Backing Up Oracle - Computing at Cornell

E.3.4 Summary
In our second test, the tablespace USERS was still available even after the
datafile was deleted. We were able to add more transactions to the
tablespace. Then we restarted the instance. The startup was not able to open
database because the datafile was missing. So it remained in mount mode.
Here, we did a close database recovery. Below were the steps we performed:
1. Make sure that the datafile is online by querying V$DATAFILE. In our
case, the datafile was online, otherwise, we would have issued this
command using sqlplus or svrmgrl:
alter database datafile ‘/hewdb/tokyo/users01.dbf’ online;
2. Run the RMAN recovery command:
rman target / catalog rman2/rman@rman cmdfile
‘/orc8/app/oracle/product/815/admin/tokyo/adhoc/recover’
3. Using sqlplus or svrmgrl, open the database:
alter database open;
Our recovery tests were able to recover the database to its latest committed
transaction.
In summary, TDP for ESS reduces resource contention by offloading the
backup process to a backup machine. The backup process can be done
offline in the backup machine which gives better performance. The production
database remains online and its activity is not affected by a backup process.
It is therefore recommended to use TDP for ESS to perform database backup
on databases which require maximum database availability.
If you have to do tablespace backup, the regular RMAN tablespace backup
can be used for smaller tablespaces. For larger tablespaces, TDP for ESS
can be used when it becomes available. As of this writing, TDP for ESS
version 1.1 only supports database backup.
For backing up archive logs, the only option as the time of writing is to use
regular RMAN commands.
Appendix E. TDP for IBM ESS for Oracle databases 243