MySQL：this is incompatible with sql_mode=only_full_group_by

错误场景

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 functionally dependent
on columns in GROUP BY clause; this is incompatible with
sql_mode=only_full_group_by

解决方案

这是临时的解决方案，要最终解决需要修改配置文件

SET @@global.sql_mode ='STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_ENGINE_SUBSTITUTION';
SET sql_mode ='STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_ENGINE_SUBSTITUTION';