2 ms·

Auto-incrementing integers mean you're always dependent on a central server. UUIDs break that dependency, so you can scale writes up to multiple databases in pa

• sgarland 3y ago
  If the DB fails to assign an ID, it's probably broken, so having an external ID won't help you. If you're referring to not having conflicts between distributed nodes, that's a solved problem as well – distribute chunked ranges to each node of N size.
  • kiitos 3y ago
    Whatever is distributing the chunks is still a point of central coordination.
    • Dylan16807 3y ago
      Yes, and? If you can't manage minor levels of coordination because your database is on fire, the problem is that your database is on fire.
      • kiitos 3y ago
        Fewer points of coordination is always better. In general you shouldn't need to make a roundtrip to produce an ID.
        • Dylan16807 3y ago
          > Fewer points of coordination is always better. The distributed database needs a coordination system anyway, so it's not an additional point. > In general you shouldn't need to make a roundtrip to produce an ID. Did you forget the context over the last week? We're already talking about reserving big chunks to remove the need to make a roundtrip to produce an ID. There would instead be something like one roundtrip per million IDs.
          • kiitos 3y ago
            > The distributed database needs a coordination system anyway, so it's not an additional point. Nope! Distributed databases do not necessarily need a "coordination system" in this sense. Most wide-scale distributed databases actually cannot rely on this kind of coordination. > Did you forget the context over the last week? We're already talking about reserving big chunks to remove the need to make a roundtrip to produce an ID. There would instead be something like one roundtrip per million IDs. OK, it's very clear that you're speaking from a context which is a very narrow subset of distributed systems as a whole. That's fine, just please understand your experience isn't broadly representative.
            • Dylan16807 3y ago
              > Nope! Distributed databases do not necessarily need a "coordination system" in this sense. Most wide-scale distributed databases actually cannot rely on this kind of coordination. I'm assuming a system that tracks nodes and checks for quorum(s), because if you let isolated servers be authoritative then your data integrity goes to hell. If you have that system, you can use it for low-bandwidth coordinated decisions like reserving blocks of ids. Am I wrong to think that most distributed databases have systems like that? > OK, it's very clear that you're speaking from a context which is a very narrow subset of distributed systems as a whole. That's fine, just please understand your experience isn't broadly representative. Sure, but the first thing you said in this conversation was "Whatever is distributing the chunks is still a point of central coordination." which is equally narrow, so I wasn't expecting you to suddenly broaden when I asked why that mattered.
              • kiitos 3y ago
                > I'm assuming a system that tracks nodes and checks for quorum(s) Not sure why. > because if you let isolated servers be authoritative then your data integrity goes to hell Many AP systems maintain data integrity without central authorities or quorums for data. > Am I wrong to think that most distributed databases have systems like that? No, not wrong! Just that it's one class of distributed systems, among many.
• akvadrako 3y ago
  The way to solve that is giving each server it's own range of IDs.