题解 | #汇总各个部门当前员工的title类型的分配数目#
汇总各个部门当前员工的title类型的分配数目
https://www.nowcoder.com/practice/4bcb6a7d3e39423291d2f7bdbbff87f8
select
d.dept_no,d.dept_name,t.title,count(*) as count
from departments d
join dept_emp de
on d.dept_no = de.dept_no
join titles t
on de.emp_no = t.emp_no
group by d.dept_no, d.dept_name, t.title
order by d.dept_no,t.title;
- ‘汇总’、‘各自各个’之类,通常会用到
group by
进行分组