题目信息

表: Employee

+-------------+---------+
| Column Name | Type    |
+-------------+---------+
| id          | int     |
| name        | varchar |
| department  | varchar |
| managerId   | int     |
+-------------+---------+
id 是此表的主键（具有唯一值的列）。
该表的每一行表示雇员的名字、他们的部门和他们的经理的id。
如果managerId为空，则该员工没有经理。
没有员工会成为自己的管理者。

编写一个解决方案，找出至少有五个直接下属的经理。

以 任意顺序 返回结果表。

查询结果格式如下所示。

示例 ：

输入: 
Employee 表:
+-----+-------+------------+-----------+
| id  | name  | department | managerId |
+-----+-------+------------+-----------+
| 101 | John  | A          | Null      |
| 102 | Dan   | A          | 101       |
| 103 | James | A          | 101       |
| 104 | Amy   | A          | 101       |
| 105 | Anne  | A          | 101       |
| 106 | Ron   | B          | 101       |
+-----+-------+------------+-----------+
输出: 
+------+
| name |
+------+
| John |
+------+

题解：

sql">SELECT Employee.Name as Name
FROM (SELECT ManagerId as IdFROM EmployeeGROUP BY ManagerIdHAVING COUNT(Id)>=5
) as Manager 
JOIN Employee
ON Manager.Id=Employee.Id

sql">SELECT Manager.Name as Name
FROM
Employee AS Manager JOIN Employee AS Report
ON Manager.Id = Report.ManagerId
GROUP BY Manager.Id
HAVING COUNT(Report.Id) >= 5