sqlserver：

select convert(varchar(7),dateadd(mm,-t.number,getdate()),120)

from

(select number from master..spt_values where type="P") t

where year(dateadd(mm,-t.number,getdate()))=year(getdate())

order by convert(varchar(7),dateadd(mm,-t.number,getdate()),120)

oracle：

select to_char(add_months(sysdate, -t.rn), "yyyy-mm")

from dual a, (select rownum - 1 rn from dual connect by rownum

where to_char(add_months(sysdate, -t.rn), "yyyy") =

to_char(sysdate, "yyyy")

order by to_char(add_months(sysdate, -t.rn), "yyyy-mm")