presto-main/src/main/java/io/prestosql/cost/StatisticRange.java/StatisticRange/addAndSumDistinctValues
class StatisticRange:    public StatisticRange addAndSumDistinctValues(StatisticRange other)
    {
        double newDistinctValues = distinctValues + other.distinctValues;
        return new StatisticRange(minExcludeNaN(low, other.low), maxExcludeNaN(high, other.high), newDistinctValues);
    }