我正在进行一项查询,它将计算每个用户的唯一登录天数,将它们放入一个桶中(1-2,3-4个登录日等),并返回每个用户的数量.按部门划分.如果不太清楚我会道歉,希望下面的例子有助于说明我的问题.
我有这样一张桌子:
+-------------+-----------+------------+-----------------+
| time | user_name | dept | event |
+-------------+-----------+------------+-----------------+
| 2016-01-04 | Joe | finance | logged in |
| 2016-01-04 | Jeff | marketing | logged in |
| 2016-01-04 | Jeff | marketing | project created |
| 2016-01-04 | Bob | finance | logged in |
| 2016-01-04 | Mark | accounting | logged in |
| 2016-01-05 | Bob | finance | logged in |
| 2016-01-08 | Bob | finance | …