单选题

访问记录visit表中包含日期date,用户user_id,访问的页面ur...

Question

访问记录visit表中包含日期date,用户user_id,访问的页面url 3个字段，以下哪个选项不能计算'2019-03-11'这一天访问过页面的所有用户数

A. SELECT count(user_id) FROM (SELECT user_id FROM visit WHERE date = '2019-03-11' GROUP BY user_id) f

B. SELECT count(user_id) FROM (SELECT DISTINCT user_id FROM visit WHERE date = '2019-03-11') f

C. SELECT count(DISTINCT user_id) FROM visit WHERE date = '2019-03-11'

D. SELECT count(user_id) FROM visit WHERE date = '2019-03-11' GROUP BY date