Yii : how to count records in a model?

the right usage of count():

    $userid =  Yii::app()->user->uid;
    $count = Notification::model()->count( 'user_id=:userid', array(':userid' => $userid));

Please see http://www.yiiframework.com/doc/api/1.1/CActiveRecord#count-detail

$notifyModels = Notification::model()->findAllByAttributes(array(
            'user_id'=> Yii::app()->user->uid
        ));

$count = count($notifyModels);

Or

$count = Notification::model()->countByAttributes(array(
            'user_id'=> Yii::app()->user->uid
        ));