题解 | #统计作答次数#
统计作答次数
https://www.nowcoder.com/practice/45a87639110841b6950ef6a12d20175f
SELECT COUNT(id) AS total_pv, SUM(IF(submit_time IS NOT NULL AND score IS NOT NULL, 1, 0)) AS complete_pv, (select count(distinct exam_id) from exam_record where submit_time IS NOT NULL AND score IS NOT NULL) AS complete_exam_cn FROM exam_record;