presto-tpch/src/main/java/io/prestosql/plugin/tpch/statistics/StatisticsEstimator.java/StatisticsEstimator/min
class StatisticsEstimator:    @SuppressWarnings("unchecked")
    private Object min(Object l, Object r)
    {
        checkSameType(l, r);
        Comparable<Object> left = checkType(l, Comparable.class);
        Comparable<Object> right = checkType(r, Comparable.class);
        return left.compareTo(right) < 0 ? left : right;
    }