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Overview
| Comment: | Fix the computation of the number of rows in a table during automatic index generation. |
|---|---|
| Downloads: | Tarball | ZIP archive | SQL archive |
| Timelines: | family | ancestors | descendants | both | trunk |
| Files: | files | file ages | folders |
| SHA1: |
edeab06a5010c82491a6cc9393cf2a35 |
| User & Date: | drh 2010-04-08 15:01:00 |
Context
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2010-04-08
| ||
| 15:01 | New test cases for automatic indices. New testcase() macros associated with column-used bitmasks. check-in: e1aa48ac user: drh tags: trunk | |
| 15:01 | Fix the computation of the number of rows in a table during automatic index generation. check-in: edeab06a user: drh tags: trunk | |
| 14:38 | Fix an integer overflow bug in the automatic index logic. The bug was detected by the testcase() macros added in the previous check-in. Also add some more testcase() macros, since this issue points up their importance. check-in: af97b488 user: drh tags: trunk | |
Changes
Changes to src/where.c.
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}
if( pSrc->notIndexed ){
/* The NOT INDEXED clause appears in the SQL. */
return;
}
assert( pParse->nQueryLoop >= (double)1 );
nTableRow = pSrc->pIndex ? pSrc->pIndex->aiRowEst[0] : 1000000;
logN = estLog(nTableRow);
costTempIdx = 2*logN*(nTableRow/pParse->nQueryLoop + 1);
if( costTempIdx>=pCost->rCost ){
/* The cost of creating the transient table would be greater than
** doing the full table scan */
return;
}
/* Search for any equality comparison term */
pTable = pSrc->pTab;
pWCEnd = &pWC->a[pWC->nTerm];
for(pTerm=pWC->a; pTerm<pWCEnd; pTerm++){
if( termCanDriveIndex(pTerm, pSrc, notReady) ){
WHERETRACE(("auto-index reduces cost from %.2f to %.2f\n",
pCost->rCost, costTempIdx));
pCost->rCost = costTempIdx;
pCost->nRow = logN + 1;
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}
if( pSrc->notIndexed ){
/* The NOT INDEXED clause appears in the SQL. */
return;
}
assert( pParse->nQueryLoop >= (double)1 );
pTable = pSrc->pTab;
nTableRow = pTable->pIndex ? pTable->pIndex->aiRowEst[0] : 1000000;
logN = estLog(nTableRow);
costTempIdx = 2*logN*(nTableRow/pParse->nQueryLoop + 1);
if( costTempIdx>=pCost->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, notReady) ){
WHERETRACE(("auto-index reduces cost from %.2f to %.2f\n",
pCost->rCost, costTempIdx));
pCost->rCost = costTempIdx;
pCost->nRow = logN + 1;
|