Datawarehousing For Dummies

What’s in a Data Warehouse?
In This Chapter
▶ Understanding what a data warehouse is and what it does
▶ Looking at the history of data warehousing
▶ Differentiating between bigger and better
▶Grasping the historical perspective of a data warehouse
▶ Ensuring that your data warehouse isn’t a data dump
I
f you gather 100 computer consultants experienced in data warehousing
in a room andgive them this single-question written quiz, “Define a
data warehouse in 20 words or fewer,” at least 95 of the consultants will turn
in their paper with a one- or two-sentence definition thatincludes the terms
subject-oriented, time-variant, and read-only. The other five consultants’
replies will likely focus more on business than on technology and use a
phrase such as “improve corporatedecision-making through more timely
access to information.”
Forget all that. The following section gives you a no-nonsense definition
guaranteed to be free of both technical and business-schooljargon.
Throughout the rest of the chapter, I assist you in better understanding
data warehousing from its history and overall value to your business.
The Data Warehouse: A Place
for Your Data Assets
Adata warehouse is a home for your high-value data, or data assets, that
originates in other corporate applications, such as the one your company
uses to fill customer orders for its products, orsome data source external
to your company, such as a public database that contains sales information
gathered from all your competitors.
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Part I: The Data Warehouse: Home for Your Data Assets
Ifyour company’s data warehouse were advertised as a product for sale, it
might be described this way: “Contains high-quality, refined and purified
information, all of which has undergone a 25-pointquality check and is
offered to you with a warranty to guarantee hassle-free ownership so that
you can better monitor the performance of your business.”
Classifying data: What is a data asset?...