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This revised and expanded edition of Encyclopedia of Database Systems provides easy access to crucial concepts relevant to all aspects of very large databases, data management, and database systems, including areas of current interest and research results of historical significance. This comprehensive reference is organized alphabetically and each entry presents basic terminology, concepts, methods and algorithms, key results to date, references to the literature, and cross-references to other entries. Topics for the encyclopedia-including areas of current interest as well as research results of historical significance-were selected by a distinguished international advisory board and written by world-class experts in the field. New entries that reflect recent developments and technological advances in very large databases include: big data, big data technology, cloud computing, cloud data centers, business analytics, social networks, ranking, trust management, query over encrypted data, and more. Entirely new entries include database systems, relational database systems, databases, multimedia databases, bioinformatics, workflow systems, and web data management.

Encyclopedia of Database Systems, 2nd edition, is designed to meet the needs of researchers, professors, graduate and undergraduate students in computer science and engineering. Industry professionals, from database specialists to software developers, will also benefit from this valuable reference work.

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M. Tamer Özsu is Professor of Computer Science at the David R. Cheriton School of Computer Science of the University of Waterloo. He was the Director of the Cheriton School of Computer Science from January 2007 to June 2010. Previously he was with the Department of Computing Science of the University of Alberta (1984 - 2000). His PhD is from the Ohio State University. His research is in data management focusing on large-scale data distribution and management of non-traditional data. His publications include the book Principles of Distributed Database Systems (with Patrick Valduriez), which is now in its third edition. He has also edited, with Ling Liu, the Encyclopedia of Database Systems. He serves as the Series Editor of Synthesis Lectures on Data Management (Morgan & Claypool) and on the editorial boards of three journals, and two book Series. He has served as the Program Chair and General Chair of a number of international conferences. He is a Fellow of the Association for Computing Machinery (ACM), and of the Institute of Electrical and Electronics Engineers (IEEE), and a member of Sigma Xi. He has held a University Research Chair (2004-2011) and a Faculty Research Fellowship (2000 - 2003) at the University of Waterloo, and a McCalla Research Professorship (1993-1994) at the University of Alberta. He was awarded the ACM SIGMOD Contributions Award in 2006, and The Ohio State University College of Engineering Distinguished Alumnus Award in 2008. Dr. Özsu serves on the Scientific Advisory Board of National Institute of Informatics (NII) of Japan and the Advisory Board of School of Engineering of Hong Kong University of Science and Technology. He is the Vice Chair for new publications of ACM Publications Board. Ling Liu is a Professor in the School of Computer Science at Georgia Institute of Technology. Ling´s research interests are in the areas of database systems, distributed computing, and Internet data management and data mining with the focus on performance, availability, fault tolerance, security and privacy. Ling has published over 300 International journal and conference papers and supervised more than 20 Ph.D. dissertations. She is a recipient for 2012 IEEE CS Technical Achievement Award and a recipient of 2012 Outstanding Doctoral Thesis Advisor award from Georgia Institute of Technology. She has received numerous best paper awards from venues such as IEEE International Conference on Distributed Computing Systems (2003), International Conference on World Wide Web (2004), IEEE International Conference on Cloud Computing (2012), and 2005 Pat Goldberg Memorial Best Paper Award. Ling is currently the Editor in Chief of IEEE Transactions on Service Computing (TSC), and on the editorial board of several international journals, including Journal of Parallel and Distributed Computing (JPDC), ACM Transactions on Web (TWEB), ACM Transactions on Internet Technology (TOIT), and Distributed and Parallel Databases (Springer).

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