error: ‘row’ in namespace ‘pqxx’ does not name a type

I compiled my c++ program using libpqxx on my development machine. but in deployment machine i got this error: error: ‘row’ in namespace ‘pqxx’ does not name a type i installed same version libpqxx on deployment machine.

boost::property_tree::ptree UserModel::GetUsersJson(int page, std::string query){
    pqxx::result R = GetUsers(page, query);
    int count = R.size();
    int pageCount = count / OFFSET_COUNT;
    boost::property_tree::ptree users_node;
    boost::property_tree::ptree user_node;
    for(pqxx::row r : R)
    {
        user_node.put("id", r[0]);
        user_node.put("email", r[1]);
        user_node.put("password", r[2]);
        user_node.put("details", r[3]);
        user_node.put("created_at", r[4]);
        users_node.push_back(std::make_pair(r[0].c_str(), user_node));
    }
    return users_node;
}