78.You are managing an Oracle Database 11g database. The database is open,and you plan to perform Recovery Manager (RMAN) backups. Which three statements are true about these backups? (Choose three.) A.The backups would be consistent. B.The backups would be inconsistent. C.The backups would be possible only if the database is running in ARCHIVELOG mode. D.The backups would be possible only if the database is running in NOARCHIVELOG mode. E.The backups need to be restored and the database has to be recovered in case of a media failure. 答案：BCE 解析：只要是open状态进行备份的都是不一致备份排除A rman在非归档模式下执行进行脱机备份也就是冷备，因此排除D E说的是介质有问题了，备份必须restore然后recovered，这里说一下restore和recover的区别 restore：从备份位置还原
一个或者多个
数据库文件 recover:应用归档和联机重做日志
文件，将整个
数据库或单独
数据库文件前滚到指定的scn 这就是归档
文件的作用，当执行备份的时候，只是备份到
一个点的数据，但是在备份之后这段时间执行的数据，就需要 通过recover利用归档日志，来进行前滚实现，因此需要这两步
