MySQL: how to index an "OR" clause

Posted by JoséMi on Stack Overflow See other posts from Stack Overflow or by JoséMi
Published on 2010-05-13T19:09:47Z Indexed on 2010/05/13 19:14 UTC
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Filed under:

mysql

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index

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where

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composite

I'm executing the following query

SELECT COUNT(*) FROM table WHERE field1='value' AND (field2 >= 1000 OR field3 >= 2000)

There is one index over field1 and another composited over field2&field3.

I see MySQL always selects the field1 index and then makes a join using the other two fields which is quite bad because it needs to join 146.000 rows.

Suggestions on how to improve this? Thanks

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