오라클이시면 피벗으로 될것 같은데.. 자주 안써서 그런지 쓸데마다 헷갈리네요..^^;
with t (group_id, member_id, member_class) as ( select 1, 4, 'A' from dual union all select 1, 5, 'B' from dual union all select 1, 6, 'C' from dual union all select 2, 7, 'A' from dual union all select 2, 8, 'B' from dual union all select 2, 9, 'C' from dual ) select * from t pivot (min(member_id) for member_class in ('A' as A_id ,'B' as B_id,'C' as C_id))