Message-ID: <387C22290D3FD71195D300508BF7DB5238B017@colmail01.cranel.local>
From: "Spiegelberg, Greg" <gspiegelberg@cranel.com>
To: 'Richard Huxton' <dev@archonet.com>, Andrei Bintintan <klodoma@ar-sd.net>
Cc: pgsql-sql@postgresql.org, pgsql-performance@postgresql.org
Subject: Re: [SQL] OFFSET impact on Performance???
Date: Thu, 20 Jan 2005 13:04:02 -0500
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Isn't this a prime example of when to use a servlet or something similar
in function?  It will create the cursor, maintain it, and fetch against
it for a particular page.

Greg


-----Original Message-----
From: Richard Huxton [mailto:dev@archonet.com]
Sent: Thursday, January 20, 2005 10:21 AM
To: Andrei Bintintan
Cc: pgsql-sql@postgresql.org; pgsql-performance@postgresql.org
Subject: Re: [PERFORM] [SQL] OFFSET impact on Performance???


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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