On the SitePoint PHP blog they've posted a tutorial from author Tobias Nyholm introducing the Neo4j bundle for Symfony-based application. This bundle provides functionality to work with Neo4j graph databases natively in the application.
There is no such thing as disconnected information, no matter where you look – people, events, places, things, documents, applications and the information about them is all heavily connected. As the volume of data grows, so does the number and dynamicity of its connections. And if you’ve tried in the past to store and query that highly connected, semi-structured data in any database, you probably experienced a lot of challenges.
The tutorial talks some about graph databases, how they work and what kind of data fits into them best. It also briefly covers the Cypher Query Language followed by an introduction to the bundle and what it has to offer. Code examples of putting the bundle to use for queries are provided including the models to handle the results, relationships and an example application you can use to start with a working example.