diff --git "a/38 \351\273\204\346\255\243\347\204\225/20230308 \347\254\254\344\270\203\346\254\241\344\275\234\344\270\232.md" "b/38 \351\273\204\346\255\243\347\204\225/20230308 \347\254\254\344\270\203\346\254\241\344\275\234\344\270\232.md" new file mode 100644 index 0000000000000000000000000000000000000000..888d9ec8001736be993b7c12a51587e19bfaf656 --- /dev/null +++ "b/38 \351\273\204\346\255\243\347\204\225/20230308 \347\254\254\344\270\203\346\254\241\344\275\234\344\270\232.md" @@ -0,0 +1,113 @@ +## 作业 + +```mysql +create database xiaoshuo charset utf8; +use xiaoshuo; +drop database xiaoshuo; +-- 创建作家信息表author +drop table author; +create table author( +author_id int primary key, +author_name varchar(20) unique, +credits int, +vip_id varchar(20), +foreign key (vip_id) references vip(vip_id) +); +insert into author values(1001,'朱逸群',600,'vip01'); +insert into author values(1002,'范建',8510,'vip04'); +insert into author values(1003,'史珍香',981,'vip02'); +insert into author values(1004,'范统',2364,'vip02'); +insert into author values(1005,'杜子腾',257,'vip01'); +insert into author values(1006,'刘产',678,'vip02'); +insert into author values(1007,'杜琦燕',438,'vip03'); + +-- 创建作家等级信息表VIP +create table vip( +vip_id varchar(20) primary key, +vip_name varchar(20) unique +); +insert into vip values('vip01','青铜作家'); +insert into vip values('vip02','白银作家'); +insert into vip values('vip03','黄金作家'); +insert into vip values('vip04','钻石作家'); + +-- 创建小说作品信息表story +create table story( +story_id int primary key auto_increment, +author_id int, +type_id varchar(20), +story_name varchar(50), +views_number int, +foreign key (author_id) references author(author_id), +foreign key (type_id) references type(type_id) +); +insert into story values(1,1002,'L03','母猪产后护理师的二三事',6541); +insert into story values(2,1005,'L04','拖拉机大战蜘蛛侠',563); +insert into story values(3,1003,'L01','这只小龙虾不正经',8754); +insert into story values(4,1006,'L04','一个爹爹三个娃',36354); +insert into story values(5,1006,'L01','皇上滚开本宫只劫财',3674); +insert into story values(6,1005,'L05','给长城贴瓷砖的小太监',6541); +insert into story values(7,1003,'L03','不科学御兽',1257); +insert into story values(8,1005,'L01','镜面管理局',3216); +insert into story values(9,1004,'L02','关于我成为灭魂师之后',1147); +insert into story values(10,1004,'L05','公子别秀',2078); + +-- 创建小说作品信息表 +create table type( +type_id varchar(20) primary key, +type_name varchar(20) unique +); + +insert into type values('L01','玄幻'); +insert into type values('L02','奇幻'); +insert into type values('L03','武侠'); +insert into type values('L04','仙侠'); +insert into type values('L05','都市'); + +-- 1. 根据前面提供的表结构和表数据,创建数据库并分别创建这张四张表;并插入相关数据。(提醒:外键请注意建表顺序和插入数据的顺序) (30分) +-- +-- 2. 将story 表中的story_name字段类型改成varchar(40) 。(2分) +alter table story modify story_name varchar(40); +desc story; +-- 3. 在author表中增加一个性别字段 字段名:author_sex,类型: char(10),要求默认值为'男'。 (3分) +alter table author add author_sex char(10) default '男'; +select * from author; +-- 4. 将作家编号为1005、1007的作家性别改为'女' 。(2分) +update author set author_sex='女' where author_id in(1005,1007); +-- 5. 作家杜子腾,写了一篇名为《拜登夸我很帅》的都市小说,有854个浏览量,请将这条信息插入到story表。(3分) +insert into story values (null,(select author_id from author where author_name='杜子腾'),(select type_id from type where type_name='都市'),'拜登夸我很帅',845); +-- 6. 《拖拉机大战蜘蛛侠》这篇小说,浏览量涨了100,请更新story表中的相关数据。(2分) +update story set views_number=views_number+100 where story_name='拖拉机大战蜘蛛侠'; +-- 7. 请删除story表的中《皇上滚开本宫只劫财》这篇小说相关数据。(2分) +delete from story where story_name='皇上滚开本宫只劫财'; +-- 8. 查询 浏览量大于 8000的小说的作者编号和小说作品名称。(2分) +select author_id,story_name from story where views_number>8000; +-- 9. 查询积分大于1000 并且会员等级高于vip03的作家所有信息。(3分) +select * from author where credits>1000 and vip_id > 'vip03'; +-- 10. 查询姓名以杜字开头的作家的姓名,积分和等级编号。(3分) +select author_name,credits,vip_id from author where author_name like '杜%'; +-- 11. 查询积分在100、1000之间的作家信息,以积分降序排列。 (3分) +select * from author where credits between 100 and 1000 order by credits desc; +-- 12. 查询出小说的总浏览量,最高浏览量,最小浏览量,平均浏览量,给字段用上中文别名(3分) +select sum(views_number) 总浏览量, max(views_number) 最高浏览量, min(views_number) 最小浏览量, avg(views_number) 平均浏览量 from story; +-- 13. 查询各种等级的作家的平均积分和作家数量,并对查询结果使用中文别名。(3分) +select vip_id 等级,avg(credits) 平均积分,count(author_id) 作家数量 from author group by vip_id; +-- 14. 查询小说数量大于等于2的分类编号和小说数量。(4分) +select a.type_id,count(a.type_id) from type a left join story b on a.type_id = b.type_id group by a.type_id having count(a.type_id)>=2; +-- 15. 查询所有小说中浏览量最少的书的作品编号、作品名称和类型编号、浏览量。(4分) +select story_id,story_name,type_id,views_number from story where views_number=(select min(views_number) from story); +-- 16. 查询积分比刘产高的作者所有信息。(5分) +select * from author where credits>(select credits from author where author_name='刘产'); +-- 17. 查询出哪些白银作家是没有写小说的,显示这些作家的姓名、等级名称。(8分) +select a.author_name,a.vip_id from author a left join story b on a.author_id = b.author_id where story_name is null and vip_id=(select vip_id from vip where vip_name='白银作家'); +-- 18. 找出写过作品浏览量大于5000的作家的所有作品中浏览量不到1000的作品信息(8分) +select a.* from story a,(select author_id from story where views_number>5000) b where a.author_id=b.author_id and views_number<1000; +-- 19.查询所有小说的小说编号、小说名称、浏览量、分类名称、作者姓名、作者积分、作者等级名称,结果字段要用中文别名,并按浏览量降序排列,如果浏览量一样的,再按积分降序排列。(10分) + select a.story_id 小说编号,a.story_name 小说名称,a.views_number 浏览量,d.type_name 分类名称,b.author_name 作者姓名,b.credits 作者积点,c.vip_name 作者等级名称 + from + story a left join author b on a.author_id = b.author_id + left join vip c on b.vip_id = c.vip_id + left join type d on a.type_id = d.type_id + order by views_number desc ,credits desc; +``` +