Many hyperlinks are disabled.
Use anonymous login
to enable hyperlinks.
Overview
| Comment: | Fix an incorrect cost computation for sorting (introduced just a few check-ins ago). Should be NlogN, not NloglogN. |
|---|---|
| Downloads: | Tarball | ZIP archive | SQL archive |
| Timelines: | family | ancestors | descendants | both | trunk |
| Files: | files | file ages | folders |
| SHA1: |
2459d3238853951bc3a507dd975e7ec9 |
| User & Date: | drh 2016-02-25 23:21:41 |
Context
|
2016-02-25
| ||
| 23:25 | Add tool for smoke-testing the UWP VSIX package. check-in: d27f32c6 user: mistachkin tags: trunk | |
| 23:21 | Fix an incorrect cost computation for sorting (introduced just a few check-ins ago). Should be NlogN, not NloglogN. check-in: 2459d323 user: drh tags: trunk | |
| 21:38 | Small optimization in FK handling. check-in: e0d25913 user: mistachkin tags: trunk | |
Changes
Changes to src/where.c.
3459 3460 3461 3462 3463 3464 3465 3466 3467 3468 3469 3470 3471 3472 3473 3474 3475 |
LogEst rScale, rSortCost;
assert( nOrderBy>0 && 66==sqlite3LogEst(100) );
rScale = sqlite3LogEst((nOrderBy-nSorted)*100/nOrderBy) - 66;
rSortCost = nRow + rScale + 16;
/* Multiple by log(M) where M is the number of output rows.
** Use the LIMIT for M if it is smaller */
if( (pWInfo->wctrlFlags & WHERE_USE_LIMIT)!=0 ){
LogEst m = sqlite3LogEst(pWInfo->iLimit);
if( m<nRow ) nRow = m;
}
rSortCost += estLog(nRow);
return rSortCost;
}
/*
** Given the list of WhereLoop objects at pWInfo->pLoops, this routine
|
| | < |
3459 3460 3461 3462 3463 3464 3465 3466 3467 3468 3469 3470 3471 3472 3473 3474 |
LogEst rScale, rSortCost; assert( nOrderBy>0 && 66==sqlite3LogEst(100) ); rScale = sqlite3LogEst((nOrderBy-nSorted)*100/nOrderBy) - 66; rSortCost = nRow + rScale + 16; /* Multiple by log(M) where M is the number of output rows. ** Use the LIMIT for M if it is smaller */ if( (pWInfo->wctrlFlags & WHERE_USE_LIMIT)!=0 && pWInfo->iLimit<nRow ){ nRow = pWInfo->iLimit; } rSortCost += estLog(nRow); return rSortCost; } /* ** Given the list of WhereLoop objects at pWInfo->pLoops, this routine |
Changes to test/where.test.
569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 |
}
} {1 100 4 2 99 9 3 98 16 nosort}
do_test where-6.6 {
cksort {
SELECT * FROM t3 WHERE a>0 ORDER BY a LIMIT 3
}
} {1 100 4 2 99 9 3 98 16 nosort}
do_test where-6.7 {
cksort {
SELECT * FROM t3 WHERE b>0 ORDER BY a LIMIT 3
}
} {1 100 4 2 99 9 3 98 16 nosort}
ifcapable subquery {
do_test where-6.8a {
cksort {
SELECT * FROM t3 WHERE a IN (3,5,7,1,9,4,2) ORDER BY a LIMIT 3
}
} {1 100 4 2 99 9 3 98 16 nosort}
do_test where-6.8b {
|
| | | > > > > > > |
569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 |
}
} {1 100 4 2 99 9 3 98 16 nosort}
do_test where-6.6 {
cksort {
SELECT * FROM t3 WHERE a>0 ORDER BY a LIMIT 3
}
} {1 100 4 2 99 9 3 98 16 nosort}
do_test where-6.7.1 {
cksort {
SELECT * FROM t3 WHERE b>0 ORDER BY a LIMIT 10
}
} {/1 100 4 2 99 9 3 98 16 .* nosort/}
do_test where-6.7.2 {
cksort {
SELECT * FROM t3 WHERE b>0 ORDER BY a LIMIT 1
}
} {1 100 4 sort}
exit
ifcapable subquery {
do_test where-6.8a {
cksort {
SELECT * FROM t3 WHERE a IN (3,5,7,1,9,4,2) ORDER BY a LIMIT 3
}
} {1 100 4 2 99 9 3 98 16 nosort}
do_test where-6.8b {
|