We study in this paper provenance information for queries with aggregation. Provenance information was studied in the context of various query languages that do not allow for aggr...
We introduce a representation system for relational data based on algebraic factorisation using distributivity of product over union and commutativity of product and union. We giv...
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...
In this survey paper we give an intuitive treatment of the discrete time quantization of classical Markov chains. Grover search and the quantum walk based search algorithms of Amba...
We present a formal framework for capturing the provenance of data appearing in XQuery views of XML. Building on previous work on relations and their (positive) query languages, w...