单项选择题
A. Backing up the control file to trace
B. Copying the existing control file of the database to the backup location during a hot backup
C. Copying the existing control file of the database to the backup location during a cold backup
D. Creating a backup control file
E. Using the create controlfile command
单项选择题 EverySundaytheUnixsystemadministratorhasajobthatexecutesafullbackupoftheentireUnixsystemyourdatabaseison.Isthisbackupusableforbackupandrecoveryofyourdatabase？（）
单项选择题 WhichofthefollowingisavalidwayofputtingatablespacenamedDAVE_TBSintohotbackupmode？（）
单项选择题 Whichcommandwillresultinatracefilebeingcreatedwiththecreatecontrolfilecommandcontainedinit？（）