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by Sumit Chourasia | Oct 16, 2020 | Category :coding | Tags : algorithm data-structure easy leetcode mysql sql

Customers Who Never Order - Sql - Easy - LeetCode

Customers Who Never Order - Sql - Easy - LeetCode

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       |
+-----------+

# Write your MySQL query statement below
Select Name as Customers from Customers Where Id Not In(select CustomerId from Orders);