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W H I T E P A P E R
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Front room BI applications
( ,pages 141-155). The front room is the public face of the DW/BI system.
[1]There's a broad range of of-the-shelf BI applications including ad hoc query and reporting BI tools,
dashboarding and scorecarding tools, andmore powerful analytic or mining/modeling applications.
The BI management services include a querying service (by far the most important), which is based on a
metadata service allowing to define a BI semantic layer simplifying and enhancing the presentation layer
structures for the business user's benefit. Additional services include access control and security, usage
monitoring, delivery of production-style predefined reports regularly to broad audiences, portal services and
web and desktop access. The data stores in this layer is comprised of stored reports, analytic application
caches, local user databases and/or spreadsheets, documents and presentations, authentication and
authorization data.
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Metadata:
Metadata is all the information that defines and describes the structures, operations, and contents of
these three DW/BI system components
( ,pages 170-173). It comes in three different types:
[1]—
Technical metadata
defines the objects and processes which comprise the DW/BI system. For
instance, source descriptions and job transformations from the backroom layer, database system tables
and table partition settings from the presentation layer, and BI semantic layer definition and query/report
definitions from the front room layer.
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Business metadata
describes the DW contents in user terms, including what data is available, where
did it come from, what does it mean, `and how does it relate to other data. For instance, business rule
definitions from the backroom layer, calculated measure definitions in the presentation layer, and
conformed attribute value lists from the front room layer.
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Processmetadata
describes the warehouse's operational results. For instance, quality results from the
backroom layer, aggregate usage statistics from the presentation server, and report and query usage
and execution from the front room layer.
4.3 Best Practices
This section lists some best practices from the reference book
,they appear in the sequel in
boldface
.
[1]4.3.1 Technical Architecture at Planning Stage
A DW/BI technical architect should
form and lead an Architecture Task Force
that includes someone with back
roomexperience, and front roomexperience, of ideally 2-4 persons.
During the gathering of business requirements, it is a good idea to
include in the interview plan questions
addressing architectural topics such as user counts, response time expectations, and analytic functionality.
To detail out a few architecture issues, it may be required to conduct follow-up interviews.
The DW/BI architect must
understand the existing/proposed technical environment
to identify elements that may
be leveraged, and any limitations or boundaries that the environment may impose.