We will bring together concepts from nearly all the previous chapters to build a data warehouse for a property and casualty insurance company in this final case study. If you are from the insurance industry and jumped directly to this chapter for a quick fix, please accept our apology, but this material depends heavily on ideas from the earlier chapters. You'll need to turn back to the beginning of the book to have this chapter make any sense.
As has been our standard procedure, this chapter is launched with background information for a business case. While the requirements unfold, we'll draft the data warehouse bus matrix, much like we would in a real-life requirements analysis effort. We'll then design a series of dimensional models by overlaying the core techniques learned thus far in a manner similar to the overlay of overhead transparencies.
Chapter 15 reviews the following concepts:
Requirements-driven approach to dimensional design
Data warehouse bus matrix
Complementary transaction, periodic snapshot, and accumulating snapshot schemas
Four-step design process for dimensional models
Handling of slowly changing dimension attributes
Minidimensions for dealing with large, more rapidly changing dimension attributes
Multivalued dimension attributes
Degenerate dimensions for operational control numbers
Audit dimensions to track data lineage
Heterogeneous products with attributes and facts that vary by line of business ...