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 | +-----------+
Suppose that a website contains two tables, the Customers table and the Orders table. Write a SQL query to find all customers who never order anything.
select Name as `Customers`
from Customers
where Id not in (select CustomerId from Orders)