存储过程输出参数(不能添加重复数)

------------------------------------
--用途：员工管理 
--时间：2011-2-24 8:18:31
------------------------------------ 
alter proc DKI_StaffManage
(
   @CMD varchar(20)='',
   @staffcode varchar(50)='',
   @staffName varchar(50)='', 
   @flg int=0,              
   @returnvalues int=0 output
)
as
begin tran
if(@CMD='select')          
  begin  
      if(@flg=1) 
        begin   
           select top 100 * from Opt_DKI_Staff order by staffID desc
        end
       else if(@flg=2)   ---2为查询
         begin
          select * from Opt_DKI_Staff where 
         end 
  end     
else if(@CMD='insert')
   begin    
  if (select count(*) from Opt_DKI_Staff where 0">StaffCode=@staffcode)>0
  begin     
    set @returnvalues=0         
  end 
  else
  begin 
    insert into Opt_DKI_Staff (StaffCode,StaffName) values (@staffcode,@staffName) 
    set @returnvalues=1   
  end 
   end
else if(@CMD='update')
   begin     
   update Opt_DKI_Staff set where   
   end 
else if(@CMD='delete')
  begin
  delete Opt_DKI_Staff where   
  end
commit tran
return