Which two are true about instance recovery? (Choose two.)
A.It is not possible if an archived log is missing. B.It is performed automatically after the database is opened; however, blocks requiring recovery are not available until they are recovered. C.Setting FAST_START_MTTR_TARGET to a lower value reduces instance recovery time by causing dirty buffers to be written to disk more frequently, thereby reducing the number of I/Os needed during instance recovery. D.It is performed by the Recovery Writer (RVWR) background process. E.Setting FAST_START_MTTR_TARGET to a higher value reduces instance recovery time by causing The log writer to write more frquently, thereby reducing the number of I/Os needed during instance recovery. F.It is performed automatically while the database remains in MOUNT state. Then the database is opened.正确答案CF
