Perhaps the intention is to run on a user database,
and "model" was chosen as an example.
If I'm following this, the specific statement is
looking for the file names in the filesystem that
contain the database data, and I wonder why you'd
want that from "model", which only exists so that
you can say "create database" and make a copy of it,
maybe on different filesystems. You would want to
back up model, I suppose. (People do that for me. :-)
(...I hope.)