The CDDX utility creates an export file using the filename supplied in
  the REPOSITORY EXPORT command with a default extension of CDDX.

  Before issuing the REPOSITORY EXPORT command, make sure you have
  performed the steps necessary to prepare for an upgrade.  See the
  CDD_REPOSITORY Upgrade_Procedure help topic or the Oracle
  CDD/Repository User's Guide for instructions.

  If your repository is corrupt and you issue the REPOSITORY EXPORT
  command, EXPORT displays warning messages.  Oracle CDD/Repository
  attempts to export accessible portions of corrupt elements or to skip
  over elements that are too incomplete to be exported.

  The REPOSITORY EXPORT command creates an intermediate export file of
  your repository using the file name you specify.  If you have delta
  files, it also creates a CDD$UPGRADE.BAK backup file.  It places the
  .CDDX file and the .BAK file (if one was created) in your current
  directory by default, or you can specify another device and directory.

  Be sure you do not delete the .CDDX export file or the .BAK file (if
  one was created).

  $ REPOSITORY EXPORT [qualifiers] [parameters]