Microsoft are NGMI, there is nothing rare or hard about SQL. Proof of stake works because people with a bunch of underlying token risk it to the protocol to create new blocks, it incentivises good behaviour. Proof of work works because it requires your time and effort to add a new block, again the good behaviour is incentivised, this is not so for Proof of SQL where nothing is rare or any work is done to protect the system. Further in order to build a trustless system it needs to be decentralised, something Microsoft haven't a clue about. This endeavour will just be declared a failure 6 months from now.