[LeetCode]#183. Customers Who Never Order

Environment: MySQL

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:

# Write your MySQL query statement belowselect customers.name as 'Customers'
from customers
where customers.id not in
(
select customerid from orders
);

Submitted result:

Reference:

https://leetcode.com/problems/customers-who-never-order/solution/

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