题解 | 获取所有员工当前的manager
select s2.emp_no ,s1.emp_no as manager from dept_manager as s1 join ( select t1.emp_no,t1.dept_no from dept_emp as t1 left join dept_manager as t2 on t1.emp_no = t2.emp_no) as s2 on s1.dept_no = s2.dept_no where s2.emp_no != s1.emp_no;