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From Daniel Noll <dan...@nuix.com>
Subject COUNT() optimisation
Date Thu, 07 Feb 2008 22:25:35 GMT
Hi all.

COUNT() is constant performance if you count all the rows in a table, but 
linear performance if you have a condition on which rows should be counted.

Is there any way to optimise the latter case?  I know that indexing on the 
columns used in the query doesn't work.

Daniel

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