How to Disable Strict SQL Mode in MySQL 5.7

If your app was written for older versions of MySQL and is not compatible with strict SQL mode in MySQL 5.7, you can disable strict SQL mode. For example, apps such as WHMCS 6 and Craft 2 do not support strict SQL mode.

If you're using WHMCS 7, see our article on customizing MySQL for WHMCS 7.

To disable strict SQL mode, SSH in to your server as root and create a new configuration file using nano or the editor of your choice:

sudo nano /etc/mysql/conf.d/disable_strict_mode.cnf

In the file, enter these two lines:


Save the file by pressing CTRL + X, then y, then ENTER to confirm changes.

Finally, restart MySQL with this command:

sudo service mysql restart

This change disables two SQL mode settings, STRICT_TRANS_TABLES and ONLY_FULL_GROUP_BY, that were added in MySQL 5.7 and cause problems for some older applications.

Confirming Strict SQL Mode Is Disabled

You can confirm strict SQL mode is disabled by running this command as root:

sudo mysql -i -BN -e 'SELECT @@sql_mode' | grep -E 'ONLY_FULL_GROUP_BY|STRICT_TRANS_TABLES'

If strict mode is disabled, you won't see any output from that command.

If disabling strict mode causes any problems for you, you can re-enable it by deleting that file and restarting MySQL again.

What Strict SQL Mode Errors Look Like

If your app isn't compatible with strict SQL mode, you'll often see SQL errors such as:

SQLSTATE[42000]: Syntax error or access violation: 1055 Expression #1 of
SELECT list is not in GROUP BY clause and contains nonaggregated column
'' which is not functionally dependent on
columns in GROUP BY clause; this is incompatible with sql_mode=only_full_group_by

Last updated: October 06, 2016