183. Customers Who Never Order

Easy

Problem Description

183. Customers Who Never Order

Easy


Table: Customers

+-------------+---------+
| Column Name | Type    |
+-------------+---------+
| id          | int     |
| name        | varchar |
+-------------+---------+
id is the primary key (column with unique values) for this table.
Each row of this table indicates the ID and name of a customer.

 

Table: Orders

+-------------+------+
| Column Name | Type |
+-------------+------+
| id          | int  |
| customerId  | int  |
+-------------+------+
id is the primary key (column with unique values) for this table.
customerId is a foreign key (reference columns) of the ID from the Customers table.
Each row of this table indicates the ID of an order and the ID of the customer who ordered it.

 

Write a solution to find all customers who never order anything.

Return the result table in any order.

The result format is in the following example.

 

Example 1:

Input: 
Customers table:
+----+-------+
| id | name  |
+----+-------+
| 1  | Joe   |
| 2  | Henry |
| 3  | Sam   |
| 4  | Max   |
+----+-------+
Orders table:
+----+------------+
| id | customerId |
+----+------------+
| 1  | 3          |
| 2  | 1          |
+----+------------+
Output: 
+-----------+
| Customers |
+-----------+
| Henry     |
| Max       |
+-----------+

Solution

0183-customers-who-never-order.sql

sql
0183-customers-who-never-order.sql
1# Write your MySQL query statement below 2select name as Customers from Customers where id not in (SELECT customerId FROM Orders);