presto-cassandra/src/main/java/io/prestosql/plugin/cassandra/CassandraClusteringPredicatesExtractor.java/CassandraClusteringPredicatesExtractor/getUnenforcedConstraints
class CassandraClusteringPredicatesExtractor:    public TupleDomain<ColumnHandle> getUnenforcedConstraints()
    {
        Map<ColumnHandle, Domain> pushedDown = clusteringPushDownResult.getDomains();
        Map<ColumnHandle, Domain> notPushedDown = new HashMap<>(predicates.getDomains().get());

        if (!notPushedDown.isEmpty() && !pushedDown.isEmpty()) {
            notPushedDown.entrySet().removeAll(pushedDown.entrySet());
        }

        return TupleDomain.withColumnDomains(notPushedDown);
    }