Date: Thu, 21 Jul 2005 12:13:34 -0400
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: Erik Wasser <erik.wasser@iquer.net>
Cc: pgsql-sql@postgresql.org
Subject: Re: Are long term never commited SELECT statements are a problem?
Message-ID: <20050721161334.GH24366@alvh.no-ip.org>
References: <200507211557.58822.erik.wasser@iquer.net>
	<20050721151811.GA513@winnie.fuhr.org>
	<200507211740.57999.erik.wasser@iquer.net>
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On Thu, Jul 21, 2005 at 05:40:57PM +0200, Erik Wasser wrote:

> > When a transaction is on the serializable level, a SELECT query sees
> > only data committed before the transaction began; it never sees either
> > uncommitted data or changes committed during transaction execution by
> > concurrent transactions. (However, the SELECT does see the effects of
> > previous updates executed within its own transaction, even though they
> > are not yet committed.)     

> Why do I see in the first transaction data from the commited second 
> transaction? Doesn't prove that the documentation on the above URL 
> wrong?

Because it says "in the serializable level," which they acquire when you
execute "SET TRANSACTION ISOLATION LEVEL SERIALIZABLE".

-- 
Alvaro Herrera (<alvherre[a]alvh.no-ip.org>)
Officer Krupke, what are we to do?
Gee, officer Krupke, Krup you! (West Side Story, "Gee, Officer Krupke")