이런식도 되지 않을까요??ㅋ
WITH TAB AS ( SELECT 'TEST1' COL1, 'TEST2' COL2, 'Y' COL3 FROM DUAL UNION ALL SELECT 'TEST1' COL1, 'TEST2' COL2, 'Y' COL3 FROM DUAL UNION ALL SELECT 'TEST1' COL1, 'TEST2' COL2, 'N' COL3 FROM DUAL) SELECT COL1, COL2, CASE WHEN SUM(DECODE(COL3, 'N', 1, 0)) > 0 THEN 'N' ELSE 'Y' END COL4 FROM TAB GROUP BY COL1, COL2;