签到查询的SQL语句

--------------------------==================================================================
--签到系统小练习
---=========================================================================================
Create table dbo.Sign
(
StuID int,
StuName varchar(100),
SignTime varchar(100),
SignCourse varchar(100),
ClassName varchar(100)
)

Create table dbo.Course
(
CourseName varchar(100),
CourseTime varchar(100),
TeacherID int,
ClassName varchar(100),
)

----insert插入数据
insert into dbo.Sign
select 2006341329,'柴兴博','2006-6-19','代码开发','计科3班' union all
select 2006341329,'柴兴博','2006-6-20','代码开发','计科3班' union all
select 2006341329,'柴兴博','2006-6-21','代码开发','计科3班' union all
select 2006341329,'柴兴博','2006-6-19','体系架构','计科3班' union all
select 2006341329,'柴兴博','2006-6-20','体系架构','计科3班' union all
select 2006341329,'柴兴博','2006-6-21','体系架构','计科3班' union all
select 2006341329,'柴兴博','2006-6-19','电子商务','计科3班' union all
select 2006341329,'柴兴博','2006-6-20','电子商务','计科3班' union all
select 2006341329,'柴兴博','2006-6-21','电子商务','计科3班' union all
select 2006341329,'柴兴博','2006-6-19','需求分析','计科3班' union all
select 2006341329,'柴兴博','2006-6-20','需求分析','计科3班' union all
select 2006341329,'柴兴博','2006-6-19','需求分析','计科3班'

insert into dbo.Sign
select 2006341330,'肖睿','2006-6-19','代码开发','计科3班' union all
select 2006341330,'肖睿','2006-6-20','代码开发','计科3班' union all
select 2006341330,'肖睿','2006-6-21','代码开发','计科3班'

insert into dbo.Course
select '代码开发','2006-6-19',1001,'计科3班' union all
select '代码开发','2006-6-20',1001,'计科3班' union all
select '代码开发','2006-6-21',1001,'计科3班' union all
select '代码开发','2006-6-22',1001,'计科3班' union all
select '代码开发','2006-6-23',1001,'计科3班' union all
select '代码开发','2006-6-24',1001,'计科3班'

---select查询全部
select * from dbo.Sign
select * from dbo.Course

--查询学号及签到次数
select
 distinct one.StuID,
 (select COUNT(Sign.StuID) from dbo.Sign where SignCourse='代码开发' and ClassName='计科3班' and Sign.StuID=one.StuID) as 签到次数 
from dbo.Sign one where one.SignCourse='代码开发' and one.ClassName='计科3班'

--销毁以上俩表
drop table dbo.Sign
drop table dbo.Course