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Overview
| Comment: | Factor some work out of the index loop of the bestBtreeIndex() routine for a small performance increase. |
|---|---|
| Downloads: | Tarball | ZIP archive |
| Timelines: | family | ancestors | descendants | both | trunk |
| Files: | files | file ages | folders |
| SHA1: |
92c9ab56b1c67b9468bec57ab1d2c483 |
| User & Date: | drh 2012-12-08 22:14:29.324 |
Context
|
2012-12-10
| ||
| 09:08 | Remove a reference to JumpOnce from a comment in vdbe.c. No code changes. (check-in: ee662c039d user: dan tags: trunk) | |
|
2012-12-08
| ||
| 23:37 | Pull the latest trunk changes into the sessions branch, and in particular the collating-sequence refactorization. (check-in: 4f6d69ae94 user: drh tags: sessions) | |
| 22:14 | Factor some work out of the index loop of the bestBtreeIndex() routine for a small performance increase. (check-in: 92c9ab56b1 user: drh tags: trunk) | |
| 21:51 | Refactor collating-sequence handling as a fix for ticket [71e333e7d2e642]. The Expr.pColl field is removed from the Expr object. The COLLATE operator now becomes a separate instance of Expr in the expression tree. The code generator looks up the correct collating function as needed, rather than referring to Expr.pColl. (check-in: 8542e6180d user: drh tags: trunk) | |
Changes
Changes to src/where.c.
| ︙ | ︙ | |||
3028 3029 3030 3031 3032 3033 3034 3035 3036 3037 3038 3039 3040 3041 | 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 | > > > > > | 3028 3029 3030 3031 3032 3033 3034 3035 3036 3037 3038 3039 3040 3041 3042 3043 3044 3045 3046 | 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 */ int nPriorSat; /* ORDER BY terms satisfied by outer loops */ int nOrderBy; /* Number of ORDER BY terms */ char bSortInit; /* Initializer for bSort in inner loop */ char bDistInit; /* Initializer for bDist in inner loop */ /* 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 |
| ︙ | ︙ | |||
3076 3077 3078 3079 3080 3081 3082 3083 3084 3085 3086 3087 3088 3089 |
pProbe = &sPk;
wsFlagMask = ~(
WHERE_COLUMN_IN|WHERE_COLUMN_EQ|WHERE_COLUMN_NULL|WHERE_COLUMN_RANGE
);
eqTermMask = WO_EQ|WO_IN;
pIdx = 0;
}
/* Loop over all indices looking for the best one to use
*/
for(; pProbe; pIdx=pProbe=pProbe->pNext){
const tRowcnt * const aiRowEst = pProbe->aiRowEst;
WhereCost pc; /* Cost of using pProbe */
double log10N = (double)1; /* base-10 logarithm of nRow (inexact) */
| > > > > > > > > > > > | 3081 3082 3083 3084 3085 3086 3087 3088 3089 3090 3091 3092 3093 3094 3095 3096 3097 3098 3099 3100 3101 3102 3103 3104 3105 |
pProbe = &sPk;
wsFlagMask = ~(
WHERE_COLUMN_IN|WHERE_COLUMN_EQ|WHERE_COLUMN_NULL|WHERE_COLUMN_RANGE
);
eqTermMask = WO_EQ|WO_IN;
pIdx = 0;
}
nOrderBy = p->pOrderBy ? p->pOrderBy->nExpr : 0;
if( p->i ){
nPriorSat = p->aLevel[p->i-1].plan.nOBSat;
bSortInit = nPriorSat<nOrderBy;
bDistInit = 0;
}else{
nPriorSat = 0;
bSortInit = nOrderBy>0;
bDistInit = p->pDistinct!=0;
}
/* Loop over all indices looking for the best one to use
*/
for(; pProbe; pIdx=pProbe=pProbe->pNext){
const tRowcnt * const aiRowEst = pProbe->aiRowEst;
WhereCost pc; /* Cost of using pProbe */
double log10N = (double)1; /* base-10 logarithm of nRow (inexact) */
|
| ︙ | ︙ | |||
3154 3155 3156 3157 3158 3159 3160 |
** SELECT a, b FROM tbl WHERE a = 1;
** SELECT a, b, c FROM tbl WHERE a = 1;
*/
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 */
| | | | < < < < < < < < | < < < | 3170 3171 3172 3173 3174 3175 3176 3177 3178 3179 3180 3181 3182 3183 3184 3185 3186 3187 3188 3189 3190 3191 3192 3193 3194 3195 3196 3197 |
** SELECT a, b FROM tbl WHERE a = 1;
** SELECT a, b, c FROM tbl WHERE a = 1;
*/
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 */
char bSort = bSortInit; /* True if external sort required */
char bDist = bDistInit; /* True if index cannot help with DISTINCT */
char 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
WHERETRACE((
" %s(%s):\n",
pSrc->pTab->zName, (pIdx ? pIdx->zName : "ipk")
));
memset(&pc, 0, sizeof(pc));
pc.plan.nOBSat = nPriorSat;
/* Determine the values of pc.plan.nEq and nInMul */
for(pc.plan.nEq=0; pc.plan.nEq<pProbe->nColumn; pc.plan.nEq++){
int j = pProbe->aiColumn[pc.plan.nEq];
pTerm = findTerm(pWC, iCur, j, p->notReady, eqTermMask, pIdx);
if( pTerm==0 ) break;
pc.plan.wsFlags |= (WHERE_COLUMN_EQ|WHERE_ROWID_EQ);
|
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