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sql>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
sql">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';