&gt; There is as yet no absolute challenger to the relational model. When people think database, they still think SQL. But if there is a true challenger, it is in the graph model. Because graph data structures power social networks, and social networks are the dominant technological organism of the era.<p>You can use a fact database model (like Datomic&#x27;s) and then you don&#x27;t have to choose between row, column, document and graph based databases, those are projections on top of some index.<p>If entities are universally unique and attributes namespaced you can get a &quot;database of everything&quot;. Or you need at least a mapping between entities from different vendors. That&#x27;s the hard part :)