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Checking existence query?

Mr. C Lamont Gilbert
Ranch Hand

Joined: Oct 05, 2001
Posts: 1170

All I want to know is if Name is not null. I have a unique constraint on my name so I need to ensure none exists which is the same as the one I plan to use.

I am using

and to tell me if such a name exists or not. Is there a better query for this since I am not even looking at the returned name, only if it exists or not.
Jeanne Boyarsky
author & internet detective

Joined: May 26, 2003
Posts: 33132

This version is slightly more efficient because the database doesn't have to return as much data.

Did you want a unique name in general or per component id? The unique index would do it for name only.

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subject: Checking existence query?
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