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Could They
Build the Sears Tower Without a
Blueprint?
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Why Data
Modeling Is Imperative
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By
Larry English
President, Information Impact
International, Inc. |
This article is
copyrighted by PLATINUM Technology, Inc., and was
originally published in the PLATINUM Edge:
Magazine. PLATINUM Technology, Inc., Volume 2,
Summer, 1995. All rights reserved.
Introduction
I started my
career in "data processing" at Sears in
1973 when the construction on the Sears Tower was
nearing completion. My signature is on the top
beam of the Tower, some 1454 feet above ground
level, in what is still the world's tallest
office building. The Tower has a fascinating
architectural plan that calls for nine
inter-linked sections or tubes to form a strong,
stable, yet flexible structure that allows its
110 floors to sway safely in the Windy City. The
Tower has reminded me of the requirement for data
modeling during the past 15 years of helping
organizations apply management principles to
information as a strategic business resource.
What if, I thought, the Sears Tower had been
architected like some organizations design their
databases? The thought is truly alarming.
Just as a complex
building requires a guiding architectural plan,
building a complex data infrastructure requires a
guiding data model. When performed properly, data
modeling is valuable and absolutely essential for
effective management of the enterprise's
information resources. It is required for both
effective shared databases with integrated
information systems, and for effective data
warehouses with comprehensive decision support
systems.
The case for data
modeling is a case for information management.
Information management is not possible without a
well-defined data model that accurately portrays
an enterprise's knowledge requirements and
controls database design.
What data modeling is
Data modeling is
not simply defining data for an application. It
is not developing a logical database design for
an application.
Data modeling is
the process of analyzing and representing the
"things" (entities) about which an
enterprise must know.1 A data model
represents the business facts (attributes) that
the enterprise must know about those business
entities, along with their relationships and
business rules. Data modeling requires business
personnel to wrestle with and achieve consensus
on the definition of data -- the business
vocabulary -- with the facilitation of a data
architect.
The data model as an
architecture
A data model is an
architectural blueprint that enables stable and
flexible database development. Stability means
new applications can reuse the database(s)
directly or by simply adding (but not modifying
existing) new entities, attributes and
relationships. Flexibility means the database(s)
can support changes to how the business
accomplishes its business processes without major
modification. A stable and flexible data model:
- Reduces the
costs of application development and
maintenance through reuse of commonly
defined data and reuse of the resulting
databases. A survey shows that of
organizations most effective in
implementing information resource
management principles, 75 percent have
reduced the costs of application
development and 83 percent have reduced
the costs of maintenance.2
- Reduces the
costs of interface programs that
transform data and move it from one place
to another by sharing data directly from
commonly defined databases.
- Reduces the
costs of managing the consistency of
unnecessary redundant data across
different applications by eliminating
multiple sources storing the same (or
similar) data.
- Reduces the
costs of correcting inconsistent data by
eliminating the need for multiple sources
of data and interface programs that can
be the source of error .
The data model as an
abstraction of business resources
A well-defined
data model enables cross-functional business
communication and represents the business
knowledge required to achieve the enterprise's
objectives. John Naisbitt states that in the new
economy of the Information Age, successful
companies must acknowledge that their primary
resource is information and their assets are
their employees.3 As a resource, data
shares business resources. For example, the
organization chart is a picture, or
"model" of how it has organized its
human resources. The chart of accounts is a
"model" of an organization's revenue
and expense categories. Organizations use these
models to understand, communicate, and manage
these resources. In the same way, a data model is
a tool to understand, communicate and manage the
organization's knowledge resource. Data is not
simply a resource -- it is a master resource.
Data is an abstraction that represents the
business resources and events, and the data model
represents the data. For example, customer John
Smith places order 12345 for item
"widget." The data model in figure 1
represents this business exchange.
Figure
1
A characteristic
of all resources is that it has a common life
cycle. As a resource itself, information has a
resource life cycle similar to that of financial
and human resources. Each resource has five major
processes: planning, acquisition, maintenance,
application, and disposition. Figure 2 represents
the resource life cycle for human resource
management.
Figure
2
Figure 3
represents the resource life cycle for
information resource management.
Figure
3
Four
of these processes are cost-adding. Only the
process of applying the resource adds value.
Resource management means maximizing resource
value in the processes that apply that resource
while reducing costs in the cost-adding
processes. The data model supports a data-driven
approach to application development. This update
approach minimizes unnecessary create and
processes (cost-adding) and maximizes the
retrieve processes (value-adding) by sharing the
data from commonly defined and accessed
databases.
As a
"picture" of the business resources, a
data model:
- Increases
communication among knowledge workers in
different business areas by have commonly
defined data.
- Increases
business opportunity by relating data
across functional areas and supporting
cross-functional queries.
- Increases
data quality by eliminating unnecessary
redundant data and sources of error.
- Enables
business process re-engineering by
eliminating non-value-adding processes
(redundant data entry and unnecessary
interface processes).
- Allows
effective management of the data resource
by having a model that represents the
enterprise data rather than going out to
all the business areas to know and manage
the data. (Consider managing inventory by
physical inspection of the stock versus
information representing the stock.)
Modeling
operational data versus data warehouse data
Both operational
databases and data warehouses require data models
for sound design. The data warehouse model has
distinct differences from its operational
counterpart:
| Operational Data Model: |
Data Warehouse Data
Model: |
| Data
supports operational processes |
Data
supports tactical and strategic processes
(decision support and executive
information support) |
| Fully
normalized for effective integrity
management |
De-normalized
for efficient retrieval |
|
| Current
data values (typically) |
Historical
data values |
| Minimal
derived data |
High
degree of summarized data |
| Contains
all operational data |
Contains
only data that has value over time |
If an organization
has not taken advantage of the benefits of data
modeling for its operational data, the data
warehouse represents a new opportunity to
"get it right the first time." Failure
to do so will spell disaster for the data
warehouse effort. The resulting data model with
consensus definition of key data can drive new
development and re-engineering of legacy
applications and databases.
How to make the case for
data modeling to management
The benefits of
data modeling are not automatic. Data modeling
requires cross-functional resources up front to
develop effective models and data-centric
applications that maximize data value. How does
one acquire and sustain management commitment?
- Start by
identifying key objectives of the
management whose support is required
- Describe in
business terms how the results of data
modeling enable accomplishing those
objectives
- Illustrate
the costs of not having a consensus data
model and shared databases:
- Conduct
an inventory of redundant files
for key data such as customer,
item or other critical
information
- Quantify
(estimate if there are no
accurate records) the cost of
developing and maintaining those
redundant files
- Quantify
(estimate if there are no
accurate records) the cost of
developing and maintaining the
unnecessary redundant
applications that create, update,
and interface the data
- Illustrate
the value of integrated databases to
exploit new business opportunity:
- Identify
business opportunities of
interest to management that are
not now achievable, or achievable
only with difficulty and with
excessive costs and/or
unacceptable time delays
- Document
the problems in the current data
structure and application design
that cause the excessive costs,
unacceptable delays or makes the
opportunity impossible to obtain
- Quantify
(with the help of business
personnel) the value of seizing
those business opportunities
- Document
how a well-defined data model and
data management enables seizing
those opportunities
Conclusion
So, just what
might the Sears Tower look like if it had been
constructed without an architectural blueprint?
It might look like a modern-day version of the
Winchester House, a Victorian mansion in San
Jose, California. Sarah Winchester, the widow of
the maker of the famed Winchester rifle,
perceived the spirits of those killed by her
husband's rifles were haunting her. Seeking
relief, she sought the aid of a spiritualistic
medium. The medium convinced her she could obtain
relief by moving west and continually building on
a house.
The Winchester
House is the result of constant construction, 24
hours a day, for 38 years without a master plan
or blueprint. Mrs. Winchester only made sketches
of individual rooms one at a time (like designing
databases for applications one at a time).
Because there was no rhyme or reason to the
construction, the 160-room house -- which started
with only 8 rooms -- has many anomalies. These
include staircases that lead to nowhere, windows
that open up to brick walls, and a chimney that
reaches within 6 inches of the ceiling, and a
door opening up to a two-story drop.
Will this be the
fate of some organizations' database
infrastructures? "Large organizations will
have little choice but to become
information-based," Peter Drucker asserts.4
The only way an organization can become
information-based is to have a sound foundation
of integrated data to support the business
processes and decisions of the enterprise. The
only way to have a sound foundation of integrated
data is with a stable and flexible data model.
ABOUT THE
AUTHOR
Larry P. English
is president and principal of Information Impact
International, Inc. He is an internationally
recognized speaker, teacher, consultant, and
author in information management.
He specializes in
analyzing trends for effective implementation of
information management. He is actively involved
in all aspects of information management,
including planning, organization, modeling and
methodology implementation. He has provided
consulting and educational services in at least
15 countries on four continents.
1 - Larry English,
Conceptual Data Modeling Student Guide. Oakbrook
Terrace, IL: Platinum Technology, 1994, pp.1-10.
2 - Larry English,
"The Information-Age Organization: A
Profile," fmi Journal, vol 3. no. 4. Winter
1993, p.3. The IRM survey was co-conducted by the
Database Research Group Inc. and Larry P.
English. Respondents included organizations from
North America and Europe that have an implemented
data management function.
3 - John Naisbitt,
and P. Aburdene, Re-inventing the Corporation,
New York, NY: Warner Books, 1985, p.5.
4 - Peter Drucker,
The New Realities., New York, NY: Harper &
Row, 1989, p.207.
Larry
English is featured at DCI's Data Warehouse World.
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