plpgsql howto question

Hi all,

I want to use a plpgsql function that returns the value of a column, depending on the arguments ( the code below does not work, hence the question):

CREATE OR REPLACE FUNCTION getcustomername(text, int4)
RETURNS text AS
'
BEGIN
IF $2 = 1 THEN
SELECT lastname FROM person WHERE objectid = $1;
RETURN lastname;
ELSIF $2 = 2 THEN
SELECT name into name1 from company WHERE objectid = $1;
RETURN name1;
END IF;
END
' LANGUAGE 'plpgsql' VOLATILE;

What is the correct way of doing this?

TIA

Groeten,

Joost Kraaijeveld
Askesis B.V.
Molukkenstraat 14
6524NB Nijmegen
tel: 024-3888063 / 06-51855277
fax: 024-3608416
e-mail: J(dot)Kraaijeveld(at)Askesis(dot)nl
web: www.askesis.nl