Re: CONCAT and Index in where clause

[Øystein Grøvlen]

Hi,

Indexes do not apply for expressions involving functions over columns. In your specific case, you should be able to use an index if you rewrite the query as follows:

SELECT * from MyTABLE WHERE YEAR='2012' and MONTH='08' and DAY='21';

Hope this helps,

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