In a binary symmetric relationship, A is related to B if and only if B is related to A. Symmetric relationships between k participating entities can be represented as multisets of...
The relational data model is based on sets of tuples, i.e. it does not allow duplicate tuples in a relation. Many database languages and systems do require multi-set place, the hi...
Magic sets rewriting is a well-known optimization heuristic for complex decision-support queries. There can be many variants of this rewriting even for a single query, which diffe...
Praveen Seshadri, Joseph M. Hellerstein, Hamid Pir...
Abstract. OWL is a recommended language for publishing and sharing ontologies on the Semantic Web. To manage the ontologies, several OWL data management systems have been proposed....
Myung-Jae Park, Jihyun Lee, Chun-Hee Lee, Jiexi Li...
Query containment is a fundamental algorithmic problem in database query processing and optimization. Under set semantics, the query-containment problem for conjunctive queries ha...