报错

Expression #1 of SELECT list is not in GROUP BY clause and contains
nonaggregated column ‘数据库名.表名.字段名’ which is not functionally dependent
on columns in GROUP BY clause; this is incompatible with
sql_mode=only_full_group_by

原因

MySQL错误-this is incompatible with sql_mode=only_full_group_by完美解决方案_格子衫111的博客-CSDN博客有时候，遇到数据库重复数据，需要将数据进行分组，并取出其中一条来展示，这时就需要用到group by语句。但是，如果mysql是高版本，当执行group by时，select的字段不属于group by的字段的话，sql语句就会报错。报错信息如下：> Expression #1 of SELECT list is not in GROUP BY clause and contains> nonaggregated column '数据库名.表名.字段名' which is not functiona_this is incompatible with sql_mode=only_full_group_byhttps://blog.csdn.net/u012660464/article/details/113977173

解决办法

长期解决方案 - 修改mysql配置文件

windows+PHPStudy+MySQL5.7修改
D:\phpstudy_pro\Extensions\MySQL5.7.26\my.ini

找到组[mysqld]  （不是[mysql]）

在组最后加一行

sql_mode=STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_ENGINE_SUBSTITUTION

保存，重启电脑，即可