Efficient one-pass computation of F0, the number of distinct elements in a data stream, is a fundamental problem arising in various contexts in databases and networking. We consid...
Given a region qR and a future timestamp qT, a "range aggregate" query estimates the number of objects expected to appear in qR at time qT. Currently the only methods fo...
Sensor networks attract increasing interest, for a broad range of applications. Given a sensor network, one key issue becomes how to utilize it efficiently and effectively. In par...
Extraction-Transformation-Loading (ETL) tools are pieces of software responsible for the extraction of data from several sources, their cleansing, customization and insertion into...
Alkis Simitsis, Panos Vassiliadis, Timos K. Sellis
Order-based element labeling for tree-structured XML data is an important technique in XML processing. It lies at the core of many fundamental XML operations such as containment j...
SNAP is a novel high-performance snapshot system for object storage systems. The goal is to provide a snapshot service that is efficient enough to permit "back-in-time" ...
Replicating data over a cluster of workstations is a powerful tool to increase performance, and provide faulttolerance for demanding database applications. The big challenge in su...
Moving objects databases managing spatial objects with continuously changing position and extent over time have recently found large interest in the database community. Queries ab...