he LUPOSDATE SPARQL system supports various approaches to manage RDF data and process SPARQL queries: Index, RDF3X, Stream, Jena and Sesame. Jena [21] and Sesame [3] refer to third-party SPARQL engines. Index is our in-memory Engine presented in [6]. Stream is our stream-based implementation (see [10]). RDF3X is a re-implementation of [14], but is further enhanced with additional optimization strategies.
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