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 departments.dept_no, dept_name, count(salaries.salary)
from dept_emp left join departments on dept_emp.dept_no=departments.dept_no
right join salaries on dept_emp.emp_no=salaries.emp_no
group by departments.dept_no
order by departments.dept_no
from dept_emp left join departments on dept_emp.dept_no=departments.dept_no
right join salaries on dept_emp.emp_no=salaries.emp_no
group by departments.dept_no
order by departments.dept_no
