586. 订单最多的客户

题目

表:Orders

Column Name	Type
`order_number`	int
customer_number	int

Order_number是该表的主键。此表包含关于订单ID和客户ID的信息。

编写一个SQL查询，为下了最多订单的客户查找 customer_number 。测试用例生成后，恰好有一个客户比任何其他客户下了更多的订单。

查询结果格式如下所示。

示例 1:

输入: Orders 表:

order_number	customer_number
1	1
2	2
3	3
4	3

输出:

customer_number
3

解释: customer_number 为 '3' 的顾客有两个订单，比顾客 '1' 或者 '2' 都要多，因为他们只有一个订单。所以结果是该顾客的 customer_number ，也就是 3 。

进阶：如果有多位顾客订单数并列最多，你能找到他们所有的 customer_number 吗？

题解

sql

SELECT `t`.`customer_number`
FROM (
         SELECT `customer_number`, COUNT(1) AS `cnt` FROM `orders` GROUP BY `customer_number`
     ) `t`
ORDER BY `t`.`cnt` DESC
LIMIT 1

SELECT `t`.`customer_number`
FROM (
         SELECT `customer_number`, COUNT(1) AS `cnt` FROM `orders` GROUP BY `customer_number`
     ) `t`
ORDER BY `t`.`cnt` DESC
LIMIT 1

586. 订单最多的客户 ​

题目 ​

题解 ​

586. 订单最多的客户

题目

题解