Defining Referential Integrity Constraints in Graph-oriented Datastores

Nowadays, the volume of data manipulated by our information systems is growing so rapidly that they cannot be efficiently managed and exploited only by means of standard relational data management systems. Hence the recent emergence of NoSQL datastores as alternative/complementary choices for big data management. While NoSQL datastores are usually designed with high performance and scalability as primary concerns, this often comes at a cost of tolerating (temporary) data inconsistencies. This is the case, in particular, for managing referential integrity in graph-oriented datastores, for which no support currently exists. This paper presents a MDE-based, tool-supported approach to the definition and enforcement of referential integrity constraints
(RICs) in graph-oriented NoSQL datastores. This approach relies on a domain-specific language allowing users to specify RICs as well as the way they must be managed. This specification is then exploited to support the automated identification and correction of RICs violations in a graph-oriented datastore. We illustrate the application of our approach, currently implemented for Neo4J, through a small experiment.