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Recovery Through Control File in Oracle - Quiz

This quiz discusses 1) recovery without current redo logs and 2) recovery through the control file Each question is worth one point. Select the best answer or answers for each question.
1. Which statements about choosing a control file recovery method are correct in Oracle AI Database 26ai?
Please select all the correct answers.
  A. If a valid multiplexed copy of the current control file survives, it can be used to repair the control file configuration without restoring an older control file.
  B. Restoring a backup control file supplies the redo records from any damaged or missing archived redo logs.
  C. If all current control file copies are lost or unusable, restoring an available backup control file is a supported recovery path.
  D. Dropping a table or tablespace always requires replacing the current control file of the target database with an older backup.

2. Which statements describe whole-CDB recovery after a backup control file has been restored and mounted?
Please select all the correct answers.
  A. Recovery is required even if no datafiles have been restored.
  B. After successful recovery using the restored backup control file, the CDB must be opened with RESETLOGS.
  C. Complete recovery can still be possible when suitable datafiles and all required redo are available.
  D. Before recovery can begin, you must back up the current control file even when all current copies have been lost.

3. Which statements about the loss of online redo log members are correct?
Please select all the correct answers.
  A. Losing one member of a multiplexed redo log group automatically places the database in restricted mode.
  B. LGWR can continue writing when at least one usable member of the group remains available.
  C. If all members of the current group become inaccessible while LGWR is writing to them, the database instance fails.
  D. An unresponsive or "hung" database is proof that the database is open.

4. A database is unresponsive and a current redo log problem is suspected. Which actions are appropriate before selecting a repair or recovery procedure?
Please select all the correct answers.
  A. Identify the affected thread, group, sequence, and members using V$LOG, V$LOGFILE, and alert-log or storage errors when the required diagnostic access is available.
  B. Check every member of the affected group and determine whether storage access or another usable copy can preserve the required redo.
  C. Immediately clear the current group with CLEAR UNARCHIVED LOGFILE, because an unresponsive database cannot require incomplete recovery.
  D. Determine whether the missing redo is required for instance or media recovery, and evaluate the available backups, recovery targets, and possible data loss before clearing a group.

5. An ARCHIVELOG CDB has one redo thread, thread 1. Its current control file and SPFILE are usable, but redo sequence 482 is irretrievably lost. Suitable earlier datafile backups and continuous required redo through sequence 481 are available. The CDB is mounted, and whole-CDB point-in-time recovery has been selected with the resulting data loss accepted. Which RMAN approach recovers through sequence 481?
Please select the best answer.
  A. In a RUN block, set UNTIL SEQUENCE 481 THREAD 1 before restoring and recovering the database.
  B. In a RUN block, set UNTIL SEQUENCE 482 THREAD 1 before RESTORE DATABASE and RECOVER DATABASE, then open with RESETLOGS after successful recovery.
  C. Use RECOVER DATABASE UNTIL CANCEL as an RMAN command and cancel when RMAN requests sequence 482.
  D. Restore the missing current online redo log group from its RMAN backup and perform complete recovery.