Users want to get rounding mode in `quantileExact` equivalent to "median_low" from Python:
https://docs.python.org/3/library/statistics.html#statistics.median_low
while current implementation works equivalent to "median_high" (?)
offsets_to.push_back(offsets_to.back() + size);
            if (!size)
                return;
            if constexpr (returns_float)
            {
                auto & data_to = assert_cast<ColumnVector<FloatReturnType> &>(arr_to.getData()).getData();
                size_t old_size = data_to.size();
                data_to.resize(data_to.size() + size);
                data.getManyFloat(levels.levels.data(), levels.permutation.data(), size, data_to.data() + old_size);
            }
            else
            {
                auto & data_to = static_cast<ColVecType &>(arr_to.getData()).getData();
                size_t old_size = data_to.size();
                data_to.resize(data_to.size() + size);
                data.getMany(levels.levels.data(), levels.permutation.data(), size, data_to.data() + old_size);
            }
        }
        else
        {
            if constexpr (returns_float)
                assert_cast<ColumnVector<FloatReturnType> &>(to).getData().push_back(data.getFloat(level));
            else
                static_cast<ColVecType &>(to).getData().push_back(data.get(level));
        }
    }
    static void assertSecondArg(const DataTypes & types)
    {
        if constexpr (has_second_arg)
        {