        foreach($course_RET as $period_date)
        {
            // $period_days_append_sql .="(sp.start_time<='$period_date[END_TIME]' AND '$period_date[START_TIME]'<=sp.end_time AND IF(course_period_date IS NULL, course_period_date='$period_date[COURSE_PERIOD_DATE]',DAYS LIKE '%$period_date[DAYS]%')) OR ";
              $period_days_append_sql .="(sp.start_time<='$period_date[END_TIME]' AND '$period_date[START_TIME]'<=sp.end_time AND (cpv.course_period_date IS NULL OR cpv.course_period_date='$period_date[COURSE_PERIOD_DATE]') AND cpv.DAYS LIKE '%$period_date[DAYS]%') OR ";

        }