Met recursieve cte die van boven naar kinderen gaat:
with cte as(
select *, code as ultimate from t where code = under
union all
select t.*, c.ultimate from t
join cte c on c.code = t.under
where t.code <> t.under
)
select * from cte
Voor gegevens:
create table t (code int, name varchar(100), under int)
insert into t values
(1, 'National Sales Manager', 1),
(2, 'regional sales manager', 1),
(3, 'area sales manager', 2),
(4, 'sales manager', 3),
(5, 'a', 5),
(6, 'b', 5),
(7, 'c', 5),
(8, 'd', 7),
(9, 'e', 7),
(10, 'f', 9),
(11, 'g', 9)
het genereert de output:
code name under ultimate
1 National Sales Manager 1 1
5 a 5 5
6 b 5 5
7 c 5 5
8 d 7 5
9 e 7 5
10 f 9 5
11 g 9 5
2 regional sales manager 1 1
3 area sales manager 2 1
4 sales manager 3 1
Fiddle http://sqlfiddle.com/#!6/17c12e/1