NetBackup for Oracle uses the eXtensible Markup Language (XML) standard to represent relational database table data that is extracted from an Oracle database.
form the above comment my question is wither oracle client machine sends the database to target storage unit in XML format?
that is probably valid for XML archiver - possibility to backup Oracle data on a table level (export), not database level (RMAN).
However implementations are very rare, I also did not encounter a customer requirement to backup data in this way..
So review the chapter (Appendix F) carefully maybe there is an answer.