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Re: distinct clause issue for 600000 records
Posted by: Øystein Grøvlen
Date: November 12, 2015 07:43AM

Hi,

Without seeing the actual query, it is not easy to give any general advice on this. However, the first step should be to consider what LEFT JOINs are strictly necessary. If you use MySQL 5.6, there should be no reason to avoid IN-subqueries. MySQL will be able to convert them into join and remove duplicates automatically if necessary.

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

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