MySQL query to return a daily 30-day count答案

【问题标题】：MySQL query to return a daily 30-day countMySQL query to return a daily 30-day count
【发布时间】：2022-11-09 11:00:12
【问题描述】：

Let's say that one has a pair of tables:

users

user_id	email
1	email1@test.com
2	email2@test.com
...	...

logins

login_id	user_id	date_login
1	1	2038-01-19 03:14:07
2	1	2038-01-19 03:14:08
3	2	2038-01-19 03:14:08
...	...	...

and one wanted to get a list of totals of "active users" for each day of the last year; where "active user" is defined as anyone who had logged in within 30 days of each date in question.

e.g. result: | date_count | activeuser_count | | -------- | -------------- | | 2038-01-19 | 2345 | | 2038-01-20 | 3456 | | 2038-01-21 | 4321 | | ... | ... |

How would one do this most efficiently / with the fewest number of queries?

标签： mysql

【解决方案1】：

select * from users inner join logins on users.user_id = logins.user_id where date_diff(now(), date_login) <= 30

Sorry: was looking for the total number of active users for each day, not a list of the active users for each day