Database Reference
In-Depth Information
building or using the application, there is a need to confirm and document our understand-
ing of their perspectives.
Take
Customer
for example. You can start off with the innocent question, “How do you
define
Customer
?” This question is not as easy to answer as it may appear because of the
many different perspectives on
Customer
. Once you get your answer, you can move on to
other data modeling questions, such as:
•
How do you identify a
Customer
?
•
How do you describe a
Customer
?
•
Can a
Customer
own more than one
Account
?
•
Can an
Account
be owned by more than one
Customer
?
•
Can a
Customer
exist without owning any
Accounts
?
These are some of the many questions that get asked during the data modeling process.
Asking and getting answers to questions like these is called
elicitation
, and data modeling
includes eliciting and documenting data requirements. There is an iterative process between
eliciting and documenting data requirements:
While data modeling, we ask questions to increase the precision of our data model, and
then through the process of documenting our data model, we ask more questions. This loop
continues until we are done with our model. A lot of knowledge is gained as the people in-
volved in the modeling process challenge each other about terminology, assumptions, rules,
and concepts.
