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A transformation is a method by which you can apply and maintain a record of a design decision, which is a decision to change objects or properties within a design layer. When applied, a transform changes a set of objects from one state to another for the purpose of refining, normalizing, or denormalizing a model.
The creation process of the following transforms types will be reduced to the creation of the target objects of the transforms:
• Supertype-Subtype Roll Up
• Supertype-Subtype Roll Down
• Two Table Roll Up
• Two Table Roll Down
• Vertical Partitioning
• Horizontal Partitioning
The Many-To-Many (MTM) and the Supertype-Subtype (SS) relationships will be automatically transformed at the time of creation of the relationship object.
4. When ERwin will show the physical view the association table and its relationships will be shown and when ERwin will show the logical view the MTM relationship will be shown.
5. When the MTM relationship is deleted the association table and its relationships will be deleted as well. An advisory message will be displayed to inform the user about it. The ESXObjectSemantic_RelationshipDeleteNotification semantic will be used.
6. When the association table is deleted the MTM relationship will be deleted as well. An advisory message will be displayed to inform the user about it. The ESXObjectSemantic_EntityCreateDeleteNotification semantic will be used.
7. When any of the two association table relationships is deleted the MTM relationship will be deleted as well. An advisory message will be displayed to inform the user about it. The ESXObjectSemantic_RelationshipDeleteNotification semantic will be used.
5.2.1.3.2 Automatic Supertype-Subtype transformation
When an SS relationship is created via a supertype-subtype symbol between two entities ERwin will create a subtype relationship between those two entities. The relationship will have two layouts, one for logical view and one for physical view. The one for logical view will be a line linking the subtype symbol to the subtype entity and the one for physical view will be a line linking the supertype entity with the subtype entity. The following rules will apply:
1. To apply the transformation when an Supertype-Subtype relationship is created, the following semantic will be updated on the post edit event to create the second line that links the supertype entity with the subtype:
• ESXPropertySemantic_RelationshipCreate.cpp.
2. When ERwin shows the physical view, the subtype relationship line that links the supertype table and the subtype table will be shown.
This is all done by the drawing code. No transform specific code changes are required.
3. When the subtype symbol is deleted, the subtype relationships will be deleted as well. And when the last subtype relationship is deleted the subtype symbol will be deleted as well. From the transforms perspective no changes are required in order to support this functionality
Link Object:
The functionality previously implemented via the Column Denormalization transform will now be implemented via a completely new concept, the Link object.
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