Now my site's down! Looks like a total server or DNS failure rather than a database error.
(edit) Yep, I can't even log onto CPanel or access my secondary domain, so the server appears to be down.
That said, I can't access my.xilo.net to check the status of my hosting services, so that begs the question - is somebody attacking Xilo?
(edit2) Just found a list of servers which are undergoing maintenance and mine's one of them. Sorry to have caused a panic, nobody's attacking Xilo.