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@comcast.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