Depending on how mysql was installed onto mac os x can depend on how to restart the service. the “/Library” directory is a good place to start. If one can’t find it there another good place to check is “/usr/share/mysql/mysql.server”
If the executable exists in this location the mysql service can be restarted as follows:
Be sure to check the mysql process id to be sure that the timestamp for the restart matches. Also check the logfiles for any errors.