Re: Newbie SQL problem with UPDATE - SQL0811 -- MIDRANGE-L

Subject: Re: Newbie SQL problem with UPDATE - SQL0811
From: Charles Wilt <charles.wilt@xxxxxxxxx>
Date: Fri, 10 Apr 2009 15:39:29 -0400
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I normally don't argue with Elvis about SQL performance but....

If most rows have a match, wouldn't COALESCE perform better?

On the other hand, if most rows don't have a match, I could see EXISTS
performing better as long as the right index exists.

Charles

On Fri, Apr 10, 2009 at 3:16 PM, Elvis Budimlic
<ebudimlic@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote:

BTW, for performance reasons, stick with the EXISTS and forget the COALESCE
in this case.

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Follow-Ups:

RE: Newbie SQL problem with UPDATE - SQL0811 , Elvis Budimlic

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