数据库12.03实验

数据库实验

实验十二：T-SQL(10)
1  实验目的
    1．  熟悉数据库的交互式SQL工具。
    2．  熟悉通过SQL对数据库进行操作。
    3．  完成作业的上机练习。
2  实验平台
利用SQLServer及其交互式工具SSMS来熟悉T-SQL。
3  实验内容及要求
     基于student、course、sc表，用SQL语句实现如下要求，填写实验报告，记录所有的实验用例。
1.  创建一个视图显示学号、姓名、数据结构和数据库原理课程的成绩
2.  查询选修了全部课程的同学的学号、姓名；
3.  查询平均成绩在60分以上的同学的学号、姓名；
4.  查询平均成绩在全系平均成绩之上的同学的学号、姓名；

0 建表代码

create database Students
on
primary(name=Students,
   filename='D:\test\test.mdf',
size=4mb,
maxsize=10mb,
filegrowth=2mb
  )
log on
(name=Studentslog,
filename='D:\test\testlog.ldf',
size=1mb,
maxsize=5mb,
filegrowth=1mb
)
use Students;
create table Student
(
sno char(8) not null primary key,
Sname char(15) null,
Ssex char(4) null,
Sage int null,
Sdept char(10) null
)
create table Course
(
Cno char(6) not null,
Cname char(10),
Cpno char(6),
Ccredit int null,
primary key(cno),
)
go 
create table SC
(
Sno char(8) not null foreign key references Student(sno),
Cno char(6) not null foreign key references course(cno),
primary key(Sno,Cno),
Grade int  null
)
insert into Student values('19130201','丁鹏','男',20,'Software')
insert into Student values('19130202','王韵婷','女',20,'Software')
insert into Student values('19130203','尹嘉琪','男',18,'Software')
insert into Student values('19130204','卢冬冬','男',20,'Software')
insert into Student values('19130205','史逸凡','男',19,'Software')
insert into Course values('1','数据库',5,4)
insert into Course values('2','数学',null,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',7,5)
insert into Course values('6','数据处理',null,2)
insert into Course values('7','PASCAL语言',6,4)
insert into SC values('19130201',1,99)
insert into SC values('19130202',5,95)
insert into SC values('19130203',3,100)
insert into SC values('19130205',1,93)
insert into SC values('19130204',5,92)
alter table course add  foreign key(cpno) references course(cno)
select * from Course;
select * from SC;
select * from Student;

1. 创建一个视图显示学号、姓名、数据结构和数据库原理课程的成绩

create view Is_S1(sno,sname,grade1,grade2)
as
select a.sno,a.sname,b.Grade,c.Grade
from Student a
left outer join
(select sno,grade from sc,course where sc.cno=cource.cno and course.cname='数据结构') b on b.sno=a.sno
left outer join
(select sno,grade from sc,course where sc.cno=cource.cno and course.cname='数据库') c on c.sno=a.sno

2. 查询选修了全部课程的同学的学号、姓名

select a.sname,a.sno
from Student a
where not exists
(select *
 from Course
 where not exists
  (select *
   from SC
   where Sno= a.Sno
   and Cno= Course.Cno
   )
)

3. 查询平均成绩在60分以上的同学的学号、姓名

select a.sno, b.sname,a.平均成绩
from Student b,
(
select sno,AVG(grade) as '平均成绩'
from sc 
group by sno 
having AVG(grade)>60
) a 
where a.sno = b.sno

4. 查询平均成绩在全系平均成绩之上的同学的学号、姓名

go 
create view S_G(sno,sname,Gavg)
as
select student.sno,sname,AVG(grade)
from sc,student
where student.sno=sc.sno
group by student.sno,student.sname
go
select *
from S_G
where Gavg>(select AVG(grade) from sc)