Titan is a graph database that was developed by Aurelius (http://thinkaurelius.com/). The application source and binaries can be downloaded from GitHub (http://thinkaurelius.github.io/titan/), and this location also contains the Titan documentation. Titan has been released as an open source application under an Apache 2 license. At the time of writing this book, Aurelius has been acquired by DataStax, although Titan releases should go ahead.
Titan offers a number of storage options, but I will concentrate only on two, HBase—the Hadoop NoSQL database, and Cassandra—the non-Hadoop NoSQL database. Using these underlying storage mechanisms, Titan is able to provide a graph-based storage in the big data range.
The TinkerPop3-based Titan release 0.9.0-M2 was released in June 2015, which will enable greater integration with Apache Spark (TinkerPop will be explained in the next section). It is this release that I will use in this chapter. It is TinkerPop that the Titan database now uses for...