Leetcode: Customers Who Never Order

Customers Who Never Order



Similar Problems:


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

Github: code.dennyzhang.com

Credits To: leetcode.com

Leave me comments, if you have better ways to solve.


## Blog link: https://code.dennyzhang.com/customers-who-never-order
select Customers.Name as Customers
from Customers left join Orders on Customers.Id = Orders.CustomerId
where Orders.CustomerId is Null;
linkedin
github
slack

Share It, If You Like It.

Leave a Reply

Your email address will not be published.