oracle數據庫。查詢部門平均工資，平且顯示工資等級，按部門分組，sql語句怎麽寫

如果是scott下的那幾張表的話

select?t1.deptno,

t1.dname,

t1.avgsal,

max(case

when?t1.avgsal?between?t2.losal?and?t2.hisal?then

t2.grade

end)?grade

from?(select?a.deptno,?b.dname,?round(avg(a.sal),?2)?avgsal

from?emp?a,?dept?b

where?a.deptno?=?b.deptno

group?by?a.deptno,?b.dname)?t1,

salgrade?t2

group?by?t1.deptno,?t1.dname,?t1.avgsal

order?by?t1.deptno;

查詢結果