Rewriting queries using views is a powerful technique that has applications in data integration, data warehousing and query optimization. Query rewriting in relational databases i...
With increasing amount of data being stored in XML format, OLAP queries over these data become important. OLAP queries have been well studied in the relational database systems. H...
Topological relationships like overlap, inside, meet, and disjoint uniquely characterize the relative position between objects in space. For a long time, they have been a focus of...
Unions of conjunctive queries, also known as select-project-join-union queries, are the most frequently asked queries in relational database systems. These queries are definable b...
Pervasive information systems give an overview of what digital environments should look like in the future. From a data-centric point of view, traditional databases have to be use...