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Re: Count massively faster than select on same query, why?!?!
Posted by: Bob Field
Date: August 03, 2006 03:21PM

count(*) can count the rows using the index only. Especially in MyISAM tables, this means the MYD file didn't have to be opened, and provides a substantial performance increase. In your case the biggest expense is not satisfying the WHERE clause but actually retrieving the data.

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