053-510

You executed the following command in Recovery Manager (RMAN):
RMAN> REPORT NEED BACKUP days 3;
What is the output of this command?
A. a list of files that require a backup within three days
B. a list of files requiring more than 3 days of archive logs to apply
C. a list of files that RMAN recommends be backed up only once in every three days, based on low volatility
D. a list of files for which a backup has already been performed in the last three days and which is required to be backed up again based on the high number of transactions performed on them

此题的考点是 REPORT NEED BACKUP 命令的用法
列出为了满足配置或保留策略的所需数据文件的列表。
如果 CONFIGURE RETENTION POLICY TO NONE 那么此命令会返回一个错误，因为 RMAN 不能决定需要备份的文件。
也可以使用不同的发展来显示：
REPORT NEED BACKUP DAYS n
显示需要的归档超过指定天数的文件
REPORT NEED BACKUP RECOVERY WINDOW OF n DAYS
显示基于时间保留策略所需要备份的对象
REPORT NEED BACKUP REDUNDANCY n
显示基于冗余度策略所需要备份的对象