LeetCode Customers Who Never Order，leetcodecustomers

LeetCode Customers Who Never Order，leetcodecustomers

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.

Table: Customers.

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

Table: Orders.

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

Using the above tables as example, return the following:

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

原來表名是要區分大小寫。

select name from Customers where id not in (select customerid from Orders)