Incompatible with sql_mode=only_full_group_by Permanent solution

If a query has aggregate functions and no GROUP BY clause, it cannot have nonaggregated columns in the 

select list, HAVING condition, or ORDER BY list with ONLY_FULL_GROUP_BY enabled.

Some people try this for disable it but it's not good at all.

This is not good.

SET sql_mode = ''

Better solution is blew code.

SET GLOBAL sql_mode=(SELECT REPLACE(@@sql_mode,'ONLY_FULL_GROUP_BY',''));

The permanent  solution

We open the configuration file we decided on before (/etc/mysql/my.cnf) and add the following line into the [mysqld]section

sql_mode = "STRICT_TRANS_TABLES,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION"

Save, exit, and restart MySQL