select e.empno, e.ename, e.sal, d.avgsal
from emp e, (select deptno, avg(sal) avgsal from emp group by deptno) d
where e.deptno = d.deptno
and e.sal > d.avgsal ;sql
執行結果oracle
select empno,
ename,
sal,
(select avg(sal) from emp where deptno = e.deptno) avgsal
from emp e
where sal > (select avg(sal) from emp where deptno = e.deptno)spa
explain plan for #解釋執行計劃3d
執行計劃 #sql語句塊,即你查詢的sql語句複製粘貼到這裏便可 blog
select * from table(dbms_xplan.display); #查詢執行計劃table
explain plan for #解釋執行計劃
select e.empno, e.ename, e.sal, d.avgsal
from emp e, (select deptno, avg(sal) avgsal from emp group by deptno) d #sql語句
where e.deptno = d.deptno
and e.sal > d.avgsal ;
select * from table(dbms_xplan.display); #查詢執行計劃模板
返回結果:select
explain plan for #解釋執行計劃
select empno,
ename,
sal,
(select avg(sal) from emp where deptno = e.deptno) avgsal #sql語句
from emp e
where sal > (select avg(sal) from emp where deptno = e.deptno);
select * from table(dbms_xplan.display); #查詢執行計劃表sql語句
返回結果:im
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