1Z0-053章节练习(2019.03.21)

单项选择题
What is the advantage of setting the ASM-preferred mirror read for the Stretch cluster configuration？（）
A. It improves resync operations.
B. This feature enables much faster file opens.
C. It improves performance as fewer extent pointers are needed in the shared pool.
D. It improves performance by reading from a copy of an extent closest to the node.
单项选择题
Which statement most accurately describes the implementation of a SQL Access Advisor recommendation?（）
A. SQL Access Advisor recommendations are automatically implemented.
B. Individual SQL Access Advisor recommendations can be scheduled for implementation.
C. All SQL Access Advisor recommendations for a specific task must be implemented at the same time.
D. SQL Access Advisor recommendations are automatically scheduled for implementation during the maintenance window.
E. None of the above.
单项选择题
Which are the correct steps， in order， to deal with the loss of an online redo log if the database has not yet crashed？（） a. Issue a checkpoint. b. Shut down the database. c. Issue an alter database open command to open the database. d. Startup mount the database. e. Issue an alter database clear logfile command. f. Recover all database datafiles.
A.a， b， c， d
B.b， d， e， c
C.a， b， d， e， c
D.b， f， d， f， c
E.b， d， a， c
多项选择题
Which two statements are true with respect to the maintenance window？（） .
A. A DBA can enable or disable an individual task in all maintenance windows.
B. A DBA cannot change the duration of the maintenance window after it is created.
C. In case of a long maintenance window，all Automated Maintenance Tasks are restarted every four hours.
D. A DBA can control the percentage of the resource allocated to the Automated Maintenance Tasks in each window
单项选择题
You want to use the automatic management of backup and recovery operations features for your database. Which configuration must you set？（）
A. Enable the flash recovery area and specify it as the archived redo log destination.
B. Disable the flash recovery area and start the database instance in ARCHIVELOG mode.
C. Enable the flash recovery area but do not specify it as the archived redo log destination.
D. Disable the flash recovery area and start the database instance in NOARCHIVELOG mode.
单项选择题
Which of the following is a potential performance tuning recommendation from the SQL Access Advisor?（）
A. Create new indexes.
B. Modify existing indexes.
C. Implement partitioning on a nonpartitioned table.
D. Create materialized views.
E. All of the above
单项选择题
Which option is best practice for creating a recovery catalog owner in the catalog database？（）
A. Granting UNLIMITED QUOTA on the SYSTEM tablespace to the owner
B. Allocating the SYSTEM tablespace as the default tablespace and granting the SYSDBA privilege to the user
C. Creating a new tablespace，allocating this as the default， and granting UNLIMITED QUOTA on this tablespace to the user
D. Allocating the SYSAUX tablespace as the default tablespace and granting UNLIMITED QUOTA on this tablespace to the user
单项选择题
The database is currently open and the temp03.dbf tempfile belonging to the default temporarytablespace TEMP has been corrupted. What steps should you take to recover from this tempfile loss in an efficient manner？（）
A. Allow the database to continue running，drop the TEMP tablespace，and then re-create it with new tempfiles
B. Shut down the database， restore and recover the tempfile from backup，and then open the database with RESETLOGS
C. Allow the database to continue running，take the TEMP tablespace offline，drop the missing tempfile，and then create a new tempfile
D. Allow the database to continue running，add a new tempfile to TEMP tablespace with a new name，and drop the tempfile that has been corrupted
单项选择题
What is the default AU size of an ASM disk group? What is the maximum AU size in an ASM disk group?（）
A. 100KB default, 10TB maximum
B. 256KB default, 1024MB maximum
C. 10MB default, 126PB maximum
D. 64KB default, 1EB maximum
E. 1MB default, 64MB maximum
单项选择题
You want to track and store all transactional changes to a table over its lifetime. To accomplish this task， you enabled Flashback Data Archive with the retention of 5 years. After some time， the business requirement changed and you were asked to change the retention from 5 years to 3 years. To accomplish this， you issued the following command： ALTER FLASHBACK ARCHIVE fla1 MODIFY RETENTION 3 YEAR； What is the implication of this command？（）
A. The command produces an error because the retention time cannot be reduced.
B. All historical data is retained but the subsequent flashback data archives are maintained for only three years.
C. All historical data is purged and the new flashback data archives are maintained for three years.
D. All historical data older than three years is purged from the flashback archive FLA1.