Recently performed the necessary SQL queries and noticed the following error:
ERROR 1055 (42000): Expression #4 of SELECT list is not in GROUP BY clause and contains nonaggregated column 'database_name.table_name.column_name' which is not functionally dependent on columns in GROUP BY clause; this is incompatible with sql_mode=only_full_group_by
To solve the error, connect to the mysql server:
mysql -u root -p
Execute a query that displays the values of sql_mode:
show variables like 'sql_mode';
At me it was displayed:
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
Copy the string with these values, remove “ONLY_FULL_GROUP_BY” and execute the query:
SET sql_mode='STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION';
By this request, we disabled “ONLY_FULL_GROUP_BY” and after that the error will not be displayed.
So that this error does not appear later, we exit mysql:
exit
Open the MySQL configuration file, for example, in the text editor nano (Ctrl + X for exit, y/n for saving or canceling changes):
sudo nano /etc/mysql/mysql.conf.d/mysqld.cnf
I did not have sql_mode= in the file, so at the end of the file I inserted the line with the previously copied values, removing from it ONLY_FULL_GROUP_BY, in my case, the following happened:
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 to apply the changes:
sudo service mysql restart
Done.