"refresh was aborted because of conflicts caused by deferred transactions"
*Cause: There are outstanding conflicts logged in the DEFERROR table at
the materialized view's master site.
*Action: Resolve the conflicts in the master DEFERROR table and refresh
again after the table is empty. Alternatively, refresh with
REFRESH_AFTER_ERRORS, even if there are conflicts in the master's
DEFERROR table. Proceeding despite conflicts can result in an
updatable materialized view's changes appearing to be temporarily
lost, until a refresh succeeds after the conflicts are resolved.