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Overview
Comment: | Remove an unused subfunction parameter and an obsolete comment from the query planner logic in where.c. |
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Timelines: | family | ancestors | descendants | both | trunk |
Files: | files | file ages | folders |
SHA1: |
349a55cd8ba9ce65ebfd987ecfebd120 |
User & Date: | drh 2012-09-24 19:50:00.842 |
Context
2012-09-27
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12:11 | Merge the "PRAGMA busy_timeout" change into trunk. (check-in: 1a679a1ef3 user: drh tags: trunk) | |
2012-09-25
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14:29 | Pass information around between the major routines of the query planner using a single pointer to a structure rather than a long list of parameters. (check-in: 1104d42e10 user: drh tags: qp-enhancements) | |
12:45 | Merge updates from trunk. (check-in: 4a470741b6 user: mistachkin tags: configReadOnly) | |
2012-09-24
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19:50 | Remove an unused subfunction parameter and an obsolete comment from the query planner logic in where.c. (check-in: 349a55cd8b user: drh tags: trunk) | |
15:30 | Change the internal sqlite3WhereBegin() to report that the ORDER BY clause is satisfied by indices using the WhereInfo.nOBSat field of the returned structure. (check-in: 22989f3588 user: drh tags: trunk) | |
Changes
Changes to src/where.c.
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1809 1810 1811 1812 1813 1814 1815 | #endif /* ** Required because bestIndex() is called by bestOrClauseIndex() */ static void bestIndex( Parse*, WhereClause*, struct SrcList_item*, | | | 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 | #endif /* ** Required because bestIndex() is called by bestOrClauseIndex() */ static void bestIndex( Parse*, WhereClause*, struct SrcList_item*, Bitmask, Bitmask, WhereCost*); /* ** This routine attempts to find an scanning strategy that can be used ** to optimize an 'OR' expression that is part of a WHERE clause. ** ** The table associated with FROM clause term pSrc may be either a ** regular B-Tree table or a virtual table. |
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1863 1864 1865 1866 1867 1868 1869 | for(pOrTerm=pOrWC->a; pOrTerm<pOrWCEnd; pOrTerm++){ WhereCost sTermCost; WHERETRACE(("... Multi-index OR testing for term %d of %d....\n", (pOrTerm - pOrWC->a), (pTerm - pWC->a) )); if( pOrTerm->eOperator==WO_AND ){ WhereClause *pAndWC = &pOrTerm->u.pAndInfo->wc; | | | | 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 | for(pOrTerm=pOrWC->a; pOrTerm<pOrWCEnd; pOrTerm++){ WhereCost sTermCost; WHERETRACE(("... Multi-index OR testing for term %d of %d....\n", (pOrTerm - pOrWC->a), (pTerm - pWC->a) )); if( pOrTerm->eOperator==WO_AND ){ WhereClause *pAndWC = &pOrTerm->u.pAndInfo->wc; bestIndex(pParse, pAndWC, pSrc, notReady, notValid, &sTermCost); }else if( pOrTerm->leftCursor==iCur ){ WhereClause tempWC; tempWC.pParse = pWC->pParse; tempWC.pMaskSet = pWC->pMaskSet; tempWC.pOuter = pWC; tempWC.op = TK_AND; tempWC.a = pOrTerm; tempWC.wctrlFlags = 0; tempWC.nTerm = 1; bestIndex(pParse, &tempWC, pSrc, notReady, notValid, &sTermCost); }else{ continue; } rTotal += sTermCost.rCost; nRow += sTermCost.plan.nRow; used |= sTermCost.used; if( rTotal>=pCost->rCost ) break; |
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3384 3385 3386 3387 3388 3389 3390 3391 3392 3393 3394 3395 3396 3397 | } /* ** Find the query plan for accessing table pSrc->pTab. Write the ** best query plan and its cost into the WhereCost object supplied ** as the last parameter. This function may calculate the cost of ** both real and virtual table scans. */ static void bestIndex( Parse *pParse, /* The parsing context */ WhereClause *pWC, /* The WHERE clause */ struct SrcList_item *pSrc, /* The FROM clause term to search */ Bitmask notReady, /* Mask of cursors not available for indexing */ Bitmask notValid, /* Cursors not available for any purpose */ | > > > > > > < | | | 3384 3385 3386 3387 3388 3389 3390 3391 3392 3393 3394 3395 3396 3397 3398 3399 3400 3401 3402 3403 3404 3405 3406 3407 3408 3409 3410 3411 3412 3413 3414 3415 3416 3417 3418 3419 3420 3421 3422 3423 3424 | } /* ** Find the query plan for accessing table pSrc->pTab. Write the ** best query plan and its cost into the WhereCost object supplied ** as the last parameter. This function may calculate the cost of ** both real and virtual table scans. ** ** This function does not take ORDER BY or DISTINCT into account. Nor ** does it remember the virtual table query plan. All it does is compute ** the cost while determining if an OR optimization is applicable. The ** details will be reconsidered later if the optimization is found to be ** applicable. */ static void bestIndex( Parse *pParse, /* The parsing context */ WhereClause *pWC, /* The WHERE clause */ struct SrcList_item *pSrc, /* The FROM clause term to search */ Bitmask notReady, /* Mask of cursors not available for indexing */ Bitmask notValid, /* Cursors not available for any purpose */ WhereCost *pCost /* Lowest cost query plan */ ){ #ifndef SQLITE_OMIT_VIRTUALTABLE if( IsVirtual(pSrc->pTab) ){ sqlite3_index_info *p = 0; bestVirtualIndex(pParse, pWC, pSrc, notReady, notValid, 0, pCost, &p); if( p->needToFreeIdxStr ){ sqlite3_free(p->idxStr); } sqlite3DbFree(pParse->db, p); }else #endif { bestBtreeIndex(pParse, pWC, pSrc, notReady, notValid, 0, 0, pCost); } } /* ** Disable a term in the WHERE clause. Except, do not disable the term ** if it controls a LEFT OUTER JOIN and it did not originate in the ON ** or USING clause of that join. |
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4694 4695 4696 4697 4698 4699 4700 | int nTabList; /* Number of elements in pTabList */ WhereInfo *pWInfo; /* Will become the return value of this function */ Vdbe *v = pParse->pVdbe; /* The virtual database engine */ Bitmask notReady; /* Cursors that are not yet positioned */ WhereMaskSet *pMaskSet; /* The expression mask set */ WhereClause *pWC; /* Decomposition of the WHERE clause */ struct SrcList_item *pTabItem; /* A single entry from pTabList */ | | | 4699 4700 4701 4702 4703 4704 4705 4706 4707 4708 4709 4710 4711 4712 4713 | int nTabList; /* Number of elements in pTabList */ WhereInfo *pWInfo; /* Will become the return value of this function */ Vdbe *v = pParse->pVdbe; /* The virtual database engine */ Bitmask notReady; /* Cursors that are not yet positioned */ WhereMaskSet *pMaskSet; /* The expression mask set */ WhereClause *pWC; /* Decomposition of the WHERE clause */ struct SrcList_item *pTabItem; /* A single entry from pTabList */ WhereLevel *pLevel; /* A single level in pWInfo->a[] */ int iFrom; /* First unused FROM clause element */ int andFlags; /* AND-ed combination of all pWC->a[].wtFlags */ sqlite3 *db; /* Database connection */ /* The number of tables in the FROM clause is limited by the number of ** bits in a Bitmask */ |
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4990 4991 4992 4993 4994 4995 4996 | } } assert( bestJ>=0 ); assert( notReady & getMask(pMaskSet, pTabList->a[bestJ].iCursor) ); WHERETRACE(("*** Optimizer selects table %d for loop %d" " with cost=%g and nRow=%g\n", bestJ, pLevel-pWInfo->a, bestPlan.rCost, bestPlan.plan.nRow)); | < | 4995 4996 4997 4998 4999 5000 5001 5002 5003 5004 5005 5006 5007 5008 | } } assert( bestJ>=0 ); assert( notReady & getMask(pMaskSet, pTabList->a[bestJ].iCursor) ); WHERETRACE(("*** Optimizer selects table %d for loop %d" " with cost=%g and nRow=%g\n", bestJ, pLevel-pWInfo->a, bestPlan.rCost, bestPlan.plan.nRow)); if( (bestPlan.plan.wsFlags & WHERE_ORDERBY)!=0 ){ pWInfo->nOBSat = pOrderBy->nExpr; } if( (bestPlan.plan.wsFlags & WHERE_DISTINCT)!=0 ){ assert( pWInfo->eDistinct==0 ); pWInfo->eDistinct = WHERE_DISTINCT_ORDERED; } |
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