1 Create table If Not Exists Employee (Id int, Name varchar(255), Salary int, ManagerId int)
2 Truncate table Employee
3 insert into Employee (Id, Name, Salary, ManagerId) values ('1', 'Joe', '70000', '3')
4 insert into Employee (Id, Name, Salary, ManagerId) values ('2', 'Henry', '80000', '
 
4')
5 insert into Employee (Id, Name, Salary, ManagerId) values ('3', 'Sam', '60000', 'None')
6 insert into Employee (Id, Name, Salary, ManagerId) values ('4', 'Max', '90000', 'None')

The Employee table holds all employees including their managers. Every employee has an Id, and there is also a column for the manager Id.

+----+-------+--------+-----------+
| Id | Name  | Salary | ManagerId |
+----+-------+--------+-----------+
| 1  | Joe   | 70000  | 3         |
| 2  | Henry | 80000  | 4         |
| 3  | Sam   | 60000  | NULL      |
| 4  | Max   | 90000  | NULL      |
+----+-------+--------+-----------+

Given the Employee

+----------+
| Employee |
+----------+
| Joe      |
+----------+

+----+-------+--------+-----------+
| Id | Name  | Salary | ManagerId |
+----+-------+--------+-----------+
| 1  | Joe   | 70000  | 3         |
| 2  | Henry | 80000  | 4         |
| 3  | Sam   | 60000  | NULL      |
| 4  | Max   | 90000  | NULL      |
+----+-------+--------+-----------+

給定 Employee 表，編寫一個 SQL 查詢，該查詢可以獲取收入超過他們經理的員工的姓名。在上面的表格中，Joe 是唯一一個收入超過他的經理的員工。

+----------+
| Employee |
+----------+
| Joe      |
+----------+

182ms

 1 # Write your MySQL query statement below
 2 select E1.Name as Employee 
 3         from(
 4             select * from Employee
 5         )E1
 6         left join 
 7         (
 8             select * from Employee
 9                 group by id
10         )E2
11         on E1.ManagerId = E2.Id
12         where E1.Salary > E2.Salary

185ms

1 SELECT b.Name AS Employee
2 FROM Employee a
3 JOIN Employee b
4 ON a.ID = b.ManagerID
5 WHERE b.Salary > a.Salary;

647ms

1 /* Write your T-SQL query statement below */
2 SELECT a.Name AS Employee
3 FROM Employee a
4     JOIN Employee b ON a.ManagerId = b.Id
5 WHERE a.Salary > b.Salary