/*第一步：筛选出员工的no和salary a */ 
select s.emp_no,s.salary emp_salary,de.dept_no
from salaries s left join dept_emp de on s.emp_no=de.emp_no
/*第二步：筛选出经理的的no和salary b */
select dm.emp_no manager_no,s.salary manager_salary,dm.dept_no
from dept_manager dm left join salaries s on dm.emp_no=s.emp_no

完整的代码

select a.emp_no,b.manager_no,a.emp_salary,b.manager_salary
from 
(select s.emp_no,s.salary emp_salary,de.dept_no
from salaries s left join dept_emp de on s.emp_no=de.emp_no
) a
inner join 
(select dm.emp_no manager_no,s.salary manager_salary,dm.dept_no
from dept_manager dm left join salaries s on dm.emp_no=s.emp_no
)b
on a.dept_no=b.dept_no
where a.emp_salary > b.manager_salary