Re: Slow query
What version of MySQL?
Exists( Select ... ) can be slow.
OR in the Where clause may not optimise well, depending on the engine and the version.
If you don't get satisfactoty results from changing In(Select...) to Join, and writing the two queries as Unions rather than Ors, post the Explain Extended results, Show Create Table results (not Describe!) and Show Tabke Status results for each table
Subject
Views
Written By
Posted
1884
December 11, 2015 01:00PM
Re: Slow query
879
December 11, 2015 05:00PM
844
December 11, 2015 06:56PM
789
December 12, 2015 07:34AM
886
December 14, 2015 02:34AM
716
December 15, 2015 08:48AM
778
December 15, 2015 10:57AM
901
December 16, 2015 02:33AM
Sorry, you can't reply to this topic. It has been closed.
Content reproduced on this site is the property of the respective copyright holders.
It is not reviewed in advance by Oracle and does not necessarily represent the opinion
of Oracle or any other party.