SQL with the highest I/O in the past one day

select * from 

(

SELECT /*+LEADING(x h) USE_NL(h)*/ 

       h.sql_id

,      SUM(10) ash_secs

FROM   dba_hist_snapshot x

,      dba_hist_active_sess_history h

WHERE   x.begin_interval_time > sysdate -1

AND    h.SNAP_id = X.SNAP_id

AND    h.dbid = x.dbid

AND    h.instance_number = x.instance_number

AND    h.event in  ('db file sequential read','db file scattered read')

GROUP BY h.sql_id

ORDER BY ash_secs desc )

where rownum < 10;