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Re: distinct clause issue for 600000 records
Posted by: Øystein Grøvlen
Date: November 16, 2015 05:54AM

Hi,

I agree that IN-subqueries are better than DISTINCT. Avoiding duplicates in the first place will perform better than removing them afterwards. With MySQL 5.6 it should perform better, IN-subqueries should have better performance than before.

I still do not understand what cardinality length is.

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

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