Oracle 21c

By using db<>fiddle, you agree to license everything you submit by Creative Commons CC0.

create table your_table (ID, A_ID, B_ID, C_ID, D_ID) as
select 1, 'ABC', 'XYZ', 'PLO', 'QWE' from dual
1 rows affected

select *
from your_table
unpivot (a_id for orig_id in (a_id, b_id, c_id, d_id))


ID
ORIG_ID
A_ID


1
A_ID
ABC

1
B_ID
XYZ

1
C_ID
PLO

1
D_ID
QWE


select id, a_id
from your_table
unpivot (a_id for orig_id in (a_id, b_id, c_id, d_id))


ID
A_ID


1
ABC

1
XYZ

1
PLO

1
QWE