Method getItemsByTwoKeyColumnsImpl

src/Dictionaries/IPAddressDictionary.cpp:702–780

template <typename AttributeType, typename ValueSetter, typename DefaultValueExtractor>
void IPAddressDictionary::getItemsByTwoKeyColumnsImpl(
    const Attribute & attribute,
    const Columns & key_columns,
    ValueSetter && set_value,
    DefaultValueExtractor & default_value_extractor) const
{
    const auto & first_column = key_columns.front();
    const size_t rows = first_column->size();
    auto & vec = std::get<ContainerType<AttributeType>>(attribute.maps);

    if (const auto * ipv4_col = std::get_if<IPv4Container>(&ip_column))
    {
        const auto * key_ip_column_ptr = typeid_cast<const ColumnVector<UInt32> *>(&*key_columns.front());
        if (key_ip_column_ptr == nullptr)
            throw Exception(ErrorCodes::TYPE_MISMATCH, "Expected a UInt32 IP column");

        const auto & key_mask_column = assert_cast<const ColumnVector<UInt8> &>(*key_columns.back());

        auto comp_v4 = [&](size_t elem, const IPv4Subnet & target)
        {
            UInt32 addr = (*ipv4_col)[elem];
            if (addr == target.addr)
                return mask_column[elem] < target.prefix;
            return addr < target.addr;
        };

        for (const auto i : collections::range(0, rows))
        {
            UInt32 addr = key_ip_column_ptr->getElement(i);
            UInt8 mask = key_mask_column.getElement(i);

            auto range = collections::range(0, row_idx.size());
            auto found_it = std::lower_bound(range.begin(), range.end(), IPv4Subnet{addr, mask}, comp_v4);

            if (likely(found_it != range.end() &&
                (*ipv4_col)[*found_it] == addr &&
                mask_column[*found_it] == mask))
            {
                set_value(i, vec[row_idx[*found_it]]);
            }
            else
                set_value(i, default_value_extractor[i]);
        }
        return;
    }

    const auto * key_ip_column_ptr = typeid_cast<const ColumnFixedString *>(&*key_columns.front());
    if (key_ip_column_ptr == nullptr || key_ip_column_ptr->getN() != IPV6_BINARY_LENGTH)
        throw Exception(ErrorCodes::TYPE_MISMATCH, "Expected a FixedString(16) IP column");

    const auto & key_mask_column = assert_cast<const ColumnVector<UInt8> &>(*key_columns.back());

    const auto * ipv6_col = std::get_if<IPv6Container>(&ip_column);
    auto comp_v6 = [&](size_t i, const IPv6Subnet & target)
    {
        auto cmpres = memcmp16(getIPv6FromOffset(*ipv6_col, i), target.addr);
        if (cmpres == 0)
            return mask_column[i] < target.prefix;