Group by query errors on mysql upgrade from mysql 5.6 to mysql 5.7

login as root or sudo to edit mysql configuration file

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

#vi /etc/my.cnf

Add following line to the bottom of file

sql_mode = STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,

NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION

Restart mysql server