Re: IF condition

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#982

From: Craig Stuntz TeamB
Date: Wed, 04 Apr 2007 14:53

21 lines
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aleplgr wrote:

> IF (SELECT COUNT(*) FROM TEMP WHERE (FLAG = 1) > 0) THEN
> BEGIN
> ...
> END

	*Don't* do this. It's *hugely* inefficient. Instead, do:

IF (EXISTS (SELECT 1 FROM TEMP WHERE (FLAG = 1)) THEN BEGIN

	Your version counts all records visible to your transaction, then
throws the result away.

	My version stops as soon as it finds one.

-- 
Craig Stuntz [TeamB] � Vertex Systems Corp. � Columbus, OH
  Delphi/InterBase Weblog : http://blogs.teamb.com/craigstuntz
Borland newsgroup denizen Sergio Gonz�lez has a new CD of 
  Irish music out, and it's good: http://tinyurl.com/7hgfr

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Subject: Re: IF condition
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