Hi trilefile (there is ALWAYS time for a introducing welcome line, if you start a new thread. Thats important especially if you are asking for help from a community board. It's a matter of politeness),
trilefile wrote:Is it possible to use the built-in XAMPP phpMyAdmin interface to log into a remote MySQL server
That depends on the configuration of your hoster.
Most hosters don't permit remote connections to the databases.
trilefile wrote:or must I download and install a separate copy of phpMyAdmin?
Most hosters provide a database administration tool by theirself and very common that is an instance of phpmyadmin too.
You should ask your hoster what they think the best way is to connect to the database.