Create Function FReturn(@sid Varchar(50))
Returns Varchar(8000)
as
Begin
Declare @str Varchar(8000)
Set @str = ''
Select @str = @str + cast(name as Varchar(50)) + ',' from ClassNo Where Class =@grade
Set @str = SubString(@str,1,len(@str)-1)
Return(@str)
End
Select Distinct grade, FReturn(grade) From D_student
select grade,name from D_student group by grade,name
姓名也要分组 如果班级的下面跟着学生姓名 那怎么知道他们是什么班级的