text: CREATE TABLE IF NOT EXISTS user_vote
  (
      user_id   BIGINT  NOT NULL,
      poll_id   INTEGER NOT NULL,
      option    INTEGER NOT NULL,
      PRIMARY KEY (user_id, poll_id)
  );
  
  CREATE INDEX IF NOT EXISTS user_vote_index ON user_vote (user_id, poll_id);
  CREATE INDEX IF NOT EXISTS poll_index ON user_vote (poll_id);
  