Dgraph isn’t an RDF triple store. We allow RDFs to be parsed, just because of the wide data availability – but are switching over to JSON data input; something that most developers are familiar with.
In terms of traversal, the way we store our data, the traversal happens in O(1) time. All the outgoing edges are stored in a posting list, which is stored as a value. So, to find all the nodes connected to a given node, is just a key lookup for us.
Shortest path uses this as well. In fact, super fast traversals and intersections are the key designs of Dgraph.