动态很多时候我们需要得到交叉列表，最近做课程设计就需要这样的功能，比如要得到一个班某学期的成绩，因为每一学期所学科目和数量都是变化的，这就要求动态的查询以得到成绩。而且得到这样的显示形式：
studentID studentName courseName1 courseName2 courseName3 ……
1 lupenda 66 77 88 ……
。
。
。
下面的例子就是为了实现上面的功能，该存取过程涉及3张表：

Course表：
CourseID，CourseName,Duration,[Year],MajorID,Semester

StudentData表：
StudentID,StudentName,ClassID……

Student_Course表：
StudentID，CourseID，Score


--根据不同参数取得成绩
--可以得到某学期，某专业，某班级，某学生的成绩

CREATE procedure GetScore
Year int ,Semester bit ,MajorID int = null,ClassID int = null,StudentID int = null
as

declare var varchar(200)
declare sql varchar(8000)

set sql=''

--放进临时表
select distinct CourseName into #tb from Course where Course.Year = Year and Course.Semester = Semester

--声明游标
declare cur cursor
for select CourseName from #tb
open cur
fetch next from cur into var
while fetch_status=0
begin
set sql = sql + 'sum(case when Course.CourseName = ''' +var+ ''' then Student_Course.Score else 0 end) as '+ var+','
fetch next from cur into var
end

set sql = left(sql,len(sql)-1)


set sql = 'select Class.ClassName as 班级,Student_Course.StudentID as 全学号,StudentData.StudentName as 姓名, ' +sql+ '
from StudentData,Student_Course,Course ,Class
where Student_Course.CourseID = Course.CourseID
and StudentData.StudentID = Student_Course.StudentID
and StudentData.ClassID = Class.ClassID'


--根据输入参数的不同创建查询语句
if Year is not null
set sql = sql+ ' and Course.Year = '+ Cast( Year as varchar(4)) --强制转换为字符串

if Semester is not null
set sql = sql+ ' and Course.Semester = '+ Cast( Semester as varchar(1))

if MajorID is not null
set sql = sql+ ' and Course.MajorID = '+ Cast( MajorID as varchar(4))

if ClassID is not null
set sql = sql+ ' and StudentData.ClassID = '+ Cast( ClassID as varchar(4))

if StudentID is not null
set sql = sql+ ' and StudentData.StudentID = '+ Cast( StudentID as varchar(8))

set sql = sql+ 'group by Class.ClassName,Student_Course.StudentID,StudentData.StudentName order by Student_Course.StudentID '


exec(sql)

deallocate cur
drop table #tb
GO

至此，该存取过程实现了我们想要的功能.第一次发文章，请大家多多支持！