Correction of best way to fetch next/prev record based on index

From: Markus Schaber <schabios(at)logi-track(dot)com>
To: "Merlin Moncure" <merlin(dot)moncure(at)rcsonline(dot)com>
Cc: <pgsql-performance(at)postgresql(dot)org>
Subject: Correction of best way to fetch next/prev record based on index
Date: 2004-07-27 14:21:17
Message-ID: 20040727162117.6de666b6@kingfisher.intern.logi-track.com
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Hi, Merlin,

On Tue, 27 Jul 2004 16:13:25 +0200, I myself wrote:

> You mut not

Should be "must", not "mut" :-)

> > My problem is deceptively simple: how you read the next record from
> > a table based on a given set of values? In practice, this is
> > difficult to implement. If anybody can suggest a alternative/better
> > way to this, I'm all ears.
>
> So you really want something like
>
> 'SELECT * FROM t WHERE a>=a1 AND b>=b1 AND c>=c1 ORDER BY a,b,c ASC
> LIMIT 1'

Sorry, as you want the _next_, and I assume that a1, b1 and c1 are the
current row's values, you should rather use something like:

'SELECT * FROM t WHERE a>=a1 AND b>=b1 AND c>=c1 ORDER BY a,b,c ASC
LIMIT 1 OFFSET 1'

HTH,
Markus

--
markus schaber | dipl. informatiker
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phone +41-43-888 62 52 | fax +41-43-888 62 53
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