# 班级表
create table class(
cid int primary key auto_increment,
caption char(16)
);
# 学生表
create table student(
sid int primary key auto_increment,
sname char(16),
gender enum('male','female'),
class_id int ,
foreign key(class_id) references class(cid)
on update cascade
on delete cascade
);
# 老师表
create table teacher(
tid int primary key auto_increment,
tname char(16)
);
# 课程表
create table course(
cid int primary key auto_increment,
cname char(16),
teacher_id int,
foreign key(teacher_id) references teacher(tid)
on update cascade
on delete cascade
);
# 成绩表
create table gender(
sid int primary key auto_increment,
student_id int,
course_id int,
number int,
foreign key(student_id) references student(sid)
on update cascade
on delete cascade,
foreign key(course_id) references course(cid)
on update cascade
on delete cascade
);