I work with CouchDB, and it sounds similar: many queries end up being map-reduce functions run across many CouchDB &quot;databases&quot; (partitions) on the same node&#x2F;cluster.<p>One of the nice things about this approach, from my CouchDB experience, is that each DB&#x2F;partition has its own permissions (fully extensible through design-documents shoved into that DB), so instead of needing to carefully write your business layer to ensure that users can only ever query their own data out of a table, you just do all your work for a particular user in a table that only contains stuff that user has a right to access to begin with.<p>It&#x27;s a lot like working with S3 buckets, now that I think about it. Buckets containing tables, rather than buckets containing objects.