To restart the MySQL server on a Linux or Unix system over an SSH connection, you can use the following command:
sudo service mysql restart
This command uses the sudo command to run the service command with superuser privileges. The service command is used to manage system services, and the mysql argument specifies the MySQL service. The restart argument is used to restart the MySQL service.
Note: The exact command to restart the MySQL service may vary depending on the Linux distribution and the MySQL version installed. If the above command does not work, you may need to use a different command, such as sudo systemctl restart mysql or sudo /etc/init.d/mysql restart.