From: Peter Brawley
Date: February 28 2005 6:37pm
Subject: Re: Fwd: how can I do instead of using subselects?
List-Archive: http://lists.mysql.com/mysql/180681
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Joppe,

>Another question is how do I do when I want to compare two tables, 
>normally is it no problem to get a list with rows that exist i both 
>tables, but how do I do if I want to to have the diffrence listed 
>instead, the rows that only appears in one of the tables?

SELECT *
FROM tblA
LEFT JOIN tblB ON tblA.key=tblB.key
WHERE tblB.key IS NULL;

returns the rows of tblA for which there is no tblB row with a matching key value.

Peter Brawley
http://www.artfulsoftware.com



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