多项选择题
A.backup of offline tablespaces
B.backup of readonly tablespaces
C.backup of systemcritical tablespaces
D.backup of online， locally managed tablespaces
E.backup of read/write dictionarymanaged tablespaces
多项选择题 View the Exhibit. You executed the following command to perform a backup of the USERS tablespace： RMAN> BACKUP TABLESPACE USERS Which three types of files are backed up？ （）
单项选择题 View the Exhibit. You executed the following command to perform a backup of the USERS tablespace： RMAN> BACKUP TABLESPACE USERS Which type of backup would this command perform？（）
单项选择题 You execute the following command to perform a backup by using Recovery Manager （RMAN）： RMAN> run {allocate channel c1 type sbt backup datafile 1 } The command errors out. A part of the error message is as follows： RMAN03009： failure of allocate command on c1 channel ORA19554： error allocating device， device type： SBT_TAPE， device name： What could explain why the statement failed？（）