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To: "Mikhail V. Puzanov" <misha.puzanov@gmail.com>
cc: pgsql-sql@postgresql.org
Subject: Re: atomic multi-threaded upsert 
In-reply-to: <4CED72BB.3070905@gmail.com> 
References: <4CED72BB.3070905@gmail.com>
Comments: In-reply-to "Mikhail V. Puzanov" <misha.puzanov@gmail.com>
	message dated "Thu, 25 Nov 2010 02:16:59 +0600"
Date: Wed, 24 Nov 2010 16:21:10 -0500
Message-ID: <21822.1290633670@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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"Mikhail V. Puzanov" <misha.puzanov@gmail.com> writes:
>    -- increment and get the counter if exists
>   UPDATE sequences SET counter = counter + 1
>   WHERE section = 'testSection' AND name = 'testKey'
>   RETURNING counter;

Seems that what you have here is a bad manual implementation of a
sequence.  Why don't you use a real sequence object and nextval()?

			regards, tom lane