/**
* List the courses ids.
*
* @param $query
* @return mixed
*/
public function scopeListCourses($query)
{
return $query->lists(Course::table() . "." . Course::primaryKey());
}
/**
* Get all the courses in the database along
* with the average rating for each course.
*
* @param $query
* @return mixed
*/
public function scopeRated($query)
{
$course_average_rating = CourseLikes::averageRating()->toSql();
$join_table = \DB::raw("({$course_average_rating}) as {$this->averageRatingTable()}");
return $query->leftJoin($join_table, function ($join) {
$join->on(Course::table() . '.' . Course::primaryKey(), '=', $this->averageRatingTable() . '.' . CourseLikes::courseForeignKey());
});
}
