mysql中根据月进行分组

SELECT
Count(*),
ri_equipmentmessage_equipment.equipment_Name,
ri_equipmentmessage_equipment.equipment_Code,
DATE_FORMAT(
		ri_repair_declarationsurface.report_Time,
		'%m'
	) AS months,
ri_department.departmentName
FROM
ri_repair_declarationsurface
INNER JOIN ri_equipmentmessage_equipment ON ri_repair_declarationsurface.equipment_Id = ri_equipmentmessage_equipment.id
INNER JOIN ri_department ON ri_equipmentmessage_equipment.department = ri_department.id
GROUP BY
	months,
ri_equipmentmessage_equipment.equipment_Code

主要是一个DATE_FORMAT()方法的使用

详细见

https://blog.csdn.net/benzun_yinzi/article/details/77449985