O8i new features questions - 01

[woexpert]

I had a hard time in understanding the following question(s):

Q: Examine this series of commands:

alter database recover managed standby database cancel;
alter database open read only;
alter database recover managed standby database;

At which point in time will the redo log files start?

The Answer is: from the point when sustained recovery was cancelled.

Can someone explain the question in more details?
Thanks a lot!

[tamilselvan]

1 alter database recover managed standby database cancel;

This command is used for cancelling the recovery process of Standby database. Normally I run this command, after completing the recovery (applying the archived redo log files from production to Standby db), and then shutdown the standby database.

2 alter database open read only;
This is used to open the standby db in read only mode. It means no write operation is done against the Standby database. In order to do that you need to create Locally Managed Temp Tablespace and assign it to all users. Otherwise the query will fail.

3 alter database recover managed standby database;
When the new archived redo files come from production db to standby db, I run this command to start the recovery process.