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 de.dept_no,d.dept_name, count(de.dept_no) sum from dept_emp de inner join salaries s on de.emp_no=s.emp_no inner join departments d on de.dept_no=d.dept_no group by de.dept_no order by de.dept_no
连接三个表,使用inner join