子查询

 

 大于30号部门最高工资的所有员工信息（2种写法）

select * from emp where sal>all(select sal from emp e2 where deptno=30)

select * from emp e where sal>(select max(sal) from emp e2 where deptno=30)

 

 

select * from emp e where (job,sal) = (select job,sal from emp where ename='ALLEn')

select * from emp e where job=(select job from emp where ename='ALLEn') and sal=(select sal from emp where ename='ALLEn')