OLAP - Narrative
Links to the essential reading, resources, activities, databases, advanced topic forum and assessment upload referred to in this narrative are in the theme block in myCourse.
Organisations have been attempting to analyse data to support decision making for many years. However, the often large amounts of internet “click stream” and operational data stored in databases, and a next generation of tools and methods, is leading to new and better opportunities for the analysis of business data. The term business intelligence is (currently) often used to describe this advance. This is an extensive subject area covering closely related topics such as data warehousing, dimension modelling, data mining etc. However, we are going to focus on dimension (or cube) modelling and the analysis of this multi-dimensional data (also refered to as OLAP) using the SQLDeveloper and Excel tools.
Smith - Decision Support Systems - Ch.16 is essential core reading for this theme, and provides a good overview. Note that decision support databases is perhaps a more generic and encompassing term that might be used to describe a data warehouse, OLAP cube, data mart etc or any other form of database that might be used to support decision making.
The core practical skills (and conceptual understanding) of this theme is based mainly on the "Analysing Multi-Dimensional Data" practice activity. The activity is based on a small OLAP "mySports" cube. We can see from this activity that SQL is less flexible for producing cross-tabular and other analyses. Excel, through its widespread use, is a popular alternative to OLAP tools such as Business Objects. Excel has limited analytical functionality, but this can be enhanced by add-ins now available.
The assessed activity involves implementing a decision support solution based on the larger, more realistic SH cube (with over a million records) and designing a dimension model based on the HR operational database,
Mondrian is an open-source OLAP tool, and is the advanced topic and forum for this theme.