Review Questions
1. What are the three types of incomplete recovery? (Choose all that apply.)
A. Change-based
B. Time-based
C. Stop-based
D. Cancel-based
E. Quit-based
Answer: A, B, D
Options A, B, and D all describe valid types of incomplete recovery. Options C and E are not incomplete recovery types.
Chapter: 11
2. Which type of incomplete recovery can be performed in NOARCHIVELOG mode?
A. Change-based
B. Time-based
C. Stop-based
D. Cancel-based
E. None
Answer: E
Incomplete recovery cannot be performed in NOARCHIVELOG mode.
Chapter: 11
3. You're a DBA and you have just performed an incomplete recovery. You neglected to perform a backup following the incomplete recovery. After a couple of hours of use, the database fails again due to the loss of a disk that stores some of your data files. What type of incomplete recovery can you perform?
A. Change-based
B. Stop-based
C. Time-based
D. Cancel-based
E. None
Answer: E
Incomplete recovery cannot be performed unless a new backup is taken after the first failure. All backups prior to an incomplete recovery are invalidated for use with any of the existing data files, control files, or redo logs.
Chapter: 11
4. What does Oracle use to uniquely identify each committed transaction in the log files?
A. Unique transaction ID
B. Static transaction ID
C. System change number
D. Serial change number
E. Transaction change number
Answer: C
The system change number, or SCN, uniquely identifies each committed transaction in the log files.
Chapter: 11
5. What type of recovery is necessary to execute the ALTER DATABASE OPEN RESETLOGS command? (Choose all that apply.)
A. Complete recovery
B. Incomplete recovery
C. Cancel-based recovery
D. Time-based recovery
Answer: B, C, D
All forms of incomplete recovery require the use of the RESETLOGS clause during the ALTER DATABASE OPEN command. All redo logs must be reset to a new sequence number. This invalidates all prior logs to that database.
Chapter: 11
6. What should be performed after the ALTER DATABASE OPEN RESETLOGS command has been applied?
A. A recovery of the database
B. A backup of the database
C. An import of the database
D. Nothing
Answer: B
A backup of the database should be performed if the ALTER DATABASE OPEN RESETLOGS command has been applied.
Chapter: 11
7. What type of incomplete recovery gives the DBA the most control?
A. Cancel-based
B. Time-based
C. Change-based
D. All give equal control.
Answer: C
Change-based recovery gives the DBA the most control of the incomplete recovery process because it allows the stopping point to be specified by the SCN number.
Chapter: 11
8. Which type of incomplete recovery gives the DBA the least control?
A. Cancel-based
B. Time-based
C. Change-based
D. All give equal control.
Answer: A
Cancel-based recovery applies the complete archived log before it cancels or stops the recovery process. Therefore, you cannot recover part of the transactions within the archived log as with change-based or time-based recovery.
Chapter: 11
9. What command is used in an RMAN incomplete recovery?
A. SET SEQUENCE
B. SET UNTIL TIME
C. SET TIME
D. SET CHANGE
Answer: B
RMAN time-based recovery applies the changes in an archived log up to the point in time reference specified in the SET UNTIL TIME command.
Chapter: 11
10. A reset command should be performed after what action in the database?
A. The database is opened with the RESETLOGS option.
B. There is a physical change to the recovery catalog.
C. There is a physical change to the target database.
D. The database has been completely recovered.
Answer: A
Anytime the database is opened with the RESETLOGS options, you will need to reset the target database in the recovery catalog.
Chapter: 11
11. The RMAN change-based recovery has which of the following options? (Choose all that apply.)
A. LOGSEQ
B. SEQLOG
C. SEQUENCE
D. SCN
Answer: A, C, D
There are three RMAN change options: LOGSEQ, SEQUENCE, and SCN. These are used with the SET UNTIL command.
Chapter: 11
12. If you need to perform a user-managed recovery of a database and you stop the recovery before October 4th at 15:01:00, which command would be used?
A. SET UNTIL TIME `OCT 04 2001 15:00:00'
B. RECOVER UNTIL TIME `OCT 04 2001 15:00:00'
C. RECOVER DATABASE UNTIL TIME `OCT 04 2001 15:00:00'
D. RECOVER TABLESPACE UNTIL TIME `OCT 04 2001 15:00:00'
Answer: C
The user-managed recovery of a database would be performed with the RECOVER DATABASE UNTIL TIME `OCT 04 2001 15:00:00' command.
Chapter: 11
13. Which of the following situations will force an incomplete recovery?
A. Loss of data file
B. Corrupt data file
C. Loss of an online redo log that has been archived
D. Corrupt current online redo log
Answer: D
A corrupt current online redo will force an incomplete recovery because the transactions in that log will not be applied to the recovery process, and the database will need to be stopped before complete recovery by time, change, or cancel commands.
Chapter: 11
14. Which of the following is a common command that must be performed with all incomplete recoveries and not with complete recoveries?
A. RECOVER DATABASE
B. RECOVER UNTIL CANCEL
C. ALTER DATABASE OPEN RESETLOGS
D. RESTORE DATABASE
Answer: C
The ALTER DATABASE OPEN RESETLOGS command must be performed with all incomplete recoveries but it does not have to be performed with complete recoveries.
Chapter: 11
15. What information could be required in order for a change recovery to be performed? (Choose all that apply.)
A. SEQUENCE#
B. FIRST_CHANGE#
C. NEXT_CHANGE#
D. Information from V$LOG_HISTORY
E. All of the above
Answer: E
All options are information from the V$LOG_HISTORY view, which contain the log sequence number and SCN information.
Chapter: 11
1. What are the three types of incomplete recovery? (Choose all that apply.)
A. Change-based
B. Time-based
C. Stop-based
D. Cancel-based
E. Quit-based
Answer: A, B, D
Options A, B, and D all describe valid types of incomplete recovery. Options C and E are not incomplete recovery types.
Chapter: 11
2. Which type of incomplete recovery can be performed in NOARCHIVELOG mode?
A. Change-based
B. Time-based
C. Stop-based
D. Cancel-based
E. None
Answer: E
Incomplete recovery cannot be performed in NOARCHIVELOG mode.
Chapter: 11
3. You're a DBA and you have just performed an incomplete recovery. You neglected to perform a backup following the incomplete recovery. After a couple of hours of use, the database fails again due to the loss of a disk that stores some of your data files. What type of incomplete recovery can you perform?
A. Change-based
B. Stop-based
C. Time-based
D. Cancel-based
E. None
Answer: E
Incomplete recovery cannot be performed unless a new backup is taken after the first failure. All backups prior to an incomplete recovery are invalidated for use with any of the existing data files, control files, or redo logs.
Chapter: 11
4. What does Oracle use to uniquely identify each committed transaction in the log files?
A. Unique transaction ID
B. Static transaction ID
C. System change number
D. Serial change number
E. Transaction change number
Answer: C
The system change number, or SCN, uniquely identifies each committed transaction in the log files.
Chapter: 11
5. What type of recovery is necessary to execute the ALTER DATABASE OPEN RESETLOGS command? (Choose all that apply.)
A. Complete recovery
B. Incomplete recovery
C. Cancel-based recovery
D. Time-based recovery
Answer: B, C, D
All forms of incomplete recovery require the use of the RESETLOGS clause during the ALTER DATABASE OPEN command. All redo logs must be reset to a new sequence number. This invalidates all prior logs to that database.
Chapter: 11
6. What should be performed after the ALTER DATABASE OPEN RESETLOGS command has been applied?
A. A recovery of the database
B. A backup of the database
C. An import of the database
D. Nothing
Answer: B
A backup of the database should be performed if the ALTER DATABASE OPEN RESETLOGS command has been applied.
Chapter: 11
7. What type of incomplete recovery gives the DBA the most control?
A. Cancel-based
B. Time-based
C. Change-based
D. All give equal control.
Answer: C
Change-based recovery gives the DBA the most control of the incomplete recovery process because it allows the stopping point to be specified by the SCN number.
Chapter: 11
8. Which type of incomplete recovery gives the DBA the least control?
A. Cancel-based
B. Time-based
C. Change-based
D. All give equal control.
Answer: A
Cancel-based recovery applies the complete archived log before it cancels or stops the recovery process. Therefore, you cannot recover part of the transactions within the archived log as with change-based or time-based recovery.
Chapter: 11
9. What command is used in an RMAN incomplete recovery?
A. SET SEQUENCE
B. SET UNTIL TIME
C. SET TIME
D. SET CHANGE
Answer: B
RMAN time-based recovery applies the changes in an archived log up to the point in time reference specified in the SET UNTIL TIME command.
Chapter: 11
10. A reset command should be performed after what action in the database?
A. The database is opened with the RESETLOGS option.
B. There is a physical change to the recovery catalog.
C. There is a physical change to the target database.
D. The database has been completely recovered.
Answer: A
Anytime the database is opened with the RESETLOGS options, you will need to reset the target database in the recovery catalog.
Chapter: 11
11. The RMAN change-based recovery has which of the following options? (Choose all that apply.)
A. LOGSEQ
B. SEQLOG
C. SEQUENCE
D. SCN
Answer: A, C, D
There are three RMAN change options: LOGSEQ, SEQUENCE, and SCN. These are used with the SET UNTIL command.
Chapter: 11
12. If you need to perform a user-managed recovery of a database and you stop the recovery before October 4th at 15:01:00, which command would be used?
A. SET UNTIL TIME `OCT 04 2001 15:00:00'
B. RECOVER UNTIL TIME `OCT 04 2001 15:00:00'
C. RECOVER DATABASE UNTIL TIME `OCT 04 2001 15:00:00'
D. RECOVER TABLESPACE UNTIL TIME `OCT 04 2001 15:00:00'
Answer: C
The user-managed recovery of a database would be performed with the RECOVER DATABASE UNTIL TIME `OCT 04 2001 15:00:00' command.
Chapter: 11
13. Which of the following situations will force an incomplete recovery?
A. Loss of data file
B. Corrupt data file
C. Loss of an online redo log that has been archived
D. Corrupt current online redo log
Answer: D
A corrupt current online redo will force an incomplete recovery because the transactions in that log will not be applied to the recovery process, and the database will need to be stopped before complete recovery by time, change, or cancel commands.
Chapter: 11
14. Which of the following is a common command that must be performed with all incomplete recoveries and not with complete recoveries?
A. RECOVER DATABASE
B. RECOVER UNTIL CANCEL
C. ALTER DATABASE OPEN RESETLOGS
D. RESTORE DATABASE
Answer: C
The ALTER DATABASE OPEN RESETLOGS command must be performed with all incomplete recoveries but it does not have to be performed with complete recoveries.
Chapter: 11
15. What information could be required in order for a change recovery to be performed? (Choose all that apply.)
A. SEQUENCE#
B. FIRST_CHANGE#
C. NEXT_CHANGE#
D. Information from V$LOG_HISTORY
E. All of the above
Answer: E
All options are information from the V$LOG_HISTORY view, which contain the log sequence number and SCN information.
Chapter: 11
