A class diagram is a tree that describes the structure of an application. A Tree is just a specialized form of a Graph so why not use a graph database to store a class diagram and analyze it? In this post we will build a graph in OrientDB that contains OrientDB 2.0.6 class diagram. Classes and interfaces will be the vertices of our graph while the edges describe relationships superclassOf and usedBy. So we will use the created graph to analyze the classes and relations between them, by exploiting SQL.