Oracle数据库和session等待事件有关的几个视图 1、v$session:连接将产生会话，当前会话的信息保存在v$session中，连接断开后消失； 2、v$session_wait:将当前会话中正在等待的会话状态复制一份到视图，断开后消失(等待会话生命周期最后1次等待)； 3、v$sessi
Oracle数据库和session等待事件有关的几个视图
1、v$session:连接将产生会话，当前会话的信息保存在v$session中，连接断开后消失； 2、v$session_wait:将当前会话中正在等待的会话状态复制一份到视图，断开后消失(等待会话生命周期最后1次等待)； 3、v$session_wait_history：保存每个活动session在v$sess
1、v$session:连接将产生会话，当前会话的信息保存在v$session中，连接断开后消失；
2、v$session_wait:将当前会话中正在等待的会话状态复制一份到视图，断开后消失(等待会话生命周期最后1次等待)；
3、v$session_wait_history：保存每个活动session在v$session_wait中最近10次的等待事件(等待会话生命周期最后10次等待)；
4、ASH(v$active_session_history):在内存中保存，每秒从v$session_wait中采样一次(等待会话每秒的快照)
5、AWR：ASH数据每小时将数据采样写入存到磁盘中AWR(dba_hist..)，默认保留7天，每小时一次
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