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ERwin Methods Guide

4

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Naming and Defining Entities and Attributes

What’s In This Chapter?

It is extremely important in data modeling, and in systems development in general, to choose clear and well thought out names for objects. The result of your efforts will be a clear, concise, and unambiguous model of a business area.

Naming standards and conventions are identical for all types of logical

 

models, including both the entity-relationship diagrams and key-based

 

diagrams discussed in previous chapters.

 

Chapter Contents

 

Naming Entities and Attributes ..........................................................................

37

Entity Definitions..................................................................................................

40

Attribute Definitions ............................................................................................

43

Rolenames .............................................................................................................

44

Definitions and Business Rules............................................................................

46

Naming and Defining Entities and Attributes 37

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