Re: Re: [GENERAL] Question regarding new windowing functions in 8.4devel

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От David Fetter
Тема Re: Re: [GENERAL] Question regarding new windowing functions in 8.4devel
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Msg-id 20090116173306.GC20296@fetter.org
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Ответ на Re: Re: [GENERAL] Question regarding new windowing functions in 8.4devel  ("Jaime Casanova" <jcasanov@systemguards.com.ec>)
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On Fri, Jan 16, 2009 at 12:23:16PM -0500, Jaime Casanova wrote:
> On Fri, Jan 16, 2009 at 12:07 PM, David Fetter <david@fetter.org> wrote:
> >>
> >> Now i want only 3 records for every typ:
> >>
> >> test=# select typ, ts, rank() over (partition by typ order by ts desc )  from foo where rank <= 3;
> >> ERROR:  column "rank" does not exist
> >> LINE 1: ...rtition by typ order by ts desc )  from foo where rank <= 3;
>
> maybe the rank should go in a having clause? i'm not familiar about
> window functions yet... just guessing...

I tried HAVING, too, and it's epic fail. :(

> > ERROR:  syntax error at or near "WHERE"
> > LINE 8: WHERE
> >        ^
>
> the WINDOW specification goes after the WHERE clause not before

Thanks :)

Still remaining is our inability to limit windowing functions other
than via subselect or equivalently CTEs.  I believe this is a bug.

Cheers,
David.
--
David Fetter <david@fetter.org> http://fetter.org/
Phone: +1 415 235 3778  AIM: dfetter666  Yahoo!: dfetter
Skype: davidfetter      XMPP: david.fetter@gmail.com

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