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
/* #先查询记录 select count(*) as 'sum' FROM salaries as s left join dept_emp as de on s.emp_no = de.emp_no WHERE dept_no is not NULL GROUP by dept_no */ select depart.dept_no, depart.dept_name, fir.s as 'sum' FROM departments as depart join (select dept_no, count(*) as s FROM salaries as s left join dept_emp as de on s.emp_no = de.emp_no WHERE dept_no is not NULL GROUP by dept_no) as fir on depart.dept_no = fir.dept_no ORDER by dept_no;
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