题解 | 每个部门薪资排名前两名员工

SELECT department,employee_name,salary
FROM(    
    SELECT department,employee_name,salary,
    RANK() OVER (PARTITION BY department ORDER BY salary DESC) AS rk
    FROM employees
) AS ranked_employees
WHERE rk <= 2
ORDER BY department ASC,salary DESC

此题ez，题目指定用窗口函数解题那就用RANK函数分组排序后选出rk<=2的作为每个部门前二名然后排序输出就好了