code: public function raw($sql, array $params)
      {
          $stmt = $this->connect()->prepare($sql);
          $stmt->execute($params);
  
          if (stripos($sql, 'select') === 0) {
              return $stmt->fetchAll(PDO::FETCH_ASSOC);
          }
  
          if (stripos($sql, 'insert') === 0) {
              return $this->connect()->lastInsertId();
          }
  
  //        if (stripos($sql, 'update') === 0 || stripos($sql, 'delete') === 0 || stripos($sql, 'replace') === 0) {
              return $stmt->execute();
  //        }
      }
docs: Run raw sql and return result.
  
  @param $sql
  @param array $params
  @return array|int
  @throws \PDOException