When you do the import - where does it go? How would you MANUALLY update the tables if you do it manually? I'm assuming, based on the initial post, that you are importing and then want to use some append or update queries to append or update records in different tables from that imported data. Is that correct?
If so, that is how you would "refresh" your tables - you would need to create a set of append and/or update queries to do the job. You can then have code set up to do the whole process. But we can't make too many suggestions at this point because we don't know what your process to import data is like and where it sends it, etc.