Graph databases and how to use them

Graph models tend to be quite large when they are populated with node and edge data describing a real system, community, or process. This data can be stored on a local filesystem and loaded as needed by analysis tools, but eventually the file becomes so large that loading and processing time required makes this impractical. Fortunately there are databases that natively store data as graphs. These are general-purpose graph databases which are able to accommodate arbitrary graph data, unlike specialized graph databases like triplestores. In this chapter, we will look at several graph databases along with some of their core features, their query and path traversal languages, and their administrative and query interfaces. Finally, we will look at some graph database APIs, which enable programmers to write graph-based software applications that can query, traverse, analyze, and manipulate graph data.