Yii Query

public function actionIndex()
    {
        $sql = "SELECT * FROM tbl_now_playing e ORDER BY e.id DESC";

        $dependency = new CDbCacheDependency('SELECT MAX(update_time) FROM news');
        $rows = Yii::app()->db->cache(10000, $dependency)->createCommand($sql)->queryAll();

        $ConvToJSON = CJSON::encode($rows);
        echo '{"items":'. $ConvToJSON .'}';
        Yii::app()->end();
    }