On Tue, Jun 20, 2006 at 12:06:24 +0200,
simon <simon.litwan@wyona.com> wrote:
> hi all
>
> i'm using postgres 7.3
>
> my problem is i want to build a helper table:
>
> UPDATE studienmodul_summary
> SET kategorie = (SELECT kategorie_bezeichnung
>
> if the SELECT gives back just one result row, everthing is easy. my
> problem is, there is sometimes more than one result row.
>
> is there a way to concatenate all result rows and insert them in one
> field?
Yes. You can have the subselect call a custom aggregate function that does
this for you. Sample code for doing this has been posted on the list
multiple times and you should be able to find it in the archives.