052-64

Which two statements are true about setting the FAST_START_MTTR_TARGET initialization parameter to a nonzero value? (Choose two.)
A.The MTTR advisor will be disabled.
B.Automatic checkpoint tuning will be enabled.
C.The value for the LOG_CHECKPOINT_INTERVAL initialization parameter will be override the value for FAST_START_MTTR_TARGET.
D.The time taken to recover the instance after the crash is always exactly the same as the value given for the FAST_START_MTTR_TARGET initialization parameter

启用 MTTR Advisor 需要设置 STATISTICS_LEVEL 和 FAST_START_MTTR_TARGET，故 A 错
　　快速启动检查点功能是通过指定所需的非零恢复平均时间（MTTR）值来启用的，该值将用于设置FAST_START_MTTR_TARGET 初始化参数。此参数控制数据库对单个实例执行崩溃恢复所花费的时间量。启用快速启动检查点功能时，Oracle 将自动保持检查点的速度，已便达到请求的 MTTR.如果将该值设置为 0，将禁用此功能，故 B 正确
FAST_START_MTTR_TARGET 会被 LOG_CHECKPOINT_INTERVAL 所覆盖，故 C 正确
D 错误，是在所需时间内或在尽量接近此事件的范围内，并不是指定的时间点