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Re: MySQL rand() is slow on large datasets
Posted by: Mike Pogues
Date: May 12, 2009 10:21AM

Tried Jeff's query but only low number ids were generated. The query below solves this.

SELECT t.id FROM table t JOIN (SELECT(FLOOR(max(id) * rand())) as maxid FROM table) as tt on t.id >= tt.maxid LIMIT 1

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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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