183. Customers Who Never Order

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SQL Schema Discuss Pick One
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 |
+———–+

Answer:

SELECT c.Name AS Customers FROM Customers cWHERE c.Id NOT IN (SELECT CustomerId FROM Orders)SELECT c.Name Customers FROM Customers c LEFT JOIN Orders oON c.Id = o.CustomerId WHERE o.CustomerId IS NULL