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258 Part Two  Information Technology Infrastructure


                                   data in different ways using multiple dimensions. Each aspect of  information—
                                   product, pricing, cost, region, or time period—represents a different dimension.
                                   So, a product manager could use a multidimensional data analysis tool to learn
                                   how many washers were sold in the East in June, how that compares with the
                                   previous month and the previous June, and how it compares with the sales
                                     forecast. OLAP enables users to obtain online answers to ad hoc questions such
                                   as these in a fairly rapid amount of time, even when the data are stored in very
                                   large databases, such as sales figures for multiple years.
                                     Figure 6.13 shows a multidimensional model that could be created to  represent
                                   products, regions, actual sales, and projected sales. A matrix of actual sales can
                                   be stacked on top of a matrix of projected sales to form a cube with six faces.
                                   If you rotate the cube 90 degrees one way, the face showing will be product
                                   versus actual and projected sales. If you rotate the cube 90 degrees again, you
                                   will see region versus actual and projected sales. If you rotate 180 degrees from
                                   the  original view, you will see projected sales and product versus region. Cubes
                                   can be nested within cubes to build complex views of data. A company would use
                                   either a specialized multidimensional database or a tool that creates multidimen-
                                   sional views of data in relational databases.

                                   Data Mining
                                   Traditional database queries answer such questions as, “How many units
                                   of product number 403 were shipped in February 2013?” OLAP, or multidi-
                                   mensional analysis, supports much more complex requests for information,
                                   such as, “Compare sales of product 403 relative to plan by quarter and sales
                                   region for the past two years.” With OLAP and query-oriented data analysis,
                                   users need to have a good idea about the information for which they are
                                   looking.
                                     Data mining is more discovery-driven. Data mining provides insights into
                                   corporate data that cannot be obtained with OLAP by finding hidden patterns and
                                   relationships in large databases and inferring rules from them to predict future
                                   behavior. The patterns and rules are used to guide decision making and  forecast



                                         FIGURE 6.13  MULTIDIMENSIONAL DATA MODEL

























                                   This view shows product versus region. If you rotate the cube 90 degrees, the face that will
                                   show is product versus actual and projected sales. If you rotate the cube 90 degrees again, you will
                                   see region versus actual and projected sales. Other views are possible.








   MIS_13_Ch_06 Global.indd   258                                                                             1/17/2013   2:27:43 PM
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