598e9a72b8af6b8bd1b9ab13fee1458f151762b6df206791
F src/wherecode.c 1f5b62f46d284c8886945eb7438415bc27e23e87bb60b9ee468fa6bd31268f33
F src/whereexpr.c 19394cb463003e9cc9305730b1508b8817a22bb7247170d81234b691a7f05b89
F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P f3d6853ee80be2dc6d7236d98b850beb0e1931a624d4f5b194c8db742cde7ec5
-R f7c21b32b86d486ed00c79fd5643ce8f
+P 8029e6bab508bf0b8ec1df00a829c5d4de2a84d66dc56b9ff03da879ceef7788
+R 963c220f26757d3ffbc2edfb4f7e86f0
U drh
-Z 7b145c2e945c01598a45c251b2a2a878
+Z 180dbfc838231c2ae95c395bdf32b1d2
# define WHERETRACE_ALL_LOOPS(W,C)
#endif
+/* Attempt to omit tables from a join that do not affect the result.
+** For a table to not affect the result, the following must be true:
+**
+** 1) The query must not be an aggregate.
+** 2) The table must be the RHS of a LEFT JOIN.
+** 3) Either the query must be DISTINCT, or else the ON or USING clause
+** must contain a constraint that limits the scan of the table to
+** at most a single row.
+** 4) The table must not be referenced by any part of the query apart
+** from its own USING or ON clause.
+**
+** For example, given:
+**
+** CREATE TABLE t1(ipk INTEGER PRIMARY KEY, v1);
+** CREATE TABLE t2(ipk INTEGER PRIMARY KEY, v2);
+** CREATE TABLE t3(ipk INTEGER PRIMARY KEY, v3);
+**
+** then table t2 can be omitted from the following:
+**
+** SELECT v1, v3 FROM t1
+** LEFT JOIN t2 ON (t1.ipk=t2.ipk)
+** LEFT JOIN t3 ON (t1.ipk=t3.ipk)
+**
+** or from:
+**
+** SELECT DISTINCT v1, v3 FROM t1
+** LEFT JOIN t2
+** LEFT JOIN t3 ON (t1.ipk=t3.ipk)
+*/
+static SQLITE_NOINLINE Bitmask whereOmitNoopJoin(
+ WhereInfo *pWInfo,
+ Bitmask notReady
+){
+ int i;
+ Bitmask tabUsed;
+
+ /* Preconditions checked by the caller */
+ assert( pWInfo->nLevel>=2 );
+ assert( OptimizationEnabled(pWInfo->pParse->db, SQLITE_OmitNoopJoin) );
+
+ /* These two preconditions checked by the caller combine to guarantee
+ ** condition (1) of the header comment */
+ assert( pWInfo->pResultSet!=0 );
+ assert( 0==(pWInfo->wctrlFlags & WHERE_AGG_DISTINCT) );
+
+ tabUsed = sqlite3WhereExprListUsage(&pWInfo->sMaskSet, pWInfo->pResultSet);
+ if( pWInfo->pOrderBy ){
+ tabUsed |= sqlite3WhereExprListUsage(&pWInfo->sMaskSet, pWInfo->pOrderBy);
+ }
+ for(i=pWInfo->nLevel-1; i>=1; i--){
+ WhereTerm *pTerm, *pEnd;
+ SrcItem *pItem;
+ WhereLoop *pLoop;
+ pLoop = pWInfo->a[i].pWLoop;
+ pItem = &pWInfo->pTabList->a[pLoop->iTab];
+ if( (pItem->fg.jointype & JT_LEFT)==0 ) continue;
+ if( (pWInfo->wctrlFlags & WHERE_WANT_DISTINCT)==0
+ && (pLoop->wsFlags & WHERE_ONEROW)==0
+ ){
+ continue;
+ }
+ if( (tabUsed & pLoop->maskSelf)!=0 ) continue;
+ pEnd = pWInfo->sWC.a + pWInfo->sWC.nTerm;
+ for(pTerm=pWInfo->sWC.a; pTerm<pEnd; pTerm++){
+ if( (pTerm->prereqAll & pLoop->maskSelf)!=0 ){
+ if( !ExprHasProperty(pTerm->pExpr, EP_FromJoin)
+ || pTerm->pExpr->iRightJoinTable!=pItem->iCursor
+ ){
+ break;
+ }
+ }
+ }
+ if( pTerm<pEnd ) continue;
+ WHERETRACE(0xffff, ("-> drop loop %c not used\n", pLoop->cId));
+ notReady &= ~pLoop->maskSelf;
+ for(pTerm=pWInfo->sWC.a; pTerm<pEnd; pTerm++){
+ if( (pTerm->prereqAll & pLoop->maskSelf)!=0 ){
+ pTerm->wtFlags |= TERM_CODED;
+ }
+ }
+ if( i!=pWInfo->nLevel-1 ){
+ int nByte = (pWInfo->nLevel-1-i) * sizeof(WhereLevel);
+ memmove(&pWInfo->a[i], &pWInfo->a[i+1], nByte);
+ }
+ pWInfo->nLevel--;
+ assert( pWInfo->nLevel>0 );
+ }
+ return notReady;
+}
+
/*
** Generate the beginning of the loop used for WHERE clause processing.
** The return value is a pointer to an opaque structure that contains
}
#endif
- /* Attempt to omit tables from the join that do not affect the result.
- ** For a table to not affect the result, the following must be true:
- **
- ** 1) The query must not be an aggregate.
- ** 2) The table must be the RHS of a LEFT JOIN.
- ** 3) Either the query must be DISTINCT, or else the ON or USING clause
- ** must contain a constraint that limits the scan of the table to
- ** at most a single row.
- ** 4) The table must not be referenced by any part of the query apart
- ** from its own USING or ON clause.
- **
- ** For example, given:
+ /* Attempt to omit tables from a join that do not affect the result.
+ ** See the comment on whereOmitNoopJoin() for further information.
**
- ** CREATE TABLE t1(ipk INTEGER PRIMARY KEY, v1);
- ** CREATE TABLE t2(ipk INTEGER PRIMARY KEY, v2);
- ** CREATE TABLE t3(ipk INTEGER PRIMARY KEY, v3);
- **
- ** then table t2 can be omitted from the following:
- **
- ** SELECT v1, v3 FROM t1
- ** LEFT JOIN t2 ON (t1.ipk=t2.ipk)
- ** LEFT JOIN t3 ON (t1.ipk=t3.ipk)
- **
- ** or from:
- **
- ** SELECT DISTINCT v1, v3 FROM t1
- ** LEFT JOIN t2
- ** LEFT JOIN t3 ON (t1.ipk=t3.ipk)
+ ** This query optimization is factored out into a separate "no-inline"
+ ** procedure to keep the sqlite3WhereBegin() procedure from becoming
+ ** too large. If sqlite3WhereBegin() becomes too large, that prevents
+ ** some C-compiler optimizers from in-lining the
+ ** sqlite3WhereCodeOneLoopStart() procedure, and it is important to
+ ** in-line sqlite3WhereCodeOneLoopStart() for performance reasons.
*/
notReady = ~(Bitmask)0;
if( pWInfo->nLevel>=2
&& 0==(wctrlFlags & WHERE_AGG_DISTINCT) /* condition (1) above */
&& OptimizationEnabled(db, SQLITE_OmitNoopJoin)
){
- int i;
- Bitmask tabUsed = sqlite3WhereExprListUsage(pMaskSet, pResultSet);
- if( sWLB.pOrderBy ){
- tabUsed |= sqlite3WhereExprListUsage(pMaskSet, sWLB.pOrderBy);
- }
- for(i=pWInfo->nLevel-1; i>=1; i--){
- WhereTerm *pTerm, *pEnd;
- SrcItem *pItem;
- pLoop = pWInfo->a[i].pWLoop;
- pItem = &pWInfo->pTabList->a[pLoop->iTab];
- if( (pItem->fg.jointype & JT_LEFT)==0 ) continue;
- if( (wctrlFlags & WHERE_WANT_DISTINCT)==0
- && (pLoop->wsFlags & WHERE_ONEROW)==0
- ){
- continue;
- }
- if( (tabUsed & pLoop->maskSelf)!=0 ) continue;
- pEnd = sWLB.pWC->a + sWLB.pWC->nTerm;
- for(pTerm=sWLB.pWC->a; pTerm<pEnd; pTerm++){
- if( (pTerm->prereqAll & pLoop->maskSelf)!=0 ){
- if( !ExprHasProperty(pTerm->pExpr, EP_FromJoin)
- || pTerm->pExpr->iRightJoinTable!=pItem->iCursor
- ){
- break;
- }
- }
- }
- if( pTerm<pEnd ) continue;
- WHERETRACE(0xffff, ("-> drop loop %c not used\n", pLoop->cId));
- notReady &= ~pLoop->maskSelf;
- for(pTerm=sWLB.pWC->a; pTerm<pEnd; pTerm++){
- if( (pTerm->prereqAll & pLoop->maskSelf)!=0 ){
- pTerm->wtFlags |= TERM_CODED;
- }
- }
- if( i!=pWInfo->nLevel-1 ){
- int nByte = (pWInfo->nLevel-1-i) * sizeof(WhereLevel);
- memmove(&pWInfo->a[i], &pWInfo->a[i+1], nByte);
- }
- pWInfo->nLevel--;
- nTabList--;
- }
+ notReady = whereOmitNoopJoin(pWInfo, notReady);
+ nTabList = pWInfo->nLevel;
+ assert( nTabList>0 );
}
+
#if defined(WHERETRACE_ENABLED)
if( sqlite3WhereTrace & 0x100 ){ /* Display all terms of the WHERE clause */
sqlite3DebugPrintf("---- WHERE clause at end of analysis:\n");
projects / thirdparty / sqlite.git / commitdiff
