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Re: add a correct index, the same select statement becomes 5 times slower
Posted by: shahbaz khan
Date: August 16, 2009 11:47AM

Two things.. Firstly write this query like this
SELECT * FROM down_messages WHERE msg_id>0 AND msg_type='4' AND
to_id IN ('o1803','all','f2222231','f82006573','o1803|1234','l1','l1|o1803','l1|o1803','l1|o1803','l1|o1803','l1|o1803','l1|o1803','l1|o1803','l1|o1803','l1|o1803','l1|o1803','l1|o1803','l1|o1803')
AND begin_time<=NOW() AND end_time>=NOW()
GROUP BY msg_id
ORDER BY msg_id

Secondly putting index on date is not good practice.
Try putting index one by one starting from msg_d.It should improve.

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add a correct index, the same select statement becomes 5 times slower
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qiu cheng
May 27, 2009 07:51PM
Re: add a correct index, the same select statement becomes 5 times slower
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shahbaz khan
August 16, 2009 11:47AM
Re: add a correct index, the same select statement becomes 5 times slower
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Rick James
August 16, 2009 03:54PM


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