Question

Mysql max not working, only max id getting but group by is not working

仅显示最小值

CREATE TABLE `feedbacklogs` (
  `fid` int(11) NOT NULL AUTO_INCREMENT,
  `remarks` varchar(255) NOT NULL,
  `eid` int(11) NOT NULL,
  PRIMARY KEY (`fid`)
) ENGINE=MyISAM AUTO_INCREMENT=4081 DEFAULT CHARSET=latin1

select status,max(fid) from feedbacklogs group by eid

我得到了错误的值

SELECT eid,remarks,max(fid) FROM feedbacklogs
group by eid

请给我解决方法

样本数据

fid - 01 , status - active, eid-70
fid - 02 , status - deleted, eid-72
fid - 03 , status - deleted, eid-70

实际结果：fid-03，状态-已删除，eid-70

i get：fid-03，status-active，eid-70

Answer 1

当group by中的列与SELECT中没有聚合函数的列不匹配时，这些列的值是不可预测的

（这种情况在mysql版本<5.7 for mysql> = 5.7时发生，默认情况下会使用group by引发错误）

setValue()

您应该使用

SELECT eid,remarks,max(fid) FROM feedbacklogs
group by eid

或

SELECT eid,remarks,max(fid) FROM feedbacklogs
group by eid, remarks

或者如果您想对max_fid进行评论

 SELECT eid,min(remarks),max(fid) FROM feedbacklogs
group by eid

MySQL max group by返回错误的值

1 个答案: