YII 操作数据库的三种方式

<?php
class DbController extends Controller
{
    protected function afterAction($action)
    {
        $time = sprintf('%0.5f', Yii::getLogger()->getExecutionTime());
        $memory = round(memory_get_peak_usage()/(1024*1024),2)."MB";
        echo "Time: $time, memory: $memory";
        parent::afterAction($action);
    }
 
    public function actionAr()
    {
        $actors = Actor::model()->findAll(array('with' => 'films',
                'order' => 't.first_name, t.last_name, films.title'));
        echo '<ol>';
        foreach($actors as $actor)
        {
            echo '<li>';
            echo $actor->first_name.' '.$actor->last_name;
            echo '<ol>';
            foreach($actor->films as $film)
            {
                echo '<li>';
                echo $film->title;
                echo '</li>';
            }
            echo '</ol>';
            echo '</li>';
        }
        echo '</ol>';
    }
 
    public function actionQueryBuilder()
    {
        $rows = Yii::app()->db->createCommand()
                ->from('actor')
                ->join('film_actor', 'actor.actor_id=film_actor.actor_id')
                ->leftJoin('film', 'film.film_id=film_actor.film_id')
                ->order('actor.first_name, actor.last_name, film.title')
                ->queryAll();
        $this->renderRows($rows);
    }
 
    public function actionSql()
    {
        $sql = "SELECT * FROM actor a
             JOIN film_actor fa ON fa.actor_id = a.actor_id
             JOIN film f ON fa.film_id = f.film_id
             ORDER BY a.first_name, a.last_name, f.title";
        $rows = Yii::app()->db->createCommand($sql)->queryAll();
        $this->renderRows($rows);
    }
 
    public function renderRows($rows)
    {
        $lastActorName = null;
        echo '<ol>';
        foreach($rows as $row)
        {
            $actorName = $row['first_name'].' '.$row['last_name'];
            if($actorName!=$lastActorName){
                if($lastActorName!==null){
                    echo '</ol>';
                    echo '</li>';
                }
                $lastActorName = $actorName;
                echo '<li>';
                echo $actorName;
                echo '<ol>';
            }
            echo '<li>';
            echo $row['title'];
            echo '</li>';
        }
        echo '</ol>';
    }
}