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
http://www.nowcoder.com/practice/6a62b6c0a7324350a6d9959fa7c21db3
select d.dept_no,d.dept_name,count(s.salary) AS SUM from departments d left join dept_emp de on d.dept_no=de.dept_no left join salaries s on de.emp_no=s.emp_no GROUP BY d.dept_no ORDER BY d.dept_no ASC;