Abstract— This paper presents our work on supporting flexible query evaluation over large distributed, heterogeneous, and autonomous sources. Flexibility means that the query ev...
An effective query optimizer finds a query plan that exploits the characteristics of the source data. In data integration, little is known in advance about sources' propertie...
Location-based spatial queries (LBSQs) refer to spatial queries whose answers rely on the location of the inquirer. Efficient processing of LBSQs is of critical importance with the...
The Web has evolved from a global information space of linked documents to a web of linked data. The Web of Data enables answering complex, structured queries that could not be an...
We observe two deficiencies of current query processing and scheduling techniques for sensor networks: (1) A query execution plan does not adapt to the hardware characteristics o...