7 years later, 50 upvotes but only 1 decent answer. There must be some syncronisation patterns or best practices out there?

Thanks, I think you're talking about distributed dbs with the same schema and dealing with distributed transactions. I'm thinking more of scenarios where the two DBs are completely autonomous (e.g. they assign unique ids in completely different ways and the schemas differ) but you want to sync a subset of the data in them.