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某网站包含两个表，

Customers

表和

Orders

表。编写一个 SQL 查询，找出所有从不订购任何东西的客户。


Customers

表：

+----+-------+
| Id | Name  |
+----+-------+
| 1  | Joe   |
| 2  | Henry |
| 3  | Sam   |
| 4  | Max   |
+----+-------+


Orders

表：

+----+------------+
| Id | CustomerId |
+----+------------+
| 1  | 3          |
| 2  | 1          |
+----+------------+

例如给定上述表格，你的查询应返回：

+-----------+
| Customers |
+-----------+
| Henry     |
| Max       |
+-----------+

第一种，自己的写法：

select Name as Customers
from Customers
where not Customers.Id in (select CustomerId
                           from Customers, Orders
                           where Customers.Id = Orders.CustomerId)

第二种，评论区的写法：

# Write your MySQL query statement below
select Name as Customers
from Customers
where not Customers.Id in (select CustomerId
                           from Orders)