--10、查询出学生的姓名及家庭地址，如果地址为空显示“未填写家庭地址”
select Studentname,isnull( homeaddr, '未填写家庭地址') from Student--11、创建一个函数：完成通过教师号查询教师姓名的功能
create function te(@tid as char(20))
returns char(15)
begin
declare @tname char(15) 
select @tname=Teachername from teacher where TeacherID=@tid
return @tname
end--12、计算1*2*3*…*10的结果。
declare @i int,@sum int;
set @i=1;
set @sum=0;
while(@i<=10)
begin
set @sum=@sum*@i;
set @i=@i+1;
end
print'1*2*3*…*10=';
print @sum;--13．创建一个随机产生9位数的程序
select floor (rand (1)*100000000)--15、创建一个函数：完成通过系部名称查询系部学生人数的功能create function mm(@dname as char(25))
return  int
begin
declare @pcount int
select @pcount =COUNT(student.StudentID) from Student join class on class.ClassID=Student.ClassID 
join Department on Department.DepartmentID=Class.DepartmentID where DepartmentName=@dname
return @pcount
end