select * from ( select rownum as rn ,a.* from ( select
* from page a where object_id >1000 and owner='SYS'
order by object_id desc )a where rownum<=40 ) a where rn>=21
select * from ( select rownum as rn ,a.* from ( select
* from page a where object_id >1000 and owner='SYS'
order by object_id desc )a where rownum<=40 ) a where rn>=21