题目介绍: 购买了产品A和产品B却没有购买产品C的顾客 customers-who-bought-products-a-and-b-but-not-c
难度中等
SQL架构
Customers
表:
+---------------------+---------+
| Column Name | Type |
+---------------------+---------+
| customer_id | int |
| customer_name | varchar |
+---------------------+---------+
customer_id 是这张表的主键。
customer_name 是顾客的名称。
Orders
表:
+---------------+---------+
| Column Name | Type |
+---------------+---------+
| order_id | int |
| customer_id | int |
| product_name | varchar |
+---------------+---------+
order_id 是这张表的主键。
customer_id 是购买了名为 "product_name" 产品顾客的id。
请你设计 SQL 查询来报告购买了产品 A 和产品 B 却没有购买产品 C 的顾客的 ID 和姓名(
customer_id
和
customer_name
),我们将基于此结果为他们推荐产品 C 。 您返回的查询结果需要按照
customer_id
排序。
查询结果如下例所示。
``` Customers table: +-------------+---------------+ | customer_id | customer_name | +-------------+---------------+ | 1 | Daniel | | 2 | Diana | | 3 | Elizabeth | | 4 | Jhon | +-------------+---------------+
Orders table: +------------+--------------+---------------+ | order_id | customer_id | product_name | +------------+--------------+---------------+ | 10 | 1 | A | | 20 | 1 | B | | 30 | 1 | D | | 40 | 1 | C | | 50 | 2 | A | | 60 | 3 | A | | 70 | 3 | B | | 80 | 3 | D | | 90 | 4 | C | +------------+--------------+---------------+
Result table: +-------------+---------------+ | customer_id | customer_name | +-------------+---------------+ | 3 | Elizabeth | +-------------+---------------+ 只有 customer_id 为 3 的顾客购买了产品 A 和产品 B ,却没有购买产品 C 。 ```
sql
select o.customer_id, customer_name
from Orders o left join Customers c
on o.customer_id=c.customer_id
group by customer_id
having sum(product_name ='A')>=1 and sum(product_name='B')>=1 and sum(product_name='C')=0