Any Idea How To Select Stat Count = 0?

I have two tables, courses and participants. courses has many participants




courses

	courseID [PK]

	courseName


participants

	ID [PK]

	courseID [FK]

        staffID



in my course model, I had define the relations as below




	public function relations()

	{

		return array(

			'participantsCount' => array(self::STAT, 'participants', 'courseID'),

		);

	}



May I know how can I use cgridview to list out all courses with the ‘participantsCount’ = 0