mysql 创建学生表、课程表、学生选课表

数据库系统概论(第五版)79页提供的三个表，为了我们上机操作容易，下面创建这三个表

学生–课程数据库中包含以下三个表

• 学生表：Student(Sno,Sname,Ssex,Sage,Sdept)
• 课程表：Course(Cno,Cname,Cpno,Ccredit)
• 学生选课表：SC(Sno,Cno,Grade)

关系的主码加粗表示，各个表中的数据实例：

Student

Course

SC

1、建表语句

Sno为Student表的主键，Cno为Course表的主键，SC表中外键Sno，Cno分别是Student表和Course表的主键

create table Student (Sno char(9) primary key,Sname char(20),Ssex char(2),Sage int,Sdept char(10))charset=utf8;

create table Course (Cno char(2) primary key,Cname char(20),Cpno char(2),Ccredit integer)charset=utf8;

create table SC (Sno char(9),Cno char(2),Grade float,foreign key(Sno) references Student(Sno),foreign key(Cno) references Course(Cno))charset=utf8;

2、插入数据

insert into Student values('201215121','李勇','男',20,'CS');
insert into Student values('201215122','刘晨','女',19,'CS');
insert into Student values('201215123','王敏','女',18,'MA');
insert into Student values('201215125','张立','男',19,'IS');

insert into Course values('1','数据库','5',4);
insert into Course values('2','数学','',2);
insert into Course values('3','信息系统','1',4);
insert into Course values('4','操作系统','6',3);
insert into Course values('5','数据结构','7',4);
insert into Course values('6','数据处理','',2);
insert into Course values('7','PASCAL语言','6',4);

insert into SC values('201215121','1',92);
insert into SC values('201215121','2',85);
insert into SC values('201215121','3',88);
insert into SC values('201215122','2',90);
insert into SC values('201215122','3',80);

3、查询表

select * from Student;
select * from Course;
select * from SC;

代码007普通

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