> Since this is fairly off-topic at this point, I'll keep it short. The > simple > rule for Dynamo goes like this: if (R+W>N && W>=Quorum), then you're > guaranteed a consistent result always. You get eventual consistency if > W>=Quorum. If W<Quorum, then you can get inconsistent data that must be > detected/fixed by readers (often using timestamps or similar techniques). > Joe is right, enforcing (W=3, R=1, N=3) on a Dynamo system gives the same > (provably identical?) behaviour as HBase, with respect to consistency. > > For those interested in a comparison of the consistency behavior, there's an older, but really excellent thread on quora with detailed analysis: http://www.quora.com/How-does-HBase-write-performance-differ-from-write-performance-in-Cassandra-with-consistency-level-ALL
Don't miss the last answer in the the thread. It's unfortunately collapsed due to some quora policy, but it contains some of the best details.
