problem with automatic altering of groups

"Matthias Nagl" <mnagl(at)web(dot)de> schrieb am 20.08.03 23:09:03:
Hello,

is ist possible to write a function that alters the group of a given user like the following should do in my
opinion (I'd like to use it in a rule):

CREATE FUNCTION set_group (text, integer) RETURNS text AS '
ALTER GROUP userlevel1 DROP USER $1; ALTER GROUP userlevel2 DROP USER $1; ALTER GROUP
userlevel3 DROP USER $1;
ALTER GROUP userlevel4 DROP USER $1; ALTER GROUP userlevel5 DROP USER $1;
CASE $2
WHEN 5 THEN
(ALTER GROUP userlevel5 ADD USER $1)
WHEN 4 THEN
(ALTER GROUP userlevel5 ADD USER $1; ALTER GROUP userlevel4 ADD USER $1;)
[...]
END;
SELECT '';
' LANGUAGE 'SQL';

I don't understand why this function ist refused by postgresql with an parse error at the first $1 as ist every
other method I tryed to get postgres making an "alter group" with a variable. I'd be very happy if someone
could help...

yours

Matthias Nagl

__________________________________________________________________________
Die sicherste Form der Kommunikation: E-Mails verschluesseln, Spam-Filter,
Adressverifizierung, digitale Unterschrift: http://freemail.web.de