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  create view grade_student(ѧºÅ,ÐÕÃû,Ñ¡¿ÎÃÅÊý,ƽ¾ù·Ö,×î¸ß·Ö,×îµÍ·Ö)
as
select sc.sno,sname,count(cno),avg(grade),max(grade),min(grade)
from sc,student 
where student.sno=sc.sno
group by sname,sc.sno
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SQL code:
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if object_id('tb')is not null drop table tb
if object_id('test')is not null drop view test
go

create table tb
(
id int,
date datetime
)
go

alter table tb add default getdate() for date
go

insert into tb(id) select 1
union all select 3
union all select 2
union all select 4
go

create view test
as
select id,date=max(date) from tb
group by id;
go

select * from test
/*
id date
---------------------------------
1 2010-04-26 12:42:53.827
2 2010-04-26 12:42:53.827
3 2010-04-26 12:42:53.827
4 2010-04-26 12:42:53.827
*/

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create view grade_student(ѧºÅ,ÐÕÃû,Ñ¡¿ÎÃÅÊý,ƽ¾ù·Ö,×î¸ß·Ö,×îµÍ·Ö)
as
select sc.sno,sname,count(cno),avg(grade),max(grade),min(grade)
from sc,student  
where student.sno=sc.sno
group by sname,sc.sno


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