mysql异常ERROR 1055 (42000)说明

具体异常信息如下：

ERROR 1055 (42000): Expression #1 of SELECT list is not in GROUP BY clause and contains nonaggregated column 'aaa.test.age' which is not functionally dependent on columns in GROUP BY clause; this is incompatible with sql_mode=only_full_group_by

执行这样的SQL语句可重现异常 select age, name from test group by name

mysql5.1，不报异常

mysql5.5，不报异常

mysql5.6，不报异常

mysql5.7.22，报异常（具体从5.7哪个版本开始还没有确定下来，网上有人说5.7.5）

mysql从5.7的某个版本开始调整了默认参数sql_mode值为：

mysql> show variables like 'sql_mode';+---------------+-------------------------------------------------------------------------------------------------------------------------------------------+| Variable_name | Value                                                                                                                                     |+---------------+-------------------------------------------------------------------------------------------------------------------------------------------+| sql_mode      | ONLY_FULL_GROUP_BY,STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION |+---------------+-------------------------------------------------------------------------------------------------------------------------------------------+1 row in set (0.00 sec)mysql>

其中ONLY_FULL_GROUP_BY就是影响了上面SQL语句是否报异常

解决方法：

1、改写SQL语句，毕竟上面的写法不是标准的SQL语句

2、登陆mysql服务器，执行以下命令，在global与session级都修改

mysql> set global sql_mode='STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION';mysql> set session sql_mode='STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION';

3、结合第2种方法，在my.cnf文件中，指定sql_mode的值：

[mysqld]sql_mode=STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION

注：2与3结合可不用重启服务器，且即使重启配置也依然有效。