Specifies the source database files to be written to an .rbr
    file.

    o  The ALIAS argument specifies the alias of an already attached
       database. If the database you want to export is already
       attached, specifying ALIAS avoids the overhead of a second
       attachment to the database and the locking that attachment
       entails.

    o  The FILENAME and PATHNAME arguments both identify the database
       root file associated with the database. If you specify a
       repository path name, the path name indirectly specifies the
       database root file. Because the EXPORT statement does not
       change any definitions in the repository the effect of the
       PATHNAME and FILENAME arguments is the same.