select * from
   (select 
     s.SEGMENT_NAME, 
     s.SEGMENT_TYPE, 
     (s.BYTES/1024/1024/1024) GB, 
     t.LAST_ANALYZED 
  from 
     dba_segments s,
     dba_tables t
  WHERE
	t.table_name = s.SEGMENT_NAME
  and t.LAST_ANALYZED <trunc(SYSDATE) - 7
	order by 3 desc)
  WHERE
	ROWNUM <=10
  ;