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Overview
| Comment: | Remove an unused variable. Fix code that occurs before a variable declaration. |
|---|---|
| Downloads: | Tarball | ZIP archive |
| Timelines: | family | ancestors | descendants | both | trunk |
| Files: | files | file ages | folders |
| SHA1: |
01dc032b5bbd9c9ebb1965f176ca5d73 |
| User & Date: | drh 2012-10-09 01:39:25.125 |
Context
|
2012-10-09
| ||
| 09:26 | Bring some comments up to date in the query planner, and especially the ORDER BY optimizer. Also add testcase() macros. (check-in: bb5c0f1c92 user: drh tags: trunk) | |
| 01:39 | Remove an unused variable. Fix code that occurs before a variable declaration. (check-in: 01dc032b5b user: drh tags: trunk) | |
| 01:23 | Replace an always-false conditional with an assert(). (check-in: 981b9943e4 user: drh tags: trunk) | |
Changes
Changes to src/where.c.
| ︙ | ︙ | |||
3061 3062 3063 3064 3065 3066 3067 |
/* 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) */
| < < < < < < | 3061 3062 3063 3064 3065 3066 3067 3068 3069 3070 3071 3072 3073 3074 |
/* 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) */
/* The following variables are populated based on the properties of
** index being evaluated. They are then used to determine the expected
** cost and number of rows returned.
**
** pc.plan.nEq:
** Number of equality terms that can be implemented using the index.
|
| ︙ | ︙ | |||
3148 3149 3150 3151 3152 3153 3154 3155 3156 3157 3158 3159 3160 3161 |
int nPriorSat; /* ORDER BY terms satisfied by outer loops */
int nOrderBy; /* Number of ORDER BY terms */
WhereTerm *pTerm; /* A single term of the WHERE clause */
#ifdef SQLITE_ENABLE_STAT3
WhereTerm *pFirstTerm = 0; /* First term matching the index */
#endif
memset(&pc, 0, sizeof(pc));
nOrderBy = p->pOrderBy ? p->pOrderBy->nExpr : 0;
if( p->i ){
nPriorSat = pc.plan.nOBSat = p->aLevel[p->i-1].plan.nOBSat;
bSort = nPriorSat<nOrderBy;
bDist = 0;
}else{
| > > > > | 3142 3143 3144 3145 3146 3147 3148 3149 3150 3151 3152 3153 3154 3155 3156 3157 3158 3159 |
int nPriorSat; /* ORDER BY terms satisfied by outer loops */
int nOrderBy; /* Number of ORDER BY terms */
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));
nOrderBy = p->pOrderBy ? p->pOrderBy->nExpr : 0;
if( p->i ){
nPriorSat = pc.plan.nOBSat = p->aLevel[p->i-1].plan.nOBSat;
bSort = nPriorSat<nOrderBy;
bDist = 0;
}else{
|
| ︙ | ︙ | |||
3234 3235 3236 3237 3238 3239 3240 |
}
/* 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 pc.plan.wsFlags. Otherwise, if there is an ORDER BY clause but
** the index will scan rows in a different order, set the bSort
** variable. */
| < | 3232 3233 3234 3235 3236 3237 3238 3239 3240 3241 3242 3243 3244 3245 |
}
/* 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 pc.plan.wsFlags. Otherwise, if there is an ORDER BY clause but
** the index will scan rows in a different order, set the bSort
** variable. */
if( bSort && (pSrc->jointype & JT_LEFT)==0 ){
int bRev = 2;
WHERETRACE((" --> before isSortingIndex: nPriorSat=%d\n",nPriorSat));
pc.plan.nOBSat = isSortingIndex(p, pProbe, iCur, &bRev);
WHERETRACE((" --> after isSortingIndex: bRev=%d nOBSat=%d\n",
bRev, pc.plan.nOBSat));
if( nPriorSat<pc.plan.nOBSat || (pc.plan.wsFlags & WHERE_UNIQUE)!=0 ){
|
| ︙ | ︙ |