三種方法：增加一個自動成長的列

--eg1:表裡增加欄位CREATE TABLE t7(id int IDENTITY(100,1));--eg2:--自動成長的函數 create   function   iden()     returns   int     as     begin         declare   @a1   int         set   @a1   =   1         while   exists(select   *   from   table_name   where   id=@a1)             set   @a1   =   @a1   +   1         return   @a1     end --eg3: 虛擬表select   identity(int,1,1)   kk,*   into   #t   from   T select   #t