We study the problem of answering queries posed on virtual views of XML documents, a problem commonly encountered when enforcing XML access control and integrating data. We approa...
We study the data complexity of instance checking and conjunctive query answering in the EL family of description logics, with a particular emphasis on the boundary of tractability...
Recent work on weighted-pushdown systems shows how to generalize interprocedural-dataflow analysis to answer “stack-qualified queries”, which answer the question “what data...
In this paper we consider the on-line max and min query auditing problem: given a private association between fields in a data set, a sequence of max and min queries that have alr...
Abstract. Increasing the number of peers in a peer-to-peer network usually increases the number of answers to a given query as well. While having more answers is nice in principle,...
Wolfgang Nejdl, Wolf Siberski, Uwe Thaden, Wolf-Ti...