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Overview
| Comment: | Fix problems in the est_count pragma for indexes and WITHOUT ROWID tables. |
|---|---|
| Downloads: | Tarball | ZIP archive |
| Timelines: | family | ancestors | descendants | both | est_count_pragma |
| Files: | files | file ages | folders |
| SHA1: |
c39fd9b8f11b3f1df489df1df4197fe4 |
| User & Date: | drh 2016-10-21 15:36:51.551 |
Context
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2016-10-21
| ||
| 17:25 | Add the btree_sample(INDEX,LOCATION,LIMIT) pragma. (check-in: affc2ef5ee user: drh tags: est_count_pragma) | |
| 15:36 | Fix problems in the est_count pragma for indexes and WITHOUT ROWID tables. (check-in: c39fd9b8f1 user: drh tags: est_count_pragma) | |
|
2016-10-20
| ||
| 22:02 | Experimental est_count pragma. (check-in: 340822afbe user: drh tags: est_count_pragma) | |
Changes
Changes to src/pragma.c.
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1386 1387 1388 1389 1390 1391 1392 |
**
** Seek in <table-or-index> through the first <fraction> of rows and
** estimate the total number of rows based on the path back up to the
** root.
*/
case PragTyp_EST_COUNT: {
Index *pIdx;
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**
** Seek in <table-or-index> through the first <fraction> of rows and
** estimate the total number of rows based on the path back up to the
** root.
*/
case PragTyp_EST_COUNT: {
Index *pIdx;
Table *pTab = 0;
Pgno iRoot = 0;
const char *zName = 0;
int regResult;
double r;
static const char *azCol[] = { "est" };
if( (pIdx = sqlite3FindIndex(db, zRight, zDb))!=0 ){
iRoot = pIdx->tnum;
zName = pIdx->zName;
}else if( (pTab = sqlite3FindTable(db, zRight, zDb))!=0 ){
zName = pTab->zName;
if( HasRowid(pTab) ){
iRoot = pTab->tnum;
}else{
pIdx = sqlite3PrimaryKeyIndex(pTab);
iRoot = pIdx->tnum;
}
}else{
break;
}
sqlite3TableLock(pParse, iDb, iRoot, 0, zName);
regResult = ++pParse->nMem;
setAllColumnNames(v, 1, azCol);
if( pValues->nId>=2 ){
const char *z = pValues->a[1].zName;
sqlite3AtoF(z, &r, sqlite3Strlen30(z), SQLITE_UTF8);
}else{
r = 0.5;
}
if( r<0.0 ) r = 0.0;
if( r>1.0 ) r = 1.0;
sqlite3CodeVerifySchema(pParse, iDb);
pParse->nTab++;
sqlite3VdbeAddOp4Int(v, OP_OpenRead, 0, iRoot, iDb, 1);
if( pIdx ) sqlite3VdbeSetP4KeyInfo(pParse, pIdx);
sqlite3VdbeAddOp3(v, OP_EstRowCnt, 0, regResult, (int)(r*1000000000));
sqlite3VdbeAddOp2(v, OP_ResultRow, regResult, 1);
}
break;
#ifndef SQLITE_INTEGRITY_CHECK_ERROR_MAX
# define SQLITE_INTEGRITY_CHECK_ERROR_MAX 100
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