/FILE = {COLLECTION | DUMP [=n]}

    If analyzing multiple dump files from a partial dump copy, or
    if a separate collection file is in use, the /FILE qualifier
    indicates whether the SHOW DUMP command applies to one of the
    dump files or to the collection file.

    If /FILE is not specified, by default, the SHOW DUMP/SUMMARY,
    SHOW DUMP/HEADER, SHOW DUMP/COLLECTION, and SHOW DUMP/ALL
    commands apply to all open files, and the SHOW DUMP/LMB=ALL and
    SHOW DUMP/COMPRESSION commands apply to all open dump files.
    If /FILE=DUMP is specified without a file number, then these
    commands apply to the primary dump file.

    By default, SHOW DUMP/BLOCK applies to the primary dump file. By
    default, SHOW DUMP/LMB=n and SHOW DUMP/COMPRESSION=n apply to the
    primary dump file or to the dump file for which the command was
    last used.

    All other qualifiers are applicable only to the primary dump
    file.