View history wait events

In the past, what view can we find the waiting events? 1. select * from (selectevent, total_waits, time_waited, wait_classfromv $ system_eventwherewait_classIdleorderby3desc) whererownum50; 9iselect * from (selectevent,

In the past, what view can we find the waiting events? 1. select * from (select event, total_waits, time_waited, wait_class from v $ system_event where wait_classIdle order by 3 desc) where rownum = 50; 9i select * from (select event,

In the past, what view can we find the waiting events?

1. Since the instance was started

Select * from (select event, total_waits, time_waited, wait_class from v $ system_event where wait_class <> 'idle' order by 3 desc) where rownum <= 50; 9i select * from (select event, total_waits, time_waited from v $ system_event where event not in ('rdbms ipc message', 'pmon timer', 'smon timer ', 'SQL * Net message from client', 'rdbms ipc reply',' SQL * Net more data from client') order by 3 desc) where rownum <= 50;

2. Historical wait events of connected sessions

Select * from (select event, wait_class, sum (total_waits), sum (time_waited) from v $ session_event where wait_class <> 'idle' group by event, wait_class order by sum (time_waited) desc) where rownum <20;
9i select * from (select event, sum (total_waits), sum (time_waited) from v $ session_event where event not in ('rdbms ipc message', 'pmon timer ', 'smon timer', 'SQL * Net message from client', 'rdbms ipc reply',' SQL * Net more data from client') group by event order by sum (time_waited) desc) where rownum <20;

3. Historical wait event information for a SESSION currently connected

Select * from (select sid, event, total_waits, time_waited from v $ session_event where sid = & 1 order by sid asc, time_waited desc) where event not like '% rdbms ipc %' and event not like '% SQL * Net message % ';
9i: select sid, event, total_waits, time_waited from v $ session_event where sid in (& 1) order by sid asc, time_waited desc

Note: total_waits indicates the total number of waits, and time_waited is important. This reflects the user's waiting experience. The time_waited value is 1% seconds.