MySQL Forums
Forum List  »  Optimizer & Parser

Re: Why not use index
Posted by: Øystein Grøvlen
Date: November 10, 2015 10:35AM

Hi,

Are you sure it is not using the index? When I try a similar example, the Extra column of EXPLAIN says "Range checked for each record". This means that for each row of the left hand table, it will evaluate whether it is beneficial to use the index or not. (In this case, it will probably always be).

I agree that MySQL could be better at handling OR-expressions in ON-clauses. You can file a bug at bugs.mysql.com if you would like us to consider this feature.

Øystein Grøvlen,
Senior Principal Software Engineer,
MySQL Group, Oracle,
Trondheim, Norway

Options: ReplyQuote


Subject
Views
Written By
Posted
1695
November 08, 2015 11:14PM
858
November 09, 2015 11:42AM
868
November 11, 2015 12:17AM
Re: Why not use index
900
November 10, 2015 10:35AM
1053
November 11, 2015 12:15AM
942
November 11, 2015 03:40AM
1197
November 11, 2015 07:29PM
836
November 11, 2015 11:00PM
930
November 12, 2015 01:48AM
898
November 16, 2015 12:17AM


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.