Ephedra: SPARQL Federation over RDF Data and Services
نویسندگان
چکیده
Knowledge graph management use cases often require addressing hybrid information needs that involve a multitude of data sources, a multitude of data modalities (e.g., structured, keyword, geospatial search), and availability of computation services (e.g., machine learning and graph analytics algorithms). Although SPARQL queries provide a convenient way of expressing data requests over RDF knowledge graphs, the level of support for hybrid information needs is limited: existing query engines usually focus on retrieving RDF data and only support a set of hard-coded built-in services accessible via SPARQL 1.1 queries. To deal with this problem, we present Ephedra: a SPARQL federation engine aimed at processing hybrid queries, which provides a flexible declarative mechanism for including hybrid services into a SPARQL federation.
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