"unnamed datafile(s) added to control file by media recovery"
*Cause: Media recovery with a backup control file or a control file that
was rebuilt, encountered the creation of a datafile that was not
in the control file. An entry has been added to the control file
for the new datafiles, but with the file name UNNAMEDnnnn, where
nnnn is the file number. Attached errors describe the file names
that were originally used to create the files.
*Action: Rename the files to valid file names and resume recovery. If
necessary the command ALTER DATABASE CREATE DATAFILE may be used
to create a file suitable for recovery and do the rename. If the
file is not going to be recovered then take it offline with the
FOR DROP option.