One thing that is still being developed for graph databases is integrity constraint (IC) support. One possibility to IC proposal is to consider a graph conceptual schema and a graph database schema.
At least inherent ICs coming from a graph conceptual schema should be considered as explicit ICs on the graph databases level, i.e., using a DDL. In the paper, we focus on graph database Neo4j and its possibilities to express a database schema and ICs.
We extend these possibilities through new constructs in Neo4j DDL including their prototype implementation and experiments.