sql 存储过程例子和学习demo

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-------------------------------存储过程Study------------------------------
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--删除表
drop table student
go
 
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--创建用户信息数据表
create table student
(
    id int identity(1,1),--递增1,
    stuNo varchar(50) primary key, --唯一键
    stuName varchar(50),
    stuAge datetime,
    stuSex varchar(5)        
)
 
--创建用户分数数据表
create table course
(
    id int identity(1,1),--递增1,
    stuNo varchar(50),
    courseName varchar(50),
    courseScore decimal    
)
 
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--插入数据
--插入单条数据
insert into student(stuNo,stuName,stuAge,stuSex) values(‘01‘,‘王男‘,‘1996-08-27 09:00:00.000‘,‘男‘)
 
--多数量插入数据
--SQL Server2008特有的插入
insert into student values(‘02‘,‘杨幂‘,‘1995-4-20 6:0:0‘,‘女‘),
                          (‘03‘,‘程峰‘,‘1988-9-17 15:30:0‘,‘男‘)
                          
insert into course values(‘02‘,‘思想政治‘,‘85.5‘),
                         (‘02‘,‘数学‘,‘70‘),
                         (‘02‘,‘语文‘,‘80‘),
                         (‘02‘,‘物理‘,‘90‘),
                         (‘02‘,‘化学‘,‘65‘),
                         (‘02‘,‘英语‘,‘96‘)
                         
insert into course values(‘03‘,‘思想政治‘,‘60‘),
                         (‘03‘,‘数学‘,‘65‘),
                         (‘03‘,‘语文‘,‘84‘),
                         (‘03‘,‘物理‘,‘70‘),
                         (‘03‘,‘化学‘,‘76‘),
                         (‘03‘,‘英语‘,‘54‘)                         
                          
 
--使用UNION ALL来进行插入
insert into student 
select ‘04‘,‘wangan‘,‘1895-5-27 14:30:28‘,‘女‘
union all     
select ‘05‘,‘zhangnan‘,‘1990-1-20 19:0:0‘,‘女‘
go
 
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--修改数据
update student set stuSex=‘男‘,stuAge=‘2016-5-9 8:0:0‘ where stuName=‘王男‘ 
go
 
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--删除数据
delete from student where stuNo=01
go
 
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--存储过程查询所有数据
--begin...end 类似编程语言中的{}
create proc stu1
as
begin
    select * from student;
end
go
 
exec stu1
go
 
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--存储过程根据条件用户名查询用户信息
create proc stu2
@sname varchar(50)   --声明全局变量
as
begin
    select * from student s where s.stuName=@sname;
end
go
 
exec stu2 ‘王男‘
go
 
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--存储过程内部设定用户名查询用户信息
create proc stu3
@sname varchar(50)=‘王男‘
as 
begin
    select * from student s where s.stuName=@sname; 
end
go
 
exec stu3 
go
 
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--存储过程根据用户名查询是否存在这个用户信息
create proc stu4
@sname varchar(50),
@result varchar(8) output --输出参数
as
begin
     if (select COUNT(1) from student s where s.stuName=@sname)>0
     --if exists (select COUNT(1) from student s where s.stuName=@sname)
     set 
        @result=‘存在!‘
     else
     set 
        @result=‘不存在!‘
end
go
 
 
declare @result varchar(8)
exec stu4 ‘王男1‘,@result output
print @result
go
 
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--存储过程内部设定局部变量用户名来查询用户信息
create proc stu5
as
declare @sname varchar(50)  --局部变量声明
set @sname=‘杨幂‘
begin
    select * from student s where s.stuName=@sname
end
go
 
exec stu5
go
 
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--存储过程根据条件用户学号查询用户名
create proc stu6
@stuNo varchar(50)
as
declare @sname varchar(50)
set @sname=(select s.stuName from student s where s.stuNo=@stuNo)
select @sname
go
 
exec stu6 ‘01‘
go
 
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--存储过程插入用户信息
create proc stu7
@stuNo varchar(50),
@stuName varchar(50),
@stuAge datetime,
@stuSex varchar(5)
as 
begin
    insert into student 
        (stuNo,stuName,stuAge,stuSex)
    values 
        (@stuNo,@stuName,@stuAge,@stuSex) 
end
go
 
exec stu7 ‘07‘,‘王莽‘,‘2000-9-9 9:9:9‘,‘女‘
go
 
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--存储过程根据用户名来删除对应的用户信息
--@@rowcount返回操作条数
--return返回信息，终止下面的操作
create proc stu8
@stuName varchar(50)
as
begin
    delete from student where stuName=@stuName
    return @@rowcount
end
go
 
declare @result varchar(50)
exec @result=stu8 ‘王莽‘
select @result as ‘删除条数‘
--print @result
go
 
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--存储过程根据用户学号来查询他的平均分
create proc stu9
@stuNo varchar(50),
@avg int output
as 
begin
    set @avg=(select AVG(courseScore) from course where stuNo=@stuNo)
    --等同
    --select @avg=AVG(courseScore) from course where stuNo=@stuNo
end
go
 
declare @avg int
exec stu9 ‘02‘,@avg output
print @avg
go
 
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--存储过程根据用户学号来联合查询用户信息和课程信息
create proc stu10
@stuNo varchar(50)
as
    select c.stuNo,s.stuName,s.stuAge,s.stuSex,c.courseName,c.courseScore from student s join course c on s.stuNo=c.stuNo where s.stuNo=@stuNo
go
 
exec stu10 ‘02‘
go
 
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--存储过程判断学号是否存在，不存在，插入用户信息，返回消息；存在，返回信息
create proc stu11
@stuNo varchar(50),
@stuName varchar(50),
@stuAge datetime,
@stuSex varchar(5),
@result varchar(50) output
as
    if exists (select * from student where stuNo=@stuNo)
        begin
            set @result=‘对不起，学号已存在!‘
        end        
    else
        begin
            insert into student 
                (stuNo,stuName,stuAge,stuSex)
            values 
                (@stuNo,@stuName,@stuAge,@stuSex)
            set @result=‘恭喜你，用户信息插入成功!‘     
        end
go
 
declare @result varchar(50)
exec stu11 ‘06‘,‘王忠磊‘,‘1980-8-8 8:9:0‘,‘男‘,@result output
print @result
 
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--存储过程查询当前用户的平均成绩与总的平均成绩之间的关系
create proc stu12
@stuNo varchar(50)
as
declare @curAvg decimal(18,2)
declare @totalAvg decimal(18,2)
if exists(select * from course where stuNo=@stuNo)
    begin
        set @totalAvg=(select AVG(courseScore) from course)
        select @curAvg=AVG(courseScore) from course where stuNo=@stuNo
        print (‘总的平均分:‘+convert(varchar(18),@totalAvg))
        print (‘该生的平均分:‘+convert(varchar(18),@curAvg))
        if @curAvg>@totalAvg
            print ‘高于平均水平!‘
        else 
            print ‘低于平均水平!‘    
    end
else
    print ‘该生对应的分数信息不存在,请重新查询!‘
go
 
exec stu12 ‘03‘
go