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leetcode183. 從不訂購的客戶

某網站包含兩個表,Customers 表和 Orders 表。編寫一個 SQL 查詢,找出所有從不訂購任何東西的客戶。

Customers 表:

±—±------+
| Id | Name |
±—±------+
| 1 | Joe |
| 2 | Henry |
| 3 | Sam |
| 4 | Max |
±—±------+
Orders 表:

±—±-----------+
| Id | CustomerId |
±—±-----------+
| 1 | 3 |
| 2 | 1 |
±—±-----------+
例如給定上述表格,你的查詢應返回:

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

SELECT
Customers.NAME AS Customers
FROM
Customers
left JOIN Orders ON Orders.CustomerId = Customers.id
where Orders.id is null