Comment by dapperdrake
5 days ago
Transactions and a single consistent source of truth with stuff like observability and temporal ordering is centralized and therefore "over there" for almost every place you could be in.
As long as communications have bounded speed (speed of light or whatever else) there will be event horizons.
The point of a database is to track changes and therefore time centrally. Not because we want to, but because everything else has failed miserably. Even conflicting CRDT change merges and git merges can get really hairy really quickly.
People reinvent databases about every 10 years. Hardware gets faster. Just enjoy the show.
I haven't used Datomic, but you're right that the part that requires over there is "single consistent source of truth." There's only ever a single node that is sequencing all writes. Perhaps as a result of this, it provides strong [verified ACID guarantees][1].
What I got from Hickey's talk is that he wanted to design a system that resisted the urge to encode everything in a stored procedure and run it on the database server.
[1]: https://jepsen.io/analyses/datomic-pro-1.0.7075