SQL> select * from emp;
EMP_ID DEPT_ID EMP_NAME SALARY ------ ------ ---------- ---------- E01 D01 なまえ1 150 E02 D02 なまえ2 200 E03 D03 なまえ3 300 E04 D02 なまえ4 400 E05 D03 なまえ5 500
SQL> select 2 max( salary ) 3 from emp;
MAX(SALARY) ----------- 500
SQL> select 2 max( salary ) 3 from emp 4 group by dept_id;
MAX(SALARY) ----------- 150 400 500
SQL> select 2 max( salary ) 3 from emp 4 group by dept_id 5 having max( salary ) > 300;
MAX(SALARY) ----------- 400 500