order by 学号 desc
3.05
select 学号,姓名 from xxx_student
where 学号 like '1998%'and 姓名 like'李%' go
3.06
select 学号,课程代号,平时*0.1+期中*0.2+期末*0.7 as 总评 from xxx_grade
3.07
declare @w int
exec 各学分课程数 '2',@w output print @w
3.08
select 课程数=count(*),学时总数=36*sum(cast(周学时 as float)), 学分总数=sum(cast(学分 as float)) from xxx_grade,xxx_course
where xxx_grade.课程代号=xxx_course.课程代号
3.09
select 学号 from xxx_student
where 学号 in (select 学号 from xxx_course group by 学号 having count(课程代号)>=3) go
3.10
create view view1 as
select xxx_student.姓名 as 姓名,
count(xxx_grade.课程代号) as 选修课程门数,sum(xxx_course. cast(周学时 as float)) as 总周学时,
sum(xxx_course.cast(学分 as float))as总学分 , sum((xxx_grade.cast(平时as float)*0.1+xxx_grade.
期中*0.2+xxx_grade.期末*0.6)*xxx_course.学分)/sum(xxx_course.学分) as 加权平均分 from xxx_student
inner join xxx_grade on xxx_student.学号=xxx_grade.学号