presto-cassandra/src/main/java/io/prestosql/plugin/cassandra/CassandraSplitManager.java/CassandraSplitManager/extractClusteringKeyPredicates
class CassandraSplitManager:    private static String extractClusteringKeyPredicates(CassandraPartitionResult partitionResult, CassandraTableHandle tableHandle, CassandraSession session)
    {
        if (partitionResult.isUnpartitioned()) {
            return "";
        }

        CassandraClusteringPredicatesExtractor clusteringPredicatesExtractor = new CassandraClusteringPredicatesExtractor(
                session.getTable(tableHandle.getSchemaTableName()).getClusteringKeyColumns(),
                partitionResult.getUnenforcedConstraint(),
                session.getCassandraVersion());
        return clusteringPredicatesExtractor.getClusteringKeyPredicates();
    }