Get Familiar With Oracle Database 11g: Administration II

  By Certification Magazine —

A Self Test Software Practice Test

These questions are based on 1Z0-053: Oracle Database 11g: Administration.

Objective: Database architecture and ASM.
Sub-objective: Describe automatic storage management (ASM).

Single answer, multiple-choice

Which task does the RBAL process perform?

A.    Coordinates rebalancing activity for disk groups.
B.    Performs the actual extent rebalancing.
C.    Issues alerts when specific metric thresholds are exceeded.
D.    Automatically manages failures involving distributed transactions.

Answer:
A. Coordinates rebalancing activity for disk groups.

Tutorial:
The RBAL process coordinates rebalancing activity for disk groups.

The ARBn processes perform the actual extent rebalancing in an automatic storage management (ASM) instance.

The MMON process issues alerts when specific metric thresholds are exceeded.

The RECO process automatically manages failures involving distributed transactions.

References:
Oracle University - Oracle Database 11g: Administration Workshop II - Chapter 1: Database Architecture and ASM - ASM: General Architecture
D50079GC10
Edition 1.0
November 2007
D53298

Oracle Database Storage Administrator's Guide 11g Release 1 (11.1), Part Number B31107-04, Administering ASM Instances - Administering ASM Instances - ASM Background Processes

Objective: Perform user-managed backup and recovery.
Sub-objective: Perform user-managed incomplete database recovery.

Single answer, multiple-choice

Your database is running in ARCHIVELOG mode, and you are using password authentication. You make user-managed complete consistent backups each night. With your current backup strategy, which statement is true?

A.    If all archived redo log files since the last nightly backup are not available, only incomplete recovery would be possible.
B.    Incomplete recovery would be required if a user accidentally dropped a tablespace.
C.    If you lose a datafile in a SYSTEM tablespace, you must perform incomplete recovery.
D.    If your password file is lost, incomplete recovery must be performed to restore it.

Answer:
A. If all archived redo log files since the last nightly backup are not available, only incomplete recovery would be possible.

Tutorial:
If all archived redo log files since the last nightly backup are not available, only incomplete recovery would be possible. A complete database recovery restores the database completely, including all committed data, with no data loss. To perform a complete recovery, you must have a current control file, the latest backup and the necessary redo to apply the redo since the last backup. If any of these are not available, complete recovery is not possible.

If all of the archived redo log files since the last nightly backup are not available, you would not be able to apply all the necessary redo to recover the database completely. Only incomplete recovery would be possible, and you would incur some data loss.

When performing incomplete recovery, you can perform time-based recovery using the UNTIL TIME clause of the RECOVER command to recover the database up to a particular time, or you can perform changed-based recovery using the UNTIL CHANGE clause to recover the database up to a specified SCN. You also can perform cancel-based recovery. With cancel-based recovery, you are prompted for each redo log file to either apply the redo or cancel the recovery.

After performing incomplete recovery, you should open the database with the RESETLOGS options. When you open the database with the RESETLOGS option, the datafiles are synchronized with the control files and redo logs.

The option that states incomplete recovery would be required if a user accidentally dropped a tablespace is incorrect. You can use tablespace point-in-time recovery to recover a tablespace that is accidentally deleted.

The option that states if you lose a datafile in a SYSTEM tablespace, you must perform incomplete recovery is incorrect. You can perform complete recovery if you have a current control file, the latest backup that contains the lost datafile and the needed archived redo log files to apply the redo since the last datafile backup. However, you should note that to perform complete recovery of a datafile in a SYSTEM tablespace, the database must be closed.

The option that states if your password file is lost, incomplete recovery must be performed to restore it is incorrect. To recover from a lost password file, you only need to re-create the password file using the orapwd utility.

References:
Oracle University - Oracle Database 11g: Administration Workshop II - Chapter 6: Performing User-Managed Backup and Recovery - Comparing Complete and Incomplete Recovery
D50079GC10
Edition 1.0
November 2007
D53298

Oracle University - Oracle Database 11g: Administration Workshop II - Chapter 6: Performing User-Managed Backup and Recovery - Incomplete Recovery Process
D50079GC10
Edition 1.0
November 2007
D53298

Oracle Database Concepts 11g Release 1 (11.1), Part Number B28318-03 Backup and Recovery - Data Repair - Media Recovery - Database Point-in-Time Recovery

Oracle Database Backup and Recovery User's Guide 11g Release 1 (11.1), Part Number B28270-02, Performing User-Managed Database Flashback and Recovery - Performing Incomplete Database Recovery
 

Objective: Use RMAN to perform recovery.
Sub-objective: Perform incomplete recovery using RMAN.

Multiple answer, multiple-choice

You perform a full user-managed backup every Sunday at 8 p.m. Your database is running in ARCHIVELOG mode. On Monday, at 9 a.m., a tablespace is dropped. You decide to perform user-managed incomplete recovery to recover the dropped tablespace.

From the SQL prompt, which two clauses can you use with the RECOVER command? (Choose two.)

A.    UNTIL SEQUENCE.
B.    UNTIL SCN.
C.    UNTIL CHANGE.
D.    UNTIL CANCEL.

Answer:
C. UNTIL CHANGE.
D. UNTIL CANCEL.

Tutorial:
You can use either the UNTIL CHANGE or the UNTIL CANCEL clause with the RECOVER statement at the SQL prompt to perform a user-managed recovery. The UNTIL CANCEL clause specifies that Oracle will stop the recovery process when the administrator performing the recovery issues the CANCEL command. The UNTIL CHANGE clause specifies an SCN number immediately after the last SCN number you want to recover. For example, if you want to restore up to SCN 12, you would include the UNTIL CHANGE 13 clause in your RECOVER command.

The option stating that you can use the UNTIL SEQUENCE clause with the RECOVER command at the SQL prompt to perform a user-managed recovery is incorrect. The UNTIL SEQUENCE clause works with only the RMAN utility. The UNTIL SEQUENCE clause specifies that RMAN will stop the recovery operation at the sequence number immediately preceding the specified sequence number.

The option stating that you can use the UNTIL SCN clause with the RECOVER command at the SQL prompt to perform the user-managed recovery is incorrect. The UNTIL SCN clause works with only the RMAN utility. The UNTIL SCN clause specifies that RMAN will stop the recovery operation at the SCN immediately preceding the specified SCN.

References:
Oracle University - Oracle Database 11g: Administration Workshop II - Chapter 6: Performing User-Managed Backup and Recovery - Performing User-Managed Incomplete Recovery
D50079GC10
Edition 1.0
November 2007
D53298