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To: Christoph Haller <ch@rodos.fzk.de>
Cc: pgsql-sql@postgresql.org, fernando@icreativa.com.mx,
	gsstark@MIT.EDU
Subject: Re: SETOF
References: <3E65F78E.7455651B@rodos.fzk.de>
In-Reply-To: <3E65F78E.7455651B@rodos.fzk.de>
From: Greg Stark <gsstark@mit.edu>
Organization: The Emacs Conspiracy; member since 1992
Date: 05 Mar 2003 08:36:29 -0500
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Christoph Haller <ch@rodos.fzk.de> writes:

> >
> >
> > Christoph Haller <ch@rodos.fzk.de> writes:
> >
> > > You cannot obtain several columns from SQL functions.
> > > See the list archives (search for SETOF) for details.
> > > You have to use e.g. a plpgsql function instead.
> >
> > How do you do it with a plpgsql function?
>
> And Greg, refer to
> http://techdocs.postgresql.org/guides/SetReturningFunctions
> 
> I think it will fit your needs.

That document describes using the function in the from list of the select.
That's equivalent to converting the query to a join, which isn't always
possible or convenient. I was talking about using a subquery or function in
the output column list to produce multiple output columns.

I'm sorry I may have muddied the waters in that it sounds like my comment
wasn't about exactly the same issue as Chistoph's. 

-- 
greg