Re: mySQL performance problem on subqueries
Do you aware that if the query returns 2377 rows, then the subselect is executed 2377 times, not 1 time.
Counting a lot of rows is very fast and constant time in MyISAM but only if there is no Where condition and no Group by, means all rows in the table, this is beacuse the number of rows is stored in the table, so no actual counting is required.
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May 15, 2006 05:14AM
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Re: mySQL performance problem on subqueries
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May 15, 2006 06:17PM
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