presto-hive/src/main/java/io/prestosql/plugin/hive/PartitionStatistics.java/PartitionStatistics/toString
class PartitionStatistics:    @Override
    public String toString()
    {
        return toStringHelper(this)
                .add("basicStatistics", basicStatistics)
                .add("columnStatistics", columnStatistics)
                .toString();
    }