之前一直以为group by只能一个字段,没想到可以加多个字段,以下示例就是以开始日期,教练id作为分组条件,然后还可以通过count()函数统计出该分组下的数量,害的我傻乎乎的用脚本去统计,牛啊
SELECT start_date,coach_id,count(start_date) as result_num FROM team_course_schedule
WHERE id in
(SELECT schedule_id FROM `team_course_reserve` WHERE brand_id = 273567221088319 and is_checkin = 1 GROUP BY schedule_id)
and schedule_status!=4
GROUP BY start_date,coach_id