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Re: MySQL rand() is slow on large datasets
Posted by: Thomas Baggelaar
Date: July 24, 2007 08:28AM

Maybe this can help you with your performance issue

This query:

SELECT * FROM `table` WHERE id >= (SELECT FLOOR( MAX(id) * RAND()) FROM `table` ) ORDER BY id LIMIT 1;

should be much faster than this query:

SELECT * FROM `table` ORDER BY RAND() LIMIT 1;

See also: http://forums.mysql.com/read.php?10,163708,163708#msg-163708

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MySQL rand() is slow on large datasets
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pbu pbu
July 24, 2007 08:19AM
Re: MySQL rand() is slow on large datasets
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Thomas Baggelaar
July 24, 2007 08:28AM
Re: MySQL rand() is slow on large datasets
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Maurizio G
September 02, 2007 10:30AM
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Jay Paroline
January 18, 2008 12:25AM
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Jeff Fillmore
May 15, 2008 03:15PM
Re: MySQL rand() is slow on large datasets
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Mike Pogues
May 12, 2009 10:21AM


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