The recommended method of upgrading existing dictionaries or
  repositories is to use the CDD$UPGRADE.COM command procedure.  The
  CDD$UPGRADE.COM command procedure automatically invokes the appropriate
  upgrade utility based on the version number you specify.  The procedure
  is provided with the Oracle CDD/Repository installation.

  If you are performing an upgrade from a Version 5.n repository to a
  later Version 5.n or higher repository, CDD$UPGRADE.COM runs the CDO
  CONVERT utility using the CDO CONVERT/REPOSITORY command.  This is
  referred to as a minor upgrade.

  In Version 5.0, the upgrade portion of the CONVERT command was
  disabled.  However, in Version 5.1 and later, CDO CONVERT/REPOSITORY
  can be used to perform a minor upgrade.

  If you are performing an upgrade from a Version 4.n dictionary, the
  CDD$UPGRADE.COM procedure runs CDDX, the repository translation
  utility, using the REPOSITORY EXPORT and REPOSITORY IMPORT commands.
  This type of upgrade is referred to as a major upgrade.

  Note:  DMU dictionaries do not require an upgrade.

  The CDD$UPGRADE.COM procedure and the REPOSITORY IMPORT and REPOSITORY
  EXPORT commands must be invoked from the DCL level.  See the CDDX help
  topic for information on the REPOSITORY IMPORT and REPOSITORY EXPORT
  commands.

  You invoke the CONVERT/REPOSITORY command from CDO.  See the
  description of the CDO CONVERT command in the CDO utility online help.

1  –  Preparing for Upgrade

  Before you upgrade a repository or use the REPOSITORY EXPORT command,
  check the following:

   o  Ensure that you have SYSPRV or BYPASS privilege

   o  Check the paging file quota (PGFLQUOTA)

      The .CDDX export file requires approximately one half the number of
      blocks used by the CDD$DATABASE.RDB file.

      The following table lists the PGFLQUOTA values required for the
      upgrade:

       CDD$DATABASE.RDB Size        Required PGFLQUOTA
      ---------------------------------------------------
            0-20,000 blocks        50,000-200,000 pages
       20,000-35,000 blocks        70,000-200,000 pages
       35,000-55,000 blocks       100,000-200,000 pages
       55,000 + blocks                    200,000 pages
      ---------------------------------------------------

   o  Verify the repository

   o  If you do not have an adequate backup of your repository, perform a
      backup operation.

      See the instructions in the Oracle CDD/Repository User's Guide for
      verifying and backing up a repository.

   o  If you issue the REPOSITORY EXPORT command directly from the DCL
      level, redefine the CDD$SEPARATOR as a slash character (/) if any
      repository elements contain a period (.) in the name.

   o  If you are installing Oracle CDD/Repository, check for the
      SYS$SHARE:CDA$ACCESS.EXE image, which is required by the upgrade
      images.

      Also, if you installing Oracle CDD/Repository and the process you
      are in was created before the installation, log out and log back in
      again before executing the CDD$UPGRADE.COM procedure (or run
      CDD$UPGRADE.COM from the installing account) to update DCL
      commands.