You decide to enable Flashback Database in your Oracle 10g database so that future recoveries will take less time than traditional recoveries. Which of the following parameters must be included in your initialization parameter file before enabling Flashback Database？（）

单项选择题InwhichscenariowillyouusetheFlashbackVersionQueryfeature？（）

A. when you want to restore a table that has been dropped from the Recycle Bin
B. when you want to identify the transaction ID of the transaction that deleted some important records from a table
C. when you want to recover the schema of a dropped user
D.when you want to restore a dropped tablespace

单项选择题YouareworkingasaDBAatNetFxCorporation.YoudiscoverthattheSCOTTschemaisdeletedbymistake.Youdecidetoflashthedatabasebacktothetimewhentheschemaexisted.Whichviewwillyouquerytodeterminetheestimatedsizeoftheflashbackdatathatyourequireforyourcurrenttargetretention？（）

A. V$FLASHBACK_DATABASE_LOG
B. V$FLASHBACK_DATABASE_STAT
C. V$DATABASE
D. V$UNDOSTAT

单项选择题YouhavejoinedaneworganizationasaDatabaseAdministrator.TheSecurityAdministratorinyourorganizationhaskepthumanerrors，suchaserroneouslydroppingusers，tables，andimportantdata，toaminimumbycarefullygrantingonlythenecessaryprivilegestoeachuser.Asaresultofseveralongoingtransactionswithinyourdatabase，youdiscoverthattheflashbacklogsarerapidlyincreasingintheflashrecoveryarea.Toavoidout-of-spaceerrors，youdecidetodeletetheflashbacklogsfromtheflashrecoveryarea.Howcanyoudeletetheflashbacklogsfromthedatabaseifyourdatabaseisupandrunning？（）

A. Shut down the database using the SHUTDOWN command. Mount the database using the STARTUP MOUNT EXCLUSIVE command and disable Flashback Database using the ALTER DATABASE FLASHBACK OFF statement.
B. Change the parameter setting in the SPFILE for the DB_RECOVERY_FILE_DEST parameter using the ALTER SYSTEM SET DB_RECOVERY_FILE_DEST=’’ SCOPE=BOTH statement while the database is up and running.
C. Shut down the database using the SHUTDOWN command. Mount the database using the STARTUP MOUNT EXCLUSIVE command. Change the parameter setting in the SPFILE for the DB_RECOVERY_FILE_DEST parameter using the ALTER SYSTEM SET DB_RECOVERY_FILE_DEST=’’ SCOPE=BOTH statement. Disable Flashback Database using the ALTER DATABASE FLASHBACK OFF statement.
D. Change the parameter setting in the SPFILE for the DB_RECOVERY_FILE_DEST parameter using the ALTER SYSTEM SET DB_RECOVERY_FILE_DEST=’’ SCOPE=BOTH statement. Shut down the database using the SHUTDOWN command. Mount the database using the STARTUP MOUNT EXCLUSIVE command and disable Flashback Database using the ALTER DATABASE FLASHBACK OFF statement.

单项选择题InwhichscenariodoyouusetheFlashbackDatabasefeature？（）

A. when a table is dropped and you restore it from the Recycle Bin
B. when a user’s schema is dropped and you recover the user’s schema
C. when some incorrect data is inserted in the table and you retrieve the table to a state that was at a certain timestamp
D. when a row of a table is updated frequently and committed， and you view all the versions of the row within a specific duration

单项选择题An important tablespace of your database is dropped by mistake. You use the Flashback Database feature to retrieve the tablespace. You perform the following steps to retrieve the tablespace：   1. You log on to Enterprise Manager as SYSDBA.    2. You select the maintenance screen.    3. You choose Perform Recovery option on the maintenance screen.    4. You choose Whole Database in the Object Type drop-down list Perform Recovery： Type screen. 5. You choose Recover to Current Time from the Operation Type on the Perform Recovery： Type screen.    6. You provide the Host Credentials for a database user. on the Perform Recovery： Type screen.    7. You click the continue button.    An information screen appears saying that the database is unavailable. What is this information screen？（）

A.Recovery Manager
B.Recovery Window
C.Recovery Wizard
D.Enterprise Manager Home Page