The name of the interchange file that IMPORT uses as a source
    to create the new database. Use either a full or partial file
    specification or a logical name. If you use a simple file name,
    Oracle Rdb looks for the interchange file in the current default
    directory. You must specify a file that was created by the
    Oracle Rdb EXPORT statement. If you do not specify a file type,
    Oracle Rdb uses the default file type, RBR.