A senior DBA asked you to execute the following command to improve performance:
SQL> ALTER TABLE subscribe log STORAGE (BUFFER_POOL recycle);
You checked the data in the SUBSCRIBE_LOG table and found that it is a large table containing one million rows.
What could be a reason for this recommendation?（）

单项选择题You are administering a database and you receive a requirement to apply the following restrictions: 1. A connection must be terminated after four unsuccessful login attempts by user. 2. A user should not be able to create more than four simultaneous sessions. 3. User session must be terminated after 15 minutes of inactivity. 4. Users must be prompted to change their passwords every 15 days. How would you accomplish these requirements?（）

A. by granting a secure application role to the users
B. by creating and assigning a profile to the users and setting the REMOTE_OS_AUTHENT parameter to false
C. By creating and assigning a profile to the users and setting the SEC_MAX_FAILED_LOGIN_ATTEMPTS parameter to 4
D. By Implementing Fine-Grained Auditing (FGA) and setting the REMOTE_LOGIN_PASSWORD_FILE parameter to none.
E. By implementing the database resource Manager plan and setting the SEC_MAX_FAILED_LOGIN_ATTEMPTS parameters to 4.

多项选择题You administer an online transaction processing (OLTP) system whose database is stored in Automatic Storage Management (ASM) and whose disk group use normal redundancy. One of the ASM disks goes offline, and is then dropped because it was not brought online before DISK_REPAIR_TIME elapsed. When the disk is replaced and added back to the disk group, the ensuing rebalance operation is too slow. Which two recommendations should you make to speed up the rebalance operation if this type of failure happens again?（）

A. Increase the value of the ASM_POWER_LIMIT parameter.
B. Set the DISK_REPAIR_TIME disk attribute to a lower value.
C. Specify the statement that adds the disk back to the disk group.
D. Increase the number of ASMB processes.
E. Increase the number of DBWR_IO_SLAVES in the ASM instance.

多项选择题Identify three valid methods of opening, pluggable databases (PDBs).（）

A. ALTER PLUGGABLE DATABASE OPEN ALL ISSUED from the root
B. ALTER PLUGGABLE DATABASE OPEN ALL ISSUED from a pdb
C. ALTER PLUGGABLE DATABASE PDB OPEN issued from the seed
D. ALTER DATABASE PDB OPEN issued from the root
E. ALTER DATABASE OPEN issued from that pdb 
F. ALTER PLUGGABLE DATABASE PDB OPEN issued from another pdb
G. ALTER PLUGGABLE DATABASE OPEN issued from that pdb

多项选择题You executed this command to create a password file: $ orapwd file = orapworcl entries = 10 ignorecase = N Which two statements are true about the password file?（）

A. It will permit the use of uppercase passwords for database users who have been granted the SYSOPER role.
B. It contains username and passwords of database users who are members of the OSOPER operating system group.
C. It contains usernames and passwords of database users who are members of the OSDBA operating system group.
D. It will permit the use of lowercase passwords for database users who have granted the SYSDBA role.
E. It will not permit the use of mixed case passwords for the database users who have been granted the SYSDBA role.

单项选择题To enable the Database Smart Flash Cache, you configure the following parameters: DB_FLASH_CACHE_FILE = ‘ dev flash_device_1’ , ‘ dev flash_device_2’ DB_FLASH_CACHE_SIZE=64G What is the result when you start up the database instance?（）

A. It results in an error because these parameter settings are invalid.
B. One 64G flash cache file will be used.
C. Two 64G flash cache files will be used.
D. Two 32G flash cache files will be used.