2022-12-01:从不订购的客户。找出所有从不订购任何东西的客户,以下数据的答案输出是Henry和Max,sql语句如何写? DROP TABLE IF EXISTS `customers`; C

2022-12-01:从不订购的客户。找出所有从不订购任何东西的客户,以下数据的答案输出是Henry和Max,sql语句如何写?

DROP TABLE IF EXISTS `customers`;
CREATE TABLE `customers` (
  `id` int(11) NOT NULL,
  `name` varchar(255) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

INSERT INTO `customers` VALUES ('1', 'Joe');
INSERT INTO `customers` VALUES ('2', 'Henry');
INSERT INTO `customers` VALUES ('3', 'Sam');
INSERT INTO `customers` VALUES ('4', 'Max');

DROP TABLE IF EXISTS `orders`;
CREATE TABLE `orders` (
  `id` int(11) NOT NULL,
  `customer_id` int(11) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

INSERT INTO `orders` VALUES ('1', '3');
INSERT INTO `orders` VALUES ('2', '1');

答案2022-12-01:

sql语句如下:

select customers.name 
from customers
where customers.id not in
(
    select customer_id from orders
);

运行结果如下:
在这里插入图片描述

posted @ 2022-12-01 20:44  福大大架构师每日一题  阅读(8)  评论(0编辑  收藏  举报  来源