code: public function values($values)
      {
          if (is_array($values) === true) {
              if (is_numeric(key($values)) === true) {
                  $this->values = array(
                      null,
                      implode(', ', $values)
                  );
              } else {
                  $this->values = array('', '');
                  foreach ($values as $key => $value) {
                      if (stripos($key, '.') !== false) {
                          $key = substr($key, stripos($key, '.') + 1);
                      }
                      $this->values[0] .= $key . ', ';
                      $this->values[1] .= $value . ', ';
                  }
                  $this->values[0] = substr($this->values[0], 0, -2);
                  $this->values[1] = substr($this->values[1], 0, -2);
              }
          } else {
              $this->values = array(
                  null,
                  $values
              );
          }
  
          return $this;
      }
docs: Set values clause.
  
  @param  array|string $values values clause
  @return Insert       this