MySQL and PostgreSQL aren't in the same ball park as Mongo. It's irrelevant.
Based on merits, architecture, and implementation Riak handily beats several of the DBs listed. It's a glaring omission and not the only one. As many chose Other as did Oracle.
Based on merits, architecture, and implementation Riak handily beats several of the DBs listed. It's a glaring omission and not the only one. As many chose Other as did Oracle.