183. Customers Who Never Order (Easy)

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 |
+-----------+

---

Solution

inspired by the official solution

SELECT Customers.Name AS Customers
FROM Customers
WHERE Customers.Id NOT IN (
    SELECT Orders.CustomerId
    FROM Orders
    )
;