Database Reference
In-Depth Information
Document Collection
Every information system has existing paper forms, online forms, reports, manuals, written procedures, and
other documents that contain valuable system requirements. You should review all these documents and then
confirm their validity with end users. Documents are a rich source for the data content of an information
system, and are a quicker, more accurate way of determining the data, database, and information
requirements than asking end users, although you need to verify the documents
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accuracy with end users.
Observation
Observing current operating processing provides insight into how users interact with the system and how the
interaction can be improved. Observation verifies what you learn during interviews and what is documented
in procedure manuals. Observation can also identify undocumented processing and uncover processing that
differs from standard practice.
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Research
Few information systems are unique in their total system requirements. You can research journals,
periodicals, books, and the Internet to obtain information, examples, and requirements related to a specific
information system. You can also attend professional seminars and visit other companies to gain insight
from other experts.
TRANSITIONING FROM SYSTEMS ANALYSIS TO SYSTEMS DESIGN
After you
ve determined all the system requirements for an information system, you need to analyze and
document the requirements. The Unified Modeling Language, briefly discussed in Chapter 9, is one approach
you can use to model (analyze and document) system requirements; this approach uses class, use case, state,
and other diagrams and modeling tools to model an information system. Another popular approach uses data
flow diagrams to model the transformations of data into information, a data dictionary for data and table
documentation, and various process description tools and techniques. System developers have additional
approaches available to model system requirements. When you
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ve completed
the systems analysis work, which consists of both the requirements determination step and the analysis and
documentation step.
The approach you choose to transition from systems analysis to systems design will result in a large,
complicated model of the information system. You use this model to perform the system design of the
information system next. To simplify the design process, you can attack the design in smaller pieces by
considering individual user views, as described in Chapter 6.
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ve completed the model, you
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