25、获取员工其当前的薪水比其manager当前薪水还高的相关信息

1、题目描述

获取员工其当前的薪水比其manager当前薪水还高的相关信息，当前表示to_date='9999-01-01',
结果第一列给出员工的emp_no，
第二列给出其manager的manager_no，
第三列给出该员工当前的薪水emp_salary,
第四列给该员工对应的manager当前的薪水manager_salary
CREATE TABLE `dept_emp` (
`emp_no` int(11) NOT NULL,
`dept_no` char(4) NOT NULL,
`from_date` date NOT NULL,
`to_date` date NOT NULL,
PRIMARY KEY (`emp_no`,`dept_no`));
CREATE TABLE `dept_manager` (
`dept_no` char(4) NOT NULL,
`emp_no` int(11) NOT NULL,
`from_date` date NOT NULL,
`to_date` date NOT NULL,
PRIMARY KEY (`emp_no`,`dept_no`));
CREATE TABLE `salaries` (
`emp_no` int(11) NOT NULL,
`salary` int(11) NOT NULL,
`from_date` date NOT NULL,
`to_date` date NOT NULL,
PRIMARY KEY (`emp_no`,`from_date`));

输入描述:

无

输出描述:

emp_no	manager_no	emp_salary	manager_salary
10001	10002	88958	72527
10009	10010	95409	94409

2、代码

select t1.emp_no,t2.emp_no as manager_no,t1.salary as emp_salary,t2.salary as manager_salary
from
(select d.emp_no,d.dept_no,s.salary
from dept_emp d
inner join salaries s on d.emp_no=s.emp_no and d.to_date='9999-01-01' and s.to_date='9999-01-01') t1
inner join
(select m.dept_no,m.emp_no,s.salary
 from dept_manager m
 inner join salaries s on m.emp_no=s.emp_no and m.to_date='9999-01-01' and s.to_date='9999-01-01') t2
on t1.dept_no=t2.dept_no and t1.salary>t2.salary;