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                        /与MySQL的零距离接触

耶，有没有课后习题可以练练手的？

习题习题

JLv

2016-11-08

源自：与MySQL的零距离接触 4-12

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2 回答

落千殇
2020-05-30

https://leetcode-cn.com/problemset/database/

0 回复有任何疑惑可以回复我~

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慕粉4229793
2016-11-08

-- 表的结构 `goods`
--

CREATE TABLE `goods` (
`gid` int(11) NOT NULL,
`value` int(11) NOT NULL,
`type` varchar(10) NOT NULL,
`goodsname` varchar(10) NOT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

--
-- 转存表中的数据 `goods`
--

INSERT INTO `goods` (`gid`, `value`, `type`, `goodsname`) VALUES
(1, 200, '消耗品', '显隐之尘'),
(2, 2000, '防具', '挑战头巾'),
(3, 2200, '武器', '原力法杖'),
(4, 5500, '防具', '强袭装甲'),
(5, 2600, '武器', '漩涡'),
(6, 53, '小件', '铁树枝干'),
(7, 5000, '法器', '血精石');

-- --------------------------------------------------------

--
-- 表的结构 `user`
--

CREATE TABLE `user` (
`id` int(11) NOT NULL,
`name` varchar(10) NOT NULL,
`money` int(11) NOT NULL,
`gid` int(11) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

--
-- 转存表中的数据 `user`
--

INSERT INTO `user` (`id`, `name`, `money`, `gid`) VALUES
(1, '影魔', 10000, 2),
(2, '巫妖', 8000, 3),
(3, '骷髅王', 20000, 1),
(4, '小娜迦', 30000, 2),
(5, '死亡先知', 15000, 3),
(8, '潮汐猎人', 3000, 2),
(9, '水晶室女', 2000, NULL);

1、请选出哪些商品没有被购买过？？？

2、找出那类商品是本月销量冠军？？？

3、找出销量冠军产品及价格？？？

2 回复有任何疑惑可以回复我~

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慕妹7139135

1. select * from goods where gid not in (select gid from user group by gid having gid is not null); 2. select type from goods where gid=(select gid from (select gid,count(1) as count from user group by gid having gid is not null order by count desc)t limit 1);

2017-01-18 回复有任何疑惑可以回复我~

慕妹7139135

3. select goodsname,value from goods where gid=(select gid from (select gid,count(1) as count from user group by gid having gid is not null order by count desc)t limit 1); 仅供参考，欢迎交流:)

2017-01-18 回复有任何疑惑可以回复我~

最好的坏

DOTA的老司机啊！

2018-09-11 回复有任何疑惑可以回复我~