SQL中的ANY、SOME、ALL关键字

带any嵌套查询

select emp.empno,emp.ename,emp.sal from scott.emp where sal>any(select sal from scott.emp where job='manager');

等价于

select sal from scott.emp where job='manager' 结果为 sal：2975 2850 2450

select emp.empno,emp.ename,emp.sal from scott.emp where sal>2975 or sal>2850 or sal>2450

带some嵌套查询

select emp.empno,emp.ename,emp.sal from scott.emp where sal=some(select sal from scott.emp where job='manager');

等价于

select sal from scott.emp where job='manager' 结果为 sal：2975 2850 2450

select emp.empno,emp.ename,emp.sal from scott.emp where sal=2975 or sal=2850 or sal=2450

注：any与some是等价的

带all嵌套查询

select emp.empno,emp.ename,emp.sal from scott.emp where sal>all(select sal from scott.emp where job='manager');

等价于

select sal from scott.emp where job='manager' 结果为 sal：2975 2850 2450

select emp.empno,emp.ename,emp.sal from scott.emp where sal>2975 and sal>2850 and sal>2450