During maintenance on T150553, s51412__data was deleted. As I mentioned here: T127164 some databases are too large and create too much activity to provide any kind of redundancy, mistakes like this could happen, and I urged you to create backups and provided help to do that.
You mentioned you could recover those (T127164#2036868)- to help you with that, I have already recovered partially from an old copy from Sept 2015.
Apologies in advance for the disruptions, but we do have some constrained resources right now for tools databases (if you see the first task I mention, we run temporarily out of space for user databases), until we setup the new labsdb servers T140788.