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Message-ID: <33c6269f05012008391490448b@mail.gmail.com>
Date: Thu, 20 Jan 2005 11:39:16 -0500
From: Alex Turner <armtuk@gmail.com>
Reply-To: alex@neteconomist.com
To: Richard Huxton <dev@archonet.com>
Subject: Re: [SQL] OFFSET impact on Performance???
Cc: Andrei Bintintan <klodoma@ar-sd.net>, pgsql-sql@postgresql.org,
	pgsql-performance@postgresql.org
In-Reply-To: <41EFCC5B.5010302@archonet.com>
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References: <019f01c4fee1$1b58d600$0b00a8c0@forge>
	<41EF9FD3.5020400@archonet.com> <020d01c4fef6$595bb9d0$0b00a8c0@forge>
	<41EFCC5B.5010302@archonet.com>

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.

Alex Turner
NetEconomist


On Thu, 20 Jan 2005 15:20:59 +0000, Richard Huxton <dev@archonet.com> wrote:
> Andrei Bintintan wrote:
> >> If you're using this to provide "pages" of results, could you use a
> >> cursor?
> >
> > What do you mean by that? Cursor?
> >
> > Yes I'm using this to provide "pages", but If I jump to the last pages
> > it goes very slow.
> 
> DECLARE mycursor CURSOR FOR SELECT * FROM ...
> FETCH FORWARD 10 IN mycursor;
> CLOSE mycursor;
> 
> Repeated FETCHes would let you step through your results. That won't
> work if you have a web-app making repeated connections.
> 
> If you've got a web-application then you'll probably want to insert the
> results into a cache table for later use.
> 
> --
>    Richard Huxton
>    Archonet Ltd
> 
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