Updatebypk没有在yii中调用afterSave

I have updatebypk in my controller to update a Model but i found that updatebypk not calling Yii afterSave function.It is the behaviour of updatebypk

Model::updateByPk($key,array('content'=>$content))// it is updating conten 

Model.php

 protected function afterSave()
    {
      parent::afterSave();
       if(!$this->isNewRecord){
        $this->update_time = time();
       $this->update_by = Yii::app()->user->getId();
       $this->save(false);

      }


    }

updateByPk() is using database query directly and not model's save() method and this is why it's not calling afterSave(). This is by design.