Query Rewriting for Incremental Continuous Query Evaluation in HIFUN

Incremental Query Rewriting for OWL 2 QL

Query rewriting under query refinements

Ontologies expressed in Description Logics or extensions of Datalog are gradually used for describing the domain of many research and industrial strength applications. They provide a formal semantically rich and data-independent layer over which user queries can be posed. A prominent technique for query answering in ontology-based applications is query rewriting, where the given user query Q an...

Geomodification in Query Rewriting

Web searchers signal their geographic intent by using placenames in search queries. They also indicate their flexibility about geographic specificity by reformulating their queries. We conducted experiments on geomodification in query rewriting. We examine both deliberate query rewriting, conducted in user search sessions, and automated query rewriting, with users evaluating the relevance of ge...

Implementing Query Rewriting for Consistent Query Answering in Databases

For several reasons, databases may be inconsistent with respect to a set of integrity constraints. Those inconsistent states must be somehow resolved in order to be able to use the information stored in them. In some cases, data cleaning could be an approach to get rid of these inconsistencies. However, this may be a complex and nondeterministic process that may lead to the loss of potentially ...

Continuous Constraint Query Evaluation for Spatiotemporal Streams

In this paper we study the evaluation of continuous constraint queries (CCQs) for spatiotemporal streams. A CCQ triggers an alert whenever a configuration of constraints between streaming events in space and time are satisfied. Consider, for instance, a server that receives updates from GPS-enabled agents that report their positions and other measurements (e.g., environmental readings). An exam...