Question

我有一张表记录了当时登录的用户。我需要生成一个报告，以显示用户每月登录的次数。我该怎么做？

- Edit-- 我可以打印每个用户在一个月内出现X次，这对我来说没问题。但我想显示一个月度列表，显示一个月内登录5次的人数。

Answer 1

SELECT
  User
, DATE_FORMAT(LoggedInTime, '%Y-%m') As YearMonth
, COUNT(*) AS NumLogins
FROM user_logins
GROUP BY User, YearMonth

Answer 2

此处可用的主要选项（IMO）是计算用户每月在群组中出现的次数，如下所示：

SELECT user_id,
       count(datetime) as logins, 
       MONTH(datetime) as month 
FROM table
GROUP BY 1, 3

对于mysql中的日期和时间函数，请查看手册here

Answer 3

来自评论：“我想显示登录的用户数超过5次”

SELECT YearMonth, COUNT(User)
FROM (
  SELECT
    User
  , DATE_FORMAT(LoggedInTime, '%Y-%m') As YearMonth
  FROM user_logins
  GROUP BY User, YearMonth
  HAVING COUNT(*) > 5
)GROUP BY YearMonth

在MYSQL中查找重复项

3 个答案: