presto-main/src/main/java/io/prestosql/sql/planner/plan/StatisticAggregationsDescriptor.java/StatisticAggregationsDescriptor/getColumnStatistics
class StatisticAggregationsDescriptor:    @JsonProperty
    @JsonSerialize(keyUsing = ColumnStatisticMetadataKeySerializer.class)
    @JsonDeserialize(keyUsing = ColumnStatisticMetadataKeyDeserializer.class)
    public Map<ColumnStatisticMetadata, T> getColumnStatistics()
    {
        return columnStatistics;
    }