Explanation:
Oracle recommends DBA after a recover from the loss of the current online redo log file to perform offline backup of the entire database.
Incorrect Answers:
1: You need to backup offline the entire database, not just the data files.
2: There is no instance backup in Oracle, only database backup, because Oracle instance itself is just set of some processes in memory.
4: Backing up the control file is not enough in this situation. You need to back up the control file after any table space or datafiles structural changes in the Oracle database.
5: You don't need to archive any unarchived online redo logs after this type pf recovery.
Oracle 8, DBA Certification Exam Guide, Jason S. Couchman, p. 709-711
Chapter 15: Advanced Topics in Data Recovery

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