READ Free Dumps For Oracle- 1z0-023
| Question ID 8829 | A DBA enters the command: ALTER DATABASE ADD LOGFILE MEMBER '/w01/oracle/DBA/log1b.rdo' TO GROUP 1, '/w02/oracle/DBA/log2b.rdo' TO GROUP 2; How does Oracle size the new redo logs?
|
| Option A | It sizes them at five times the database block size
|
| Option B | It uses the size of the current members in group 1 and group 2.
|
| Option C | It uses the default size specified during the CREATE DATABASE command.
|
| Option D | It uses the size of the files log1b.rdo and log2b.rdo that already exists.
|
| Correct Answer | B |
Explanation Explanation/Reference: Explanation: Answer B is correct. Oracle will size new member in the group 1 as all other members in this group and new member in the group 2 as existing member. Incorrect Answers: A: Redo log member does not have to be exactly at 5 times the database block size. This restriction works for minimal extent size. C: Redo log member does not use the default size specified during the CREATE DATABASE command, because members in different redo groups can have different size. Just all members in one group must have the same size. D: Redo logs do not use existing size of files log1b.rdo and log2b.rdo. Oracle 8, DBA Certification Exam Guide, Jason S. Couchman, p. 330-332 Chapter 7: Managing the Physical Database Structure
| Question ID 8830 | Which SQL command forces a log switch and causes a checkpoint to occur?
|
| Option A | ALTER SYSTEM CHECKPOINT
|
| Option B | ALTER DATABASE CHECKPOINT
|
| Option C | ALTER SYSTEM SWITCH LOGFILE
|
| Option D | ALTER DATABASE SWITCH LOGFILE
|
| Correct Answer | C |
Explanation Explanation/Reference: Explanation: Answer C is correct. A log switch is the point at which LGWR fills one online redo log group with information. At every log switch, a checkpoint occurs. A checkpoint (CKPT) is when LGWR DBWR to write all changes made to data blocks in memory to disk, and DBWR does it. ALTER SYSTEM SWITCH LOGFILE command forces a log switch and causes a checkpoint to occur. Incorrect Answers: A: There is no ALTER SYSTEM CHECKPOINT command in Oracle. C: There is no ALTER DATABASE CHECKPOINT command in Oracle. D: There is no ALTER DATABASE SWITCH LOGFILE command in Oracle. Oracle 8, DBA Certification Exam Guide, Jason S. Couchman, p. 328-330 Chapter 7: Managing the Physical Database Structure