lc-184


表: Employee

+--------------+---------+
| 列名          | 类型    |
+--------------+---------+
| id           | int     |
| name         | varchar |
| salary       | int     |
| departmentId | int     |
+--------------+---------+
在 SQL 中,id是此表的主键。
departmentId 是 Department 表中 id 的外键(在 Pandas 中称为 join key)。
此表的每一行都表示员工的 id、姓名和工资。它还包含他们所在部门的 id。

表: Department

+-------------+---------+
| 列名         | 类型    |
+-------------+---------+
| id          | int     |
| name        | varchar |
+-------------+---------+
在 SQL 中,id 是此表的主键列。
此表的每一行都表示一个部门的 id 及其名称。

查找出每个部门中薪资最高的员工。
任意顺序 返回结果表。
查询结果格式如下例所示。

示例 1:

输入:
Employee 表:
+----+-------+--------+--------------+
| id | name  | salary | departmentId |
+----+-------+--------+--------------+
| 1  | Joe   | 70000  | 1            |
| 2  | Jim   | 90000  | 1            |
| 3  | Henry | 80000  | 2            |
| 4  | Sam   | 60000  | 2            |
| 5  | Max   | 90000  | 1            |
+----+-------+--------+--------------+
Department 表:
+----+-------+
| id | name  |
+----+-------+
| 1  | IT    |
| 2  | Sales |
+----+-------+
输出:
+------------+----------+--------+
| Department | Employee | Salary |
+------------+----------+--------+
| IT         | Jim      | 90000  |
| Sales      | Henry    | 80000  |
| IT         | Max      | 90000  |
+------------+----------+--------+
解释:Max 和 Jim 在 IT 部门的工资都是最高的,Henry 在销售部的工资最高。
# Write your MySQL query statement below
select Department.name as Department, Employee.name as Employee, Employee.salary as Salary from Employee inner join (select departmentId,max(salary) salary from Employee group by departmentId) aa on Employee.departmentId = aa.departmentId and Employee.salary = aa.salary inner join Department on Employee.departmentId = Department.id

文章作者: 倪春恩
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