QUESTION 142
Your database is in ARCHIVELOG mode. You have two online redo log groups, each of which contains one
redo member. When you attempt to start the database, you receive the following errors:
ORA-00313: open failed for members of log group 1 of thread 1
ORA-00312: online log 1 thread 1: 'D:\REDO01.LOG'
You discover that the online redo log file of the current redo group is corrupted.
Which statement should you use to resolve this issue?
A. ALTER DATABASE DROP LOGFILE GROUP 1;
B. ALTER DATABASE CLEAR LOGFILE GROUP 1;
C. ALTER DATABASE CLEAR UNARCHIVED LOGFILE GROUP 1;
D. ALTER DATABASE DROP LOGFILE MEMBER 'D:\REDO01.LOG';
Answer: C
同3题：http://blog.csdn.net/rlhua/article/details/14057145
Explanation/Reference:
Section: Backup, Recovery & Recovery Manager (RMAN)
You should use the ALTER DATABASE CLEAR UNARCHIVED LOGFILE GROUP 1;statement to clear the
corrupted online redo log file. When you issue thisstatement, the contents of the online redo log file are
cleared, and the log file is initialized. Because the log file has not been archived, the UNARCHIVED keyword is
used. This keyword overrides the archiving of the online redo log file in the redo group, and the cleared redo
log files become available for use. Immediately after issuing this statement, you should perform a database
backup.
The option stating that you will use the ALTER DATABASE DROP LOGFILE GROUP 1;statement to resolve
the corrupted online redo log file is incorrect. If you attempt to drop the online redo log group thatbelongs to a
current redo group, you will receive the following errors:
ORA-01623: log 1 is current log for thread 1 cannot drop
ORA-00312: online log 1 of thread 1: 'D:\REDO01.LOG'
The option stating that you will use the ALTER DATABASE CLEARLOGFILE GROUP 1; statement to resolve
the corrupted online redo log file is incorrect. If you attempt to clear an online redo log file that must be
archived without using the UNARCHIVED keyword, you will receive the following errors:
ORA-00350: log 1 of thread 1 needs to be archived
ORA-00312: online log 1 thread 1: 'D:\REDO01.LOG'
The option stating that you will use the ALTER DATABASE DROP LOGFILE MEMBER 'D:\REDO01.LOG';
statement to resolve the corrupted online redo log file is incorrect. Oracle does not allow you to drop an online
redo log member that belongs to an active or current redo group. Therefore, if you attempt to drop such a
member, you will receive the following error:
ORA-00361: cannot remove last log member 'D:\redo01.log for group 1'