Nette\Database\Table\Selection::offsetExists PHP Метод

    public function offsetExists($key)
    {
        $this->execute();
        return isset($this->rows[$key]);
    }

 /**
  * Tests if row exists.
  *
  * @param mixed $key Row's primary key to check for.
  * @return bool
  */
 public function offsetExists($key)
 {
     return $this->selection->offsetExists($key);
 }