How to clear the cache of the downloaded file on the site?

Question

HTML

We update the file on the site, by clicking the download button it is downloaded.
Normal html page.
The bottom line is that when we update the file, the old one is downloaded from the page. Only clearing the cache helps.
Users will not clear the cache themselves every time, what should we do?

Answer 1

Either send headers with the file that prohibit caching ( Cache-Control: no-cache), or add a random string to the address as a parameter ( http://example.com/file.name?45qdf).