This section discusses use of the RDMS$USE_OLD_UPDATE_RULES
    logical name to preserve update behavior. You cannot modify or
    erase records in a relation if the relation is joined with other
    relations.

                                   NOTE

       This restriction applies to RDO, RDBPRE, and RDML only. SQL
       syntax does not allow this type of update.

    However, updates to a relation are allowed if you join the
    relation with other relations in a subquery.

    This update restriction can cause applications that depend on
    the previous update behavior to fail unless update queries are
    modified. You can use the RDMS$USE_OLD_UPDATE_RULES logical
    name to retain the previous update behavior, then modify your
    applications.

    Define the RDMS$USE_OLD_UPDATE_RULES logical name to be 1, as
    shown below, to enforce the old update rules.

    $ DEFINE RDMS$USE_OLD_UPDATE_RULES 1

    Support for this logical name will be removed in a future release
    of Oracle Rdb.