crose join을 사용하면 됩니다.

select COL_A, COL_B, COL_C, COL_D, COL_E from
(select COL_A from T where COL_A is not null),
(select COL_B from T where COL_B is not null),
(select COL_C from T where COL_C is not null),
(select COL_D from T where COL_D is not null),
(select COL_E from T where COL_E is not null)
order by 1, 2, 3, 4, 5

빠른 답변 감사드립니다 좀 응용은 해야 되겠지만 시원한 답이 되었습니다

WITH T AS
(
SELECT 'A1' COL_A , NULL COL_B, NULL COL_C, NULL COL_D , NULL COL_E FROM DUAL UNION ALL
SELECT NULL , 'B1' , NULL , NULL , NULL FROM DUAL UNION ALL
SELECT NULL , NULL , 'C1' , NULL , NULL FROM DUAL UNION ALL
SELECT NULL , NULL , 'C2' , NULL , NULL FROM DUAL UNION ALL
SELECT NULL , NULL , NULL , NULL , 'E1' FROM DUAL UNION ALL
SELECT NULL , NULL , NULL , NULL , 'E2' FROM DUAL UNION ALL
SELECT NULL , NULL , NULL , NULL , 'E3' FROM DUAL UNION ALL
SELECT NULL , NULL , NULL , NULL , 'E4' FROM DUAL UNION ALL
SELECT NULL , NULL , NULL , 'D1' , NULL FROM DUAL UNION ALL
SELECT NULL , NULL , NULL , 'D2' , NULL FROM DUAL UNION ALL
SELECT NULL , NULL , NULL , 'D3' , NULL FROM DUAL
)
, t1 AS
(
SELECT COALESCE(col_a, col_b, col_c, col_d, col_e) col
, CASE WHEN col_a IS NOT NULL THEN 1
WHEN col_b IS NOT NULL THEN 2
WHEN col_c IS NOT NULL THEN 3
WHEN col_d IS NOT NULL THEN 4
WHEN col_e IS NOT NULL THEN 5
END lv
FROM t
)
SELECT SYS_CONNECT_BY_PATH(col, ',')
FROM t1
WHERE lv = 5
START WITH lv = 1
CONNECT BY PRIOR lv + 1 = lv
;

우~~마농님..올만입니다.
역시 COALESCE 를 이런곳에서도 사용하는군요..
원했던 건 칼럼이었는데..유용하게 참고하겠습니다.
수고하세요..