Re: UPDATE syntax question

From: Ross Presser (rpresser_at_imtek.com)
Date: 02/16/05 

Date: Wed, 16 Feb 2005 10:34:39 -0500

On Tue, 15 Feb 2005 17:26:56 -0500, Mike W wrote:

> How about in an EXISTS clause?
>
> "Gert-Jan Strik" <sorry@toomuchspamalready.nl> wrote in message
> news:42126FB3.F2444DAE@toomuchspamalready.nl...
>> Using "SELECT 1" or "SELECT *" in a (NOT) EXISTS clause does not matter.
>> Their performance is identical.
>>
>> Gert-Jan

Specifically in an EXISTS clause, the optimizer will just test for the
existence of any rows, and not worry about what columns were specified.

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