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From: Josh Berkus <josh@agliodbs.com>
Organization: Aglio Database Solutions
To: C F <tacnaboyz@yahoo.com>, pgsql-sql@postgresql.org
Subject: Re: SQL Help
Date: Fri, 30 May 2003 09:37:12 -0700
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CF,

> select
>   (case when column1 = column2 then column3 end) as alias1,
>   (case when column1 = column2 then column4 end) as alias2,
>   (case when column1 = column2 then column5 end) as alias3,
>   (case when column6 = column7 then column8 end) as alias4
> from
>   mytable

Given the information you've given us (including your first e-mail), I can't 
think of a better way to get the output you want than the above.  You could 
work through subselects, etc, but I think that would be even less efficient.

One thing you might want to think about is your whole approach to designing 
this application; it may be that you can simplify your queries by changing 
your table design.  

-- 
Josh Berkus
Aglio Database Solutions
San Francisco