SQLServer 2008 データ挿入・更新用ストアドプロシージャ

 Create proc sp_Insert_Student
   @No char(10),
   @Name varchar(20),
   @Sex char(2),
   @Age int,
   @rtn int output
 as
 declare
   @tmpName varchar(20),
  @tmpSex char(2),
  @tmpAge int
  
  if exists(select * from Student where No=@No)
    begin
      select @tmpName=Name,@tmpSex=Sex,@tmpAge=Age from Student where No=@No
      if ((@tmpName=@Name) and (@tmpSex=@Sex) and (@tmpAge=@Age))
        begin
          set @rtn=0 -- with the same data, return the value directly
        end
      else
        begin
          update Student set Name=@Name,Sex=@Sex,Age=@Age where No=@No
          set @rtn=2 ---with the same primary key, update the data
        end
    end
  else
    begin
      insert into Student values(@No,@Name,@Sex,@Age)
      set @rtn=1 --no identical data, insert
    end

 declare @rtn int
 exec sp_Insert_Student '1101','Zhang San','Male',23,@rtn output
 
 if @rtn=0
   print 'The same one already exists.'
 else if @rtn=1
   print 'Inserted successfully.'
 else
   print 'Update successful'