The Travel Agency Application

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Travel Agency Data Model

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:

· Tables

 

· Columns

 

· Keys (Primary, secondary, foreign)

 

· Non-database columns (Virtual/Joined Columns or Additional Fields)

 

· Relationships (Parent-to-child)

 

· Role names, e.g. GUIDES, FOR WHICH ARE MADE

 

· Cardinality, e.g. 1-to-1 relationship or 1-to-many relationship

 

· Supertypes and subtypes

 

· Exclusivity and totality for subtype groups

Among other things, the diagram does not show:

· Column characteristics such as Mandatory, Input Allowed

 

· Co-role names, e.g. IS GUIDED BY, MADE FOR

 

· Domains, domain characteristics

 

· Constraints

Related Topics:

Symbols in the Data Model

Relationships

Supertypes and Subtypes