Database Systems (TODS)


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ACM Transactions on Database Systems (TODS), Volume 36 Issue 2, May 2011

Relational languages and data models for continuous queries on sequences and data streams
Yan-Nei Law, Haixun Wang, Carlo Zaniolo
Article No.: 8
DOI: 10.1145/1966385.1966386

Most data stream management systems are based on extensions of the relational data model and query languages, but rigorous analyses of the problems and limitations of this approach, and how to overcome them, are still wanting. In this article, we...

Continuous nearest-neighbor search in the presence of obstacles
Yunjun Gao, Baihua Zheng, Gang Chen, Chun Chen, Qing Li
Article No.: 9
DOI: 10.1145/1966385.1966387

Despite the ubiquity of physical obstacles (e.g., buildings, hills, and blindages, etc.) in the real world, most of spatial queries ignore the obstacles. In this article, we study a novel form of continuous nearest-neighbor queries in the presence...

Design and analysis of a ranking approach to private location-based services
Man Lung Yiu, Christian S. Jensen, Jesper Møller, Hua Lu
Article No.: 10
DOI: 10.1145/1966385.1966388

Users of mobile services wish to retrieve nearby points of interest without disclosing their locations to the services. This article addresses the challenge of optimizing the query performance while satisfying given location privacy and query...

Reverse data exchange: Coping with nulls
Ronald Fagin, Phokion G. Kolaitis, Lucian Popa, Wang-Chiew Tan
Article No.: 11
DOI: 10.1145/1966385.1966389

An inverse of a schema mapping M is intended to undo what M does, thus providing a way to perform reverse data exchange. In recent years, three different formalizations of this concept have been introduced and studied, namely the...

Asymptotically efficient algorithms for skyline probabilities of uncertain data
Mikhail J. Atallah, Yinian Qi, Hao Yuan
Article No.: 12
DOI: 10.1145/1966385.1966390

Skyline computation is widely used in multicriteria decision making. As research in uncertain databases draws increasing attention, skyline queries with uncertain data have also been studied. Some earlier work focused on probabilistic skylines...

A relational approach to functional decomposition of logic circuits
Tony T. Lee, Tong Ye
Article No.: 13
DOI: 10.1145/1966385.1966391

Functional decomposition of Boolean functions has a profound influence on all quality aspects of cost-effectively implementing modern digital systems and data-mining. The relational databases are multivalued tables, which include any truth tables...

Closed world data exchange
André Hernich, Leonid Libkin, Nicole Schweikardt
Article No.: 14
DOI: 10.1145/1966385.1966392

Data exchange deals with translating data structured in some source format into data structured in some target format, given a specification of the relationship between the source and the target and possibly constraints on the target; and...