An introduction to data warehousing: what are the implications for the network?

T he need for analysing corporate data for I The user community of operational data is different from those using informational or trends and strategic information is hardly new. In an ideal world, the analyst could analytical data. I The processing characteristics for the opersimply query the operational database in a corporation to ascertain the long-term effects of ational environment and the informational environment are fundamentally different. a policy or the fiscal implications of a marketing decision. In reality, few operations environments I Data warehousing is an information systems environment, rather than a product. As an IS have the bandwidth—literally—to allow information seekers to create the elaborate queries environment, it is based on the organization’s information needs, competitive requirements necessary for sophisticated analysis of data. Hence, the development of data warehouses as an and investment criteria. Therefore, it is a subset of the corporate enterprise strategy, along essential—but separate—business entity has emerged. The split of operational and inforwith integrated business applications, on-line transaction processing, decision support mational databases occurred for several reasons: systems, and on-line analytical processing. I The data serving operational needs is physiI Data warehousing is concerned with inforcally different from that serving informational mational and analytic processing. Unlike or analytic needs. operational data which deals with the day-toI The supporting technology for operational day conduct of business, this information processing is fundamentally different from serves the needs of management in the that for informational or analytic needs. decision-making process. Often called DSS (decision support systems) or OLAP (on-line analytical processing), this analytical pro*Correspondence to: Dr Katherine Jones, 2 Alden Street, Newton cessing looks across broad vistas of data to Center, MA 02159, USA. Email: Katherine JonesKDGC.ceo.dg.com detect trends. Instead of looking at one or two