Interactive Query Processing for Linked Data

Abstract. In the recent years, the concept of publishing data on the Internet us-ing the Linked Data principles has gained more and more widespread acceptance. A plethora of novel applications are conceivable, which share the need for retriev-ing data from the “Linked Data cloud”. However, though the process of publish-ing Linked Data is straightforward, data retrieval poses a significant challenge. The location of data relevant to a query is generally unknown. While one could cache the entire cloud on a single system, an on-demand query processing ap-proach is necessary to handle dynamic data. We have designed, implemented, and evaluated such an approach using a breadth-first retrieval process to execute SPARQL queries over the Linked Data cloud. Special care was taken to support interactive applications, which depend on displaying results to users quickly.