Question

我有一个MYSQL数据库的查询，如下所示：

SELECT name,
SUM(IF(date_format (date, '%b, %Y')= 'Dec, 2011', 1,0)) AS `month1`, 
SUM(IF(date_format (date, '%b, %Y')= 'Jan, 2012', 1,0)) AS `month2`, 
SUM(IF(date_format (date, '%b, %Y')= 'Feb, 2012', 1,0)) AS `month3`, 
etc...
COUNT(*) AS total FROM table order by total

然而，除了总数之外，我需要平均每月1到12个月。

编辑 - 我需要保留SUMMED数字（第1,2个等），但我还需要计算它们的平均值。

所以，如果month1-12的结果是 -

55,60,70,54,89,58,68,78,65,89,73,81 而TOTAL是840

我需要计算所有这些数字的平均值（70）

由于

Answer 1

SELECT name,
AVG(IF(date_format (date, '%b, %Y')= 'Dec, 2011', 1,0)) AS `month1`, 
AVG(IF(date_format (date, '%b, %Y')= 'Jan, 2012', 1,0)) AS `month2`, 
AVG(IF(date_format (date, '%b, %Y')= 'Feb, 2012', 1,0)) AS `month3`, 
-- etc...
COUNT(*) AS total FROM table order by total

Answer 2

简单：

SELECT name,
AVG(IF(date_format (date, '%b, %Y')= 'Dec, 2011', 1,0)) AS `month1`, 
AVG(IF(date_format (date, '%b, %Y')= 'Jan, 2012', 1,0)) AS `month2`, 
AVG(IF(date_format (date, '%b, %Y')= 'Feb, 2012', 1,0)) AS `month3`, 
etc...
COUNT(*) AS total FROM table order by total

MySQL中求和变量的平均值

2 个答案: