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To: Rod Taylor <rbt@rbt.ca>
Cc: daniel alvarez <d-alvarez@gmx.de>, pgsql-sql@postgresql.org
Subject: Re: Atomicity of UPDATE, interchanging values in unique 
In-reply-to: <1047160571.28251.202.camel@jester> 
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Comments: In-reply-to Rod Taylor <rbt@rbt.ca>
	message dated "08 Mar 2003 16:56:11 -0500"
Date: Sat, 08 Mar 2003 17:10:44 -0500
Message-ID: <12296.1047161444@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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>> There must be a better solution than the additional dummy update.

How about swapping all the other columns, and preserving the identity of
the primary key?  Arguably, swapping primary keys is a violation of the
relational model to begin with.

			regards, tom lane