Examine the following RMAN command:
RMAN> CONFIGURE ENCRYPTION FOR DATABASE ON;
RMAN> BACKUP DATABASE PLUS ARCHIVELOG;
Which prerequisite must be met before accomplishing the backup?（）

单项选择题After you have restored and recovered a database to a new host by using a previously performed Recovery Manager (RMAN) backup, which is the best option you would consider for the new database?（）

A. Opening the database in RESTRICTED mode
B. Opening the database with the RESETLOGS option
C. Setting a new DBID for the newly restored database
D. Restoring the server parameter file (SPFILE) to the new host

多项选择题User SCOTT wants to back out the transactions on the REGIONS table in his schema. As a DBA, which commands must you execute to enable SCOTT to flash back the transactions?（）

A. ALTER DATABASE FLASHBACK ON;
B. GRANT SELECT any transaction TO scott;
C. GRANT EXECUTE ON dbms_flashback TO scott;
D. ALTER DATABASE ADD SUPPLEMENTAL LOG DATA;
E. ALTER TABLESPACE undots1 RETENTION GUARANTEE;
F. ALTER DATABASE ADD SUPPLEMENTAL LOG DATA (PRIMARY KEY) COLUMNS;

单项选择题Examine the following RMAN script: Which statement describes the purpose of the script?（）

A. The data file is checked for physical corruption and backed up if found clean.
B. The backup of data file 5 is performed and the interactive messages during the backup are suppressed.
C. The existing backup for the data file is checked and the backup is performed if there are changes in the data file after the last backup.
D. The backup of data file 5 is performed and all SQL statements that are executed during RMAN compilation and their results are displayed

单项选择题What does the DB_FLASHBACK_RETENTION_TARGET parameter configure?（）

A. An upper limit on how far you can flash back the database, depending on the information in the redo logs
B. An upper limit on how far you can flash back the database, depending on the information in the undo tablespace
C. The amount of time for which the flashback data is to be kept in the flash recovery area, provided that there is enough space
D. The amount of time for which the flashback data is guaranteed to be kept in the undo tablespace, provided that there is enough space

单项选择题You are working in an online transaction processing (OLTP) environment. You use the FLASHBACKTABLE command to flash back the CUSTOMERS table. Before executing the FLASHBACK TABLE command, the system change number (SCN) was 663571. After flashing back the CUSTOMERS table, you realize that the table is not in the correct state. Now, you need to reverse the effects of the FLASHBACK TABLE command. Which is the fastest and the most efficient option to reverse the effects of the FLASHBACK TABLE command?（）

A. Restore the backup control file and open the database with RESETLOGS option.
B. Perform point-in-time recovery because flashback cannot be performed again on this table
C. Execute the FLASHBACK DATABASE statement to retrieve the CUSTOMERS table as it was at SCN 663571
D. Execute another FLASHBACK TABLE statement to retrieve the CUSTOMERS table as it was at SCN 663571