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INTRODUCTION
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wishes to hold information. If the model succeeds, the things represented are
unlikely to change significantly, either with the application of new technology
(computer or other) or with the making of routine changes to the business of
the organization. Technology whose architecture is based on what is fundamen-
tal will improve the operational aspects of an organization while remaining
robust, stable, and flexible.
Unfortunately, what most people see in the course of their work (and conse-
quently tell systems analysts about) is not this unchanging nature at all, but
merely examples of it. They see only today's problems, and the particular tech-
nology they must use to do their jobs-to the point that the technology
becomes their job. Since the information an analyst gathers, therefore, is usually
expressed in terms of current practices, distinguishing between what is essen-
tial to a business and what is merely an accident of current technology is not
always easy. The essential facts are the things that "go without saying"-so
they don't get said. These facts don't get described or explained-or reflected
in new systems. Instead, new systems are often built on superficial views of
today's problems.
A plant that makes carbon black for printing ink and tires spent many
weeks discussing the best ways to determine production rates and yields. The
discussions concerned the best ways of predicting yield from the grade of nat-
ural gas that was used, but clearly something was not getting across. Finally,
the manager let slip the fact that yield is also a function of the production unit
used. The yield varies from unit to unit. This was obvious to him, so he didn't
mention it. Because it was not so obvious to the analyst, the original database
design had not taken this into account and had to be substantially redone.
The elements of a business that are typically portrayed in data models
reflect this difficulty. Instead of these essential facts about a business, model
diagrams are often dominated by references to the objects that represent the
particular way things are done now. A careless analyst may interpret transient
things to be things of importance. The resulting model will reflect only those
things that are important to wrrent business practices.
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A purchasing agent, for example, might describe the company's purchas-
ing system, giving special emphasis to its shortcomings (such as the fact that
there may not be enough room on a purchase order for notes), while neglecting
to describe the essential facts about a purchase order (such as the fact that
"terms of sale" must appear). To build a new system based solely on the struc-
ture (and failings) of an existing system is to fail to take advantage of techno-
logical opportunities. Suppose, for example, purchasing were to do away with
paper forms altogether and dial directly into vendors' computers. What would
remain essential to the transaction?
How Standards Can Help
Both communications and discipline can be improved. Moreover, we can make
better use of each other's work. What is needed is standardization of our