[CRConrad]

But you can't just put

   ...tp://my_site/some_dir/any_sqlite_file.db

in an URL and expect a user's browser to display something sensible like it would with an HTML file (or even a fixed-format text data file). You need a process on your server that translates the content in the database to browser-readable HTML.

So in the sense of "put up a website by just transferring static files", an Sqlite database isn't quite "a flat file". It's a single file, yes; but its content is "bumpy" -- not "flat".

(Then again, once you have that translate-content-to-HTML process installed on your Web server, updating the content is reduced to just transferring a new .db file to it.)