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Date: Thu, 18 Oct 2001 20:25:44 -0400
From: Joseph Shraibman <jks@selectacast.net>
Organization: Xtenit, Inc. http://www.xtenit.com
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Subject: index question
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Lets say I have a table with columns a and b.  I want to do a query like
SELECT count(distinct b) WHERE a = 2;

Should I have an index on a or an index on (a,b)?

-- 
Joseph Shraibman
jks@selectacast.net
Increase signal to noise ratio.  http://www.targabot.com