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To: "Marc Mamin" <M.Mamin@intershop.de>
cc: pgsql-performance@postgresql.org
Subject: Re: tuning a function to insert/retrieve values from a reference
	table
In-reply-to: 
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Comments: In-reply-to "Marc Mamin" <M.Mamin@intershop.de>
	message dated "Tue, 10 Jul 2007 17:03:40 +0200"
Date: Tue, 10 Jul 2007 11:41:20 -0400
Message-ID: <20267.1184082080@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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"Marc Mamin" <M.Mamin@intershop.de> writes:
> Can I optimize this function with:

> a) remove the EXCEPTION clause (Is there an underlying lock that prevent
> concurrent inserts ?)

No.

> b) declare the function being IMMUTABLE ?

Certainly not --- it's got side-effects.

			regards, tom lane