with t as
(
select '1' no_seq, 'a' da  from dual union all
select '1' no_seq, 'b' da  from dual union all
select '2' no_seq, 'a' da  from dual union all
select '3' no_seq, 'a' da  from dual union all
select '3' no_seq, 'b' da  from dual union all
select '4' no_seq, 'a' da  from dual union all
select '5' no_seq, 'a' da  from dual union all
select '5' no_seq, 'b' da  from dual union all
select '6' no_seq, 'b' da  from dual 
)
select
no_seq, da
from t
WHERE no_seq <= '5' 

--OR (no_seq = '5' AND da <> 'b') ?

5이하의 숫자만 가져오는데

이때 숫자가 5이면서 b는 제거하고 나머지만 가지고오고싶어요!