Databases Reference
In-Depth Information
Business analyses
are often mentioned specifically during the interview
process. These include analyses that are currently performed on a regular
basis, samples of recent ad hoc analyses, and analyses that cannot be
completed in the current environment. Business themes can be identified
by looking at the underlying purpose of a business analysis. The goal of
identifying business analyses is not to compile a report inventory, but
rather to determine why a report is useful.
Business data
is mentioned in the interview to support reporting require-
ments and analyses. This is the type of data needed, not the specific file
or column name.
The broad business requirements, business analyses, and business data are
typically gathered at the same time through interviews. The interview content
is analyzed to net out each of these types of requirements. The next major
section of this chapter, ''Providing Business Requirements,'' explains these
three levels in great detail.
Before jumping into more detailed requirements gathering or design work,
it is important to take a moment to determine whether the results of the
requirements gathering process so far are aligned with the project charter and
scope. If not, this is the opportunity to set new priorities and then modify the
project charter and scope as necessary. Then, with confirmation of the origi-
nal project scope or a revised project scope, more detailed requirements can be
gathered. These are typically done in later stages of a data warehouse project,
but are included here to show a complete picture of all the requirements.
Specific reports, calculations, and screens
that will be part of the solution
must be defined to support the business analyses specified earlier. Defi-
nition of calculations begins during the data modeling process, which is
described in Chapter 7. Specific reports, analyses, and screens are defined
as part of the data delivery process detailed in Chapter 11.
Actual data sources
are now selected to be the source for the business data
that must be included, as defined by the business analyses. More detailed
analysis of the data content is also needed, as discussed in Chapter 8.
Business rules will need to be defined for the process that will extract,
transform, and load the data into the database. Chapter 10 provides more
details about developing the ETL process.
All of these requirements must be collected for the first data warehouse
project. The project charter and scope will help determine the group of people
needed to provide requirements input. The project scoping and prioritization
step will further narrow the focus for this project. Once the initial data
warehouse is built, then the process begins again. Subsequent projects do not
need to start over, but can confirm whether the broad business themes, business
analyses, and business data are still relevant. Any additional requirements can
