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Message-ID: <5056AC9E.4040909@ringerc.id.au>
Date: Mon, 17 Sep 2012 12:52:46 +0800
From: Craig Ringer <ringerc@ringerc.id.au>
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To: Rodrigo Rosenfeld Rosas <rr.rosas@gmail.com>
CC: Gavin Flower <GavinFlower@archidevsys.co.nz>,
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Subject: Re: ORDER BY COLUMN_A, (COLUMN_B or COLUMN_C), COLUMN_D
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On 09/13/2012 07:20 AM, Rodrigo Rosenfeld Rosas wrote:

> Thank you Gavin, I was looking for this LEAST function for a long time.
> I have tried MIN but it didn't work with strings.

In SQL, "MIN" is an aggregate function. It actually does work with 
strings, but only when used as an aggregate:

regress=# SELECT min(x.a) FROM ( VALUES ('blah'),('blah2'),('aaaa') ) x(a);
  min
------
  aaaa
(1 row)

--
Craig Ringer