Hi Gurus!
I have a table ff, that has 2 columns id_1 and id_2.
with ff as
(
select 1 id_1, 1 id_2 from dual union all
select 2 id_1, null id_2 from dual union all
select 3 id_1, null id_2 from dual union all
select 4 id_1, 2 id_2 from dual union all
select 5 id_1, 3 id_2 from dual union all
select 6 id_1, null id_2 from dual union all
select 7 id_1, 4 id_2 from dual
)select * from ff
ID_1 ID_2
------------
1 1
2
3
4 2
5 3
6
7 4
Desired output:
ID_1 ID_2
------------
1 1
2 1
3 1
4 2
5 3
6 3
7 4
Hope this makes sense
Thanks