When we started Graphviz, we vaguely sensed the potential for graph databases or environments, like neo4j, but we didn't work much in that area. It would take more resources, or intensity, than what we had. Anyway, gvpr is a modest attempt at a sort of graph query language.

Neo4J is interesting. It does something important, mainly, rationalize the mess of graph representations and algorithms. It's not hard to understand why that is valuable, but Neo4J sell it as being "efficient for linked structures" (relational databases don't have foreign keys and indices) and "intuitive" (have you ever tried to read the code for graph matching in Cymbal? I rest my case.) They have investments of hundreds of millions? Worth billions? They contributed something valuable to the tech economy.

It's surprising the conventional relational database products don't pay much attention to this opportunity, but they have gone vertical, e.g. credit card processing, because in the end it's more profitable to solve big end customer problems.