The 25th IEEE International Conference on Data Engineering (ICDE 2009) was held in Shanghai, China, on 29 March-2 April 2009. The conference call for papers attracted 545 submissions in the research track. The eight papers in this special issue were selected from the 93 long papers presented in Shanghai. Authors were invited to submit more complete and revised versions for this issue for a round of careful refereeing.
The paper titled "Projective Distribution of XQuery with Updates," by Ying Zhang, Nan Tang, and Peter Boncz examines the problem of partitioning XQuery queries and executing each subquery on the nodes where its relevant data resides, while respecting XML node identity and preserving structural properties. It presents a sequence of increasingly more refined semantics of parameter passing and associated techniques that lead to minimization of the semantic difference between local execution of the original query and remote execution of its set of partitioned subqueries.
XML is also the subject of the paper "Towards an Effective XML Keyword Search," by Zhifeng Bao, Jiaheng Lu, Tok Wang Ling, and Bo Chen. It deals with keyword-based search over XML data. By taking advantage of the structure of XML data, it establishes appropriate ways to detect users' intentions behind keyword searches, retrieve appropriate XML fragments, and rank the latter according to those intentions.
The paper "Continuous Subgraph Pattern Search over Certain and Uncertain Graph Streams," by Lei Chen and Changliang Wang, extracts simple features from graphs and checks for dominance relationships over the resulting feature vectors to identify given subgraph patterns in both certain and uncertain graph streams efficiently.
In "Adaptive Join Operators for Result Rate Optimization on Streaming Inputs," Mihaela A. Bornea, Vasilis Vassalos, Yannis Kotidis, and Antonios Deligiannakis propose two new adaptive join execution algorithms for maximizing the result production rate in two-way and multiway joins, respectively. They also present several experimental results where these algorithms outperform earlier approaches.
The paper "Maintaining Recursive Views of Regions and Connectivity in Networks," by Mengmeng Liu, Nicholas E. Taylor, Wenchao Zhou, Zachary G. Ives, and Boon Thau Loo, considers the maintenance of views over dynamic network state, represents state changes as streams of tuple updates, and addresses the problem efficiently by developing new techniques for compact representation of tuple derivability and data provenance and for minimizing communication in the network.
The paper "Histograms and Wavelets on Probabilistic Data," by Graham Cormode and Minos Garofalakis, addresses the problem of obtaining approximations of probabilistic databases based on histograms and wavelets. Being the first of its kind, it devises techniques that take into account the characteristics of the probability distribution of the data and have (near-)optimal results regarding the data approximation accuracy.
In the paper "Query Processing Using Distance Oracles for Spatial Networks," Jagan Sankaranarayanan and Hanan Samet provide space-efficient techniques that enable approximate calculation of the distance between two arbitrary nodes in a network.
Finally, the paper "BinRank: Scaling Dynamic Authority-Based Search Using Materialized SubGraphs," by Heasoo Hwang, Andrey Balmin, Berthold Reinwald, and Erik Nijkamp, deals with keyword search algorithms on top of large-scale database graphs. It partitions the graph into appropriate smaller subgraphs based on keyword cooccurrence in the database and then executes each query efficiently on only one of the subgraphs.
We believe that the papers in this special section reflect the diversity of problems that are being addressed currently by the database research community. A mix of rigorous investigations of novel domains and papers revisiting time-honored themes in a new light, they represent a cross-section of an exciting and rich field as it expands into new areas of data management. We would like to thank the authors of all of the papers for their efforts. Our deep appreciation also goes to the program committee members of ICDE 2009 and all those who participated in the additional reviewing phase that helped in improving the papers in this issue.
Y. Ioannidis is with the Department of Informatics and Telecommunications, University of Athens, Greece. E-mail: firstname.lastname@example.org.
D. Lee is with the Department of Computer Science and Engineering, Hong Kong University of Science and Technology, Hong Kong.
R. Ng is with the Department of Computer Science, University of British Columbia, Canada. E-mail: email@example.com.
For information on obtaining reprints of this article, please send e-mail to: firstname.lastname@example.org.
received the diploma degree in electrical engineering from the National Technical University of Athens in 1982, the MSc degree in applied mathematics from Harvard University in 1983, and the PhD degree in computer science from the University of California at Berkeley in 1986, and was on the faculty of the Computer Sciences Department of the University of Wisconsin at Madison, where he became a professor before leaving in 1999. He is currently a professor in the Department of Informatics and Telecommunications at the University of Athens, Greece. His research interests include database and information systems, electronic infrastructures, digital libraries, personalization, scientific systems, and human-computer interaction, topics on which he has published more than 100 articles in leading journals and conferences and holds three patents. Dr. Ioannidis is an ACM and IEEE fellow and has received the Presidential Young Investigator (PYI) award in 1991, the 2003 VLDB "10-Year Best Paper Award," the 2006 nation-wide "Xanthopoulos-Pnevmatikos Award for Outstanding Academic Teaching" in Greece, and several other teaching awards. He has been a program (co-)chair of ICDE '09 and several other conferences and a (co-)principal investigator in more than 30 research projects funded by various government agencies (Europe, Greece, USA) or private industry. Dr. Ioannidis currently serves a 4-year term as the ACM SIGMOD Chair (following a 4-year term as Vice-Chair) and is or has been a member of several other executive bodies of professional organizations (VLDB Endowment, IEEE TCDE Executive Committee, EDBT Endowment) and Scientific Advisory Boards (Max Planck Institute for Informatics, Greek National Science & Technology Council, Information Technology advisor to the Greek Minister of Health).
received the BSc degree in electronics from the Chinese University of Hong Kong, and the MS and PhD degrees in computer science from the University of Toronto, Canada. He is currently a professor in the Department of Computer Science and Engineering, Hong Kong University of Science and Technology. He was an associate professor in the Department of Computer Science and Engineering, Ohio State University, Columbus. He was the founding conference chair for the International Conference on Mobile Data Management, a PC cochair of ICDE 2009, a conference cochair for DASFAA 2011, and the chair of the ACM Hong Kong Chapter (1997). His research interests include information retrieval, search engines, mobile computing, and pervasive computing.
is a professor in computer science at the University of British Columbia, Canada. He is internationally renowned for his data mining studies. He has published more than 100 journal and conference papers covering a broad range of topics in informatics, data mining, and databases. He has won Best Paper awards from the ACM SIGKDD conference on data mining and the ACM SIGMOD conference on database management. For the past few years, Dr. Ng has been one of the editors of two top database journals worldwide—the VLDB Journal
and the IEEE Transactions on Knowledge and Data Engineering
. He was a general chair of ACM SIGMOD 2008 and a program chair of IEEE ICDE 2009.