Query containment is a fundamental algorithmic problem in database query processing and optimization. Under set semantics, the query-containment problem for conjunctive queries ha...
We study containment and equivalence of (unions of) conjunctive queries on relations annotated with elements of a commutative semiring. Such relations and the semantics of positiv...
The problems of query containment, equivalence, and minimization are recognized as very important in the context of query processing, specifically of query optimization. In their...
In data applications such as information integration, there can be limited access patterns to relations, i.e., binding patterns require values to be specified for certain attribut...