Anyone who noticed ... the DB restarted again just now.
This is the same cause as the other day.
No mining is affected.
I've not applied the fix yet - though the problem has existed for years, just unlucky I guess it's happened twice in a few days.
Mine on!

Edit: KanoDB reload completed at 06:16:47 UTC
Each time this happens the CKPool Status app on my phone says that we found a block.