RDF on Cloud Number Nine
نویسندگان
چکیده
We examine whether the existing ’Database in the Cloud’ service SimpleDB can be used as a back end to quickly and reliably store RDF data for massive parallel access. Towards this end we have implemented ’Stratustore’, an RDF store which acts as a back end for the Jena Semantic Web framework and stores its data within the SimpleDB. We used the Berlin SPARQL Benchmark to evaluate our solution and compare it to state of the art triple stores. Our results show that for certain simple queries and many parallel accesses such a solution can have a higher throughput than state of the art triple stores. However, due to the very limited expressiveness of SimpleDB’s query language, more complex queries run multiple orders of magnitude slower than the state of the art and would require special indexes. Our results point to the need for more complex database services as well as the need for robust, possible query dependent index techniques for RDF.
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