建学生表
create table student
(snochar(9) primary key,
snamechar(20) unique,
ssex char(2),
sage smallint,
sdept char(20)
);
create table course
(cnochar(4) primary key,
cnamechar(40) no null,
cpnochar(4),
ccreditsmallint,
foreignkey (cpno) references course(cno)
);
create table sc
(snochar(9),
cnochar(4),
gradesmallint,
primarykey(sno, cno),
foreignkey(sno) references student(sno),
foreignkey(cno) references course(cno)
);
insert
into student(sno,sname,ssex,sage,sdept)
values(‘201215121′,’李勇’,’男’,20,’cs’)；
insert
into student (sno,sname,ssex,sage,sdept)
values (‘201215122′,’刘晨’,’女’,19,’cs’);
insert
into student (sno,sname,ssex,sage,sdept)
values (‘201215123′,’王敏’,’女’,18,’ma’);
insert
into student (sno,sname,ssex,sage,sdept)
values (‘201215125′,’张立’,’男’,19,’is’);
insert
into course(cno,cname,cpno,ccredit)
values(‘2’,’数学’,’null’,’2’);
insert
into course(cno,cname,cpno,ccredit)
values(‘6’,’数据处理’,’null’,’2’);
insert
into course(cno,cname,cpno,ccredit)
values(‘4’,’操作’,’6’,’3’);
insert
into course (cno,cname,cpno,ccredit)
values(‘7′,’pscal语言’,’6′,’4′);
insert
into course (cno,cname,cpno,ccredit)
values(‘5′,’数据结构’,’7′,’4′);
insert
into course (cno,cname,cpno,ccredit)
values(‘1′,”,’5′,’4’);
insert
into course (cno,cname,cpno,ccredit)
values(‘3′,’信息系统’,’1′,’4′);
insert
into sc(sno,cno,grade)
values(‘200215121’,’1’,’92’);
insert
into sc (sno,cno,grade)
values(‘200215121′,’2′,’85’);
insert
into sc (sno,cno,grade)
values(‘200215121′,’3′,’88’);
insert
into sc (sno,cno,grade)
values(‘200215122′,’2′,’90’);
insert
into sc (sno,cno,grade)
values(‘200215122′,’3′,’80’);