CliqueSquare

CliqueSquare is a system for storing and querying large RDF graphs relying on Hadoop's distributed file system (HDFS) and Hadoop's MapReduce open-source implementation. CliqueSquare is equipped with a unique optimization algorithm capable of generating highly parallelizable flat query plans relying on n-ary equality joins. In addition, it provides a novel partitioning and storage scheme that permits first-level joins to be evaluated locally using efficient map-only joins.