public function get_all_samples(\core_analytics\analysable $site) {
        global $DB;

        // Getting courses from DB instead of from the site as these samples
        // will be stored in memory and we just want the id.
        $select = 'id != 1';
        $courses = get_courses('all', 'c.sortorder ASC');
        unset($courses[SITEID]);

        $courseids = array_keys($courses);
        $sampleids = array_combine($courseids, $courseids);

        $courses = array_map(function($course) {
            return array('course' => $course, 'context' => \context_course::instance($course->id));
        }, $courses);

        // No related data attached.
        return array($sampleids, $courses);
    }