REDO Apply on Standby Database does not Proceed After New Database Incarnatio...

刘泽宇

现象：
REDO Apply at Standby Database does not proceed after a new database incarnation is set.

For example, consider the following alert log of the standby database:

2020-07-03T14:48:15.072774+09:00
ALTER DATABASE RECOVER MANAGED STANDBY DATABASE DISCONNECT FROM SESSION
2020-07-03T14:48:15.077454+09:00
Attempt to start background Managed Standby Recovery process (<DB_UNIQUE_NAME>)
Starting background process MRP0
2020-07-03T14:48:15.096816+09:00
MRP0 started with pid=55, OS id=20244
2020-07-03T14:48:15.098011+09:00
Background Managed Standby Recovery process started (<DB_UNIQUE_NAME>)
2020-07-03T14:48:20.103916+09:00
Serial Media Recovery started

IM on ADG: Start of Empty Journal

IM on ADG: End of Empty Journal
MRP0 (PID:20244): Managed Standby Recovery starting Real Time Apply
max_pdb is 3
Media Recovery start incarnation depth : 1, target inc# : 5, irscn : 999999999
stopping change tracking
MRP0 (PID:20244): Media Recovery Waiting for xxxxxxxxx.T-1.S-20
2020-07-03T14:48:21.103414+09:00
Completed: ALTER DATABASE RECOVER MANAGED STANDBY DATABASE DISCONNECT FROM SESSION

原因：
This is caused by user operation.  In this example, this occurred after the following operations were executed against the primary database:

shutdown immediate
startup mount
alter database convert to physical standby;
shutdown immediate
startup
ALTER DATABASE ACTIVATE STANDBY DATABASE;
alter database open;

处理方法：
There is no way to proceed REDO Apply from the situation.  The only option is to recreate the standby database.