[MDEV-4345] Fix table selectivity by sampling some probably very selective predicates Created: 2013-04-01 Updated: 2015-05-20 Resolved: 2013-05-07 |
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| Status: | Closed |
| Project: | MariaDB Server |
| Component/s: | None |
| Fix Version/s: | None |
| Type: | Task | Priority: | Major |
| Reporter: | Oleksandr Byelkin | Assignee: | Oleksandr Byelkin |
| Resolution: | Fixed | Votes: | 0 |
| Labels: | None | ||
| Issue Links: |
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| Description |
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There are some predicates like 'table.field LIKE %WORD' which probably very selective but it is impossible judge about them by index or other statistics we collect now. We can just check the predicate against some rows in the table. In the beginning it will be first N rows of the table. |
| Comments |
| Comment by Oleksandr Byelkin [ 2013-04-18 ] |
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pushed to lp:~maria-captains/maria/maria-10.0-mwl253 |
| Comment by Elena Stepanova [ 2015-05-20 ] |
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It was implemented in 10.0.3 (cannot set the 'Fix version' field because 10.0.3 is archived). |