Real-Time RSS feed

I have an RSS feed written in ColdFusion that is currently scheduled (in CF Administrator) to update every 3 hours. Instead, I plan to have it update every time a new document is added to our database.

The difficulty I see is that the ColdFusion file that creates the feed writes it to a single XML document. That means if I add a document at 1:00 p.m., and the next one at 1:15 p.m., the second overwrites the first. If a consumer doesn’t have his/her RSS feed reader to be reading continuously, doesn’t he/she run the risk of missing lots of new documents?

Advice would be greatly appreciated! –diane