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Date: Tue, 04 Mar 2003 21:01:31 +0100
From: Tomasz Myrta <jasiek@klaster.net>
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To: Ian Burrell <ib@onsitetech.com>
Cc: pgsql-sql@postgresql.org
Subject: Re: Sorting by NULL values
References: <3E65023E.10404@onsitetech.com>
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Ian Burrell wrote:
> I am doing a query where I need to sort by a column that may be NULL 
> because it is coming from an OUTER JOIN.  I noticed a difference between
> PostgreSQL and other databases about where NULLs show up.  It seems that 
> with Postgres, NULLs are sorted after other values.  Other databases 
> sort them before.
> 
> Is there any standard on how sorting NULLs work?  Is there a way to 
> change Postgres's behavior?  Is there a way to replace the NULLs with 
> empty strings?
order by field is null asc/desc, field asc/desc

Regards,
Tomasz Myrta