Well, restoring the old database file and importing the (few) changes from the intervening 8 days seems to have been a reasonable solution, and I've written a new procedures document to try and avoid doing any of the things that we could think of that might have caused the problem. Thank $deity for backups, eh. Rest of the day's been quite unproductive, and interrupted by my co-worker getting me to help her move stuff. Still, I've got another hour to show something useful!
