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Re: Rows Examined, why so many?
Posted by: Jay Pipes
Date: September 20, 2005 03:54PM

Daniel is correct. Also remember that the EXPLAIN SELECT output is only a *guess* made by the optimizer regarding what it believes will be the number of index records which will match the search criteria, based on the info MySQL has regarding the distribution of keys in the index. The actual number of rows returned, as you saw, can be different.

Jay Pipes
Community Relations Manager, North America, MySQL Inc.

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