题解 | 获取员工其当前的薪水比其manager当前薪水还高的相关信息

select
es.emp_no, ms.manager_no, es.salary, ms.salary
from
(SELECT dm.emp_no manager_no, s.salary salary, dm.dept_no dept_no
FROM dept_manager dm left join salaries s on dm.emp_no = s.emp_no 
where s.to_date = '9999-01-01' ) ms right join
(select de.emp_no emp_no, s.salary salary, de.dept_no dept_no
from dept_emp de left join salaries s on de.emp_no = s.emp_no
where s.to_date = '9999-01-01' ) es on ms.dept_no = es.dept_no 
where es.salary > ms.salary