LeetCode185——部门工资前三高的员工

版权声明：我的GitHub：https://github.com/617076674。真诚求星！ https://blog.csdn.net/qq_41231926/article/details/86589478

我的LeetCode代码仓：https://github.com/617076674/LeetCode

原题链接：https://leetcode-cn.com/problems/department-top-three-salaries/description/

题目描述：

知识点：JOIN连接查询、子查询、DISTINCT关键字

思路：JOIN子句实现两表连接查询，子查询查询薪水排名，DISTINCT去除重复薪水

时间复杂度是O(n ^ 2)，其中n为Employee表中的记录数。

SQL语句：

SELECT 
    t1.Name AS Department, t2.Name AS Employee, t2.Salary AS Salary 
FROM
    Employee AS t2 JOIN Department AS t1 ON t2.DepartmentId = t1.Id
WHERE
    (SELECT 
        COUNT(DISTINCT Salary) 
     FROM 
        Employee AS t3 
     WHERE 
        t3.Salary > t2.Salary AND t3.DepartmentId = t2.DepartmentId) < 3;

LeetCode解题报告：