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Raghu Ramakrishnan's Home Page;;Raghu Ramakrishnan;Associate Professor of Computer Science;(raghu@cs.wisc.edu);Department of Computer Sciences;University of Wisconsin - Madison;1210 West Dayton Street,;Madison, WI 53706 USA;Phone: 608-262-9759 (Department: 262-1204, Fax: 262-9777); Education; Teaching Activities; Research Interests; Research Projects; Ph.D. Graduates; Education:; Ph.D. University of Texas at Austin, 1987.; B.Tech., Indian Institute of Technology, Madras, 1983.; Teaching Activities:; Course text:;Database Management Systems; Software for educational use:;Minibase;and; Coral;The text Database Management Systems, published by McGraw-Hill, is aimed;at first and second courses in database systems at the undergraduate;and graduate levels. The Minibase relational DBMS was developed in;conjunction with this text. The Coral system is also used in courses;that deal with logic databases at several schools.; Research Interests:; Integrating heterogeneous data sources; Content-based querying and indexing of sequence and image data; Exploratory analysis of large data sets (data mining); Extending database query languages using constraints and deduction;As the use of databases grows and diversifies, it is increasingly;important to be able to access data from dispersed, heterogeneous,;independently developed sources easily. In the RODIN project,;and its successor, the C.O.D. project, I am investigating several;issues: formal techniques and practical toolkits for;semantic integration, supporting multiple levels of service;and access to a database, and database access in a networked;cluster of machines. This is joint work with Profs. Ioannidis and Livny.;In recent work, the results on visual data exploration;from the; NEXT!;project, which is joint work with Prof. Livny,;are being applied to data integration, and querying over the Web.;My second area of interest is content-based querying of complex data such as;sequences and image sets. The; SEQ;system deals with;queries over sequence data, and focuses on DBMS design and optimization;issues related to sequence data. It is a part of the; NEXT!;project, and is joint work with Prof. Livny.;An important aspect of this work is its use for identifying;trends in the data, or in general, identifying useful patterns of;information.;In the PIQ project, the goal is to support content-based retrieval from;large sets of images. Our focus is on developing and implementing;an expressive data definition language that can be used to customize;a general image database system to take advantage of specialized;information about a given collection of images that is to be indexed;and queried.;My interest in querying and analysis of data covers data exploration and;mining. We have developed a powerful clustering algorithm called; BIRCH;for large datasets and a visual data exploration tool called; DEVise;as part of the; NEXT!;project.;A long-standing research interest is the extension of relational database;query languages with logic programming features;such as structured terms and recursion, and the use of;arithmetic constraints to specify data and queries more;compactly and efficiently.;An ongoing project involves the continued development and use of the CORAL;deductive system. The evaluation is based upon bottom-up fixpoint;evaluation techniques,;and several optimizations are applied to make it efficient;across a broad range of programs.; Research Projects:; CORAL; C.O.D.; NEXT!; PIQ; Ph.D. Graduates;S. Sudarshan,;Ph.D. August 1992,;Run-Time Optimizations in Bottom-Up Evaluation of Logic Programs,;First employment: AT&T Bell Labs, Murray Hill (sudarsha@research.att.com).;D. Srivastava,;Ph.D. August 1993,;Deductive and Object-Oriented Languages,;First employment: AT&T Bell Labs, Murray Hill (divesh@research.att.com).;S. Dar,;Ph.D. August 1993,;Design and Evaluation of Transitive Closure Algorithms,;First employment: AT&T Bell Labs, Murray Hill (dar@research.att.com).;P. Seshadri,;Ph.D. August 1996,;Sequence Data Management;First employment: Computer Sciences Department, Cornell University (praveen@cs.cornell.edu).;