ERwin Methods Guide |
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Information Systems, Databases, and Models
What’s In This Chapter?
Information systems can have numerous benefits to corporations, from automating tasks that were previously performed manually, to uncovering information and relationships that were previously unknown or undefined. In short, the benefits of information systems can be boiled down to a few key words: faster, better, and more.
However, to realize the benefits of information systems, you must be able to develop them in a timely and cost effective manner, so that they meet real business needs and are modifiable and maintainable with minimum expense. Achieving these goals is a major challenge -- a poorly designed system will end up costing more money and time than it saves.
The most important tool in reducing the cost of managing and retrieving information has become the relational database management system or RDBMS. An RDBMS provides a reliable and convenient means of storing, retrieving, and updating data.
Equally important is a method that reduces the cost of designing and managing relational databases. The most important and widely used method
is called data modeling. |
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Chapter Contents |
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What is Data Modeling?....................................................................................... |
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Data Modeling Sessions ....................................................................................... |
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Sample IDEF1X Modeling Methodology............................................................ |
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Logical Models...................................................................................................... |
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Physical Models .................................................................................................... |
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Benefits of Modeling in ERwin............................................................................ |
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Information Systems, Databases, and Models ∙ 9