OCP: Oracle9i DBA Fundamentals II Study Guide
Review Questions
1. Which type of backup most closely represents an opened backup? (Choose all that apply.)
A. Online backup
B. Offline backup
C. Hot backup
D. Cold backup
----
An opened backup is performed when the database is opened or available for access (online). A hot backup and online backup are synonymous.
Ans: A, C
2. In the event of a database failure that requires a full database restore, how would you perform a recovery for a read-only tablespace? (Choose all that apply.)
A. No recovery is necessary, if the restored copy was made when the tablespace was read-only.
B. You would recover by applying redo log entries to the read-only tablespace, regardless of the state of the tablespace copy.
C. You would recover by applying redo log entries to the read-only tablespace if the tablespace was in read-write mode at the time of the backup used for the restore.
D. You would recover by applying redo log entries to the read-only tablespace if the tablespace was in read-only mode at the time of the backup used for the restore.
---
In a read-only tablespace, the SCN doesn’t change or if it does, none of the changes get applied. So if the backup of the tablespace was taken when the tablespace was read-only, no recovery would be necessary. On the other hand, if the backup was taken when the database was read-write, then redo logs would need to be applied. The redo logs in this case would also contain the command that puts the tablespace into read-only mode.
Ans: A, C.
3. What type of backup is consistent?
A. Online backup
B. Opened backup
C. Hot backup
D. Cold backup
----
A cold backup ensures that all the SCNs in the data files are consistent for a single point in time.
Ans: D.
4. What type of backup is inconsistent? (Choose all that apply.)
A. Cold backup
B. Online backup
C. Opened backup
D. Closed backup
---
Opened and online backups both back up the data files with different SCNs in the headers, which makes recovery necessary during a restore operation.
Ans: B, C.
5. If a read-only tablespace is restored from a backup when the data file is read-only, what type of recovery is necessary?
A. Data file recovery
B. Tablespace recovery
C. Database recovery
D. No recovery is needed.
-----
No recovery is needed because the tablespace was read-only during backup and at the time of failure.
Ans: D.
6. What are valid ways to back up a control file while the database is running? (Choose all that apply.)
A. Back up to trace file
B. Back up to binary control file
C. OS copy to tape
D. Back up to restore file
----
Backing up both to a trace file and to a binary control file are valid backups of the control file. The other references are made up.
Ans: A, B.
7. Which of the following statements is true about a user-managed backup?
A. This type of backup is conducted using the RMAN utility.
B. A user-managed backup can be customized using a combination of OS and database commands.
C. A user-managed backup is a new type of backup in Oracle9i.
D. A user-managed backup is one of the backup options within RMAN.
----
A user-managed backup is a customizable backup that uses OS and database commands, and it is usually written in some sort of native scripting language.
Ans B.
8. If a tablespace was backed up shortly after it was made read-only, what would need to be done with archived logs during a recovery of that tablespace?
A. All archived logs would need to be applied.
B. Only the archived logs that were added after the backup would need to be applied.
C. Only the archived logs that were added before the backup would need to be applied.
D. No archived logs would need to be applied.
----
No archived logs would need to be applied because the tablespace was backed up after it was made read-only.
Ans: D.
9. Which of the following is a true statement about a RMAN image copy?
A. It can be backed up to tape or disk.
B. It can be backed up to disk only.
C. It can be backed up to tape only.
D. It can be copied to tape only.
---
An image copy can be backed up only to disk.
Ans B.
10. A cold backup requires the database to be in what condition? (Choose all that apply.)
A. ARCHIVELOG mode
B. NOARCHIVELOG mode
C. The database must be started.
D. The database cannot contain any read-only tablespaces.
---
Ans: A cold backup occurs when the database is shutdown. The database can be in ARCHIVELOG mode or NOARCHIVELOG mode.
11. To perform an open or hot backup, what state must the database be in?
A. ARCHIVELOG mode
B. NOARCHIVELOG mode
C. Shutdown
D. Automatic archiving must be enabled.
----
The database must be in ARCHIVELOG mode. Archiving can be set to manual or automatic.
Ans: A.
12. Hot backups are best run when what is occurring in the database?
A. Heavy DML activity
B. Heavy batch processing
C. The database is being shut down.
D. Low DML activity
----
More transactional activity gets written to redo logs when a tablespace is in backup mode. It is a good idea to do hot backups when you have the lowest transactional activity.
Ans: D.
13. What method can be used to clean up a failed online or hot backup?
A. Shutting down the database
B. Querying V$TABLESPACE
C. Querying V$BACKUP
D. Querying V$DATAFILE
----
It is a good idea to query V$BACKUP to check to see if any data files are being actively backed up. If they are, you can execute ALTER TABLESPACE
Ans: C.
14. What utility can be used to check to see if a data file has block corruption?
A. DBVALIDATE
B. DBVERIFY
C. DBVERIFIED
D. DBVALID
----
The DBVERIFY utility is used to check whether or not a data file has any block corruption.
Ans: B.
15. Which of the following are types of RMAN backups? (Choose all that apply.)
A. Open and closed backups
B. Full and incremental backups
C. Consistent and inconsistent backups
D. Control file backups
-----
Ans: A, B, C. Open and closed, full and incremental, and consistent and inconsistent backups are the different type of RMAN backups.
No comments:
Post a Comment