Data mining is a powerful new technology with great potential to help companies focus on the most important information in the data they have collected about the behavior of their customers and potential customers. The material in this book formed the basis of undergraduate and Postgraduates courses at Anna University, University of Madras, Thiruvalluvar University, Bharathiar University, Bharathidasan University, Pondicherry University, and IT Professionals, and other south Indian universities. In 1993, the "father of data warehousing", Bill Inmon, gave this definition of a data warehouse: A data warehouse is a subject-oriented, integrated, time-variant, and nonvolatile collection of data in support of management's decision-making process.This book caters to the first or third-year course requirements of Computer Science, B.Sc., Software Computer Science, B.Sc. ISM, B.Sc. IT, B.Sc. Software System, B.Sc. Software Engineering, BCA, M.Sc. Computer Science, M.Sc. Information Technology, M.Sc. Information System and Management, M.Sc. Software Engineering, MCA, B.E.CSE, B.Tech. IT, M.E (CSE), M.Tech.(IT), M.Phil., of various south Indian universities.