ERwin Methods Guide |
3 |
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The Key-Based Model
What’s In This Chapter?
A Key-Based Model (KB) is data model that fully describes all of the major data structures that support a wide business area. The goal of a key-based model is to include all entities and attributes that are of interest to the business.
As their name suggests, key-based models also include keys, which are the elements of the data model that are used to identify unique instances within an entity and, when implemented in a physical model, provide easy access to the underlying data.
Basically, the key-based model covers the same scope as the ERD, but exposes more of the detail, including the context in which detailed implementation level models can be constructed.
Chapter Contents |
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Understanding Keys............................................................................................. |
28 |
Relationships and Foreign Key Attributes.......................................................... |
32 |
Rolenames ............................................................................................................. |
36 |
The Key-Based Model ∙ 27