After a number of days set by the parameter CONTROL_FILE_RECORD_KEEP_TIME， the information in the control file is overwritten by RMAN. What is this parameter’s default value？（）

单项选择题WhichofthefollowingstepsisincorrectinthefollowingsequenceofenablingtheARCHIVELOGmodeofadatabase？（）

A.Shut down the database.
B.Set the appropriate parameters in init.ora file.
C.Start the database in NOMOUNT state.
D.Issue the ALTER DATABASE ARCHIVELOG command.
E.Open the database.
F.Take a full closed backup.

单项选择题WhatisthemaximumdatabaseblocksizesupportedfortheOracle9idatabase？（）

A.16KB
B.32KB
C.64KB
D.128KB