If you know that an archived redo log group has been damaged, immediately back up all datafiles so that you will have a whole database backup that does not require the damaged archived redo log.

• 实际上，归档日志文件丢失并不可怕，只要及时发现，并且目前还没有文件损坏，还不需要进行完全恢复，则马上做一个全库备份，则丢失的归档日志文件不再需要。