Graph Databases

Chapter 3. Data Modeling with Graphs

In previous chapters we’ve described the substantial benefits of the graph database when compared both with document, column family, and key-value NOSQL stores, and with traditional relational databases. But having chosen to adopt a graph database, the question arises: how do we model the world in graph terms?

This chapter focuses on graph modeling. Starting with a recap of the property graph model—the most widely adopted graph data model—we then provide an overview of the graph query language used for most of the code examples in this book: Cypher. Cypher is one of several languages for describing and querying property graphs. There is, as of today, no agreed-upon standard for graph query languages, as exists in the relational database management systems (RDBMS) world with SQL. Cypher was chosen in part because of the authors’ fluency with the language, but also because it is easy to learn and understand, and is widely used. With these fundamentals in place, we dive into a couple of examples of graph modeling. With our first example, that of a systems management domain, we compare relational and graph modeling techniques. With the second example, the production and consumption of Shakespearean literature, we use a graph to connect and query several disparate domains. We end the chapter by looking at some common pitfalls when modeling with graphs, and highlight some good practices.

Models and Goals

Before we dig deeper into modeling with graphs, ...