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Overview
Comment: | 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. |
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Timelines: | family | ancestors | descendants | both | qp-enhancements |
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SHA1: |
1104d42e104d561ce60d05d158acfe49 |
User & Date: | drh 2012-09-25 14:29:39.134 |
Context
2012-09-25
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20:43 | Augment the WhereBestIdx structure to pass down into the query planner information that might be used to better detect ORDER BY and DISTINCT optimizations spanning multiple tables of a join. (check-in: 4226e51ff8 user: drh tags: qp-enhancements) | |
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) | |
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) | |
Changes
Changes to src/where.c.
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263 264 265 266 267 268 269 270 271 272 273 274 275 276 | #define WHERE_UNIQUE 0x04000000 /* Selects no more than one row */ #define WHERE_VIRTUALTABLE 0x08000000 /* Use virtual-table processing */ #define WHERE_MULTI_OR 0x10000000 /* OR using multiple indices */ #define WHERE_TEMP_INDEX 0x20000000 /* Uses an ephemeral index */ #define WHERE_DISTINCT 0x40000000 /* Correct order for DISTINCT */ #define WHERE_COVER_SCAN 0x80000000 /* Full scan of a covering index */ /* ** Initialize a preallocated WhereClause structure. */ static void whereClauseInit( WhereClause *pWC, /* The WhereClause to be initialized */ Parse *pParse, /* The parsing context */ WhereMaskSet *pMaskSet, /* Mapping from table cursor numbers to bitmasks */ | > > > > > > > > > > > > > > > > > > > > | 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 | #define WHERE_UNIQUE 0x04000000 /* Selects no more than one row */ #define WHERE_VIRTUALTABLE 0x08000000 /* Use virtual-table processing */ #define WHERE_MULTI_OR 0x10000000 /* OR using multiple indices */ #define WHERE_TEMP_INDEX 0x20000000 /* Uses an ephemeral index */ #define WHERE_DISTINCT 0x40000000 /* Correct order for DISTINCT */ #define WHERE_COVER_SCAN 0x80000000 /* Full scan of a covering index */ /* ** This module contains many separate subroutines that work together to ** find the best indices to use for accessing a particular table in a query. ** An instance of the following structure holds context information about the ** index search so that it can be more easily passed between the various ** routines. */ typedef struct WhereBestIdx WhereBestIdx; struct WhereBestIdx { Parse *pParse; /* Parser context */ WhereClause *pWC; /* The WHERE clause */ struct SrcList_item *pSrc; /* The FROM clause term to search */ Bitmask notReady; /* Mask of cursors not available */ Bitmask notValid; /* Cursors not available for any purpose */ ExprList *pOrderBy; /* The ORDER BY clause */ ExprList *pDistinct; /* The select-list if query is DISTINCT */ sqlite3_index_info **ppIdxInfo; /* Index information passed to xBestIndex */ WhereCost cost; /* Lowest cost query plan */ }; /* ** Initialize a preallocated WhereClause structure. */ static void whereClauseInit( WhereClause *pWC, /* The WhereClause to be initialized */ Parse *pParse, /* The parsing context */ WhereMaskSet *pMaskSet, /* Mapping from table cursor numbers to bitmasks */ |
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1807 1808 1809 1810 1811 1812 1813 | #define TRACE_IDX_INPUTS(A) #define TRACE_IDX_OUTPUTS(A) #endif /* ** Required because bestIndex() is called by bestOrClauseIndex() */ | | < < | < < < < < < < < > > | | | > > > > > < | | > | | | | | | | | | | | | | 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 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 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 | #define TRACE_IDX_INPUTS(A) #define TRACE_IDX_OUTPUTS(A) #endif /* ** Required because bestIndex() is called by bestOrClauseIndex() */ static void bestIndex(WhereBestIdx*); /* ** 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. */ static void bestOrClauseIndex(WhereBestIdx *p){ #ifndef SQLITE_OMIT_OR_OPTIMIZATION WhereClause *pWC = p->pWC; /* The WHERE clause */ struct SrcList_item *pSrc = p->pSrc; /* The FROM clause term to search */ const int iCur = pSrc->iCursor; /* The cursor of the table */ const Bitmask maskSrc = getMask(pWC->pMaskSet, iCur); /* Bitmask for pSrc */ WhereTerm * const pWCEnd = &pWC->a[pWC->nTerm]; /* End of pWC->a[] */ WhereTerm *pTerm; /* A single term of the WHERE clause */ /* The OR-clause optimization is disallowed if the INDEXED BY or ** NOT INDEXED clauses are used or if the WHERE_AND_ONLY bit is set. */ if( pSrc->notIndexed || pSrc->pIndex!=0 ){ return; } if( pWC->wctrlFlags & WHERE_AND_ONLY ){ return; } /* Search the WHERE clause terms for a usable WO_OR term. */ for(pTerm=pWC->a; pTerm<pWCEnd; pTerm++){ if( pTerm->eOperator==WO_OR && ((pTerm->prereqAll & ~maskSrc) & p->notReady)==0 && (pTerm->u.pOrInfo->indexable & maskSrc)!=0 ){ WhereClause * const pOrWC = &pTerm->u.pOrInfo->wc; WhereTerm * const pOrWCEnd = &pOrWC->a[pOrWC->nTerm]; WhereTerm *pOrTerm; int flags = WHERE_MULTI_OR; double rTotal = 0; double nRow = 0; Bitmask used = 0; WhereBestIdx sBOI; sBOI = *p; sBOI.pOrderBy = 0; sBOI.pDistinct = 0; sBOI.ppIdxInfo = 0; for(pOrTerm=pOrWC->a; pOrTerm<pOrWCEnd; pOrTerm++){ WHERETRACE(("... Multi-index OR testing for term %d of %d....\n", (pOrTerm - pOrWC->a), (pTerm - pWC->a) )); if( pOrTerm->eOperator==WO_AND ){ sBOI.pWC = &pOrTerm->u.pAndInfo->wc; bestIndex(&sBOI); }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; sBOI.pWC = &tempWC; bestIndex(&sBOI); }else{ continue; } rTotal += sBOI.cost.rCost; nRow += sBOI.cost.plan.nRow; used |= sBOI.cost.used; if( rTotal>=p->cost.rCost ) break; } /* If there is an ORDER BY clause, increase the scan cost to account ** for the cost of the sort. */ if( p->pOrderBy!=0 ){ WHERETRACE(("... sorting increases OR cost %.9g to %.9g\n", rTotal, rTotal+nRow*estLog(nRow))); rTotal += nRow*estLog(nRow); } /* If the cost of scanning using this OR term for optimization is ** less than the current cost stored in pCost, replace the contents ** of pCost. */ WHERETRACE(("... multi-index OR cost=%.9g nrow=%.9g\n", rTotal, nRow)); if( rTotal<p->cost.rCost ){ p->cost.rCost = rTotal; p->cost.used = used; p->cost.plan.nRow = nRow; p->cost.plan.wsFlags = flags; p->cost.plan.u.pTerm = pTerm; } } } #endif /* SQLITE_OMIT_OR_OPTIMIZATION */ } #ifndef SQLITE_OMIT_AUTOMATIC_INDEX |
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1937 1938 1939 1940 1941 1942 1943 | ** If the query plan for pSrc specified in pCost is a full table scan ** and indexing is allows (if there is no NOT INDEXED clause) and it ** possible to construct a transient index that would perform better ** than a full table scan even when the cost of constructing the index ** is taken into account, then alter the query plan to use the ** transient index. */ | | | | | < < < | | | | | | | | | | | | 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 | ** If the query plan for pSrc specified in pCost is a full table scan ** and indexing is allows (if there is no NOT INDEXED clause) and it ** possible to construct a transient index that would perform better ** than a full table scan even when the cost of constructing the index ** is taken into account, then alter the query plan to use the ** transient index. */ static void bestAutomaticIndex(WhereBestIdx *p){ Parse *pParse = p->pParse; /* The parsing context */ WhereClause *pWC = p->pWC; /* The WHERE clause */ struct SrcList_item *pSrc = p->pSrc; /* The FROM clause term to search */ double nTableRow; /* Rows in the input table */ double logN; /* log(nTableRow) */ double costTempIdx; /* per-query cost of the transient index */ WhereTerm *pTerm; /* A single term of the WHERE clause */ WhereTerm *pWCEnd; /* End of pWC->a[] */ Table *pTable; /* Table tht might be indexed */ if( pParse->nQueryLoop<=(double)1 ){ /* There is no point in building an automatic index for a single scan */ return; } if( (pParse->db->flags & SQLITE_AutoIndex)==0 ){ /* Automatic indices are disabled at run-time */ return; } if( (p->cost.plan.wsFlags & WHERE_NOT_FULLSCAN)!=0 ){ /* We already have some kind of index in use for this query. */ return; } if( pSrc->notIndexed ){ /* The NOT INDEXED clause appears in the SQL. */ return; } if( pSrc->isCorrelated ){ /* The source is a correlated sub-query. No point in indexing it. */ return; } assert( pParse->nQueryLoop >= (double)1 ); pTable = pSrc->pTab; nTableRow = pTable->nRowEst; logN = estLog(nTableRow); costTempIdx = 2*logN*(nTableRow/pParse->nQueryLoop + 1); if( costTempIdx>=p->cost.rCost ){ /* The cost of creating the transient table would be greater than ** doing the full table scan */ return; } /* Search for any equality comparison term */ pWCEnd = &pWC->a[pWC->nTerm]; for(pTerm=pWC->a; pTerm<pWCEnd; pTerm++){ if( termCanDriveIndex(pTerm, pSrc, p->notReady) ){ WHERETRACE(("auto-index reduces cost from %.1f to %.1f\n", p->cost.rCost, costTempIdx)); p->cost.rCost = costTempIdx; p->cost.plan.nRow = logN + 1; p->cost.plan.wsFlags = WHERE_TEMP_INDEX; p->cost.used = pTerm->prereqRight; break; } } } #else # define bestAutomaticIndex(A) /* no-op */ #endif /* SQLITE_OMIT_AUTOMATIC_INDEX */ #ifndef SQLITE_OMIT_AUTOMATIC_INDEX /* ** Generate code to construct the Index object for an automatic index ** and to set up the WhereLevel object pLevel so that the code generator |
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2159 2160 2161 2162 2163 2164 2165 | #ifndef SQLITE_OMIT_VIRTUALTABLE /* ** Allocate and populate an sqlite3_index_info structure. It is the ** responsibility of the caller to eventually release the structure ** by passing the pointer returned by this function to sqlite3_free(). */ | | | | | | < | 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 | #ifndef SQLITE_OMIT_VIRTUALTABLE /* ** Allocate and populate an sqlite3_index_info structure. It is the ** responsibility of the caller to eventually release the structure ** by passing the pointer returned by this function to sqlite3_free(). */ static sqlite3_index_info *allocateIndexInfo(WhereBestIdx *p){ Parse *pParse = p->pParse; WhereClause *pWC = p->pWC; struct SrcList_item *pSrc = p->pSrc; ExprList *pOrderBy = p->pOrderBy; int i, j; int nTerm; struct sqlite3_index_constraint *pIdxCons; struct sqlite3_index_orderby *pIdxOrderBy; struct sqlite3_index_constraint_usage *pUsage; WhereTerm *pTerm; int nOrderBy; |
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2194 2195 2196 2197 2198 2199 2200 | /* If the ORDER BY clause contains only columns in the current ** virtual table then allocate space for the aOrderBy part of ** the sqlite3_index_info structure. */ nOrderBy = 0; if( pOrderBy ){ | > | | | | 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 | /* If the ORDER BY clause contains only columns in the current ** virtual table then allocate space for the aOrderBy part of ** the sqlite3_index_info structure. */ nOrderBy = 0; if( pOrderBy ){ int n = pOrderBy->nExpr; for(i=0; i<n; i++){ Expr *pExpr = pOrderBy->a[i].pExpr; if( pExpr->op!=TK_COLUMN || pExpr->iTable!=pSrc->iCursor ) break; } if( i==n){ nOrderBy = n; } } /* Allocate the sqlite3_index_info structure */ pIdxInfo = sqlite3DbMallocZero(pParse->db, sizeof(*pIdxInfo) + (sizeof(*pIdxCons) + sizeof(*pUsage))*nTerm |
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2323 2324 2325 2326 2327 2328 2329 | ** same virtual table. The sqlite3_index_info structure is created ** and initialized on the first invocation and reused on all subsequent ** invocations. The sqlite3_index_info structure is also used when ** code is generated to access the virtual table. The whereInfoDelete() ** routine takes care of freeing the sqlite3_index_info structure after ** everybody has finished with it. */ | | | | | < < < < < < | | | | | 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372 2373 2374 2375 2376 | ** same virtual table. The sqlite3_index_info structure is created ** and initialized on the first invocation and reused on all subsequent ** invocations. The sqlite3_index_info structure is also used when ** code is generated to access the virtual table. The whereInfoDelete() ** routine takes care of freeing the sqlite3_index_info structure after ** everybody has finished with it. */ static void bestVirtualIndex(WhereBestIdx *p){ Parse *pParse = p->pParse; /* The parsing context */ WhereClause *pWC = p->pWC; /* The WHERE clause */ struct SrcList_item *pSrc = p->pSrc; /* The FROM clause term to search */ Table *pTab = pSrc->pTab; sqlite3_index_info *pIdxInfo; struct sqlite3_index_constraint *pIdxCons; struct sqlite3_index_constraint_usage *pUsage; WhereTerm *pTerm; int i, j; int nOrderBy; double rCost; /* Make sure wsFlags is initialized to some sane value. Otherwise, if the ** malloc in allocateIndexInfo() fails and this function returns leaving ** wsFlags in an uninitialized state, the caller may behave unpredictably. */ memset(&p->cost, 0, sizeof(p->cost)); p->cost.plan.wsFlags = WHERE_VIRTUALTABLE; /* If the sqlite3_index_info structure has not been previously ** allocated and initialized, then allocate and initialize it now. */ pIdxInfo = *p->ppIdxInfo; if( pIdxInfo==0 ){ *p->ppIdxInfo = pIdxInfo = allocateIndexInfo(p); } if( pIdxInfo==0 ){ return; } /* At this point, the sqlite3_index_info structure that pIdxInfo points ** to will have been initialized, either during the current invocation or |
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2399 2400 2401 2402 2403 2404 2405 | ** each time. */ pIdxCons = *(struct sqlite3_index_constraint**)&pIdxInfo->aConstraint; pUsage = pIdxInfo->aConstraintUsage; for(i=0; i<pIdxInfo->nConstraint; i++, pIdxCons++){ j = pIdxCons->iTermOffset; pTerm = &pWC->a[j]; | | | | | | | | | | | | 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467 2468 2469 2470 2471 2472 2473 2474 2475 2476 2477 2478 2479 2480 | ** each time. */ pIdxCons = *(struct sqlite3_index_constraint**)&pIdxInfo->aConstraint; pUsage = pIdxInfo->aConstraintUsage; for(i=0; i<pIdxInfo->nConstraint; i++, pIdxCons++){ j = pIdxCons->iTermOffset; pTerm = &pWC->a[j]; pIdxCons->usable = (pTerm->prereqRight&p->notReady) ? 0 : 1; } memset(pUsage, 0, sizeof(pUsage[0])*pIdxInfo->nConstraint); if( pIdxInfo->needToFreeIdxStr ){ sqlite3_free(pIdxInfo->idxStr); } pIdxInfo->idxStr = 0; pIdxInfo->idxNum = 0; pIdxInfo->needToFreeIdxStr = 0; pIdxInfo->orderByConsumed = 0; /* ((double)2) In case of SQLITE_OMIT_FLOATING_POINT... */ pIdxInfo->estimatedCost = SQLITE_BIG_DBL / ((double)2); nOrderBy = pIdxInfo->nOrderBy; if( !p->pOrderBy ){ pIdxInfo->nOrderBy = 0; } if( vtabBestIndex(pParse, pTab, pIdxInfo) ){ return; } pIdxCons = *(struct sqlite3_index_constraint**)&pIdxInfo->aConstraint; for(i=0; i<pIdxInfo->nConstraint; i++){ if( pUsage[i].argvIndex>0 ){ p->cost.used |= pWC->a[pIdxCons[i].iTermOffset].prereqRight; } } /* If there is an ORDER BY clause, and the selected virtual table index ** does not satisfy it, increase the cost of the scan accordingly. This ** matches the processing for non-virtual tables in bestBtreeIndex(). */ rCost = pIdxInfo->estimatedCost; if( p->pOrderBy && pIdxInfo->orderByConsumed==0 ){ rCost += estLog(rCost)*rCost; } /* The cost is not allowed to be larger than SQLITE_BIG_DBL (the ** inital value of lowestCost in this loop. If it is, then the ** (cost<lowestCost) test below will never be true. ** ** Use "(double)2" instead of "2.0" in case OMIT_FLOATING_POINT ** is defined. */ if( (SQLITE_BIG_DBL/((double)2))<rCost ){ p->cost.rCost = (SQLITE_BIG_DBL/((double)2)); }else{ p->cost.rCost = rCost; } p->cost.plan.u.pVtabIdx = pIdxInfo; if( pIdxInfo->orderByConsumed ){ p->cost.plan.wsFlags |= WHERE_ORDERBY; } p->cost.plan.nEq = 0; pIdxInfo->nOrderBy = nOrderBy; /* Try to find a more efficient access pattern by using multiple indexes ** to optimize an OR expression within the WHERE clause. */ bestOrClauseIndex(p); } #endif /* SQLITE_OMIT_VIRTUALTABLE */ #ifdef SQLITE_ENABLE_STAT3 /* ** Estimate the location of a particular key among all keys in an ** index. Store the results in aStat as follows: |
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2860 2861 2862 2863 2864 2865 2866 | return rc; } #endif /* defined(SQLITE_ENABLE_STAT3) */ /* ** Find the best query plan for accessing a particular table. Write the | | < | 2868 2869 2870 2871 2872 2873 2874 2875 2876 2877 2878 2879 2880 2881 2882 | return rc; } #endif /* defined(SQLITE_ENABLE_STAT3) */ /* ** Find the best query plan for accessing a particular table. Write the ** best query plan and its cost into the p->cost. ** ** The lowest cost plan wins. The cost is an estimate of the amount of ** CPU and disk I/O needed to process the requested result. ** Factors that influence cost include: ** ** * The estimated number of rows that will be retrieved. (The ** fewer the better.) |
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2886 2887 2888 2889 2890 2891 2892 | ** then the cost is calculated in the usual way. ** ** If a NOT INDEXED clause (pSrc->notIndexed!=0) was attached to the table ** in the SELECT statement, then no indexes are considered. However, the ** selected plan may still take advantage of the built-in rowid primary key ** index. */ | | | | | < < < < < < | | | | 2893 2894 2895 2896 2897 2898 2899 2900 2901 2902 2903 2904 2905 2906 2907 2908 2909 2910 2911 2912 2913 2914 2915 2916 2917 2918 2919 2920 2921 2922 2923 | ** then the cost is calculated in the usual way. ** ** If a NOT INDEXED clause (pSrc->notIndexed!=0) was attached to the table ** in the SELECT statement, then no indexes are considered. However, the ** selected plan may still take advantage of the built-in rowid primary key ** index. */ static void bestBtreeIndex(WhereBestIdx *p){ Parse *pParse = p->pParse; /* The parsing context */ WhereClause *pWC = p->pWC; /* The WHERE clause */ struct SrcList_item *pSrc = p->pSrc; /* The FROM clause term to search */ int iCur = pSrc->iCursor; /* The cursor of the table to be accessed */ Index *pProbe; /* An index we are evaluating */ Index *pIdx; /* Copy of pProbe, or zero for IPK index */ int eqTermMask; /* Current mask of valid equality operators */ int idxEqTermMask; /* Index mask of valid equality operators */ Index sPk; /* A fake index object for the primary key */ tRowcnt aiRowEstPk[2]; /* The aiRowEst[] value for the sPk index */ int aiColumnPk = -1; /* The aColumn[] value for the sPk index */ int wsFlagMask; /* Allowed flags in p->cost.plan.wsFlag */ /* Initialize the cost to a worst-case value */ memset(&p->cost, 0, sizeof(p->cost)); p->cost.rCost = SQLITE_BIG_DBL; /* If the pSrc table is the right table of a LEFT JOIN then we may not ** use an index to satisfy IS NULL constraints on that table. This is ** because columns might end up being NULL if the table does not match - ** a circumstance which the index cannot help us discover. Ticket #2177. */ if( pSrc->jointype & JT_LEFT ){ |
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3032 3033 3034 3035 3036 3037 3038 | ** SELECT a, b, c FROM tbl WHERE a = 1; */ int nEq; /* Number of == or IN terms matching index */ int bInEst = 0; /* True if "x IN (SELECT...)" seen */ int nInMul = 1; /* Number of distinct equalities to lookup */ double rangeDiv = (double)1; /* Estimated reduction in search space */ int nBound = 0; /* Number of range constraints seen */ | | | | | 3033 3034 3035 3036 3037 3038 3039 3040 3041 3042 3043 3044 3045 3046 3047 3048 3049 3050 3051 3052 3053 3054 3055 3056 3057 3058 | ** SELECT a, b, c FROM tbl WHERE a = 1; */ int nEq; /* Number of == or IN terms matching index */ int bInEst = 0; /* True if "x IN (SELECT...)" seen */ int nInMul = 1; /* Number of distinct equalities to lookup */ double rangeDiv = (double)1; /* Estimated reduction in search space */ int nBound = 0; /* Number of range constraints seen */ int bSort = !!p->pOrderBy; /* True if external sort required */ int bDist = !!p->pDistinct; /* True if index cannot help with DISTINCT */ int bLookup = 0; /* True if not a covering index */ WhereTerm *pTerm; /* A single term of the WHERE clause */ #ifdef SQLITE_ENABLE_STAT3 WhereTerm *pFirstTerm = 0; /* First term matching the index */ #endif /* Determine the values of nEq and nInMul */ for(nEq=0; nEq<pProbe->nColumn; nEq++){ int j = pProbe->aiColumn[nEq]; pTerm = findTerm(pWC, iCur, j, p->notReady, eqTermMask, pIdx); if( pTerm==0 ) break; wsFlags |= (WHERE_COLUMN_EQ|WHERE_ROWID_EQ); testcase( pTerm->pWC!=pWC ); if( pTerm->eOperator & WO_IN ){ Expr *pExpr = pTerm->pExpr; wsFlags |= WHERE_COLUMN_IN; if( ExprHasProperty(pExpr, EP_xIsSelect) ){ |
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3084 3085 3086 3087 3088 3089 3090 | testcase( wsFlags & WHERE_COLUMN_IN ); testcase( wsFlags & WHERE_COLUMN_NULL ); if( (wsFlags & (WHERE_COLUMN_IN|WHERE_COLUMN_NULL))==0 ){ wsFlags |= WHERE_UNIQUE; } }else if( pProbe->bUnordered==0 ){ int j = (nEq==pProbe->nColumn ? -1 : pProbe->aiColumn[nEq]); | | | > | | 3085 3086 3087 3088 3089 3090 3091 3092 3093 3094 3095 3096 3097 3098 3099 3100 3101 3102 | testcase( wsFlags & WHERE_COLUMN_IN ); testcase( wsFlags & WHERE_COLUMN_NULL ); if( (wsFlags & (WHERE_COLUMN_IN|WHERE_COLUMN_NULL))==0 ){ wsFlags |= WHERE_UNIQUE; } }else if( pProbe->bUnordered==0 ){ int j = (nEq==pProbe->nColumn ? -1 : pProbe->aiColumn[nEq]); if( findTerm(pWC, iCur, j, p->notReady, WO_LT|WO_LE|WO_GT|WO_GE, pIdx) ){ WhereTerm *pTop, *pBtm; pTop = findTerm(pWC, iCur, j, p->notReady, WO_LT|WO_LE, pIdx); pBtm = findTerm(pWC, iCur, j, p->notReady, WO_GT|WO_GE, pIdx); whereRangeScanEst(pParse, pProbe, nEq, pBtm, pTop, &rangeDiv); if( pTop ){ nBound = 1; wsFlags |= WHERE_TOP_LIMIT; used |= pTop->prereqRight; testcase( pTop->pWC!=pWC ); } |
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3109 3110 3111 3112 3113 3114 3115 | } /* If there is an ORDER BY clause and the index being considered will ** naturally scan rows in the required order, set the appropriate flags ** in wsFlags. Otherwise, if there is an ORDER BY clause but the index ** will scan rows in a different order, set the bSort variable. */ if( isSortingIndex( | | | | 3111 3112 3113 3114 3115 3116 3117 3118 3119 3120 3121 3122 3123 3124 3125 3126 3127 3128 3129 3130 3131 3132 3133 3134 3135 | } /* If there is an ORDER BY clause and the index being considered will ** naturally scan rows in the required order, set the appropriate flags ** in wsFlags. Otherwise, if there is an ORDER BY clause but the index ** will scan rows in a different order, set the bSort variable. */ if( isSortingIndex( pParse, pWC->pMaskSet, pProbe, iCur, p->pOrderBy, nEq, wsFlags, &rev) ){ bSort = 0; wsFlags |= WHERE_ROWID_RANGE|WHERE_COLUMN_RANGE|WHERE_ORDERBY; wsFlags |= (rev ? WHERE_REVERSE : 0); } /* If there is a DISTINCT qualifier and this index will scan rows in ** order of the DISTINCT expressions, clear bDist and set the appropriate ** flags in wsFlags. */ if( isDistinctIndex(pParse, pWC, pProbe, iCur, p->pDistinct, nEq) && (wsFlags & WHERE_COLUMN_IN)==0 ){ bDist = 0; wsFlags |= WHERE_ROWID_RANGE|WHERE_COLUMN_RANGE|WHERE_DISTINCT; } /* If currently calculating the cost of using an index (not the IPK |
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3279 3280 3281 3282 3283 3284 3285 | ** mask will only have one bit set - the bit for the current table. ** The notValid mask, on the other hand, always has all bits set for ** tables that are not in outer loops. If notReady is used here instead ** of notValid, then a optimal index that depends on inner joins loops ** might be selected even when there exists an optimal index that has ** no such dependency. */ | | | | 3281 3282 3283 3284 3285 3286 3287 3288 3289 3290 3291 3292 3293 3294 3295 3296 3297 3298 3299 3300 3301 3302 3303 3304 | ** mask will only have one bit set - the bit for the current table. ** The notValid mask, on the other hand, always has all bits set for ** tables that are not in outer loops. If notReady is used here instead ** of notValid, then a optimal index that depends on inner joins loops ** might be selected even when there exists an optimal index that has ** no such dependency. */ if( nRow>2 && cost<=p->cost.rCost ){ int k; /* Loop counter */ int nSkipEq = nEq; /* Number of == constraints to skip */ int nSkipRange = nBound; /* Number of < constraints to skip */ Bitmask thisTab; /* Bitmap for pSrc */ thisTab = getMask(pWC->pMaskSet, iCur); for(pTerm=pWC->a, k=pWC->nTerm; nRow>2 && k; k--, pTerm++){ if( pTerm->wtFlags & TERM_VIRTUAL ) continue; if( (pTerm->prereqAll & p->notValid)!=thisTab ) continue; if( pTerm->eOperator & (WO_EQ|WO_IN|WO_ISNULL) ){ if( nSkipEq ){ /* Ignore the first nEq equality matches since the index ** has already accounted for these */ nSkipEq--; }else{ /* Assume each additional equality match reduces the result |
︙ | ︙ | |||
3327 3328 3329 3330 3331 3332 3333 | WHERETRACE(( "%s(%s): nEq=%d nInMul=%d rangeDiv=%d bSort=%d bLookup=%d wsFlags=0x%x\n" " notReady=0x%llx log10N=%.1f nRow=%.1f cost=%.1f used=0x%llx\n", pSrc->pTab->zName, (pIdx ? pIdx->zName : "ipk"), nEq, nInMul, (int)rangeDiv, bSort, bLookup, wsFlags, | | | | | | | | | | | | | | | | | | | | | < < < < < < < | | > | | | | | | 3329 3330 3331 3332 3333 3334 3335 3336 3337 3338 3339 3340 3341 3342 3343 3344 3345 3346 3347 3348 3349 3350 3351 3352 3353 3354 3355 3356 3357 3358 3359 3360 3361 3362 3363 3364 3365 3366 3367 3368 3369 3370 3371 3372 3373 3374 3375 3376 3377 3378 3379 3380 3381 3382 3383 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 | WHERETRACE(( "%s(%s): nEq=%d nInMul=%d rangeDiv=%d bSort=%d bLookup=%d wsFlags=0x%x\n" " notReady=0x%llx log10N=%.1f nRow=%.1f cost=%.1f used=0x%llx\n", pSrc->pTab->zName, (pIdx ? pIdx->zName : "ipk"), nEq, nInMul, (int)rangeDiv, bSort, bLookup, wsFlags, p->notReady, log10N, nRow, cost, used )); /* If this index is the best we have seen so far, then record this ** index and its cost in the pCost structure. */ if( (!pIdx || wsFlags) && (cost<p->cost.rCost || (cost<=p->cost.rCost && nRow<p->cost.plan.nRow)) ){ p->cost.rCost = cost; p->cost.used = used; p->cost.plan.nRow = nRow; p->cost.plan.wsFlags = (wsFlags&wsFlagMask); p->cost.plan.nEq = nEq; p->cost.plan.u.pIdx = pIdx; } /* If there was an INDEXED BY clause, then only that one index is ** considered. */ if( pSrc->pIndex ) break; /* Reset masks for the next index in the loop */ wsFlagMask = ~(WHERE_ROWID_EQ|WHERE_ROWID_RANGE); eqTermMask = idxEqTermMask; } /* If there is no ORDER BY clause and the SQLITE_ReverseOrder flag ** is set, then reverse the order that the index will be scanned ** in. This is used for application testing, to help find cases ** where application behaviour depends on the (undefined) order that ** SQLite outputs rows in in the absence of an ORDER BY clause. */ if( !p->pOrderBy && pParse->db->flags & SQLITE_ReverseOrder ){ p->cost.plan.wsFlags |= WHERE_REVERSE; } assert( p->pOrderBy || (p->cost.plan.wsFlags&WHERE_ORDERBY)==0 ); assert( p->cost.plan.u.pIdx==0 || (p->cost.plan.wsFlags&WHERE_ROWID_EQ)==0 ); assert( pSrc->pIndex==0 || p->cost.plan.u.pIdx==0 || p->cost.plan.u.pIdx==pSrc->pIndex ); WHERETRACE(("best index is: %s\n", ((p->cost.plan.wsFlags & WHERE_NOT_FULLSCAN)==0 ? "none" : p->cost.plan.u.pIdx ? p->cost.plan.u.pIdx->zName : "ipk") )); bestOrClauseIndex(p); bestAutomaticIndex(p); p->cost.plan.wsFlags |= eqTermMask; } /* ** 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(WhereBestIdx *p){ #ifndef SQLITE_OMIT_VIRTUALTABLE if( IsVirtual(p->pSrc->pTab) ){ sqlite3_index_info *pIdxInfo = 0; p->ppIdxInfo = &pIdxInfo; bestVirtualIndex(p); if( pIdxInfo->needToFreeIdxStr ){ sqlite3_free(pIdxInfo->idxStr); } sqlite3DbFree(p->pParse->db, pIdxInfo); }else #endif { bestBtreeIndex(p); } } /* ** 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. |
︙ | ︙ | |||
4696 4697 4698 4699 4700 4701 4702 4703 | ){ int i; /* Loop counter */ int nByteWInfo; /* Num. bytes allocated for WhereInfo struct */ 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 */ | > < < | | > > > > > | 4692 4693 4694 4695 4696 4697 4698 4699 4700 4701 4702 4703 4704 4705 4706 4707 4708 4709 4710 4711 4712 4713 4714 4715 4716 4717 | ){ int i; /* Loop counter */ int nByteWInfo; /* Num. bytes allocated for WhereInfo struct */ 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 */ WhereBestIdx sWBI; /* Best index search context */ WhereMaskSet *pMaskSet; /* The expression mask set */ 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 */ /* Variable initialization */ memset(&sWBI, 0, sizeof(sWBI)); sWBI.pParse = pParse; /* The number of tables in the FROM clause is limited by the number of ** bits in a Bitmask */ testcase( pTabList->nSrc==BMS ); if( pTabList->nSrc>BMS ){ sqlite3ErrorMsg(pParse, "at most %d tables in a join", BMS); return 0; |
︙ | ︙ | |||
4743 4744 4745 4746 4747 4748 4749 | pWInfo = 0; goto whereBeginError; } pWInfo->nLevel = nTabList; pWInfo->pParse = pParse; pWInfo->pTabList = pTabList; pWInfo->iBreak = sqlite3VdbeMakeLabel(v); | | | | | | 4743 4744 4745 4746 4747 4748 4749 4750 4751 4752 4753 4754 4755 4756 4757 4758 4759 4760 4761 4762 4763 4764 4765 4766 4767 4768 4769 4770 4771 4772 | pWInfo = 0; goto whereBeginError; } pWInfo->nLevel = nTabList; pWInfo->pParse = pParse; pWInfo->pTabList = pTabList; pWInfo->iBreak = sqlite3VdbeMakeLabel(v); pWInfo->pWC = sWBI.pWC = (WhereClause *)&((u8 *)pWInfo)[nByteWInfo]; pWInfo->wctrlFlags = wctrlFlags; pWInfo->savedNQueryLoop = pParse->nQueryLoop; pMaskSet = (WhereMaskSet*)&sWBI.pWC[1]; /* Disable the DISTINCT optimization if SQLITE_DistinctOpt is set via ** sqlite3_test_ctrl(SQLITE_TESTCTRL_OPTIMIZATIONS,...) */ if( db->flags & SQLITE_DistinctOpt ) pDistinct = 0; /* Split the WHERE clause into separate subexpressions where each ** subexpression is separated by an AND operator. */ initMaskSet(pMaskSet); whereClauseInit(sWBI.pWC, pParse, pMaskSet, wctrlFlags); sqlite3ExprCodeConstants(pParse, pWhere); whereSplit(sWBI.pWC, pWhere, TK_AND); /* IMP: R-15842-53296 */ /* Special case: a WHERE clause that is constant. Evaluate the ** expression and either jump over all of the code or fall thru. */ if( pWhere && (nTabList==0 || sqlite3ExprIsConstantNotJoin(pWhere)) ){ sqlite3ExprIfFalse(pParse, pWhere, pWInfo->iBreak, SQLITE_JUMPIFNULL); pWhere = 0; |
︙ | ︙ | |||
4789 4790 4791 4792 4793 4794 4795 | ** with virtual tables. ** ** Note that bitmasks are created for all pTabList->nSrc tables in ** pTabList, not just the first nTabList tables. nTabList is normally ** equal to pTabList->nSrc but might be shortened to 1 if the ** WHERE_ONETABLE_ONLY flag is set. */ | | | | | | 4789 4790 4791 4792 4793 4794 4795 4796 4797 4798 4799 4800 4801 4802 4803 4804 4805 4806 4807 4808 4809 4810 4811 4812 4813 4814 4815 4816 4817 4818 4819 4820 4821 4822 4823 4824 4825 4826 4827 4828 4829 4830 4831 4832 4833 4834 4835 4836 4837 | ** with virtual tables. ** ** Note that bitmasks are created for all pTabList->nSrc tables in ** pTabList, not just the first nTabList tables. nTabList is normally ** equal to pTabList->nSrc but might be shortened to 1 if the ** WHERE_ONETABLE_ONLY flag is set. */ assert( sWBI.pWC->vmask==0 && pMaskSet->n==0 ); for(i=0; i<pTabList->nSrc; i++){ createMask(pMaskSet, pTabList->a[i].iCursor); #ifndef SQLITE_OMIT_VIRTUALTABLE if( ALWAYS(pTabList->a[i].pTab) && IsVirtual(pTabList->a[i].pTab) ){ sWBI.pWC->vmask |= ((Bitmask)1 << i); } #endif } #ifndef NDEBUG { Bitmask toTheLeft = 0; for(i=0; i<pTabList->nSrc; i++){ Bitmask m = getMask(pMaskSet, pTabList->a[i].iCursor); assert( (m-1)==toTheLeft ); toTheLeft |= m; } } #endif /* Analyze all of the subexpressions. Note that exprAnalyze() might ** add new virtual terms onto the end of the WHERE clause. We do not ** want to analyze these virtual terms, so start analyzing at the end ** and work forward so that the added virtual terms are never processed. */ exprAnalyzeAll(pTabList, sWBI.pWC); if( db->mallocFailed ){ goto whereBeginError; } /* Check if the DISTINCT qualifier, if there is one, is redundant. ** If it is, then set pDistinct to NULL and WhereInfo.eDistinct to ** WHERE_DISTINCT_UNIQUE to tell the caller to ignore the DISTINCT. */ if( pDistinct && isDistinctRedundant(pParse, pTabList, sWBI.pWC, pDistinct) ){ pDistinct = 0; pWInfo->eDistinct = WHERE_DISTINCT_UNIQUE; } /* Chose the best index to use for each table in the FROM clause. ** ** This loop fills in the following fields: |
︙ | ︙ | |||
4906 4907 4908 4909 4910 4911 4912 | ** as the cost of a linear scan through table t1, a simple greedy ** algorithm may choose to use t2 for the outer loop, which is a much ** costlier approach. */ nUnconstrained = 0; notIndexed = 0; for(isOptimal=(iFrom<nTabList-1); isOptimal>=0 && bestJ<0; isOptimal--){ | < | < < < | | > | | | | | | | | < | < | | | | | | 4906 4907 4908 4909 4910 4911 4912 4913 4914 4915 4916 4917 4918 4919 4920 4921 4922 4923 4924 4925 4926 4927 4928 4929 4930 4931 4932 4933 4934 4935 4936 4937 4938 4939 4940 4941 4942 4943 4944 4945 4946 4947 4948 4949 4950 4951 4952 4953 4954 4955 4956 | ** as the cost of a linear scan through table t1, a simple greedy ** algorithm may choose to use t2 for the outer loop, which is a much ** costlier approach. */ nUnconstrained = 0; notIndexed = 0; for(isOptimal=(iFrom<nTabList-1); isOptimal>=0 && bestJ<0; isOptimal--){ for(j=iFrom, sWBI.pSrc=&pTabList->a[j]; j<nTabList; j++, sWBI.pSrc++){ int doNotReorder; /* True if this table should not be reordered */ doNotReorder = (sWBI.pSrc->jointype & (JT_LEFT|JT_CROSS))!=0; if( j!=iFrom && doNotReorder ) break; m = getMask(pMaskSet, sWBI.pSrc->iCursor); if( (m & notReady)==0 ){ if( j==iFrom ) iFrom++; continue; } sWBI.notValid = notReady; sWBI.notReady = (isOptimal ? m : notReady); sWBI.pOrderBy = (i==0) ? pOrderBy : 0; sWBI.pDistinct = (i==0 ? pDistinct : 0); if( sWBI.pSrc->pIndex==0 ) nUnconstrained++; WHERETRACE(("=== trying table %d with isOptimal=%d ===\n", j, isOptimal)); assert( sWBI.pSrc->pTab ); #ifndef SQLITE_OMIT_VIRTUALTABLE if( IsVirtual(sWBI.pSrc->pTab) ){ sWBI.ppIdxInfo = &pWInfo->a[j].pIdxInfo; bestVirtualIndex(&sWBI); }else #endif { bestBtreeIndex(&sWBI); } assert( isOptimal || (sWBI.cost.used¬Ready)==0 ); /* If an INDEXED BY clause is present, then the plan must use that ** index if it uses any index at all */ assert( sWBI.pSrc->pIndex==0 || (sWBI.cost.plan.wsFlags & WHERE_NOT_FULLSCAN)==0 || sWBI.cost.plan.u.pIdx==sWBI.pSrc->pIndex ); if( isOptimal && (sWBI.cost.plan.wsFlags & WHERE_NOT_FULLSCAN)==0 ){ notIndexed |= m; } /* Conditions under which this table becomes the best so far: ** ** (1) The table must not depend on other tables that have not ** yet run. |
︙ | ︙ | |||
4971 4972 4973 4974 4975 4976 4977 | ** will be detected and relayed back to the application later. ** The NEVER() comes about because rule (2) above prevents ** An indexable full-table-scan from reaching rule (3). ** ** (4) The plan cost must be lower than prior plans or else the ** cost must be the same and the number of rows must be lower. */ | | | | | | | | | | | | 4966 4967 4968 4969 4970 4971 4972 4973 4974 4975 4976 4977 4978 4979 4980 4981 4982 4983 4984 4985 4986 4987 4988 4989 4990 4991 4992 4993 | ** will be detected and relayed back to the application later. ** The NEVER() comes about because rule (2) above prevents ** An indexable full-table-scan from reaching rule (3). ** ** (4) The plan cost must be lower than prior plans or else the ** cost must be the same and the number of rows must be lower. */ if( (sWBI.cost.used¬Ready)==0 /* (1) */ && (bestJ<0 || (notIndexed&m)!=0 /* (2) */ || (bestPlan.plan.wsFlags & WHERE_NOT_FULLSCAN)==0 || (sWBI.cost.plan.wsFlags & WHERE_NOT_FULLSCAN)!=0) && (nUnconstrained==0 || sWBI.pSrc->pIndex==0 /* (3) */ || NEVER((sWBI.cost.plan.wsFlags & WHERE_NOT_FULLSCAN)!=0)) && (bestJ<0 || sWBI.cost.rCost<bestPlan.rCost /* (4) */ || (sWBI.cost.rCost<=bestPlan.rCost && sWBI.cost.plan.nRow<bestPlan.plan.nRow)) ){ WHERETRACE(("=== table %d is best so far" " with cost=%g and nRow=%g\n", j, sWBI.cost.rCost, sWBI.cost.plan.nRow)); bestPlan = sWBI.cost; bestJ = j; } if( doNotReorder ) break; } } assert( bestJ>=0 ); assert( notReady & getMask(pMaskSet, pTabList->a[bestJ].iCursor) ); |
︙ | ︙ | |||
5073 5074 5075 5076 5077 5078 5079 5080 5081 5082 5083 5084 5085 5086 | */ sqlite3CodeVerifySchema(pParse, -1); /* Insert the cookie verifier Goto */ notReady = ~(Bitmask)0; pWInfo->nRowOut = (double)1; for(i=0, pLevel=pWInfo->a; i<nTabList; i++, pLevel++){ Table *pTab; /* Table to open */ int iDb; /* Index of database containing table/index */ pTabItem = &pTabList->a[pLevel->iFrom]; pTab = pTabItem->pTab; pLevel->iTabCur = pTabItem->iCursor; pWInfo->nRowOut *= pLevel->plan.nRow; iDb = sqlite3SchemaToIndex(db, pTab->pSchema); if( (pTab->tabFlags & TF_Ephemeral)!=0 || pTab->pSelect ){ | > | 5068 5069 5070 5071 5072 5073 5074 5075 5076 5077 5078 5079 5080 5081 5082 | */ sqlite3CodeVerifySchema(pParse, -1); /* Insert the cookie verifier Goto */ notReady = ~(Bitmask)0; pWInfo->nRowOut = (double)1; for(i=0, pLevel=pWInfo->a; i<nTabList; i++, pLevel++){ Table *pTab; /* Table to open */ int iDb; /* Index of database containing table/index */ struct SrcList_item *pTabItem; pTabItem = &pTabList->a[pLevel->iFrom]; pTab = pTabItem->pTab; pLevel->iTabCur = pTabItem->iCursor; pWInfo->nRowOut *= pLevel->plan.nRow; iDb = sqlite3SchemaToIndex(db, pTab->pSchema); if( (pTab->tabFlags & TF_Ephemeral)!=0 || pTab->pSelect ){ |
︙ | ︙ | |||
5108 5109 5110 5111 5112 5113 5114 | assert( n<=pTab->nCol ); } }else{ sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName); } #ifndef SQLITE_OMIT_AUTOMATIC_INDEX if( (pLevel->plan.wsFlags & WHERE_TEMP_INDEX)!=0 ){ | | | | 5104 5105 5106 5107 5108 5109 5110 5111 5112 5113 5114 5115 5116 5117 5118 5119 5120 5121 5122 5123 5124 5125 5126 5127 5128 5129 5130 5131 5132 | assert( n<=pTab->nCol ); } }else{ sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName); } #ifndef SQLITE_OMIT_AUTOMATIC_INDEX if( (pLevel->plan.wsFlags & WHERE_TEMP_INDEX)!=0 ){ constructAutomaticIndex(pParse, sWBI.pWC, pTabItem, notReady, pLevel); }else #endif if( (pLevel->plan.wsFlags & WHERE_INDEXED)!=0 ){ Index *pIx = pLevel->plan.u.pIdx; KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIx); int iIndexCur = pLevel->iIdxCur; assert( pIx->pSchema==pTab->pSchema ); assert( iIndexCur>=0 ); sqlite3VdbeAddOp4(v, OP_OpenRead, iIndexCur, pIx->tnum, iDb, (char*)pKey, P4_KEYINFO_HANDOFF); VdbeComment((v, "%s", pIx->zName)); } sqlite3CodeVerifySchema(pParse, iDb); notReady &= ~getMask(sWBI.pWC->pMaskSet, pTabItem->iCursor); } pWInfo->iTop = sqlite3VdbeCurrentAddr(v); if( db->mallocFailed ) goto whereBeginError; /* Generate the code to do the search. Each iteration of the for ** loop below generates code for a single nested loop of the VM ** program. |
︙ | ︙ | |||
5150 5151 5152 5153 5154 5155 5156 5157 5158 5159 5160 5161 5162 5163 | ** the index is listed as "{}". If the primary key is used the ** index name is '*'. */ for(i=0; i<nTabList; i++){ char *z; int n; int w; pLevel = &pWInfo->a[i]; w = pLevel->plan.wsFlags; pTabItem = &pTabList->a[pLevel->iFrom]; z = pTabItem->zAlias; if( z==0 ) z = pTabItem->pTab->zName; n = sqlite3Strlen30(z); if( n+nQPlan < sizeof(sqlite3_query_plan)-10 ){ | > > | 5146 5147 5148 5149 5150 5151 5152 5153 5154 5155 5156 5157 5158 5159 5160 5161 | ** the index is listed as "{}". If the primary key is used the ** index name is '*'. */ for(i=0; i<nTabList; i++){ char *z; int n; int w; struct SrcList_item *pTabItem; pLevel = &pWInfo->a[i]; w = pLevel->plan.wsFlags; pTabItem = &pTabList->a[pLevel->iFrom]; z = pTabItem->zAlias; if( z==0 ) z = pTabItem->pTab->zName; n = sqlite3Strlen30(z); if( n+nQPlan < sizeof(sqlite3_query_plan)-10 ){ |
︙ | ︙ |