Appendix B. Neo4j

This appendix provides a concise onboarding to Neo4j, the graph database used throughout the book, while emphasizing that the concepts and code generalize to other graph systems. It outlines why Neo4j was chosen—longstanding expertise, native graph capabilities, and an active community—and introduces its Community and Enterprise editions. The overview highlights Neo4j’s labeled property graph model, native index-free adjacency storage, Cypher query language, and developer workbench, along with full ACID transactions, strong recoverability, clustering for high availability, and capacity that scales to extremely large graphs.

Readers are guided through practical ways to get Neo4j running: downloading the server edition (with simple start-up steps and a browser-based interface), using the Desktop application to manage local and remote databases, or opting for Docker and the managed cloud service. The appendix recommends the free Community Edition for learning and notes that local installations are ideal for running the book’s code and exercises. Desktop streamlines common tasks such as creating projects, provisioning local DBMSs, starting instances, and opening the Neo4j Browser.

The appendix introduces Cypher as an easy-to-learn, declarative, pattern-based language for reading and writing graph data, and notes its broader adoption via openCypher. It then explains how Neo4j can be extended with plugins, focusing on two essential libraries: APOC, a comprehensive set of utility procedures and functions, and the Graph Data Science library, which provides scalable graph algorithms for analytics. Installation can be done by placing plugin files in the plugins directory and enabling them in the configuration, or through one-click setup in Desktop. It closes with handy maintenance tips, including using APOC to clear all data and drop constraints, preparing readers to run the book’s examples with a clean environment.

Figure B.1 DB-Engines ranking of Graph DBMSs

Figure B.2 An image of the Neo4j browser

Figure B.3 Saving the Neo4j Desktop app on a MacOS

Figure B.4 Launching the Neo4j Desktop

Figure B.5 Creating a new project in the Neo4j Desktop

Figure B.6 Adding and selecting a new local graph or connecting to an existing one

Figure B.7 Entering a graph name and password. In the case of a new local graph, create an admin password.

Figure B.8 Starting the new database instance

Figure B.9 Opening the Neo4j Browser

Figure B.10 APOC installation from the Neo4j Desktop

Figure B.11 GDS installation from the Neo4j Desktop

FAQ

MATCH (p:Person)
RETURN p

dbms.security.procedures.unrestricted=apoc.*,gds.*
dbms.security.procedures.allowlist=apoc.*,gds.*

CALL dbms.procedures() YIELD name
WHERE name STARTS WITH "apoc"
RETURN name

RETURN gds.version()

CALL apoc.periodic.iterate(
  'MATCH (n) RETURN n',
  'DETACH DELETE n',
  {batchSize:1000}
)

CALL apoc.schema.assert({}, {})