Flashback Database is enabled in your Oracle 10g database. One of your database users erroneously purged an important table residing in his schema. The table was purged sometime between 10：00 P.M. and 10：30 P.M. The next day， you decide to flash back the database. Before you flash back the database， you want to ensure that you have all the necessary flashback data. Which dynamic performance view must you use to determine whether you have the required flashback data to recover the purged table？（）

单项选择题You are working as a DBA on Oracle Database 9i. You plan to upgrade your 9i database to Oracle 10g. To be familiar with the new database technology， you decide to install Oracle Database 10g on your workstation at home. You create a general purpose database.   After the installation， you make the following changes in your initialization parameter file：LOG_ARCHIVE_DEST_1=’LOCATION=USE_DB_RECOVERY_FILE_DEST’   DB_RECOVERY_FILE_DEST =    ’LOCATION=d： product 10.1.0 flash_recovery_area’  DB_RECOVERY_FILE_DEST_SIZE=10g   Where are the archived redo logs stored for your database？（）

A. The archived redo logs are stored in an operating system-dependent location.
B. The archived redo logs are stored in the location specified by LOG_ARCHIVE_DEST_1.
C. The archived redo logs are stored in the location specified by DB_RECOVERY_FILE_DEST.
D. The archived redo logs are stored in the locations specified by both LOG_ARCHIVE_DEST_1 and  DB_RECOVERY_FILE_DEST.

单项选择题Youhaveconfiguredtheflashrecoveryareatostoreonlineredologfiles，controlfiles，archivedredologsandRMANbackups.Whichofthefollowingfilescanyousuccessfullydeletefromtheflashrecoveryareaifyouwanttoreclaimthespacewithinit？（）

A. multiplexed control files
B. RMAN obsolete backups
C. multiplexed online redo log files
D. archived redo logs that have not been copied to tape

单项选择题Your Oracle Database 10g is online when you execute the following statement：        SQL>ALTER TABLESPACE MY_TABLESPACE FLASHBACK OFF；   What is the result of executing this statement if the Flashback Database feature is already enabled in the database？（）

A. The database does not record flashback logs for MY_TABLESPACE
B. The tables residing in MY_TABLESPACE are not protected by the Recycle Bin.
C. All the tablespaces except MY_TABLESPACE can be recovered using Flashback Database feature.
D. None of the flashback technologies， such as Flashback Table， Flashback Transaction Query and Flashback Version Query can be used to recover individual rows within the objects from MY_TABLESPACE

单项选择题At10：30A.M.，youranabatchjobbymistake，whichexecutedatransactioninthedatabase.Thetransactionidentifierofthetransactionthatmadetothechangesinthedatabaseis0500A00627B000.At11：10A.M.，youstoppedthebatchjob.Now，youwanttoidentifythechangesmadetothedatabasetablesbythebatchjob.Whichviewwillyouquery？（）

A. DBA_PENDING_TRANSACTIONS
B. DBA_AUDIT_STATEMENT
C. V$FLASHBACK_DATABASE_STATS
D. FLASHBACK_TRANSACTION_QUERY

多项选择题YouaremaintainingadatabasethatisinARCHIVELOGmode.Youhaveconfiguredtheflashrecoveryareainyourdatabase.ThedatabaseisinMOUNTEXCLUSIVEmode，andyouwanttoconfiguretheFlashbackDatabasefeature.WhichtwooptionsareNOTrequiredtoconfiguretheFlashbackDatabasefeature？（）

A. Open the database in read-only mode.
B. Set the retention target with the DB_FLASHBACK_RETENTION_TARGET initialization parameter.
C. Enable the block change tracking feature.
D. Execute the ALTER DATABASE FLASHBACK ON statement.