题解 | #统计作答次数#
统计作答次数
https://www.nowcoder.com/practice/45a87639110841b6950ef6a12d20175f
select
count(1) as total_pv,
count(
case
when submit_time is not null then submit_time
end
) as complete_pv,
count(distinct case when submit_time is not null then exam_id end) as complete_exam_cnt
from
exam_record;
