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Overview
Comment: | If a skip-scan is a proper subset of some other scan, then adjust the cost of the skip-scan upward so that it is more costly than the other scan. Such a cost imbalance can arise under STAT4 because of difficulties in getting an accurate estimate for skip-scans. |
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Timelines: | family | ancestors | descendants | both | trunk |
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SHA1: |
f4b22a2620a5dc48949048c2ecbd2267 |
User & Date: | drh 2014-10-21 01:05:09.795 |
Context
2014-10-21
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16:01 | Add WHERETRACE debugging output to the whereLoopAdjustCost() routine. (check-in: ec1e942f08 user: drh tags: trunk) | |
01:05 | If a skip-scan is a proper subset of some other scan, then adjust the cost of the skip-scan upward so that it is more costly than the other scan. Such a cost imbalance can arise under STAT4 because of difficulties in getting an accurate estimate for skip-scans. (check-in: f4b22a2620 user: drh tags: trunk) | |
2014-10-17
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21:35 | Fix a (probably harmless) bug in the CSV output mode of the command-line shell. (check-in: 19fe4a0a47 user: drh tags: trunk) | |
Changes
Changes to src/where.c.
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2634 2635 2636 2637 2638 2639 2640 | int nReg; /* Number of registers to allocate */ char *zAff; /* Affinity string to return */ /* This module is only called on query plans that use an index. */ pLoop = pLevel->pWLoop; assert( (pLoop->wsFlags & WHERE_VIRTUALTABLE)==0 ); nEq = pLoop->u.btree.nEq; | | | 2634 2635 2636 2637 2638 2639 2640 2641 2642 2643 2644 2645 2646 2647 2648 | int nReg; /* Number of registers to allocate */ char *zAff; /* Affinity string to return */ /* This module is only called on query plans that use an index. */ pLoop = pLevel->pWLoop; assert( (pLoop->wsFlags & WHERE_VIRTUALTABLE)==0 ); nEq = pLoop->u.btree.nEq; nSkip = pLoop->nSkip; pIdx = pLoop->u.btree.pIndex; assert( pIdx!=0 ); /* Figure out how many memory cells we will need then allocate them. */ regBase = pParse->nMem + 1; nReg = pLoop->u.btree.nEq + nExtraReg; |
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2748 2749 2750 2751 2752 2753 2754 | ** string similar to: ** ** "a=? AND b>?" */ static void explainIndexRange(StrAccum *pStr, WhereLoop *pLoop, Table *pTab){ Index *pIndex = pLoop->u.btree.pIndex; u16 nEq = pLoop->u.btree.nEq; | | | 2748 2749 2750 2751 2752 2753 2754 2755 2756 2757 2758 2759 2760 2761 2762 | ** string similar to: ** ** "a=? AND b>?" */ static void explainIndexRange(StrAccum *pStr, WhereLoop *pLoop, Table *pTab){ Index *pIndex = pLoop->u.btree.pIndex; u16 nEq = pLoop->u.btree.nEq; u16 nSkip = pLoop->nSkip; int i, j; Column *aCol = pTab->aCol; i16 *aiColumn = pIndex->aiColumn; if( nEq==0 && (pLoop->wsFlags&(WHERE_BTM_LIMIT|WHERE_TOP_LIMIT))==0 ) return; sqlite3StrAccumAppend(pStr, " (", 2); for(i=0; i<nEq; i++){ |
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3185 3186 3187 3188 3189 3190 3191 | char *zStartAff; /* Affinity for start of range constraint */ char cEndAff = 0; /* Affinity for end of range constraint */ u8 bSeekPastNull = 0; /* True to seek past initial nulls */ u8 bStopAtNull = 0; /* Add condition to terminate at NULLs */ pIdx = pLoop->u.btree.pIndex; iIdxCur = pLevel->iIdxCur; | | | | 3185 3186 3187 3188 3189 3190 3191 3192 3193 3194 3195 3196 3197 3198 3199 3200 3201 3202 3203 3204 3205 3206 3207 3208 3209 3210 3211 3212 3213 3214 3215 3216 | char *zStartAff; /* Affinity for start of range constraint */ char cEndAff = 0; /* Affinity for end of range constraint */ u8 bSeekPastNull = 0; /* True to seek past initial nulls */ u8 bStopAtNull = 0; /* Add condition to terminate at NULLs */ pIdx = pLoop->u.btree.pIndex; iIdxCur = pLevel->iIdxCur; assert( nEq>=pLoop->nSkip ); /* If this loop satisfies a sort order (pOrderBy) request that ** was passed to this function to implement a "SELECT min(x) ..." ** query, then the caller will only allow the loop to run for ** a single iteration. This means that the first row returned ** should not have a NULL value stored in 'x'. If column 'x' is ** the first one after the nEq equality constraints in the index, ** this requires some special handling. */ assert( pWInfo->pOrderBy==0 || pWInfo->pOrderBy->nExpr==1 || (pWInfo->wctrlFlags&WHERE_ORDERBY_MIN)==0 ); if( (pWInfo->wctrlFlags&WHERE_ORDERBY_MIN)!=0 && pWInfo->nOBSat>0 && (pIdx->nKeyCol>nEq) ){ assert( pLoop->nSkip==0 ); bSeekPastNull = 1; nExtraReg = 1; } /* Find any inequality constraint terms for the start and end ** of the range. */ |
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3823 3824 3825 3826 3827 3828 3829 | }else{ z = sqlite3_mprintf("(%d,%x)", p->u.vtab.idxNum, p->u.vtab.omitMask); } sqlite3DebugPrintf(" %-19s", z); sqlite3_free(z); } if( p->wsFlags & WHERE_SKIPSCAN ){ | | | 3823 3824 3825 3826 3827 3828 3829 3830 3831 3832 3833 3834 3835 3836 3837 | }else{ z = sqlite3_mprintf("(%d,%x)", p->u.vtab.idxNum, p->u.vtab.omitMask); } sqlite3DebugPrintf(" %-19s", z); sqlite3_free(z); } if( p->wsFlags & WHERE_SKIPSCAN ){ sqlite3DebugPrintf(" f %05x %d-%d", p->wsFlags, p->nLTerm,p->nSkip); }else{ sqlite3DebugPrintf(" f %05x N %d", p->wsFlags, p->nLTerm); } sqlite3DebugPrintf(" cost %d,%d,%d\n", p->rSetup, p->rRun, p->nOut); if( p->nLTerm && (sqlite3WhereTrace & 0x100)!=0 ){ int i; for(i=0; i<p->nLTerm; i++){ |
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3952 3953 3954 3955 3956 3957 3958 | ** relationship is inverted and needs to be adjusted. */ static int whereLoopCheaperProperSubset( const WhereLoop *pX, /* First WhereLoop to compare */ const WhereLoop *pY /* Compare against this WhereLoop */ ){ int i, j; | > | > > | 3952 3953 3954 3955 3956 3957 3958 3959 3960 3961 3962 3963 3964 3965 3966 3967 3968 3969 3970 3971 3972 3973 3974 | ** relationship is inverted and needs to be adjusted. */ static int whereLoopCheaperProperSubset( const WhereLoop *pX, /* First WhereLoop to compare */ const WhereLoop *pY /* Compare against this WhereLoop */ ){ int i, j; if( pX->nLTerm-pX->nSkip >= pY->nLTerm-pY->nSkip ){ return 0; /* X is not a subset of Y */ } if( pX->rRun >= pY->rRun ){ if( pX->rRun > pY->rRun ) return 0; /* X costs more than Y */ if( pX->nOut > pY->nOut ) return 0; /* X costs more than Y */ } for(i=pX->nLTerm-1; i>=0; i--){ if( pX->aLTerm[i]==0 ) continue; for(j=pY->nLTerm-1; j>=0; j--){ if( pY->aLTerm[j]==pX->aLTerm[i] ) break; } if( j<0 ) return 0; /* X not a subset of Y since term X[i] not used by Y */ } return 1; /* All conditions meet */ } |
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3979 3980 3981 3982 3983 3984 3985 | ** ** (2) pTemplate costs more than any other WhereLoops for which pTemplate ** is a proper subset. ** ** To say "WhereLoop X is a proper subset of Y" means that X uses fewer ** WHERE clause terms than Y and that every WHERE clause term used by X is ** also used by Y. | < < < < < < < < < < < < < | 3982 3983 3984 3985 3986 3987 3988 3989 3990 3991 3992 3993 3994 3995 3996 3997 3998 3999 4000 4001 | ** ** (2) pTemplate costs more than any other WhereLoops for which pTemplate ** is a proper subset. ** ** To say "WhereLoop X is a proper subset of Y" means that X uses fewer ** WHERE clause terms than Y and that every WHERE clause term used by X is ** also used by Y. */ static void whereLoopAdjustCost(const WhereLoop *p, WhereLoop *pTemplate){ if( (pTemplate->wsFlags & WHERE_INDEXED)==0 ) return; for(; p; p=p->pNextLoop){ if( p->iTab!=pTemplate->iTab ) continue; if( (p->wsFlags & WHERE_INDEXED)==0 ) continue; if( whereLoopCheaperProperSubset(p, pTemplate) ){ /* Adjust pTemplate cost downward so that it is cheaper than its ** subset p */ pTemplate->rRun = p->rRun; pTemplate->nOut = p->nOut - 1; }else if( whereLoopCheaperProperSubset(pTemplate, p) ){ /* Adjust pTemplate cost upward so that it is costlier than p since |
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4291 4292 4293 4294 4295 4296 4297 | WhereLoop *pNew; /* Template WhereLoop under construction */ WhereTerm *pTerm; /* A WhereTerm under consideration */ int opMask; /* Valid operators for constraints */ WhereScan scan; /* Iterator for WHERE terms */ Bitmask saved_prereq; /* Original value of pNew->prereq */ u16 saved_nLTerm; /* Original value of pNew->nLTerm */ u16 saved_nEq; /* Original value of pNew->u.btree.nEq */ | | | 4281 4282 4283 4284 4285 4286 4287 4288 4289 4290 4291 4292 4293 4294 4295 | WhereLoop *pNew; /* Template WhereLoop under construction */ WhereTerm *pTerm; /* A WhereTerm under consideration */ int opMask; /* Valid operators for constraints */ WhereScan scan; /* Iterator for WHERE terms */ Bitmask saved_prereq; /* Original value of pNew->prereq */ u16 saved_nLTerm; /* Original value of pNew->nLTerm */ u16 saved_nEq; /* Original value of pNew->u.btree.nEq */ u16 saved_nSkip; /* Original value of pNew->nSkip */ u32 saved_wsFlags; /* Original value of pNew->wsFlags */ LogEst saved_nOut; /* Original value of pNew->nOut */ int iCol; /* Index of the column in the table */ int rc = SQLITE_OK; /* Return code */ LogEst rSize; /* Number of rows in the table */ LogEst rLogSize; /* Logarithm of table size */ WhereTerm *pTop = 0, *pBtm = 0; /* Top and bottom range constraints */ |
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4320 4321 4322 4323 4324 4325 4326 | assert( pNew->u.btree.nEq<pProbe->nColumn ); iCol = pProbe->aiColumn[pNew->u.btree.nEq]; pTerm = whereScanInit(&scan, pBuilder->pWC, pSrc->iCursor, iCol, opMask, pProbe); saved_nEq = pNew->u.btree.nEq; | | < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < | 4310 4311 4312 4313 4314 4315 4316 4317 4318 4319 4320 4321 4322 4323 4324 4325 4326 4327 4328 4329 4330 4331 | assert( pNew->u.btree.nEq<pProbe->nColumn ); iCol = pProbe->aiColumn[pNew->u.btree.nEq]; pTerm = whereScanInit(&scan, pBuilder->pWC, pSrc->iCursor, iCol, opMask, pProbe); saved_nEq = pNew->u.btree.nEq; saved_nSkip = pNew->nSkip; saved_nLTerm = pNew->nLTerm; saved_wsFlags = pNew->wsFlags; saved_prereq = pNew->prereq; saved_nOut = pNew->nOut; pNew->rSetup = 0; rSize = pProbe->aiRowLogEst[0]; rLogSize = estLog(rSize); for(; rc==SQLITE_OK && pTerm!=0; pTerm = whereScanNext(&scan)){ u16 eOp = pTerm->eOperator; /* Shorthand for pTerm->eOperator */ LogEst rCostIdx; LogEst nOutUnadjusted; /* nOut before IN() and WHERE adjustments */ int nIn = 0; #ifdef SQLITE_ENABLE_STAT3_OR_STAT4 int nRecValid = pBuilder->nRecValid; |
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4528 4529 4530 4531 4532 4533 4534 | pNew->nOut = saved_nOut; #ifdef SQLITE_ENABLE_STAT3_OR_STAT4 pBuilder->nRecValid = nRecValid; #endif } pNew->prereq = saved_prereq; pNew->u.btree.nEq = saved_nEq; | | > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > | 4480 4481 4482 4483 4484 4485 4486 4487 4488 4489 4490 4491 4492 4493 4494 4495 4496 4497 4498 4499 4500 4501 4502 4503 4504 4505 4506 4507 4508 4509 4510 4511 4512 4513 4514 4515 4516 4517 4518 4519 4520 4521 4522 4523 4524 4525 4526 4527 4528 4529 4530 4531 4532 4533 4534 4535 4536 4537 | pNew->nOut = saved_nOut; #ifdef SQLITE_ENABLE_STAT3_OR_STAT4 pBuilder->nRecValid = nRecValid; #endif } pNew->prereq = saved_prereq; pNew->u.btree.nEq = saved_nEq; pNew->nSkip = saved_nSkip; pNew->wsFlags = saved_wsFlags; pNew->nOut = saved_nOut; pNew->nLTerm = saved_nLTerm; /* Consider using a skip-scan if there are no WHERE clause constraints ** available for the left-most terms of the index, and if the average ** number of repeats in the left-most terms is at least 18. ** ** The magic number 18 is selected on the basis that scanning 17 rows ** is almost always quicker than an index seek (even though if the index ** contains fewer than 2^17 rows we assume otherwise in other parts of ** the code). And, even if it is not, it should not be too much slower. ** On the other hand, the extra seeks could end up being significantly ** more expensive. */ assert( 42==sqlite3LogEst(18) ); if( saved_nEq==saved_nSkip && saved_nEq+1<pProbe->nKeyCol && pProbe->aiRowLogEst[saved_nEq+1]>=42 /* TUNING: Minimum for skip-scan */ && (rc = whereLoopResize(db, pNew, pNew->nLTerm+1))==SQLITE_OK ){ LogEst nIter; pNew->u.btree.nEq++; pNew->nSkip++; pNew->aLTerm[pNew->nLTerm++] = 0; pNew->wsFlags |= WHERE_SKIPSCAN; nIter = pProbe->aiRowLogEst[saved_nEq] - pProbe->aiRowLogEst[saved_nEq+1]; if( pTerm ){ /* TUNING: When estimating skip-scan for a term that is also indexable, ** multiply the cost of the skip-scan by 2.0, to make it a little less ** desirable than the regular index lookup. */ nIter += 10; assert( 10==sqlite3LogEst(2) ); } pNew->nOut -= nIter; /* TUNING: Because uncertainties in the estimates for skip-scan queries, ** add a 1.375 fudge factor to make skip-scan slightly less likely. */ nIter += 5; whereLoopAddBtreeIndex(pBuilder, pSrc, pProbe, nIter + nInMul); pNew->nOut = saved_nOut; pNew->u.btree.nEq = saved_nEq; pNew->nSkip = saved_nSkip; pNew->wsFlags = saved_wsFlags; } return rc; } /* ** Return True if it is possible that pIndex might be useful in ** implementing the ORDER BY clause in pBuilder. ** |
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4710 4711 4712 4713 4714 4715 4716 | /* Generate auto-index WhereLoops */ WhereTerm *pTerm; WhereTerm *pWCEnd = pWC->a + pWC->nTerm; for(pTerm=pWC->a; rc==SQLITE_OK && pTerm<pWCEnd; pTerm++){ if( pTerm->prereqRight & pNew->maskSelf ) continue; if( termCanDriveIndex(pTerm, pSrc, 0) ){ pNew->u.btree.nEq = 1; | | | 4702 4703 4704 4705 4706 4707 4708 4709 4710 4711 4712 4713 4714 4715 4716 | /* Generate auto-index WhereLoops */ WhereTerm *pTerm; WhereTerm *pWCEnd = pWC->a + pWC->nTerm; for(pTerm=pWC->a; rc==SQLITE_OK && pTerm<pWCEnd; pTerm++){ if( pTerm->prereqRight & pNew->maskSelf ) continue; if( termCanDriveIndex(pTerm, pSrc, 0) ){ pNew->u.btree.nEq = 1; pNew->nSkip = 0; pNew->u.btree.pIndex = 0; pNew->nLTerm = 1; pNew->aLTerm[0] = pTerm; /* TUNING: One-time cost for computing the automatic index is ** estimated to be X*N*log2(N) where N is the number of rows in ** the table being indexed and where X is 7 (LogEst=28) for normal ** tables or 1.375 (LogEst=4) for views and subqueries. The value |
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4751 4752 4753 4754 4755 4756 4757 | if( pProbe->pPartIdxWhere!=0 && !whereUsablePartialIndex(pSrc->iCursor, pWC, pProbe->pPartIdxWhere) ){ testcase( pNew->iTab!=pSrc->iCursor ); /* See ticket [98d973b8f5] */ continue; /* Partial index inappropriate for this query */ } rSize = pProbe->aiRowLogEst[0]; pNew->u.btree.nEq = 0; | | | 4743 4744 4745 4746 4747 4748 4749 4750 4751 4752 4753 4754 4755 4756 4757 | if( pProbe->pPartIdxWhere!=0 && !whereUsablePartialIndex(pSrc->iCursor, pWC, pProbe->pPartIdxWhere) ){ testcase( pNew->iTab!=pSrc->iCursor ); /* See ticket [98d973b8f5] */ continue; /* Partial index inappropriate for this query */ } rSize = pProbe->aiRowLogEst[0]; pNew->u.btree.nEq = 0; pNew->nSkip = 0; pNew->nLTerm = 0; pNew->iSortIdx = 0; pNew->rSetup = 0; pNew->prereq = mExtra; pNew->nOut = rSize; pNew->u.btree.pIndex = pProbe; b = indexMightHelpWithOrderBy(pBuilder, pProbe, pSrc->iCursor); |
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5301 5302 5303 5304 5305 5306 5307 | rev = revSet = 0; distinctColumns = 0; for(j=0; j<nColumn; j++){ u8 bOnce; /* True to run the ORDER BY search loop */ /* Skip over == and IS NULL terms */ if( j<pLoop->u.btree.nEq | | | 5293 5294 5295 5296 5297 5298 5299 5300 5301 5302 5303 5304 5305 5306 5307 | rev = revSet = 0; distinctColumns = 0; for(j=0; j<nColumn; j++){ u8 bOnce; /* True to run the ORDER BY search loop */ /* Skip over == and IS NULL terms */ if( j<pLoop->u.btree.nEq && pLoop->nSkip==0 && ((i = pLoop->aLTerm[j]->eOperator) & (WO_EQ|WO_ISNULL))!=0 ){ if( i & WO_ISNULL ){ testcase( isOrderDistinct ); isOrderDistinct = 0; } continue; |
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5874 5875 5876 5877 5878 5879 5880 | pTab = pItem->pTab; if( IsVirtual(pTab) ) return 0; if( pItem->zIndex ) return 0; iCur = pItem->iCursor; pWC = &pWInfo->sWC; pLoop = pBuilder->pNew; pLoop->wsFlags = 0; | | < | 5866 5867 5868 5869 5870 5871 5872 5873 5874 5875 5876 5877 5878 5879 5880 5881 5882 5883 5884 5885 5886 5887 5888 5889 5890 5891 | pTab = pItem->pTab; if( IsVirtual(pTab) ) return 0; if( pItem->zIndex ) return 0; iCur = pItem->iCursor; pWC = &pWInfo->sWC; pLoop = pBuilder->pNew; pLoop->wsFlags = 0; pLoop->nSkip = 0; pTerm = findTerm(pWC, iCur, -1, 0, WO_EQ, 0); if( pTerm ){ pLoop->wsFlags = WHERE_COLUMN_EQ|WHERE_IPK|WHERE_ONEROW; pLoop->aLTerm[0] = pTerm; pLoop->nLTerm = 1; pLoop->u.btree.nEq = 1; /* TUNING: Cost of a rowid lookup is 10 */ pLoop->rRun = 33; /* 33==sqlite3LogEst(10) */ }else{ for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){ assert( pLoop->aLTermSpace==pLoop->aLTerm ); if( !IsUniqueIndex(pIdx) || pIdx->pPartIdxWhere!=0 || pIdx->nKeyCol>ArraySize(pLoop->aLTermSpace) ) continue; for(j=0; j<pIdx->nKeyCol; j++){ pTerm = findTerm(pWC, iCur, pIdx->aiColumn[j], 0, WO_EQ, pIdx); if( pTerm==0 ) break; |
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Changes to src/whereInt.h.
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111 112 113 114 115 116 117 | u8 iSortIdx; /* Sorting index number. 0==None */ LogEst rSetup; /* One-time setup cost (ex: create transient index) */ LogEst rRun; /* Cost of running each loop */ LogEst nOut; /* Estimated number of output rows */ union { struct { /* Information for internal btree tables */ u16 nEq; /* Number of equality constraints */ | < > | | 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 | u8 iSortIdx; /* Sorting index number. 0==None */ LogEst rSetup; /* One-time setup cost (ex: create transient index) */ LogEst rRun; /* Cost of running each loop */ LogEst nOut; /* Estimated number of output rows */ union { struct { /* Information for internal btree tables */ u16 nEq; /* Number of equality constraints */ Index *pIndex; /* Index used, or NULL */ } btree; struct { /* Information for virtual tables */ int idxNum; /* Index number */ u8 needFree; /* True if sqlite3_free(idxStr) is needed */ i8 isOrdered; /* True if satisfies ORDER BY */ u16 omitMask; /* Terms that may be omitted */ char *idxStr; /* Index identifier string */ } vtab; } u; u32 wsFlags; /* WHERE_* flags describing the plan */ u16 nLTerm; /* Number of entries in aLTerm[] */ u16 nSkip; /* Number of NULL aLTerm[] entries */ /**** whereLoopXfer() copies fields above ***********************/ # define WHERE_LOOP_XFER_SZ offsetof(WhereLoop,nLSlot) u16 nLSlot; /* Number of slots allocated for aLTerm[] */ WhereTerm **aLTerm; /* WhereTerms used */ WhereLoop *pNextLoop; /* Next WhereLoop object in the WhereClause */ WhereTerm *aLTermSpace[3]; /* Initial aLTerm[] space */ }; /* This object holds the prerequisites and the cost of running a ** subquery on one operand of an OR operator in the WHERE clause. ** See WhereOrSet for additional information */ struct WhereOrCost { |
︙ | ︙ |
Added test/skipscan6.test.
> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 | # 2014-10-21 # # The author disclaims copyright to this source code. In place of # a legal notice, here is a blessing: # # May you do good and not evil. # May you find forgiveness for yourself and forgive others. # May you share freely, never taking more than you give. # #*********************************************************************** # # This file implements tests of the "skip-scan" query strategy. In # particular, this file verifies that use of all columns of an index # is always preferred over the use of a skip-scan on some columns of # the same index. Because of difficulties in scoring a skip-scan, # the skip-scan can sometimes come out with a lower raw score when # using STAT4. But the query planner should detect this and use the # full index rather than the skip-scan. # set testdir [file dirname $argv0] source $testdir/tester.tcl set testprefix skipscan6 ifcapable !stat4 { finish_test return } do_execsql_test 1.1 { CREATE TABLE t1( aa int, bb int, cc int, dd int, ee int ); CREATE INDEX ix on t1(aa, bb, cc, dd DESC); ANALYZE sqlite_master; INSERT INTO sqlite_stat1 VALUES('t1','ix','2695116 1347558 264 18 2'); INSERT INTO sqlite_stat4 VALUES('t1','ix','2677151 196859 196859 32 1','0 15043 15043 92468 92499','0 19 286 81846 92499',X'0609010804031552977BD725BD28'); INSERT INTO sqlite_stat4 VALUES('t1','ix','2677151 14687 161 1 1','0 289067 299306 299457 299457','0 199 6772 273984 299457',X'060902020403013406314D67456415B819'); INSERT INTO sqlite_stat4 VALUES('t1','ix','2677151 19313 19308 22 1','0 325815 325815 343725 343746','0 261 9545 315009 343746',X'060902080403018A49B0A3AD1ED931'); INSERT INTO sqlite_stat4 VALUES('t1','ix','2677151 25047 9051 15 1','0 350443 350443 356590 356604','0 266 9795 325519 356604',X'06090208040301914C2DD2E91F93CF'); INSERT INTO sqlite_stat4 VALUES('t1','ix','2677151 42327 9906 7 1','0 376381 376381 380291 380297','0 268 10100 344232 380297',X'06090208040301934BF672511F7ED3'); INSERT INTO sqlite_stat4 VALUES('t1','ix','2677151 24513 2237 1 1','0 455150 467779 470015 470015','0 286 10880 425401 470015',X'06090202040301A703464A28F2611EF1EE'); INSERT INTO sqlite_stat4 VALUES('t1','ix','2677151 18730 18724 15 1','0 479663 479663 498271 498285','0 287 10998 450793 498285',X'06090208040301A8494AF3A41EC50C'); INSERT INTO sqlite_stat4 VALUES('t1','ix','2677151 119603 47125 1 1','0 572425 572425 598915 598915','0 404 14230 546497 598915',X'06090208040302474FD1929A03194F'); INSERT INTO sqlite_stat4 VALUES('t1','ix','2677151 1454 1454 1 1','0 898346 898346 898373 898373','0 952 31165 827562 898373',X'06090208040304FD53F6A2A2097F64'); INSERT INTO sqlite_stat4 VALUES('t1','ix','2677151 57138 7069 1 1','0 1122389 1122389 1129457 1129457','0 1967 46801 1045943 1129457',X'06090208040309884BC4C52F1F6EB7'); INSERT INTO sqlite_stat4 VALUES('t1','ix','2677151 285 11 1 1','0 1197683 1197824 1197831 1197831','0 2033 50990 1112280 1197831',X'06090202040309D80346503FE2A9038E4F'); INSERT INTO sqlite_stat4 VALUES('t1','ix','2677151 25365 9773 1 1','0 1301013 1301013 1310785 1310785','0 2561 58806 1217877 1310785',X'0609020804030C5F4C8F88AB0AF2A2'); INSERT INTO sqlite_stat4 VALUES('t1','ix','2677151 45180 7222 1 1','0 1326378 1326378 1333599 1333599','0 2562 59921 1240187 1333599',X'0609020804030C604CAB75490B0351'); INSERT INTO sqlite_stat4 VALUES('t1','ix','2677151 8537 41 1 1','0 1496959 1497288 1497289 1497289','0 3050 68246 1394126 1497289',X'0609020204030EA0057F527459B0257C4B'); INSERT INTO sqlite_stat4 VALUES('t1','ix','2677151 26139 26131 17 1','0 1507977 1507977 1520578 1520594','0 3074 69188 1416111 1520594',X'0609020804030EB95169453423D4EA'); INSERT INTO sqlite_stat4 VALUES('t1','ix','2677151 102894 29678 1 1','0 1537421 1550467 1564894 1564894','0 3109 69669 1459820 1564894',X'0609020204030EE3183652A6ED3006EBCB'); INSERT INTO sqlite_stat4 VALUES('t1','ix','2677151 319 3 1 1','0 1796728 1796746 1796747 1796747','0 3650 86468 1682243 1796747',X'0609020204031163033550D0C41018C28D'); INSERT INTO sqlite_stat4 VALUES('t1','ix','2677151 127 127 1 1','0 2096194 2096194 2096205 2096205','0 5145 106437 1951535 2096205',X'060902080403180F53BB1AF727EE50'); INSERT INTO sqlite_stat4 VALUES('t1','ix','2677151 66574 5252 1 1','0 2230524 2265961 2271212 2271212','0 5899 114976 2085829 2271212',X'0609020204031B8A05195009976D223B90'); INSERT INTO sqlite_stat4 VALUES('t1','ix','2677151 19440 19440 1 1','0 2391680 2391680 2395663 2395663','0 6718 123714 2184781 2395663',X'0609020804031F7452E00A7B07431A'); INSERT INTO sqlite_stat4 VALUES('t1','ix','2677151 18321 2177 1 1','0 2522928 2523231 2525407 2525407','0 7838 139084 2299958 2525407',X'06090201040324A7475231103B1AA7B8'); INSERT INTO sqlite_stat4 VALUES('t1','ix','2677151 22384 1361 1 1','0 2541249 2544834 2546194 2546194','0 7839 139428 2308416 2546194',X'06090202040324A8011652323D4B1AA9EB'); INSERT INTO sqlite_stat4 VALUES('t1','ix','2677151 18699 855 1 1','0 2563633 2578178 2579032 2579032','0 7840 139947 2321671 2579032',X'06090202040324A9077452323D7D1052C5'); INSERT INTO sqlite_stat4 VALUES('t1','ix','17965 1579 1579 1 1','2677151 2690666 2690666 2692244 2692244','1 9870 153959 2418294 2692244',X'060102080403021B8A4FE1AB84032B35'); ANALYZE sqlite_master; } {} do_execsql_test 1.2 { EXPLAIN QUERY PLAN SELECT COUNT(*) FROM t1 WHERE bb=21 AND aa=1 AND dd BETWEEN 1413833728 and 1413837331; } {/INDEX ix .aa=. AND bb=../} do_execsql_test 2.1 { DROP INDEX ix; CREATE INDEX good on t1(bb, aa, dd DESC); CREATE INDEX bad on t1(aa, bb, cc, dd DESC); DELETE FROM sqlite_stat1; DELETE FROM sqlite_stat4; INSERT INTO sqlite_stat1 VALUES('t1','good','2695116 299 264 2'); INSERT INTO sqlite_stat1 VALUES('t1','bad','2695116 1347558 264 18 2'); INSERT INTO sqlite_stat4 VALUES('t1','good','197030 196859 32 1','15086 15086 92511 92536','19 25 81644 92536',X'05010904031552977BD725BD22'); INSERT INTO sqlite_stat4 VALUES('t1','good','14972 14687 1 1','289878 289878 299457 299457','199 244 267460 299457',X'050209040301344F7E569402C419'); INSERT INTO sqlite_stat4 VALUES('t1','good','19600 19313 22 1','327127 327127 346222 346243','261 319 306884 346243',X'0502090403018A49503BC01EC577'); INSERT INTO sqlite_stat4 VALUES('t1','good','25666 25047 15 1','352087 352087 372692 372706','266 327 325601 372706',X'050209040301914C2DD2E91F93CF'); INSERT INTO sqlite_stat4 VALUES('t1','good','42392 42327 26 1','378657 378657 382547 382572','268 331 333529 382572',X'05020904030193533B2FE326ED48'); INSERT INTO sqlite_stat4 VALUES('t1','good','24619 24513 11 1','457872 457872 461748 461758','286 358 399322 461758',X'050209040301A752B1557825EA7C'); INSERT INTO sqlite_stat4 VALUES('t1','good','18969 18730 15 1','482491 482491 501105 501119','287 360 433605 501119',X'050209040301A8494AF3A41EC50C'); INSERT INTO sqlite_stat4 VALUES('t1','good','119710 119603 1 1','576500 576500 598915 598915','404 505 519877 598915',X'05020904030247539A7A7912F617'); INSERT INTO sqlite_stat4 VALUES('t1','good','11955 11946 1 1','889796 889796 898373 898373','938 1123 794694 898373',X'050209040304EF4DF9C4150BBB28'); INSERT INTO sqlite_stat4 VALUES('t1','good','57197 57138 24 1','1129865 1129865 1151492 1151515','1967 2273 1027048 1151515',X'05020904030988533510BC26E20A'); INSERT INTO sqlite_stat4 VALUES('t1','good','3609 3543 1 1','1196265 1196265 1197831 1197831','2002 2313 1070108 1197831',X'050209040309B050E95CD718D94D'); INSERT INTO sqlite_stat4 VALUES('t1','good','25391 25365 13 1','1309378 1309378 1315567 1315579','2561 2936 1178358 1315579',X'05020904030C5F53DF9E13283570'); INSERT INTO sqlite_stat4 VALUES('t1','good','45232 45180 17 1','1334769 1334769 1337946 1337962','2562 2938 1198998 1337962',X'05020904030C60541CACEE28BCAC'); INSERT INTO sqlite_stat4 VALUES('t1','good','5496 5493 1 1','1495882 1495882 1497289 1497289','3043 3479 1348695 1497289',X'05020904030E99515C62AD0F0B34'); INSERT INTO sqlite_stat4 VALUES('t1','good','26348 26139 17 1','1517381 1517381 1529990 1530006','3074 3519 1378320 1530006',X'05020904030EB95169453423D4EA'); INSERT INTO sqlite_stat4 VALUES('t1','good','102927 102894 10 1','1547088 1547088 1649950 1649959','3109 3559 1494260 1649959',X'05020904030EE34D309F671FFA47'); INSERT INTO sqlite_stat4 VALUES('t1','good','3602 3576 1 1','1793873 1793873 1796747 1796747','3601 4128 1630783 1796747',X'050209040311294FE88B432219B9'); INSERT INTO sqlite_stat4 VALUES('t1','good','154 154 1 1','2096059 2096059 2096205 2096205','5037 5779 1893039 2096205',X'050209040317994EFF05A016DCED'); INSERT INTO sqlite_stat4 VALUES('t1','good','68153 66574 60 1','2244039 2244039 2268892 2268951','5899 6749 2027553 2268951',X'05020904031B8A532DBC5A26D2BA'); INSERT INTO sqlite_stat4 VALUES('t1','good','321 321 1 1','2395618 2395618 2395663 2395663','6609 7528 2118435 2395663',X'05020904031EFA54078EEE1E2D65'); INSERT INTO sqlite_stat4 VALUES('t1','good','19449 19440 22 1','2407769 2407769 2426049 2426070','6718 7651 2146904 2426070',X'05020904031F7450E6118C2336BD'); INSERT INTO sqlite_stat4 VALUES('t1','good','18383 18321 56 1','2539949 2539949 2551080 2551135','7838 8897 2245459 2551135',X'050209040324A752EA2E1E2642B2'); INSERT INTO sqlite_stat4 VALUES('t1','good','22479 22384 60 1','2558332 2558332 2565233 2565292','7839 8899 2251202 2565292',X'050209040324A853926538279A5F'); INSERT INTO sqlite_stat4 VALUES('t1','good','18771 18699 63 1','2580811 2580811 2596914 2596976','7840 8901 2263572 2596976',X'050209040324A9526C1DE9256E72'); INSERT INTO sqlite_stat4 VALUES('t1','bad','2677151 196859 196859 32 1','0 15043 15043 92468 92499','0 19 286 81846 92499',X'0609010804031552977BD725BD28'); INSERT INTO sqlite_stat4 VALUES('t1','bad','2677151 14687 161 1 1','0 289067 299306 299457 299457','0 199 6772 273984 299457',X'060902020403013406314D67456415B819'); INSERT INTO sqlite_stat4 VALUES('t1','bad','2677151 19313 19308 22 1','0 325815 325815 343725 343746','0 261 9545 315009 343746',X'060902080403018A49B0A3AD1ED931'); INSERT INTO sqlite_stat4 VALUES('t1','bad','2677151 25047 9051 15 1','0 350443 350443 356590 356604','0 266 9795 325519 356604',X'06090208040301914C2DD2E91F93CF'); INSERT INTO sqlite_stat4 VALUES('t1','bad','2677151 42327 9906 7 1','0 376381 376381 380291 380297','0 268 10100 344232 380297',X'06090208040301934BF672511F7ED3'); INSERT INTO sqlite_stat4 VALUES('t1','bad','2677151 24513 2237 1 1','0 455150 467779 470015 470015','0 286 10880 425401 470015',X'06090202040301A703464A28F2611EF1EE'); INSERT INTO sqlite_stat4 VALUES('t1','bad','2677151 18730 18724 15 1','0 479663 479663 498271 498285','0 287 10998 450793 498285',X'06090208040301A8494AF3A41EC50C'); INSERT INTO sqlite_stat4 VALUES('t1','bad','2677151 119603 47125 1 1','0 572425 572425 598915 598915','0 404 14230 546497 598915',X'06090208040302474FD1929A03194F'); INSERT INTO sqlite_stat4 VALUES('t1','bad','2677151 1454 1454 1 1','0 898346 898346 898373 898373','0 952 31165 827562 898373',X'06090208040304FD53F6A2A2097F64'); INSERT INTO sqlite_stat4 VALUES('t1','bad','2677151 57138 7069 1 1','0 1122389 1122389 1129457 1129457','0 1967 46801 1045943 1129457',X'06090208040309884BC4C52F1F6EB7'); INSERT INTO sqlite_stat4 VALUES('t1','bad','2677151 285 11 1 1','0 1197683 1197824 1197831 1197831','0 2033 50990 1112280 1197831',X'06090202040309D80346503FE2A9038E4F'); INSERT INTO sqlite_stat4 VALUES('t1','bad','2677151 25365 9773 1 1','0 1301013 1301013 1310785 1310785','0 2561 58806 1217877 1310785',X'0609020804030C5F4C8F88AB0AF2A2'); INSERT INTO sqlite_stat4 VALUES('t1','bad','2677151 45180 7222 1 1','0 1326378 1326378 1333599 1333599','0 2562 59921 1240187 1333599',X'0609020804030C604CAB75490B0351'); INSERT INTO sqlite_stat4 VALUES('t1','bad','2677151 8537 41 1 1','0 1496959 1497288 1497289 1497289','0 3050 68246 1394126 1497289',X'0609020204030EA0057F527459B0257C4B'); INSERT INTO sqlite_stat4 VALUES('t1','bad','2677151 26139 26131 17 1','0 1507977 1507977 1520578 1520594','0 3074 69188 1416111 1520594',X'0609020804030EB95169453423D4EA'); INSERT INTO sqlite_stat4 VALUES('t1','bad','2677151 102894 29678 1 1','0 1537421 1550467 1564894 1564894','0 3109 69669 1459820 1564894',X'0609020204030EE3183652A6ED3006EBCB'); INSERT INTO sqlite_stat4 VALUES('t1','bad','2677151 319 3 1 1','0 1796728 1796746 1796747 1796747','0 3650 86468 1682243 1796747',X'0609020204031163033550D0C41018C28D'); INSERT INTO sqlite_stat4 VALUES('t1','bad','2677151 127 127 1 1','0 2096194 2096194 2096205 2096205','0 5145 106437 1951535 2096205',X'060902080403180F53BB1AF727EE50'); INSERT INTO sqlite_stat4 VALUES('t1','bad','2677151 66574 5252 1 1','0 2230524 2265961 2271212 2271212','0 5899 114976 2085829 2271212',X'0609020204031B8A05195009976D223B90'); INSERT INTO sqlite_stat4 VALUES('t1','bad','2677151 19440 19440 1 1','0 2391680 2391680 2395663 2395663','0 6718 123714 2184781 2395663',X'0609020804031F7452E00A7B07431A'); INSERT INTO sqlite_stat4 VALUES('t1','bad','2677151 18321 2177 1 1','0 2522928 2523231 2525407 2525407','0 7838 139084 2299958 2525407',X'06090201040324A7475231103B1AA7B8'); INSERT INTO sqlite_stat4 VALUES('t1','bad','2677151 22384 1361 1 1','0 2541249 2544834 2546194 2546194','0 7839 139428 2308416 2546194',X'06090202040324A8011652323D4B1AA9EB'); INSERT INTO sqlite_stat4 VALUES('t1','bad','2677151 18699 855 1 1','0 2563633 2578178 2579032 2579032','0 7840 139947 2321671 2579032',X'06090202040324A9077452323D7D1052C5'); INSERT INTO sqlite_stat4 VALUES('t1','bad','17965 1579 1579 1 1','2677151 2690666 2690666 2692244 2692244','1 9870 153959 2418294 2692244',X'060102080403021B8A4FE1AB84032B35'); ANALYZE sqlite_master; } {} do_execsql_test 2.2 { EXPLAIN QUERY PLAN SELECT COUNT(*) FROM t1 WHERE bb=21 AND aa=1 AND dd BETWEEN 1413833728 and 1413837331; } {/INDEX good .bb=. AND aa=. AND dd>. AND dd<../} finish_test |