为自己加油

Examine the RMAN command:

RMAN> RUN {

ALLOCATE CHANNEL c1 DEVICE TYPE sbt;

ALLOCATE CHANNEL c2 DEVICE TYPE sbt;

ALLOCATE CHANNEL c3 DEVICE TYPE sbt;

BACKUP

INCREMENTAL LEVEL = 0

(DATAFILE 1,4,5 CHANNEL c1)

(DATAFILE 2,3,9 CHANNEL c2)

(DATAFILE 6,7,8 CHANNEL c3);

SQL 'ALTER SYSTEM ARCHIVE LOG CURRENT';

}

Which statement is true about the command?

A.
It uses multisection backup.
B.
It uses parallelization for the backup set.
C.
It uses asynchronous I/O for the backup.
D.
It creates compressed backup sets.