struct [[eosio::table]] poll
{
  uint64_t key; // primary key
  uint64_t pollId; // second key, can be non-unique
  std::string pollName; // name of poll
  uint8_t pollStatus =0; // staus where 0 = closed, 1 = open, 2 = finished
  std::string option; // the item you can vote for
  uint32_t count =0; // the number of votes for each time

  uint64_t primary_key() const { return key; }
  uint64_t by_pollId() const {return pollId; }
};

_polls.emplace(get_self(), [&](auto& p) {
        p.key = _polls.available_primary_key(); // method
        p.pollId = _polls.available_primary_key();
        p.pollName = pollName;
        p.pollStatus = 0;
        p.option = "";
        p.count = 0;
    });