Re: strange stable function behavior

Thank you very much. It works!!!
Where can I read about such features?

2006/6/1, Martijn van Oosterhout <kleptog(at)svana(dot)org>:
>
> On Thu, Jun 01, 2006 at 03:09:47PM +0400, Dan Black wrote:
> > Hi
> > I have a stable function test.test_stable
>
> <snip>
>
> > But if I want to display field sid twice
> >
> > SELECT id, sid, sid FROM
> > (SELECT *, test.test_stable(id) AS sid FROM generate_series(10, 100) AS
> id)
> > tbl
> >
> > I can see that function test.test_stable executes twice with identical
> > parameters
>
> Postgres makes no special effort to avoid multiple calls of the same
> function. Especially since you declared it STABLE.
>
> > Is it bug or special feature?
>
> Not a bug nor a special feature, just the way it is. If you put OFFSET 0
> in the subquery, that will stop the expansion of the subquery, thus the
> function will only be called once.
>
> Have a nice day,
> --
> Martijn van Oosterhout <kleptog(at)svana(dot)org> http://svana.org/kleptog/
> > From each according to his ability. To each according to his ability to
> litigate.
>
>
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--
Verba volent, scripta manent
Dan Black