create type LookUp_Return as (
    id int4,
    dstr varchar,
    num numeric
);
CREATE OR REPLACE FUNCTION get_LookUp_test_1(SOMEPARAM int4) RETURNS setof LookUp_Return AS $$
SELECT  id
                   ,dstr
                   ,num
        FROM someTable
        WHERE id > $ 1 ; 
$$ LANGUAGE sql;

CREATE OR REPLACE FUNCTION get_LookUp_test_2(SOMEPARAM int4) RETURNS setof LookUp_Return AS $$
DECLARE
       rec LookUp_Return
BEGIN
        FOR rec IN SELECT  id
                   ,dstr
                   ,num
        FROM someTable
        WHERE id > SOMEPARAM LOOP
             RETURN NEXT rec;
        END LOOP;
END;
$$ LANGUAGE plpgsql;