RIYOSU

select s.start_time,
instance_number||':'||event_name,
sum(nvl(total_waits,0)),
sum(nvl(TIME_WAITED_MICRO,0))
from
(select snap_id,
        instance_number,
        event_name,
        total_waits,
        time_waited_micro
        from dba_hist_system_event) x,
(select snap_id,
        max(to_char((trunc(begin_interval_time, 'mi')),'DD-MON-YYYY HH24:MI')) as start_time,
        max(to_char((trunc(end_interval_time, 'mi')),'DD-MON-YYYY HH24:MI')) as end_time
        from dba_hist_snapshot
        where begin_interval_time >= sysdate -1
        group by snap_id
        ) s
where s.snap_id = x.snap_id
group by s.snap_id,s.start_time,
instance_number||':'||event_name
order by s.snap_id