WITH t as( SELECT exam_record.uid, SUM(IF(submit_time IS NULL,1,0)) AS incomplete_cnt, COUNT(start_time) AS total_cnt, SUM(IF(submit_time IS NULL,1,0)) / COUNT(start_time) AS incomplete_rate, PERCENT_RANK()OVER(ORDER BY SUM(IF(submit_time IS NULL,1,0)) / COUNT(start_time) DESC) AS p_ranking FROM e...