My first Publication Agile-Data-Warehouse-Design-eBook | Page 22

Introduction
XXIII
Cross-process analysis: Combining the results from multiple fact tables using
drill-across processing and multi-pass queries. Building derived fact tables and
consolidated data marts to simplify query processing.
Chapter 9: Why and How: Cause and Effect
Modeling causal factors: Using promotions, weather, and other causal dimensions
to explain why events occur and why facts vary. Using text dimensions to handle
unstructured reasons and exception descriptions.
Modeling event descriptions: Using how dimensions to collect any additional
descriptions of an event. Consolidating excessive degenerate dimensions as how
dimensions, and combining small why and how dimensions.
Multi-valued dimensions: Using bridge tables and weighting factors to handle fact
allocation (‘splitting the atom’) when dimensions have multiple values for each
atomic-level fact. Using optional bridge tables and multi-level dimensions to effi-
ciently handle barely multi-valued dimensions. Using pivoted dimensions to
support complex multi-valued constraints.
Providing additional how dimensions: Using step dimensions for understanding
sequential behavior, audit dimensions for tracking data quality/lineage, and range
band dimensions for treating facts as dimensions.
Appendix A: The Agile Manifesto
Appendix A lists the four values of, and the twelve principles behind, the manifesto
for agile software development.
Appendix B: BEAM✲ Table Notation and Short Codes
Appendix B summarizes the BEAM ✲ notation used throughout this book for
modeling data requirements, recording data profiling results and representing
physical dimensional modeling design decisions.
Appendix C: Resources for Agile Dimensional Modelers
Appendix C lists books, websites, and tools (hardware and software) that will help
you adopt and adapt the ideas contained in the book.
Companion Website
Visit modelstorming.com to download the BEAM ✲ Modelstormer spreadsheet
and other templates that accompany this book. On the site you will find example
models and code listings together with links to articles, books, and the worldwide
schedule of training courses and workshops on BEAM ✲ and agile data warehouse
design. Register your paperback copy online to receive a discounted eBook version.
Design patterns for
modeling cause and
effect