if not exists(select * from syscolumns where name = 'ACH04' and object_Name(id)='ACH1')
  ALTER TABLE ACH1 ADD ACH04 VARCHAR(2)
GO
update ACH1 set ACH04=case when ACH02='¼×' then '4' when ACH02='ÒÒ' then '3' when ACH02='±û' then '2' when ACH02='¶¡' then '1' end where ACH04 is NULL
update ACH1 set ACH02=case when ACH04='1' then 'Ò»' when ACH04='2' then '¶þ' when ACH04='3' then 'Èý' when ACH04='4' then 'ËÄ' end
GO
select * from ACH1