Extensions to the Pig data processing platform for scalable RDF data processing using Hadoop

In order to effectively handle the growing amount of available RDF data, a scalable and flexible RDF data processing framework is needed. We previously proposed a Hadoop-based framework, which takes advantages of scalable and fault-tolerant distributed processing technologies, originally proposed as Google´s distributed file system and MapReduce parallel model. In this paper, we present a method extending the Pig data processing platform on top of the Hadoop infrastructure. Pig compiles programs written in a high level language, called Pig Latin, into MapReduce programs that can be executed by Hadoop. In order to support RDF, Pig was extended with the ability to load and store RDF data efficiently. Furthermore, as reasoning is an important requirement for most systems storing RDF data, support for inferring new triples using entailment rules was also added. In this paper, we describe these extensions and present an evaluation of their performance.