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- OCA Oracle 12C Administration(1Z0-062)
71.
Among the failure events, which is the most serious and may cause data loss?
- A.The loss of an entire redo log-file group but no loss in any other group
- B.A tablespace can hold the objects of only one schema
- C.The loss of one member of each redo log-file group
- D.The failure of the LGWR background process
- Answer & Explanation
- Report
Answer : [A]
Explanation :
Explanation :
| Losing an entire redo log-file group can result in losing committed transactions that may not yet have been written to the database files. Losing all members of a redo log- file group except for one does not affect database operation and does not result in data loss. A message is placed in the alert log file. The failure of LGWR causes an instance failure, but you do not lose any committed transaction data. When an ARCn process fails or is manually terminated, Oracle spawns another one. |
72.
When the database is in ARCHIVELOG mode, database recovery is possible up to which
event or time?
- A.The last redo log file switch
- B.The last checkpoint position
- C.The last commit
- D.The last incremental backup using RMAN
- Answer & Explanation
- Report
Answer : [C]
Explanation :
Explanation :
| In ARCHIVELOG mode, recovering the database is possible up to the last COMMIT state- ment; in other words, no committed transactions are lost in ARCHIVELOG mode. |
73.
Which is a true statement regarding image copies and backup sets.
- A.An image copy stores one data file per image copy, and a backup set can store many data files in a single file.
- B.An image copy stores one data file per image copy, and a backup set consists of one file per data file backed up.
- C.Both image copies and backup sets use a single file to store all objects to be backed up.
- D.A backup set stores each data file in its own backup file, but an image copy places all data files into a single output file.
- Answer & Explanation
- Report
Answer : [A]
Explanation :
Explanation :
| Image copies are duplicate data and log files in OS format. Backup sets are binary compressed files in Oracle proprietary format. In addition to storing multiple data files in a single output file, backup sets do not contain unused blocks. |
74.
Which of the following is not a step in configuring your database to archive redo
log files?
- A.Place the database in ARCHIVELOG mode.
- B.Multiplex the online redo log files.
- C.Specify a destination for archived redo log files.
- D.Specify a naming convention for your archived redo log files.
- Answer & Explanation
- Report
Answer : [B]
Explanation :
Explanation :
| Although it is recommended that you multiplex your online redo log files, it is not required to enable ARCHIVELOG mode of the database. |
75.
Why are online backups known as inconsistent backups?
- A.Because not all control files are synchronized to the same SCN until the database is shut down
- B.Because both committed and uncommitted transactions are included in a backup when the database is online
- C.Because a database failure while an online backup is in progress can leave the database in an inconsistent state
- D.Because online backups make copies of data files while they are not consistent with the control file
- Answer & Explanation
- Report
Answer : [D]
Explanation :
Explanation :
| During an online backup, even if all data files are backed up at the same time, they are rarely, if ever, in sync with the control file. |
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