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In some
examples, a Travel Agency application is used for demonstration
purposes. The diagram shows the data model of this sample
application.
The data model shows:
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Keys (Primary, secondary, foreign) |
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Non-database columns (Virtual/Joined Columns or Additional
Fields) |
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Relationships (Parent-to-child) |
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Role names, e.g. GUIDES, FOR WHICH ARE MADE |
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Cardinality, e.g. 1-to-1 relationship or 1-to-many
relationship |
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Supertypes and subtypes |
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Exclusivity and totality for subtype groups |
Among other things, the
diagram does not show:
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Column characteristics such as Mandatory, Input Allowed |
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Co-role names, e.g. IS GUIDED BY, MADE FOR |
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Domains, domain characteristics |
Related Topics
Symbols in the Data Model
Relationships
Supertypes and Subtypes
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