Bug #72518 | UPDATE ORDER BY does a filesort if updating a column in the index | ||
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Submitted: | 2 May 2014 23:42 | Modified: | 30 Aug 2015 20:59 |
Reporter: | Harrison Fisk | Email Updates: | |
Status: | Closed | Impact on me: | |
Category: | MySQL Server: Optimizer | Severity: | S5 (Performance) |
Version: | 5.6.16 | OS: | Any |
Assigned to: | CPU Architecture: | Any | |
Tags: | filesort, Optimizer |
[2 May 2014 23:42]
Harrison Fisk
[30 Aug 2015 20:59]
Paul DuBois
Noted in 5.7.9, 5.8.0 changelogs. For UPDATE statements with ORDER BY, the optimizer could perform an unnecessary filesort on a key that was used for scanning as well as being updated.