On Unix, the MySQL server mysqld can be started and run by any user. To change mysqld to run as a normal unprivileged Unix user user_name, you must do the following:
Stop the server if it’s running (use mysqladmin shutdown).
Change the database directories and files so that user_name has privileges to read and write files in them (you might need to do this as the Unix root user):
shell> chown -R user_name /path/to/mysql/datadir
If you do not do this, the server will not be able to access databases or tables when it runs as user_name.
If directories or files within the MySQL data directory are symbolic links, you’ll also need to follow those links and change the directories and files they point to. chown -R might not follow symbolic links for you.
Start the server as user user_name. If you are using MySQL 3.22 or later, another alternative is to start mysqld as the Unix root user and use the –user=user_name option. mysqld starts up, then switches to run as the