That's one way if you're using sequences to generate ids. If you're encoding information in UUIDs, you also have to take into account how many bits you want to

That's one way if you're using sequences to generate ids. If you're encoding information in UUIDs, you also have to take into account how many bits you want to allocate to the database (shard) id. One method I've used is to hard-code the shard id as the return value in a function: effectively a constant. (Edit to add: This serves the same purpose as setting the starting offset of the sequence.) You do have a bit of custom code on each database instance in this case, which is its own tradeoff.