关于Oracle数据库删除、查询(三)

select a1.ename,a1.sal,a2.grade from emp a1,salgrade a2 where a1.sal
between a2.losal and a2.hisal;



select worker.ename,boss.ename from emp worker,emp boss where worker.mgr=boss.empno and worker.mgr='FOLD';





select * from emp where deptno=(select deptno  from emp where ename='SMITH');



select * from emp where job in(select distinct job from emp where deptno=10);



 select ename,sal,deptno from emp where sal>all(select sal from emp where deptno=30);

别的写法：

select ename,sal,deptno from emp where sal>(select
max(sal) from emp where deptno=30);





select * from emp where (deptno,job)=(select  septno,job from emp where ename='SMITH');(标红两处顺序要一致)