Former VoltDB developer here. John makes some good technical arguments about why implementing transactional SQL on top of a distributed KV store (even a transa

Former VoltDB developer here. John makes some good technical arguments about why implementing transactional SQL on top of a distributed KV store (even a transactional one) is hard. The points about metadata performance and consistency were actually new ideas to me. I already had beef with moving the data around to SQL nodes as that is an obvious waste of capacity. But the importance of metadata in processing SQL queries in a distributed database never occurred to me even though I've lost a decent chunk of my life implementing that consistency. It's one of those things you take for granted if it's how you have always done it.