Chapter 4 Building Multidimensional Diagrams
A multidimensional diagram is a model of business activities in terms of cubes and dimensions. It organizes business data into one or other of these categories. Numeric values or measures such as sales total, budget limits, are the facts of the business. The area covered by a business, in terms of geography, time, or products are the dimensions of the business.
The multidimensional diagram is used to design an OLAP database. Information in an OLAP database is organized to facilitate the queries performed by different tools.
OLAP databases are populated with data from a data warehouse or data mart database. This data transfer is implemented via a relational to multidimensional mapping, the data warehouse or data mart database being the data source of the OLAP database. The OLAP cube is designed to support multidimensional analysis queries, it is organized according to user-defined dimensions.
For more information on the relational to multidimensional mapping, see the "Defining a relational to relational mapping" section in the Working with PDMs chapter.
Sales data can have the dimensions product, region, customer, and store. Facts, for example, the sales totals, are viewed through the user-defined dimensions. When you retrieve the sales total of a particular product for a particular region, you are viewing the sales total through the product and region dimensions. The most common dimension is time because the purpose of multidimensional analytical queries is to find trends.
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