题解 | #统计各个部门的工资记录数#
统计各个部门的工资记录数
https://www.nowcoder.com/practice/6a62b6c0a7324350a6d9959fa7c21db3
select dt.dept_no,dept_name,count(*) as 'sum' from departments dt join dept_emp dp using(dept_no) join salaries s using(emp_no) group by dt.dept_no order by dept_no
