MySQL DATETIME 字段上的 GROUP BY 月份
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GROUP BY month on DATETIME field
提问by David542
I have the following query in mysql:
我在 mysql 中有以下查询：
SELECT title,
added_on
FROM title
The results looks like this:
结果如下所示：
Somos T?o Jovens 2013-10-10 16:54:10
Moulin Rouge - Amor em Vermelho 2013-10-10 16:55:03
Rocky Horror Picture Show (Legendado) 2013-10-10 16:58:30
The X-Files: I Want to Believe 2013-10-10 22:39:11
I would like to get the count for the titles in each month, so the result would look like this:
我想获得每个月的标题计数，因此结果如下所示：
Count Month
42 2013-10-01
20 3013-09-01
The closest I can think of to get this is:
我能想到的最接近的是：
SELECT Count(*),
Date(timestamp)
FROM title
GROUP BY Date(timestamp)
But this is only grouping by the day, and not the month. How would I group by the month here?
但这只是按天分组，而不是按月分组。我将如何按月份分组？
回答by Jason Heo
Could you try this?
你能试试这个吗？
select count(*), DATE_FORMAT(timestamp, "%Y-%m-01")
from title
group by DATE_FORMAT(timestamp, "%Y-%m-01")
Please, note that MONTH()can't differentiate '2013-01-01' and '2014-01-01' as follows.
请注意，MONTH()不能如下区分“2013-01-01”和“2014-01-01”。
mysql> SELECT MONTH('2013-01-01'), MONTH('2014-01-01');
+---------------------+---------------------+
| MONTH('2013-01-01') | MONTH('2014-01-01') |
+---------------------+---------------------+
| 1 | 1 |
+---------------------+---------------------+
回答by NewInTheBusiness
SELECT Count(*),
Date(timestamp)
FROM title
GROUP BY Month(timestamp)
Edit: And obviously if it matters to display the 1st day of the month in the results, you do the DATE_FORMAT(timestamp, "%Y-%m-01")thing mentioned in some other answers :)
编辑：很明显，如果在结果中显示当月的第一天很重要，你会做DATE_FORMAT(timestamp, "%Y-%m-01")一些其他答案中提到的事情:)
回答by The Hungry Dictator
select
count(*) as Count,
MONTH(timestamp)+"-"+YEAR(timestamp) as Month
from
title
GROUP BY
MONTH(tumestamp);
回答by SirPhemmiey
The best bet is to group it by YEAR and then by MONTH. See below
最好的办法是按 YEAR 分组，然后按 MONTH 分组。见下文
SELECT Count(*), Date(timestamp) FROM title GROUP BY YEAR(timestamp), Month(timestamp)
回答by Surabhil Sergy
select count(*), date(timestamp) from title group by MONTHNAME(timestamp)
