Nette\Database\Table\ActiveRow::__isset PHP Метод

    public function __isset($key)
    {
        if ($this->accessColumn($key)) {
            return isset($this->data[$key]);
        }
        $this->removeAccessColumn($key);
        return FALSE;
    }

 public function __unset($key)
 {
     $column = $this->formatColumnName($key);
     if (parent::__isset($column) || !ObjectMixin::has($this, $key)) {
         parent::__unset($column);
     } else {
         ObjectMixin::remove($this, $key);
     }
 }