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262                                                   10  Tool Support

            Fig. 10.1 Three dimensional
            OLAP cube containing sales
            data. Each cell refers to all
            sales of a particular product
            in a particular region and in a
            particular period. For each
            cell, the BI product can
            compute metrics such as the
            number of items sold or the
            total value







            (MicroStrategy), NovaView (Panorama Software), QlikView (QlikTech), SAS Enter-
            prise Business Intelligence (SAS), TIBCO Spotfire Analytics (TIBCO), Jaspersoft
            (Jaspersoft), and Pentaho BI Suite (Pentaho). The typical functionality provided by
            these products includes:
            • ETL (Extract, Transform, and Load). All products support the extraction of data
              from various sources. The extracted data is then transformed into a standard data
              format (typically a multidimensional table) and loaded into the BI system.
            • Ad-hoc querying. Users can explore the data in an ad-hoc manner (e.g., drilling
              down and “slicing and dicing”).
            • Reporting. All BI products allow for the definition of standard reports. Users
              without any knowledge of the underlying data structures can simply generate such
              predefined reports. A report may contain various tables, graphs, and scorecards.
            • Interactive dashboards. All BI products allow for the definition of dashboards
              consisting of tabular data and a variety of graphs. These dashboards are interac-
              tive, e.g., the user can change, refine, aggregate, and filter the current view using
              predefined controls.
            • Alert generation. It is possible to define events and conditions that need to trigger
              an alert, e.g., when sales drop below a predefined threshold an e-mail is sent to
              the sales manager.
            The BI tools mentioned before do not take an event log as a starting point. The input
            is relational data (i.e., one or more tables) or multidimensional data. The core of
            most BI tools is an OLAP (Online Analytical Processing) engine driven by tabular
            data organized in a so-called OLAP cube. Consider, for example, an OLAP cube
            containing sales data. As shown in Fig. 10.1, the dimensions of such a cube may
            include product type, region, and quarter. Assume we are interested in the number
            of items sold. In this case, the BI product can show the number of products sold
            for each cell in the OLAP cube. Suppose that in the fourth quarter (Q4) very few
            iPhones were sold in region West. Then one can drill down into this cell. For in-
            stance, one can look at individual sales, view the sales per month (refinement of Q4
            into October, November, and December), or view the sales per shop (refinement of
            the region dimension). When drilling down, the information is refined. Pivoting the
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