Abstract

In this paper we consider how to integrate a simple and developer-friendly data model such as the property graph with more complex and less user-friendly data models such as relational database tables. We observe that algebraic data types are a common foundation of most enterprise schema languages we deal with in practice, and are also a suitable basis for a property graph formalism. We introduce this formalism in terms of type theory, algebra, category theory, query processing and data migration theory; it has clear connections to relational database theory programming language theory and graph theory. The approach is simple, flexible, implementable in practice on top of different backends (including traditional RDBMSs) while guaranteeing semantic consistency across supported languages and datasets.