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An Introduction to the Data Warehouse -- Group D, IS 206, SIMS |
 | | Inmon, who is known as the "father of the data warehouse", defines the data warehouse as "a subject-oriented, integrated, time-variant, nonvolatile collection of data in support of management's decisions."(http://www.cait.wustl.edu/cait/papers/prism/vol1_no1/). |
 | | Further, all data in the data warehouse is "time variant", i.e., accurate as of some moment in time, whereas in the operational environment data is accurate as of the moment of access. |
 | | As data is loaded into the data warehouse from the operational environment or some external source, it is transformed and then goes into the current detail level, where it is used in the calculation of the lightly summarized data and the highly summarized data or in some ad hoc queries. |
| www.sims.berkeley.edu /courses/is206/f97/GroupD/datawarehouse.html (2196 words) |
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