presto-main/src/main/java/io/prestosql/cost/SymbolStatsEstimate.java/SymbolStatsEstimate/mapDistinctValuesCount
class SymbolStatsEstimate:    public SymbolStatsEstimate mapDistinctValuesCount(Function<Double, Double> mappingFunction)
    {
        return buildFrom(this).setDistinctValuesCount(mappingFunction.apply(distinctValuesCount)).build();
    }