First, everything is a tradeoff. Do not expect to have a cake and eat it too. Secondly, thiese are indeed two different levels. A database that serves as a sin

First, everything is a tradeoff. Do not expect to have a cake and eat it too. Secondly, thiese are indeed two different levels. A database that serves as a single source of truth can be implemented as an entire cluster of serves with no single point of failure.. At least in theory ;)