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To: Markus Schaber <schabi@logix-tt.com>
Cc: pgsql-performance@postgresql.org,  pgsql-hackers@postgresql.org
Subject: Re: qsort again (was Re: [PERFORM] Strange Create Index
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From: Greg Stark <gsstark@mit.edu>
Organization: The Emacs Conspiracy; member since 1992
Date: 16 Feb 2006 17:51:02 -0500
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Markus Schaber <schabi@logix-tt.com> writes:

> Hmm, to remove redundancy, I'd change the <= to a < and define:
> 
> if a==b then f(a)==f(b)
> if a<b  then f(a)<=f(b)
> 
> > Data types which could probably provide a useful function for f would be
> > int2, int4, oid, and possibly int8 and text (at least for SQL_ASCII).

How exactly do you imagine doing this for text?

I could see doing it for char(n)/varchar(n) where n<=4 in SQL_ASCII though.

-- 
greg