在mysql中处理时间戳

把mysql中时间戳转化成正常时间， 用mysql函数： from_unixtime(数据库time字段，“%Y%m%d”);

例如，按月统计：

select count(id), from_unixtime(select_time,'%Y-%m') as result, from_unixtime(select_time,'%Y')as year, from_unixtime(select_time,'%m') as month
                from diray
                group by  year, month
                order by  year desc, month desc