To accomplish user-managed backup for the USERS tablespace, you issued the following
command to put the database in backup mode:
SQL> ALTER TABLESPACE users BEGIN BACKUP;
While copying the file to the backup destination a power outage caused the instance to te minate
abnormally.
Which statement is true about the next database startup and the USERS tablespace?
A.
The database will open, and the tablespace automatically comes out of the backup mode.
B.
The database will be mounted, and recovery must be performed on the USERS tablespace.
C.
The database will be mounted, and data files in the USERS tablespace must be taken out of
the backup mode.
D.
The database will not be mounted, and you must restore all the data files for the USERS
tablespace from the backup, and perform recovery.
Explanation:
http://www.informit.com/articles/article.aspx?p=30348
Database Crashes During Hot Backup
There can be many reasons for the database to crash during a hot backup-a power outage or
rebooting of the server, for example. If these were to happen during a hot backup, chances are
that tablespace would be left in backup mode. In that case you must manually recover the files
involved, and the recovery operation would end the backup of tablespace. It’s important to check
the status of the files as soon as you restart the instance and end the backup for the tablespace if
it’s in backup mode.
select a.name,b.status from v$datafile a, v$backup b
where a.file#=b.file# and b.status=’ACTIVE’;
or
select a.tablespace_name,a.file_name,b.status from dba_data_files a,
v$backup b
where a.file_id=b.file# and b.status=’ACTIVE’;
This statement lists files with ACTIVE status. If the file is in ACTIVE state, the corresponding
tablespace is in backup mode. The second statement gives the tablespace name also, but this
can’t be used unless the database is open. You need to end the backup mode of the tablespace
with the following command:
alter tablespace tablespace_name end backup;