Bug #26915 | Slow quering due to optimizer choosing incorrect index utilisation | ||
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Submitted: | 7 Mar 2007 11:54 | Modified: | 21 Apr 2007 14:04 |
Reporter: | Jacques | Email Updates: | |
Status: | No Feedback | Impact on me: | |
Category: | MySQL Server: Optimizer | Severity: | S5 (Performance) |
Version: | 5.0.27 | OS: | Linux (Redhat Linux RHEL4) |
Assigned to: | CPU Architecture: | Any | |
Tags: | mysql innodb merge index intercept filesort |
[7 Mar 2007 11:54]
Jacques
[7 Mar 2007 13:29]
Valeriy Kravchuk
Thank you for a problem report. Please, send the results of SHOW TABLE STATUS for the table involved, and the results of: select count(*) from t1 where c1 = 1; select count(*) from t1 where с2 = 2; (substitute your real table name and column names). Filesort is used because index on id column (primary key) is not used by optimizer.
[7 Mar 2007 14:59]
Valeriy Kravchuk
Please, repeat the query as you planned and send the results. Have you ever run ANALYZE TABLE for the table used in query?
[21 Mar 2007 14:04]
Valeriy Kravchuk
Please, try to repeat with a newer version, 5.0.37, and run ANALYZE TABLE before the quesry. Inform about the results.
[21 Apr 2007 23:00]
Bugs System
No feedback was provided for this bug for over a month, so it is being suspended automatically. If you are able to provide the information that was originally requested, please do so and change the status of the bug back to "Open".