获取员工其当前的薪水比其manager当前薪水还高的相关信息

with t1 as(
    select dept_emp.emp_no,
        dept_manager.emp_no as manager_no,
        salary as emp_salary
    from dept_emp
    left join salaries using(emp_no)
    left join dept_manager using(dept_no)
    where dept_emp.emp_no not in (select emp_no from dept_manager)
),
t2 as(
    select t1.*,
        salary as manager_salary
    from t1
    left join salaries on(manager_no=salaries.emp_no)
)

select * from t2
where emp_salary>manager_salary

dept_emp(emp_no)、dept_manager(dept_no)、salaries（emp_no）、salaries(manager_no) 四表连接