These databases already exist. Typically the way it works is after you claim an identity, they will look up past addresses, phone numbers or employers then pres

These databases already exist. Typically the way it works is after you claim an identity, they will look up past addresses, phone numbers or employers then present multiple choice questions asking which one is part of your past. The companies I've seen that do these are not hosting (or claim to not host) any of the data, but rather have hooks to fetch it from financial institutions. I think it's mostly credit bureaus, but could also be banks.