You are using the Block Media Recovery feature to recover the blocks that are marked corrupt since the last backup. Which view will you query to display information about the data blocks that are marked corrupt since the last backup？（）

单项选择题YouaremaintainingyourOLTPdatabaseinOracle10g.YouareperformingtheFlashbackTransactionQuerytofindtheundoSQLstatementsthatcanbeusedtoundothechangesmadetothedatabaseinthespecifictimeperiod.WhichpseudocolumnwillyouusetoperformtheFlashbackTransactionQuery？（）

A. VERSIONS_STARTSCN
B. VERSIONS_STARTTIME
C. VERSIONS_XID
D. VERSIONS_OPERATION

单项选择题WhatwillbetheresultofusingtheSQL>DROPUSERSCOTTCASCADE；command？（）

A. The user， Scott， is dropped， all the objects in Scott’s schema are placed in the Recycle Bin， and the objects that are  already in the Recycle Bin are dropped.
B. The user， Scott， is dropped， all the objects in Scott’s schema are placed in the Recycle Bin， and all the objects in the Recycle Bin， belonging to the user Scott， are not dropped.
C. The user， Scott， is dropped， all the objects in the Scott’s schema are not placed in the Recycle Bin， and the objects in the Recycle Bin， belonging to the user， Scott， are not dropped.
D. The user， Scott， is dropped， all the objects in Scott’s schema are not placed in the Recycle Bin， and the objects in the Recycle Bin are dropped.

单项选择题You are performing flashback of the ORDERS table in the Scott’s schema because some important data is deleted in the table by mistake. The SCN number was 771513 at the time of deletion. You issued the following statement to perform Flashback Table：  SQL> FLASHBACK TABLE ORDERS TO SCN 771513；   What is the prerequisite to perform Flashback Table？（）

A. You must configure OMF in your database.
B. You must enable block change tracking feature in your database.
C. You must enable ROW MOVEMENT feature on the ORDERS table.
D. You must use the Flashback Version Query before using the Flashback Table feature.

单项选择题You are working as a DBA at NetFx Corporation. A user， Scott， is maintaining the records of all the employees in the EMPLOYEEtable. Initially， the salary of the employee， ’E0025’， was $1800. On 1 May 2004， the salary of the employee， ’E0025’， was increased by $200.   The user， Scott， issued the following statement to modify the record of the employee， ’E0025’：   SQL>UPDATE EMPLOYEE  SET SALARY = 2000   WHERE EMPNO = ’E0025’；   SQL>COMMIT；   On December 1， 2004， the salary of the employee， ’E0025’， was increased by $400. The user， Scott， issued the following statement to modify the record of the employee， ’E0025’：   SQL>UPDATE EMPLOYEE  SET SALARY = 2400   WHERE EMPNO = ’E0025’；   SQL>COMMIT；   On July 1， 2005， the salary of the employee， ’E0025’， was increased by $500. The user， Scott， issued the following statement to modify the record of the employee， ’E0025’   SQL>UPDATE EMPLOYEE  SET SALARY = 2900   WHERE EMPNO = ’E0025’；   SQL>COMMIT；   On July 5， 2005， the HR manager asked you to generate the increment report of the employee， ’E0025’， for the period between 1 May 2004 and 1 July 2005. Which flashback feature will you use to generate the increment report？（）

A. Flashback Drop
B. Flashback Table
C. Flashback Database
D.Flashback Version Query

单项选择题Attheendofthefinancialyear，anaccountsaccumulationbatchisrun.Thisbatchupdatesthecompany’saccountingrecords.Duringthebatchrunprocess，someincorrectentrieswereinsertedintotheACCOUNTtable.Youidentifiedthebugandimmediatelystoppedthebatchrunprocess，but3000incorrectrecordswereinsertedintotheACCOUNTtablebeforethebatchprocesswasstopped.Youwanttorecoverthetabletothestateitwasat11：50P.M.Whichflashbackfeaturewillyouuse？（）

A. Flashback Drop
B. Flashback Database
C. Flashback Table
D. Flashback Version Query