I'm new to OrientDB and I just started to experiment with its GUI. Now I encountered a non-intuitive behavior and I'm not sure whether it is a bug or it is only my limited understanding.
In the initial setup, OrientDB had a vertex "V". I am able to create new vertices in the graph editor:
However, if I rename the vertex "V" or create another vertex ("EAN-Key"), it is not possible to select it. The only option in the dialog is "V" (or nothing if I rename "V" in the Schema Manager of the GUI and rebuild all indexes).
In the logs, I see this error message:
2015-08-20 15:40:05:713 SEVERE Internal server error:d request: sql.hjava.lang.IllegalArgumentException: Class 'EAN-Key' is not an instance of V [ONetworkProtocolHttpDb]
Is there something special about "V"? I cannot see any difference in the "Schema Manager". I did not find any information in the documentation, too.
"V" is the base class for vertices. This is a convention. If you want to create your own Vertex Types, just create a class that extends "V". The same is for edges where the name is "E".