You are peer reviewing a fellow DBAs backup plan for his NOARCHIVELOG mode
database, as shown here:
1. Put the tablespaces in backup mode.
2. Back up the datafiles for all tablespaces.
3. Take the tablespaces out of backup mode.
4. Back up all archived redo logs.
Your colleague asks for you to comment on his plan. Which response would be correct?
A.
The plan will work as is.
B.
The plan needs to be modified to allow for an archive-log switch after step 3.
C.
The plan needs to be modified so that a backup of the archived redo logs occurs before
step 1.
D.
The plan needs to be adjusted to shut down the database after step 1 and to restart the
database after step 2.
E.
The plan cannot work as presented.
Explanation:
Without command ALTER SYSTEM SWITCH LOGFILE, the backup of archive redo logs will
be useless.
Online (hot) Backup is only possible in Archivelog mode. Thus, the correct answer is E.
SQL> archive log list;
Database log mode No Archive Mode
Automatic archival Disabled
Archive destination /oraclebase/fra/archivelog
Oldest online log sequence 83
Current log sequence 85
SQL>
SQL>
SQL>
SQL> alter system switch logfile;
System altered.
SQL>
Noarchive log mode, you can execute a log switch.
B is not correct. Correct one is E
SQL> select * from v$version where banner like ‘%Database%’;
BANNER
——————————————————————————–
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 – 64bit Production
SQL> archive log list
Database log mode No Archive Mode
Automatic archival Disabled
Archive destination USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence 10
Current log sequence 12
SQL> alter tablespace USERS begin backup;
alter tablespace USERS begin backup
*
ERROR at line 1:
ORA-01123: cannot start online backup; media recovery not enabled
yes E is the right answer!