To: alex@neteconomist.com
Cc: Richard Huxton <dev@archonet.com>,
	Andrei Bintintan <klodoma@ar-sd.net>, pgsql-sql@postgresql.org,
	pgsql-performance@postgresql.org
Subject: Re: [SQL] OFFSET impact on Performance???
References: <019f01c4fee1$1b58d600$0b00a8c0@forge>
	<41EF9FD3.5020400@archonet.com> <020d01c4fef6$595bb9d0$0b00a8c0@forge>
	<41EFCC5B.5010302@archonet.com>
	<33c6269f05012008391490448b@mail.gmail.com>
In-Reply-To: <33c6269f05012008391490448b@mail.gmail.com>
From: Greg Stark <gsstark@mit.edu>
Organization: The Emacs Conspiracy; member since 1992
Date: 25 Jan 2005 13:28:46 -0500
Message-ID: <87y8eh1hy9.fsf@stark.xeocode.com>
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Alex Turner <armtuk@gmail.com> writes:

> I am also very interesting in this very question.. Is there any way to
> declare a persistant cursor that remains open between pg sessions? 
> This would be better than a temp table because you would not have to
> do the initial select and insert into a fresh table and incur those IO
> costs, which are often very heavy, and the reason why one would want
> to use a cursor.

TANSTAAFL. How would such a persistent cursor be implemented if not by
building a temporary table somewhere behind the scenes?

There could be some advantage if the data were stored in a temporary table
marked as not having to be WAL logged. Instead it could be automatically
cleared on every database start.

-- 
greg