Answering queries using views

IMGpedia is a linked dataset that provides a public SPARQL endpoint where users can answer queries that combine the visual similarity of images from Wikimedia Commons and

– As we are using a kind of “how”-provenance modeled using semirings, we can map the general semiring to more specific ones that capture different ways in which the

We recently identified such query languages which are both expressible in Datalog and in monadic second-order logic while subsuming expressive query for- malisms such as monadic

This gives rise to the notion of aggregate certain answers, which can be explained as follows: a number is an aggregate certain answer to a counting query over a knowledge base if

In this paper, we present a sound and complete algorithm for answering SPARQL queries under the OWL 2 Direct Semantics entailment regime (from now on, SPARQL-OWL), describe

We use SPARQL conjunctive queries as views that describe sources contents. As in the Bucket Algorithm [20], relevant sources are selected per query subgoal, i.e., triple pattern.

Abstract. We present an idea of efficient query answering over an RDF dataset employing a consumer-grade graphic card for an efficient com- putation. We consider tree-shaped

We apply this idea to model the preferences of query answers indirectly, by modeling the preferences over the contexts that entail them.. In a nutshell, we divide an EL knowledge