Definitions and Concepts
A data warehouse (DW) is a pool of data produced to support decision making; it is also a repository of current and historical data of potential interest to managers throughout the organization.
Data are usually structured to be available in form ready for analytical processing activities (e.g., online analytical processing [OLAP], data mining, querying, reporting, other decision support applications).
A data warehouse is a subject-oriented, integrated, time-variant, nonvolatile collection of data in support of management’s decision-making process.