Does restarting my Nginx service in Ubuntu affect the mysql service? an example would be, if I stop the nginx service, would the traffic to website stop and the mysql database/service still work?
I would appreciate any help
The MySQL service its self will continue to run, so if you are using it via CLI, or a remote connection that will not be interrupted.
However if you were for example using a PHP script which was being run by nginx and had an open connection to MySQL, that connection could be terminated and the user may get some kind of error.