Re: merge result sets

On Mit, 2006-06-21 at 14:16 +0200, Martijn van Oosterhout wrote:
> On Wed, Jun 21, 2006 at 02:08:29PM +0200, simon wrote:
> > > The aggregate stuff should work. something like:
> > >
> > > SET kategorie = (SELECT comma_aggregate(kategorie_bezeichnung) FROM ...)
> > >
> > > should do the trick.
> > i just found
> >
> > CREATE FUNCTION comma_aggregate(text,text) RETURNS text AS ' SELECT CASE
> > WHEN $1 <> '''' THEN $1 || '', '' || $2 ELSE $2 END; ' LANGUAGE sql
> > IMMUTABLE STRICT; CREATE AGGREGATE comma (basetype=text,
> > sfunc=comma_aggregate, stype=text, initcond='' );
> >
> > and this didn't work with the above mentioned querry.
> >
> > i actually never found any docu about how tor write custom function
> > which takes a whole result set no matter how many rows.
>
> Then you havn't looked very hard:
>
> http://www.postgresql.org/docs/current/interactive/sql-createaggregate.html
>
> You created an aggregate called "comma" so that's how you should call
> it. This is really no different from the SQL standard min(), max() and
> sum() functions.
>
> SET kategorie = (SELECT comma(kategorie_bezeichnung) FROM ...)
>
> Have a nice day,

thanks very much. you're right i should have read the docu harder. but
now everthing works fine.
you made my day.

simon

--
Simon Litwan                               simon.litwan@wyona.com
Wyona Inc.  -   Open Source Content Management   -   Apache Lenya
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