实验七 T-SQL语句高级应用（一）

实验七 T-SQL语句高级应用（一）


1、实验目的

（1）掌握游标、大对象类型数据的基本概念

（2）掌握游标处理结果集的基本过程

2、实验内容

（1）使用游标输出学生姓名、选修课程名称和期末考试成绩，形成报表格式。

declare @sname
nchar(10)
declare @cname
nchar(10)
declare @final
nchar(10)

DECLARE Stu2
CURSOR STATIC
FOR
SELECT sname,cname,final
FROM student,course,score
WHERE student.studentno
= score.studentno
and
course.courseno
= score.courseno
ORDER BY score.studentno

open Stu2

fetch from Stu2
into @sname,@cname,@final
print @sname
+ @cname + @final

while
@@fetch_status = 0
begin
fetch next
from Stu2
into @sname,@cname,@final
print @sname
+ @cname + @final

end
close Stu2
deallocate Stu2

（2）使用游标统计每个学院教师所开课程的选修率。

/*
declare @num
float
declare @monitor
nchar(30)
declare @all
float
declare @avg
float
set @num
= (select
count(*)from student)
declare cou
cursor static
for
select monitor,count(*)
as '人数'
from student,class
where class.classno
= student.classno
group by monitor

open cou
fetch cou
into @monitor,@all
set @avg
= @all / @num
print @monitor
+ cast(@avg
as nchar(8))


while
@@fetch_status = 0
begin
fetch next
from cou
into @monitor,@all
set @avg
= @all / @num
print @monitor
+ cast(@avg
as nchar(8))

end
close cou
deallocate cou

*/

declare @department
nchar(30)
declare @num
int
declare @avg
float
declare cur
cursor static
for
select department,count(*)
as '选修课数'
from class
where
class.classno
in (select student.classno
from studentgroup
byclassno)
group by department

open cur
fetch cur
into @department,@num
set @avg
= @num / (select
count(*)from class
where department =@department)
print @department
print @avg
while
@@fetch_status = 0
begin
fetch next
from cur
into @department,@num
set @avg
= @num / (select
count(*)from class
where department =@department)
print @department
print @avg
end
close cur
deallocate cur

（3）使用游标计算学生期末成绩的等级。

等级分为：90—100 优秀，80-90 良好，70-80，中等，60-70 及格，60以下不及格。

declare @sname
nchar(30)
declare @cname
nchar(30)
declare @final
float
declare stu
cursor static
for
select sname,final,cname
from student,score,course
where student.studentno
= score.studentno
and
course.courseno
= score.courseno

open stu

fetch stu
into @sname,@final,@cname
if @final
>=90
print N'优 '
+ @sname + @cname
else if @final
>=80 and @final
<90
print N'良'+ @sname
+ @cname
else if @final
>=70 and @final
<80
print N'中'+ @sname
+ @cname
else if @final
>=60 and @final
<70
print N'及'+ @sname
+ @cname
else if @final
<60
print N'差'+ @sname
+ @cname

while
@@fetch_status = 0
begin

fetch next
from stu
into @sname,@final,@cname
if @final
>=90
print N'优'+ @sname
+ @cname
else if @final
>=80 and @final
<90
print N'良'+ @sname
+ @cname
else if @final
>=70 and @final
<80
print N'中'+ @sname
+ @cname
else if @final
>=60 and @final
<70
print N'及'+ @sname
+ @cname
else if @final
<60
print N'差'+ @sname
+ @cname
end

close stu
deallocate stu

（4）使用存储过程查看游标属性，理解各列取值的含义。

declare @final2
float
declare @final1
float
declare stu111
cursor
for
select final,final
from score
declare @stu111
cursor
exec teaching1.dbo.sp_cursor_list
@cursor_return = @stu111
output,@cursor_scope
= 2

open stu111
fetch stu111
into @final1,@final1


while
@@fetch_status = 0
begin
fetch next
from @stu111



end
close stu111
deallocate stu111
close @stu111
deallocate @stu111

（5）创建一个文本文件（test101.txt）并将数据利用指定格式符（/）进行分隔排列，文件内容如下：

102512107/c05109/62.00/82.00

1137221508/c08109/95.00/90.00

1137221508/c08123/89.00/85.00

使用BULK INSERT命令将文件插入score表中。

BULK INSERT score
FROM
'D:test.txt'
WITH(FIELDTERMINATOR
='/')