求部門中哪些人的薪水最高
以下是代碼片段：select ename,sal from emp join (select max(sal) max_sal, deptno from emp group by deptno) t on (emp.sal = t.max_sal and emp.deptno = t.deptno); -
求部門平均薪水的等級
以下是代碼片段：select deptno,avg_sal,grade from (select deptno,avg(sal) avg_sal from emp group by deptno) t join salgrade s on (t.avg_sal between s.losal and s.hisal);
求部門平均的薪水等級
以下是代碼片段：select deptno,avg(grade) from (select deptno,ename,grade from emp join salgrade s on (emp.sal between s.losal and s.hisal)) t group by deptno;
雇員中哪些人是經理人
以下是代碼片段：select ename from emp where empno in (select distinct mgr from emp);
不用組函數，求薪水的最高值
以下是代碼片段：select sal from emp where sal not in (select distinct e1.sal from emp e1 join emp e2 on (e1.sal < e2.sal))
用組函數，求薪水的最高值
以下是代碼片段：
select max(sal) from emp；
求平均薪水最高的部門的部門編號
以下是代碼片段：select deptno , avg_sal from (select avg(sal) avg_sal,deptno from emp group by deptno) t where avg_sal = (select max(avg_sal) from (select avg(sal) avg_sal,deptno from emp group by deptno) t)；
組函數嵌套的寫法
以下是代碼片段：select deptno , avg_sal from (select avg(sal) avg_sal,deptno from emp group by deptno) t where avg_sal = (select max(avg(sal)) from emp group by deptno)；
求平均薪水最高的部門的名稱
以下是代碼片段：select dname from dept where deptno = ( select deptno from (select avg(sal) avg_sal,deptno from emp group by deptno) t where avg_sal = (select max(avg_sal) from (select avg(sal) avg_sal,deptno from emp group by deptno) t) )；
求平均薪水的等級最低的部門的部門名稱
以下是代碼片段：select avg(sal) avg_sal,deptno from emp group by deptno
部門平均薪水
以下是代碼片段：select min(avg_sal) from ( select avg(sal) avg_sal,deptno from emp group by deptno )
平均工資的最小值
以下是代碼片段：select avg_sal,deptno from (select avg(sal) avg_sal,deptno from emp group by deptno) t where avg_sal = ( select min(avg_sal) from ( select avg(sal) avg_sal,deptno from emp group by deptno ) )
平均工資的最小值及部門編號
以下是代碼片段：select t.avg_sal,t.deptno,s.grade from (select avg(sal) avg_sal,deptno from emp group by deptno) t join salgrade s on (t.avg_sal between s.losal and s.hisal) where avg_sal = ( select min(avg_sal) from ( select avg(sal) avg_sal,deptno from emp group by deptno ) )
平均工資的最小值及部門編號和工資等級
以下是代碼片段：select d.dname,t.avg_sal,t.deptno,s.grade from (select avg(sal) avg_sal,deptno from emp group by deptno) t join salgrade s on (t.avg_sal between s.losal and s.hisal) join dept d on (t.deptno = d.deptno) where avg_sal = ( select min(avg_sal) from ( select avg(sal) avg_sal,deptno from emp group by deptno ) )
平均工資的最小值及部門編號和工資等級及部門名稱
Another 按照題意的寫法
以下是代碼片段：select t1.deptno,t1.avg_sal,grade,d.dname from ( select deptno,avg_sal,grade from (select deptno,avg(sal) avg_sal from emp group by deptno) t join salgrade s on (t.avg_sal between s.losal and s.hisal) ) t1 join dept d on (t1.deptno = d.deptno) where grade = ( select min(grade) from ( select deptno,avg_sal,grade from (select deptno,avg(sal) avg_sal from emp group by deptno) t join salgrade s on (t.avg_sal between s.losal and s.hisal) ) );
創建視圖或者表，如果沒有權限
以下是代碼片段：conn sys/sys as sysdba;
已連接。
以下是代碼片段：grant create table, create vIEw to scott;
本文就為大家介紹這麼多，這只是其中的一小部分，還有很多這裡沒有介紹到，以後還會繼續為大家介紹更多的知識，希望能夠幫助到大家。
