Strange bahaviour

I just got the following example:

DROP TABLE foo;
CREATE TABLE foo (login varchar(100));
INSERT INTO foo values ('abc');

DROP FUNCTION footest1(varchar(100));
CREATE FUNCTION footest1(varchar(100)) RETURNS varchar(100) AS '
DECLARE
login varchar(100);
BEGIN
SELECT INTO login login FROM foo LIMIT 1;
RETURN login;
END;
' LANGUAGE 'plpgsql';

DROP FUNCTION footest2(varchar(100));
CREATE FUNCTION footest2(varchar(100)) RETURNS varchar(100) AS '
DECLARE
fieldname varchar(100);
BEGIN
SELECT INTO fieldname login FROM foo LIMIT 1;
RETURN fieldname;
END;
' LANGUAGE 'plpgsql';

SELECT footest1('foobar');
SELECT footest2('foobar');

The first select returns NULL while the second correctly returns 'abc'.
I just wonder why it is that way. The only difference seems to be the
name of the variable which in footest1 equals the attribute name.

Now I can guess what happens but I wonder if this is the desired
behaviour.

Michael
--
Michael Meskes
Michael(at)Fam-Meskes(dot)De
Go SF 49ers! Go Rhein Fire!
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