My first Publication Agile-Data-Warehouse-Design-eBook | Page 52

Modeling Business Events
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The 7Ws
BEAM ✲ uses the 7Ws: who, what, when, where, how many, why, and how to
discover and model data requirements as event details. Every event detail that
stakeholders need falls into one of the 7 W-types. They are the nouns for people
and organizations (who), things such as products and services (what), time (when),
locations (where), reasons (why), event methods (how), and numeric measures
(how many) that in combination form event stories. Event stories are
Each of the 7Ws is also an interrogative, a word or phrase that can be used to
construct a question, and that is precisely what you do with them. By asking
stakeholders a who question, you discover the people and organizations they want
to analyze. By asking stakeholders a what question you discover the products and
services they want to analyze. By asking these questions in the right combination
and sequence you discover the business events they need to analyze. Each of the 7Ws
told using the 7Ws
gives you a question
to ask for story
details
As you capture event details you can record their dimension type in the type row
of a BEAM✲ table. You will use this knowledge to help you model the details as
dimensions and facts. Part 2 of this book has chapters dedicated to the 7Ws,
covering common BI issues and dimensional modeling design patterns associ-
ated with each type.
Thinking Dimensionally
The 7W questions you ask to discover event details, mirror the questions that
stakeholders will ask themselves when they define queries and reports. For exam-
ple, a stakeholder will think about where, when, and how many to build a query
that asks: “Which sales locations are performing better than last year?” and who,
when, what, and why to ask: “Which customers are responding early to product
promotions?” When stakeholders start using the 7Ws they are thinking about their
data dimensionally, because the 7Ws represent how data is naturally modeled
dimensionally. Table 2-2 shows the type of data that each of the 7Ws represent
together with examples of matching physical dimensions or facts.
7W S
D ATA
The 7Ws help
stakeholders think
dimensionally about
their data and BI
queries
E XAMPLE D IMENSIONS ( AND F ACTS ) Table 2-2
7Ws data,
Who People and organizations Employee, Customer
What Things Product, Service
When Time Date/Calendar, Time of Day/Clock
Where Locations Store, Hospital, Delivery Address
Why Reasons and causality Promotion, Weather
How Transaction IDs and status
codes Order ID (Degenerate Dimension),
Call Status
How Many Measures and Key Perform-
ance Indicators (KPIs) Sales Revenue, Quantity (Facts)
dimensions
and facts