ORACLE等待事件监控

　　监控oracle的等待事件　　select event,　　sum(decode(wait_Time, 0, 0, 1)) "Prev",　　sum(decode(wait_Time, 0, 1, 0)) "Curr",　　count(*) "Tot"　　from v$session_Wait　　group by event　　order by 4;　　1 等待事件