题解 | #获取所有非manager的员工emp_no#
获取所有非manager的员工emp_no
http://www.nowcoder.com/practice/32c53d06443346f4a2f2ca733c19660c
考点：left join/is null
- 首先筛选出不是manager的员工
- 然后选取这些员工的id
select emp_no from (select *
from employees e
left join dept_manager d
on e.emp_no = d.emp_no
where d.dept_no is null)
