Re: [SQL] Looking for information on PostgreSQL Stored Procedures

On Sun, Dec 11, 2005 at 11:38:47AM -0500, Douglas McNaught wrote:
> "Foster, Stephen" <stephenlfoster(at)comcast(dot)net> writes:
>
> > WHILE (--Lost on variable name for end of query; EmptyQueryResponse <>
> > 0? --)
> > BEGIN
> > IF LastName = fname THEN
> > DELETE FROM MailingList WHERE id = id;
> > END IF;
> > LastName := fname;
> > FETCH NEXT FROM NewListCursor INTO fname, id;
> > END;
> > CLOSE NewListCursor;
> > $BODY$
> > LANGUAGE 'sql' VOLATILE;
>
> You can't do any looping or other control structures in an SQL
> function. Use PL/pgSQL instead.

And as I mentioned in my previous post, you can loop through query
results without messing around with an explicit cursor.

CREATE FUNCTION testfunc() RETURNS void AS $$
DECLARE
row record;
BEGIN
FOR row IN SELECT * FROM tablename ORDER BY whatever LOOP
-- do stuff that refers to row.column_name
END LOOP;

RETURN;
END;
$$ LANGUAGE plpgsql;

--
Michael Fuhr