What command would you use to set a persistent setting in RMAN so that backups are all written to a tape device?
A. CONFIGURE DEFAULT DEVICE TYPE TO TAPE MEDIA
B. CONFIGURE DEFAULT DEVICE TYPE TO TAPE
C. CONFIGURE DEFAULT DEVICE TYPE TO SBT
D. CONFIGURE DEFAULT DEVICE TYPE TO SBT_TAPE
注:SBT即System Backup to Tape
非磁盘的备份介质。rman支持两种备份通道，一种是磁盘，一种就是sbt。