物理备库和快照备库切换

一、物理备库切换快照备库
1.取消备库日志应用
--- 检查备库状态
set pages 100 lines 180
col name for a10
select dbid,name,current_scn,protection_mode,database_role,force_logging,open_mode,switchover_status from gv$database;

-- 取消备库日志应用
alter database recover managed standby database cancel;

2.切换备库为快照备库
-- 执行转换为快照数据库后，备库的开启状态为：MOUNTED
alter database convert to snapshot standby;

-- 开启备库后，数据库开启状态为：READ WRITE
alter database open;

set pages 100 lines 180
col name for a10
select dbid,name,current_scn,protection_mode,database_role,force_logging,open_mode,switchover_status from gv$database;

---停止数据库定时任务
show parameter job_queue_processes;

alter system set job_queue_processes=0;


二、快照备库回切物理备库
1.关闭备库，将备库启动到 mount 状态
shutdown immediate
startup mount

2.执行回切命令
alter database convert to physical standby;

3.再次关闭备库，启动到 open 状态，开启实时应用
-- 关闭备库
shutdown immediate

-- 启动数据库到 open 状态
startup

-- 开始备库实时应用
alter database recover managed standby database using current logfile disconnect from session;

4.查看备库状态
set pages 100 lines 180
col name for a10
select dbid,name,current_scn,protection_mode,database_role,force_logging,open_mode,switchover_status from gv$database;