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arXiv · 1503.02940

Efficient Query Processing for SPARQL Federations with Replicated Fragments

Gabriela Montoya·Hala Skaf-Molli·Pascal Molli·Maria-Esther Vidal
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Abstract

Low reliability and availability of public SPARQL endpoints prevent real-world applications from exploiting all the potential of these querying infras-tructures. Fragmenting data on servers can improve data availability but degrades performance. Replicating fragments can offer new tradeoff between performance and availability. We propose FEDRA, a framework for querying Linked Data that takes advantage of client-side data replication, and performs a source selection algorithm that aims to reduce the number of selected public SPARQL endpoints, execution time, and intermediate results. FEDRA has been implemented on the state-of-the-art query engines ANAPSID and FedX, and empirically evaluated on a variety of real-world datasets.

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Gabriela Montoya, Hala Skaf-Molli, Pascal Molli, Maria-Esther Vidal. 2015-03-10. Efficient Query Processing for SPARQL Federations with Replicated Fragments. https://arxiv.org/abs/1503.02940

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