在一个 SQL 查询中求和和计数

Question

我有这种数据

time                                               Members
-------------------------------------------------- -----------
Jun 23 2016                                           1
Jun 23 2016                                           1
Jun 23 2016                                           2
Jun 29 2016                                           6
Jul 11 2016                                           3
Jul 11 2016                                           1
Jul 13 2016                                           1

我使用这个 sql 查询获得了这个数据

SELECT CONVERT (VARCHAR(12), a.registered_time), COUNT(b.member_id) AS Members
FROM b
Inner JOIN a ON b.mirror_id = a.mirror_id 
GROUP BY 
(a.registered_time) order by a.registered_time

如果它们是同一日期，我想获得总数的总和，例如 2016 年 6 月 23 日的日期将有 4 个成员，依此类推。是否可以在 Count() 上有 SUM() 函数？我该怎么做？

Answer 1

将值转换为date 并将其包含在select 和group by 中：

SELECT CONVERT(date, a.registered_time) as dte, COUNT(b.member_id) AS Members
FROM b JOIN
     a
     ON b.mirror_id = a.mirror_id 
GROUP BY CONVERT(date, a.registered_time)
ORDER BY CONVERT(date, a.registered_time);