Mysql按月份为组进行统计排序_MySQL

按年份进行group，统计排序：

SELECT YERA(established_time),COUNT(*) AS num FROM `table_record` GROUP BY YEAR (established_time)

按月份进行group，统计排序：

方法一：简单实用

SELECT YEAR(established_time) AS 'year' , MONTH(established_time) AS 'month' , COUNT(*) AS 'count' FROM `table_record` 
GROUP BY YEAR (established_time) DESC, MONTH(established_time)
效果：
  year   month   count  
  ------   ------      --------
  2014       1      8320
  2014       2      5837
  2014       3     25069
  2014       4     29910
  2014       5     25018
  2014       6     17347
  2014       7         1    
  2013       1      9114
  2013       2      4258
方法二：利用MySql内置字符串连接函数 CONCAT(str1, str2, ...,str3) 。
SELECTCONCAT(YEAR(established_time),',',MONTH( established_time)) AS data_time ,COUNT(*) AS num FROM `table_record` #group by data_timeGROUP BY YEAR(established_time) DESC,MONTH( established_time)
效果：
data_time     num  
---------  --------
2014,1         8320
2014,2         5837
2014,3        25069
2014,4        29910
2014,5        25018
2014,6        17347
2014,7            1   
2013,1         9114
2013,2         4258
注意这里不要用：
SELECTYEAR(established_time)+MONTH( established_time) as data_time 
这是错误的，它会造成2010+1=2011的这样的错误。
此外，若仅仅用下面语句，是统计的是多年来每月的数据。
SELECTMONTH(established_time) AS 'month' , COUNT(*) AS 'count' FROM `tb_gongshangju_record_beijing` GROUP BYMONTH(established_time) DESC

效果如下：
 
month   count  
------  --------
    12     44952
    11     49720
    10     38587
     9     48967
     8     52874
     7     54082
     6     69532
     5     76999
     4     87289
     3     85249
     2     39997
     1     49017
按日期day进行group，统计排序
SELECT YEAR(established_time) AS 'year' , MONTH(established_time) AS 'month' ,DAY(established_time) AS 'day', COUNT(*) AS 'count' FROM `table_record` WHERE table_record.`established_time` >= '2014-01-01'GROUP BY YEAR (established_time) DESC, MONTH(established_time) DESC ,DAY(established_time) DESC