题解 | 获取每个部门中薪水最高的员工相关信息
SELECT dept_no,emp_no,salary
FROM(
SELECT b.dept_no,a.emp_no,a.salary,RANK() OVER(partition by b.dept_no order by a.salary DESC) s_rank
FROM salaries a
LEFT JOIN dept_emp b
ON a.emp_no = b.emp_no) AS a
WHERE s_rank = 1
ORDER BY dept_no