按原则分组使用月份,年份2

Question

如何在doctrine2中将以下SQL查询编写为DQL.

SELECT COUNT(id)  
FROM stats  
WHERE YEAR(record_date) = 2009  
GROUP BY YEAR(record_date), MONTH(record_date)

即我希望group by结果基于存储在MySQL表中的月份,日期时间字段的年份.

Answer 1

在DQL中,您还可以按月,年,日等分组SUBSTRING.

例如 - group by month (datetime format Y-m-d H:i:s):

SELECT p, SUBSTRING(p.date, 6, 2) as month
FROM Entity p
GROUP BY month