code: public function getLastInsertID($sequenceName = '')
      {
          if ($this->db->isActive) {
              return $this->db->pdo->lastInsertId($sequenceName === '' ? null : $this->quoteTableName($sequenceName));
          }
  
          throw new InvalidCallException('DB Connection is not active.');
      }
docs: Returns the ID of the last inserted row or sequence value.
  @param string $sequenceName name of the sequence object (required by some DBMS)
  @return string the row ID of the last row inserted, or the last value retrieved from the sequence object
  @throws InvalidCallException if the DB connection is not active
  @see https://secure.php.net/manual/en/function.PDO-lastInsertId.php