Are there any implementations, api or examples of OrientDB and C#. The reason I am looking at OrientDB is becuase it\'s the only one that I found that is a combination of Graph
Regarding your second question on RavenDB, it doesn't have "joins" like in the relational sense but you can always store references to other documents by storing it's document id field. Here is the join question in the FAQ. One of the suggestions they give is to denormalize (store more than just the Id of the related document) which can be a big trade-off to make.