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Message-ID: <a2de01dd0704262102o3fd14c7r7700a0f20f209e27@mail.gmail.com>
Date: Fri, 27 Apr 2007 05:02:19 +0100
From: "Peter Childs" <peterachilds@gmail.com>
Subject: Re: Selecting rows with "static" ordering
Cc: pgsql-sql@postgresql.org
In-Reply-To: <bf05e51c0704261746m3c6cea8dk7003e3806fd457ca@mail.gmail.com>
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References: <20070427001004.B5F5D9FBABA@postgresql.org>
	<bf05e51c0704261746m3c6cea8dk7003e3806fd457ca@mail.gmail.com>

On 27/04/07, Aaron Bono <postgresql@aranya.com> wrote:
> On 4/26/07, Steve Midgley <public@misuse.org> wrote:
> > So take
> > for example this foreign application variable:
> >
> >    ids = "3,2,5,1,4"
> >
> > The application then executes this sql:
> >
> >    select * from table where id in (3,2,5,1,4)
> >
> > As-is, of course, the above query will return the 5 records in a
> > semi-random (i.e. unpredictable/unreliable) order. And I don't want to
> > just "order by id" - I want to "order by id(3,2,5,1,4)" (if you see
> > what I mean)
> >
> >
>
> select *
> from table
> where id in (3, 2, 5, 1, 4)
> order by
>     case when (id = 3) then 1
>     when (id = 2) then 2
>     when (id = 5) then 3
>     when (id = 1) then 4
>     when (id = 4) then 5
>     else null
>      end
> ;
>

could you not use the values statment of psql 8.2 hmmm

select * from table, values ((1,3),(2,2),(3,5),(4,1),(5,4)) as values
where values.id=table.second order by values.first;

never done it but I think it should work with a bit of playing arond...

Peter.