Splitting Comma Separated string into columns by using REGEXP_SUBSTR
select
  regexp_substr(pq, '[^,]+', 1, 1) as po,
  regexp_substr(pq, '[^,]+', 1, 2) as qty
from
(
  select
    regexp_substr('po1,qty1,po2,qty2','[^,]+,[^,]+', 1, level) as pq
  from dual
    connect by regexp_substr('po1,qty1,po2,qty2','[^,]+,[^,]+', 1, level) is not null
);


PO         QTY
---------- ----------
po1        qty1
po2        qty2