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Overview
Comment: | Make the partial-ORDER-BY information in the query planner available to the SELECT code generator. Still doesn't make a difference in the generated code. |
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Downloads: | Tarball | ZIP archive |
Timelines: | family | ancestors | descendants | both | orderby-planning |
Files: | files | file ages | folders |
SHA1: |
e258df236b7de70087c8227cb209080e |
User & Date: | drh 2014-03-18 20:33:42.067 |
Context
2014-03-19
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14:10 | First attempt at getting block-sort to work. This is an incremental check-in. There are many problems still to be worked out. (check-in: 59742dd4c5 user: drh tags: orderby-planning) | |
2014-03-18
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20:33 | Make the partial-ORDER-BY information in the query planner available to the SELECT code generator. Still doesn't make a difference in the generated code. (check-in: e258df236b user: drh tags: orderby-planning) | |
18:59 | Adjust the query planner to keep track of the number of ORDER BY terms satisfied. Still doesn't do anything with this information. Some tests fail after this check-in, but all failures are believed to be benign. The failures will be addressed at a later stage. (check-in: 59d49b7fc4 user: drh tags: orderby-planning) | |
Changes
Changes to src/select.c.
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558 559 560 561 562 563 564 565 566 567 568 569 570 571 | */ static void selectInnerLoop( Parse *pParse, /* The parser context */ Select *p, /* The complete select statement being coded */ ExprList *pEList, /* List of values being extracted */ int srcTab, /* Pull data from this table */ ExprList *pOrderBy, /* If not NULL, sort results using this key */ DistinctCtx *pDistinct, /* If not NULL, info on how to process DISTINCT */ SelectDest *pDest, /* How to dispose of the results */ int iContinue, /* Jump here to continue with next row */ int iBreak /* Jump here to break out of the inner loop */ ){ Vdbe *v = pParse->pVdbe; int i; | > | 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 | */ static void selectInnerLoop( Parse *pParse, /* The parser context */ Select *p, /* The complete select statement being coded */ ExprList *pEList, /* List of values being extracted */ int srcTab, /* Pull data from this table */ ExprList *pOrderBy, /* If not NULL, sort results using this key */ int nOBSat, /* Terms of ORDER BY already satisfied */ DistinctCtx *pDistinct, /* If not NULL, info on how to process DISTINCT */ SelectDest *pDest, /* How to dispose of the results */ int iContinue, /* Jump here to continue with next row */ int iBreak /* Jump here to break out of the inner loop */ ){ Vdbe *v = pParse->pVdbe; int i; |
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1050 1051 1052 1053 1054 1055 1056 | ** then the results were placed in a sorter. After the loop is terminated ** we need to run the sorter and output the results. The following ** routine generates the code needed to do that. */ static void generateSortTail( Parse *pParse, /* Parsing context */ Select *p, /* The SELECT statement */ | < > | 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 | ** then the results were placed in a sorter. After the loop is terminated ** we need to run the sorter and output the results. The following ** routine generates the code needed to do that. */ static void generateSortTail( Parse *pParse, /* Parsing context */ Select *p, /* The SELECT statement */ int nColumn, /* Number of columns of data */ SelectDest *pDest /* Write the sorted results here */ ){ Vdbe *v = pParse->pVdbe; /* The prepared statement */ int addrBreak = sqlite3VdbeMakeLabel(v); /* Jump here to exit loop */ int addrContinue = sqlite3VdbeMakeLabel(v); /* Jump here for next cycle */ int addr; int iTab; int pseudoTab = 0; ExprList *pOrderBy = p->pOrderBy; |
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1914 1915 1916 1917 1918 1919 1920 | } sqlite3VdbeAddOp1(v, OP_Delete, iQueue); /* Output the single row in Current */ addrCont = sqlite3VdbeMakeLabel(v); codeOffset(v, regOffset, addrCont); selectInnerLoop(pParse, p, p->pEList, iCurrent, | | | 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 | } sqlite3VdbeAddOp1(v, OP_Delete, iQueue); /* Output the single row in Current */ addrCont = sqlite3VdbeMakeLabel(v); codeOffset(v, regOffset, addrCont); selectInnerLoop(pParse, p, p->pEList, iCurrent, 0, 0, 0, pDest, addrCont, addrBreak); if( regLimit ){ sqlite3VdbeAddOp3(v, OP_IfZero, regLimit, addrBreak, -1); VdbeCoverage(v); } sqlite3VdbeResolveLabel(v, addrCont); /* Execute the recursive SELECT taking the single row in Current as |
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2188 2189 2190 2191 2192 2193 2194 | } iBreak = sqlite3VdbeMakeLabel(v); iCont = sqlite3VdbeMakeLabel(v); computeLimitRegisters(pParse, p, iBreak); sqlite3VdbeAddOp2(v, OP_Rewind, unionTab, iBreak); VdbeCoverage(v); iStart = sqlite3VdbeCurrentAddr(v); selectInnerLoop(pParse, p, p->pEList, unionTab, | | | 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200 2201 2202 2203 | } iBreak = sqlite3VdbeMakeLabel(v); iCont = sqlite3VdbeMakeLabel(v); computeLimitRegisters(pParse, p, iBreak); sqlite3VdbeAddOp2(v, OP_Rewind, unionTab, iBreak); VdbeCoverage(v); iStart = sqlite3VdbeCurrentAddr(v); selectInnerLoop(pParse, p, p->pEList, unionTab, 0, 0, 0, &dest, iCont, iBreak); sqlite3VdbeResolveLabel(v, iCont); sqlite3VdbeAddOp2(v, OP_Next, unionTab, iStart); VdbeCoverage(v); sqlite3VdbeResolveLabel(v, iBreak); sqlite3VdbeAddOp2(v, OP_Close, unionTab, 0); } break; } |
︙ | ︙ | |||
2266 2267 2268 2269 2270 2271 2272 | computeLimitRegisters(pParse, p, iBreak); sqlite3VdbeAddOp2(v, OP_Rewind, tab1, iBreak); VdbeCoverage(v); r1 = sqlite3GetTempReg(pParse); iStart = sqlite3VdbeAddOp2(v, OP_RowKey, tab1, r1); sqlite3VdbeAddOp4Int(v, OP_NotFound, tab2, iCont, r1, 0); VdbeCoverage(v); sqlite3ReleaseTempReg(pParse, r1); selectInnerLoop(pParse, p, p->pEList, tab1, | | | 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 | computeLimitRegisters(pParse, p, iBreak); sqlite3VdbeAddOp2(v, OP_Rewind, tab1, iBreak); VdbeCoverage(v); r1 = sqlite3GetTempReg(pParse); iStart = sqlite3VdbeAddOp2(v, OP_RowKey, tab1, r1); sqlite3VdbeAddOp4Int(v, OP_NotFound, tab2, iCont, r1, 0); VdbeCoverage(v); sqlite3ReleaseTempReg(pParse, r1); selectInnerLoop(pParse, p, p->pEList, tab1, 0, 0, 0, &dest, iCont, iBreak); sqlite3VdbeResolveLabel(v, iCont); sqlite3VdbeAddOp2(v, OP_Next, tab1, iStart); VdbeCoverage(v); sqlite3VdbeResolveLabel(v, iBreak); sqlite3VdbeAddOp2(v, OP_Close, tab2, 0); sqlite3VdbeAddOp2(v, OP_Close, tab1, 0); break; } |
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4726 4727 4728 4729 4730 4731 4732 4733 4734 4735 4736 4737 4738 4739 4740 4741 4742 4743 | }else{ sDistinct.eTnctType = WHERE_DISTINCT_NOOP; } if( !isAgg && pGroupBy==0 ){ /* No aggregate functions and no GROUP BY clause */ u16 wctrlFlags = (sDistinct.isTnct ? WHERE_WANT_DISTINCT : 0); /* Begin the database scan. */ pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, pOrderBy, p->pEList, wctrlFlags, 0); if( pWInfo==0 ) goto select_end; if( sqlite3WhereOutputRowCount(pWInfo) < p->nSelectRow ){ p->nSelectRow = sqlite3WhereOutputRowCount(pWInfo); } if( sDistinct.isTnct && sqlite3WhereIsDistinct(pWInfo) ){ sDistinct.eTnctType = sqlite3WhereIsDistinct(pWInfo); } | > | > | | 4727 4728 4729 4730 4731 4732 4733 4734 4735 4736 4737 4738 4739 4740 4741 4742 4743 4744 4745 4746 4747 4748 4749 4750 4751 4752 4753 4754 4755 4756 4757 4758 4759 4760 4761 4762 4763 4764 4765 4766 | }else{ sDistinct.eTnctType = WHERE_DISTINCT_NOOP; } if( !isAgg && pGroupBy==0 ){ /* No aggregate functions and no GROUP BY clause */ u16 wctrlFlags = (sDistinct.isTnct ? WHERE_WANT_DISTINCT : 0); int nOBSat; /* Begin the database scan. */ pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, pOrderBy, p->pEList, wctrlFlags, 0); if( pWInfo==0 ) goto select_end; if( sqlite3WhereOutputRowCount(pWInfo) < p->nSelectRow ){ p->nSelectRow = sqlite3WhereOutputRowCount(pWInfo); } if( sDistinct.isTnct && sqlite3WhereIsDistinct(pWInfo) ){ sDistinct.eTnctType = sqlite3WhereIsDistinct(pWInfo); } nOBSat = sqlite3WhereIsOrdered(pWInfo); if( pOrderBy && nOBSat==pOrderBy->nExpr ){ pOrderBy = 0; nOBSat = 0; } /* If sorting index that was created by a prior OP_OpenEphemeral ** instruction ended up not being needed, then change the OP_OpenEphemeral ** into an OP_Noop. */ if( addrSortIndex>=0 && pOrderBy==0 ){ sqlite3VdbeChangeToNoop(v, addrSortIndex); p->addrOpenEphm[2] = -1; } /* Use the standard inner loop. */ selectInnerLoop(pParse, p, pEList, -1, pOrderBy, nOBSat, &sDistinct, pDest, sqlite3WhereContinueLabel(pWInfo), sqlite3WhereBreakLabel(pWInfo)); /* End the database scan loop. */ sqlite3WhereEnd(pWInfo); }else{ |
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4871 4872 4873 4874 4875 4876 4877 | ** it might be a single loop that uses an index to extract information ** in the right order to begin with. */ sqlite3VdbeAddOp2(v, OP_Gosub, regReset, addrReset); pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, pGroupBy, 0, WHERE_GROUPBY, 0); if( pWInfo==0 ) goto select_end; | | | 4874 4875 4876 4877 4878 4879 4880 4881 4882 4883 4884 4885 4886 4887 4888 | ** it might be a single loop that uses an index to extract information ** in the right order to begin with. */ sqlite3VdbeAddOp2(v, OP_Gosub, regReset, addrReset); pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, pGroupBy, 0, WHERE_GROUPBY, 0); if( pWInfo==0 ) goto select_end; if( sqlite3WhereIsOrdered(pWInfo)==pGroupBy->nExpr ){ /* The optimizer is able to deliver rows in group by order so ** we do not have to sort. The OP_OpenEphemeral table will be ** cancelled later because we still need to use the pKeyInfo */ groupBySort = 0; }else{ /* Rows are coming out in undetermined order. We have to push |
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5022 5023 5024 5025 5026 5027 5028 | sqlite3VdbeResolveLabel(v, addrOutputRow); addrOutputRow = sqlite3VdbeCurrentAddr(v); sqlite3VdbeAddOp2(v, OP_IfPos, iUseFlag, addrOutputRow+2); VdbeCoverage(v); VdbeComment((v, "Groupby result generator entry point")); sqlite3VdbeAddOp1(v, OP_Return, regOutputRow); finalizeAggFunctions(pParse, &sAggInfo); sqlite3ExprIfFalse(pParse, pHaving, addrOutputRow+1, SQLITE_JUMPIFNULL); | | | 5025 5026 5027 5028 5029 5030 5031 5032 5033 5034 5035 5036 5037 5038 5039 | sqlite3VdbeResolveLabel(v, addrOutputRow); addrOutputRow = sqlite3VdbeCurrentAddr(v); sqlite3VdbeAddOp2(v, OP_IfPos, iUseFlag, addrOutputRow+2); VdbeCoverage(v); VdbeComment((v, "Groupby result generator entry point")); sqlite3VdbeAddOp1(v, OP_Return, regOutputRow); finalizeAggFunctions(pParse, &sAggInfo); sqlite3ExprIfFalse(pParse, pHaving, addrOutputRow+1, SQLITE_JUMPIFNULL); selectInnerLoop(pParse, p, p->pEList, -1, pOrderBy, 0, &sDistinct, pDest, addrOutputRow+1, addrSetAbort); sqlite3VdbeAddOp1(v, OP_Return, regOutputRow); VdbeComment((v, "end groupby result generator")); /* Generate a subroutine that will reset the group-by accumulator */ |
︙ | ︙ | |||
5154 5155 5156 5157 5158 5159 5160 | pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, pMinMax,0,flag,0); if( pWInfo==0 ){ sqlite3ExprListDelete(db, pDel); goto select_end; } updateAccumulator(pParse, &sAggInfo); assert( pMinMax==0 || pMinMax->nExpr==1 ); | | | | | 5157 5158 5159 5160 5161 5162 5163 5164 5165 5166 5167 5168 5169 5170 5171 5172 5173 5174 5175 5176 5177 5178 5179 5180 5181 5182 5183 5184 5185 5186 5187 5188 5189 5190 5191 5192 5193 5194 5195 5196 5197 5198 5199 | pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, pMinMax,0,flag,0); if( pWInfo==0 ){ sqlite3ExprListDelete(db, pDel); goto select_end; } updateAccumulator(pParse, &sAggInfo); assert( pMinMax==0 || pMinMax->nExpr==1 ); if( sqlite3WhereIsOrdered(pWInfo)>0 ){ sqlite3VdbeAddOp2(v, OP_Goto, 0, sqlite3WhereBreakLabel(pWInfo)); VdbeComment((v, "%s() by index", (flag==WHERE_ORDERBY_MIN?"min":"max"))); } sqlite3WhereEnd(pWInfo); finalizeAggFunctions(pParse, &sAggInfo); } pOrderBy = 0; sqlite3ExprIfFalse(pParse, pHaving, addrEnd, SQLITE_JUMPIFNULL); selectInnerLoop(pParse, p, p->pEList, -1, 0, 0, 0, pDest, addrEnd, addrEnd); sqlite3ExprListDelete(db, pDel); } sqlite3VdbeResolveLabel(v, addrEnd); } /* endif aggregate query */ if( sDistinct.eTnctType==WHERE_DISTINCT_UNORDERED ){ explainTempTable(pParse, "DISTINCT"); } /* If there is an ORDER BY clause, then we need to sort the results ** and send them to the callback one by one. */ if( pOrderBy ){ explainTempTable(pParse, "ORDER BY"); generateSortTail(pParse, p, pEList->nExpr, pDest); } /* Jump here to skip this query */ sqlite3VdbeResolveLabel(v, iEnd); /* The SELECT was successfully coded. Set the return code to 0 |
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Changes to src/where.c.
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35 36 37 38 39 40 41 | } /* ** Return TRUE if the WHERE clause returns rows in ORDER BY order. ** Return FALSE if the output needs to be sorted. */ int sqlite3WhereIsOrdered(WhereInfo *pWInfo){ | | | 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 | } /* ** Return TRUE if the WHERE clause returns rows in ORDER BY order. ** Return FALSE if the output needs to be sorted. */ int sqlite3WhereIsOrdered(WhereInfo *pWInfo){ return pWInfo->nOBSat; } /* ** Return the VDBE address or label to jump to in order to continue ** immediately with the next row of a WHERE clause. */ int sqlite3WhereContinueLabel(WhereInfo *pWInfo){ |
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3032 3033 3034 3035 3036 3037 3038 3039 | ** 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. */ if( (pWInfo->wctrlFlags&WHERE_ORDERBY_MIN)!=0 | > > > | | 3032 3033 3034 3035 3036 3037 3038 3039 3040 3041 3042 3043 3044 3045 3046 3047 3048 3049 3050 | ** 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->u.btree.nSkip==0 ); bSeekPastNull = 1; nExtraReg = 1; } |
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5195 5196 5197 5198 5199 5200 5201 | pWInfo->eDistinct = WHERE_DISTINCT_ORDERED; } } if( pWInfo->pOrderBy && pFrom->isOrdered==pWInfo->pOrderBy->nExpr ){ if( pWInfo->wctrlFlags & WHERE_DISTINCTBY ){ pWInfo->eDistinct = WHERE_DISTINCT_ORDERED; }else{ | | | 5198 5199 5200 5201 5202 5203 5204 5205 5206 5207 5208 5209 5210 5211 5212 | pWInfo->eDistinct = WHERE_DISTINCT_ORDERED; } } if( pWInfo->pOrderBy && pFrom->isOrdered==pWInfo->pOrderBy->nExpr ){ if( pWInfo->wctrlFlags & WHERE_DISTINCTBY ){ pWInfo->eDistinct = WHERE_DISTINCT_ORDERED; }else{ pWInfo->nOBSat = pFrom->isOrdered; pWInfo->revMask = pFrom->revLoop; } } pWInfo->nRowOut = pFrom->nRow; /* Free temporary memory and return success */ sqlite3DbFree(db, pSpace); |
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5280 5281 5282 5283 5284 5285 5286 | } if( pLoop->wsFlags ){ pLoop->nOut = (LogEst)1; pWInfo->a[0].pWLoop = pLoop; pLoop->maskSelf = getMask(&pWInfo->sMaskSet, iCur); pWInfo->a[0].iTabCur = iCur; pWInfo->nRowOut = 1; | | | 5283 5284 5285 5286 5287 5288 5289 5290 5291 5292 5293 5294 5295 5296 5297 | } if( pLoop->wsFlags ){ pLoop->nOut = (LogEst)1; pWInfo->a[0].pWLoop = pLoop; pLoop->maskSelf = getMask(&pWInfo->sMaskSet, iCur); pWInfo->a[0].iTabCur = iCur; pWInfo->nRowOut = 1; if( pWInfo->pOrderBy ) pWInfo->nOBSat = pWInfo->pOrderBy->nExpr; if( pWInfo->wctrlFlags & WHERE_WANT_DISTINCT ){ pWInfo->eDistinct = WHERE_DISTINCT_UNIQUE; } #ifdef SQLITE_DEBUG pLoop->cId = '0'; #endif return 1; |
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5488 5489 5490 5491 5492 5493 5494 | sWLB.pWC->a[ii].wtFlags |= TERM_CODED; } } /* Special case: No FROM clause */ if( nTabList==0 ){ | | | 5491 5492 5493 5494 5495 5496 5497 5498 5499 5500 5501 5502 5503 5504 5505 | sWLB.pWC->a[ii].wtFlags |= TERM_CODED; } } /* Special case: No FROM clause */ if( nTabList==0 ){ if( pOrderBy ) pWInfo->nOBSat = pOrderBy->nExpr; if( wctrlFlags & WHERE_WANT_DISTINCT ){ pWInfo->eDistinct = WHERE_DISTINCT_UNIQUE; } } /* Assign a bit from the bitmask to every term in the FROM clause. ** |
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5599 5600 5601 5602 5603 5604 5605 | if( pParse->nErr || NEVER(db->mallocFailed) ){ goto whereBeginError; } #ifdef WHERETRACE_ENABLED /* !=0 */ if( sqlite3WhereTrace ){ int ii; sqlite3DebugPrintf("---- Solution nRow=%d", pWInfo->nRowOut); | | | | 5602 5603 5604 5605 5606 5607 5608 5609 5610 5611 5612 5613 5614 5615 5616 5617 | if( pParse->nErr || NEVER(db->mallocFailed) ){ goto whereBeginError; } #ifdef WHERETRACE_ENABLED /* !=0 */ if( sqlite3WhereTrace ){ int ii; sqlite3DebugPrintf("---- Solution nRow=%d", pWInfo->nRowOut); if( pWInfo->nOBSat>0 ){ sqlite3DebugPrintf(" ORDERBY=%d,0x%llx", pWInfo->nOBSat, pWInfo->revMask); } switch( pWInfo->eDistinct ){ case WHERE_DISTINCT_UNIQUE: { sqlite3DebugPrintf(" DISTINCT=unique"); break; } case WHERE_DISTINCT_ORDERED: { |
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Changes to src/whereInt.h.
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393 394 395 396 397 398 399 | SrcList *pTabList; /* List of tables in the join */ ExprList *pOrderBy; /* The ORDER BY clause or NULL */ ExprList *pResultSet; /* Result set. DISTINCT operates on these */ WhereLoop *pLoops; /* List of all WhereLoop objects */ Bitmask revMask; /* Mask of ORDER BY terms that need reversing */ LogEst nRowOut; /* Estimated number of output rows */ u16 wctrlFlags; /* Flags originally passed to sqlite3WhereBegin() */ | | | 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 | SrcList *pTabList; /* List of tables in the join */ ExprList *pOrderBy; /* The ORDER BY clause or NULL */ ExprList *pResultSet; /* Result set. DISTINCT operates on these */ WhereLoop *pLoops; /* List of all WhereLoop objects */ Bitmask revMask; /* Mask of ORDER BY terms that need reversing */ LogEst nRowOut; /* Estimated number of output rows */ u16 wctrlFlags; /* Flags originally passed to sqlite3WhereBegin() */ i8 nOBSat; /* Number of ORDER BY terms satisfied by indices */ u8 okOnePass; /* Ok to use one-pass algorithm for UPDATE/DELETE */ u8 untestedTerms; /* Not all WHERE terms resolved by outer loop */ u8 eDistinct; /* One of the WHERE_DISTINCT_* values below */ u8 nLevel; /* Number of nested loop */ int iTop; /* The very beginning of the WHERE loop */ int iContinue; /* Jump here to continue with next record */ int iBreak; /* Jump here to break out of the loop */ |
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