多个Group by参数

时间:2013-10-15 23:17:41

标签: mysql group-by

我有一张用户访问的表格

id | visitorid | date      | ..
1  | 12345     | 01-01-2013
2  | 12345     | 01-01-2013
3  | 12345     | 01-01-2013
4  | 99999     | 01-01-2013
...
35 | 243246    | 01-02-2013
..

我想获得一个月的独特访问,所以这样的输出

 day | u_visits
 1   | 33
 2   | 42
 3   | 7

首先,我想通过visitorid进行分组(每天),然后按月份分组。但是当我试图将两者分组时,结果完全错了:

SELECT day(date) AS days, COUNT(id) FROM table WHERE ... GROUP BY visitorid, days

任何人都知道出了什么问题?

1 个答案:

答案 0 :(得分:0)

SELECT 
    DAY(date) AS days, 
    COUNT(DISTINCT(visitorid)) AS `Unique visits`
FROM visits
GROUP BY days

此处有一个fiddle