请考虑我们Users表中的这段摘录：
+-------------+---------------------+---------------------+
| id | last_login | created |
+-------------+---------------------+---------------------+
| 14551578822 | 2014-02-22 17:38:39 | 2013-03-26 23:30:50 |
| 18442388426 | 0000-00-00 00:00:00 | 2013-11-07 15:51:11 |
| 49983341634 | 2014-03-06 22:28:47 | 2013-03-23 16:00:05 |
| 9527246957 | 2014-01-17 02:37:53 | 2013-05-14 02:14:49 |
| 58667409337 | 2014-03-08 06:54:01 | 2013-05-15 01:52:23 |
| 1907780002 | 2014-03-01 03:24:04 | 2013-05-01 07:57:56 |
| 65319490251 | 2014-03-19 05:49:41 | 2013-03-23 08:53:43 |
| 23896465717 | 0000-00-00 00:00:00 | 2012-10-21 10:52:23 |
| 19147401900 | 0000-00-00 00:00:00 | 2013-05-01 17:43:28 |
| 28598429318 | 0000-00-00 00:00:00 | 2014-03-14 14:44:15 |
+-------------+---------------------+---------------------+
我们有很多很多用户——我们希望生成一个报告，显示随着日期的增加我们拥有的用户总数。我们希望输出类似于：
+---------+---------------+
| DATE | User Count |
+---------+---------------+
| 2012-08 | 122 |
| 2012-09 | 1746 |
| 2012-10 | 3847 |
| 2012-11 | 5826 |
...
| 2014-03 | 472647 |
| 2014-04 | 497286 |
+---------+---------------+
一定有某种方法可以做到这一点，而不必再选其他人，也不必像那样搞得一团糟。我已经有一个表，通过以下查询显示每个时段的连接数：
SELECT DATE(users.created) as JOIN_DATE , COUNT(users.id) AS JOIN_COUNT from users
WHERE users.created > '2012-07-01 00:00:00'
GROUP BY JOIN_DATE
ORDER BY JOIN_DATE ASC
只是想知道有没有办法这样做。
谢谢！
最佳答案
您可以使用一个变量来总结每次迭代的总体
SELECT t.date ,
@population := @population+t.per_time population
FROM (
SELECT
DATE_FORMAT(`last_login` ,'%Y-%m') `date`,
COUNT(*) per_time
FROM Table1
WHERE created > '2012-07-01 00:00:00'
GROUP BY `date` ) t ,
(SELECT @population:=0) p
Fiddle Demo
关于mysql - 如何在DATE之前将User表的填充量选择为递增值？，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/22804363/