单项选择题
A. You must use automatic undo management in the database.
B. You must configure OMF in your database.
C. You must configure ASM for storing the datafiles.
D. You must multiplex the online redo log file.
单项选择题 At 5：30 PM， a database administrator， William， is informed that an important record of employee no E0025 is missing from the SCOTT.EMPLOYEE table. At 4：30 P.M， the table contained the record of employee no E0025. William issues the following command to find the SQL statements that are used to undo the deletion： SELECT operation， undo_sql， logon_user FROM FLASHBACK_TRANSACTION_QUERY WHERE xid= HEXTORAW（’0100043E23456’）； where ’0100043E23456’ is the transaction ID of the transaction that deleted the row. Before issuing the above statement， which task did William perform to identify the transaction ID of the transaction that deleted the row？（）
单项选择题 YouareemployedasaDBAinanorganization.YouareinformedthattherecordofEMP_NO1000ismissingfromtheSCOTT.EMPtable.Youarerequiredtoidentifytheuserwhodeletedtherecord，theSQLstatementthatwillundothedeletion，andthetransactionIDofthetransactionthatdeletedtheemployeerecord.Whichfeaturewillyouusetoperformthetasks？（）
单项选择题 InwhichscenariowillyouusetheFlashbackTransactionQueryfeature？（）