题解 | #统计作答次数#
统计作答次数
https://www.nowcoder.com/practice/45a87639110841b6950ef6a12d20175f
select count(start_time) as total_pv, count(score) as complete_pv, count(distinct case when score is null then null else exam_id end) as complete_exam_cnt from exam_record;
