Syntax options:

       FOR EXCLUSIVE
       FOR PROTECTED
       FOR SHARED

    Specifies the SQL share modes. The keyword you choose determines
    which operations you allow others to perform on the tables you
    are reserving. While you can specify an EXCLUSIVE or PROTECTED
    share mode when declaring a read-only transaction, SQL ignores
    these entries and specifies SHARED mode. The default is SHARED.
    For more information, see the Oracle Rdb SQL Reference Manual.