Performing Oracle Advanced Recovery - OCP: Oracle Database 12c Administrator Certified Professional - page 301

In this case, we are executing a TSPITR of the USERS tablespace. We want to recover the
entire USERS tablespace to 10/6/2013 at 22:42:00 hours. The AUXILIARY DESTINATION
clause, discussed earlier, indicates where we want RMAN to create the auxiliary
instance database files—in this case, the directory c:\oracle\auxiliary .
Now that you have executed the RECOVER TABLESPACE command, what happens next?
3. Create the TSPITR auxiliary instance.
TSPITR requires the use of an auxiliary instance just as database duplication does.
The auxiliary instance (in RMAN output, it's called an automatic instance ) is the
database that will be used to perform the TSPITR. It is a transient database, used just
long enough to restore the tablespaces, export the database, and finish the TSPITR.
The main difference here is that once RMAN is done with the TSPITR, the auxiliary
instance is no longer needed.
4. Check the TSPITR transport set.
When you start the TSPITR with the RECOVER TABLESPACE command, RMAN will
check that the tablespace you want to recover can actually be recovered. It does this by
checking the transport set to ensure that it's wholly self-contained. See the next section,
“Checking the Transport Set,” for more information on this process and why it's needed.
5. Create the auxiliary instance.
Once RMAN confirms that the tablespace set can be transported, it will create the aux-
iliary instance, start it, and connect to it. This is nice because you will not have to create
the auxiliary instance. You can opt to create the auxiliary instance yourself if there are
specific reasons to do so. RMAN will create a control file for the auxiliary instance.
6. Take the target database tablespaces offline.
Once the auxiliary instance has been created, the tablespaces on the target database to
be moved will be taken offline. This implies that the data in these databases will not be
available to users until the tablespaces are brought back online. Since you are restoring
these tablespaces to a different point in time, the data the users will see the next time the
tablespaces are brought back online will possibly be very different. Keep this in mind
when doing a TSPITR: You are impacting the entire tablespace or set of tablespaces. If
someone is not aware of what you are doing, you might get a very nasty phone call.
7. Transport the source tablespaces.
Now that the tablespace(s) has been taken offline, RMAN will restore the recovery set
and the auxiliary set from the target database to the auxiliary instance. The recovery set
is the set of tablespaces that you are going to recover with TSPITR. The auxiliary set is
the set of data files that are required to get the auxiliary instance running. This includes
files for the SYSTEM tablespace, the UNDO tablespace, and the SYSAUX tablespace and
tablespace tempfiles.
8. Recover the auxiliary-instance database.
Once the auxiliary set and the recovery set are restored, RMAN will proceed to
recover the auxiliary-instance database to the point in time identified when the RMAN
RECOVER command was issued. Once the restore is complete, the auxiliary-instance
database will be opened.