It's a little boring to talk about... but it's not boring at all when something happens to your database records. It can happen in a moment... as I discovered when I accidentally dropped my external back-up drive last Friday. "No problem," I thought. "It was a short fall onto carpeting... and it's a well-built drive. Haven't I knocked it around a little before?"
My drive experienced the event differently. When I plugged it in (so as to access all of the photos that I use in my work) it made little grunting sounds and disappeared from the computer explorer memory. If you've been there yourself, you know what I did next... a series of restarts, re-plug-ins, and re-trys all gave me the same result. Yes, it was true, about 10 years worth of raw and edited photos were no longer accessible.