Access Database locks. Update file in real time

Just a question, if I have a database connected to a web site, where data is being read from the database, if I was to make an edit to the database at any time, and upload it over the current database, would I have any problems doing it this way?

If this is the wrong way to go, can someone please advise. Basically I wish to make changes and then update the file in real time, but dont want to have a problem with people viewing the site.

Please advise on any ideas you have. Thank you