std::pair<iterator, iterator> get_all(const TId id) {
auto result_main = m_main.get_all(id);
auto result_extra = m_extra.get_all(id);
return std::make_pair(iterator(result_main.first, result_main.second, result_extra.first, result_extra.second),
iterator(result_main.second, result_main.second, result_extra.second, result_extra.second));
}
