Refining a Model Using Transformations
A logical model and physical model represent design layers in the application development process. In each design layer, you can perform design activities that correspond to steps and decisions in the development process.
After you create a logical or physical model, you can automatically change model objects using a transformation. A transformation is a method by which you can apply a design layer decision. You can apply transformations to model objects using wizards to refine and optimize a design layer. For example, you can refine the physical model to improve query performance by applying a transformation to two tables and creating a single table.
You can use transformations to refine a model by:
- Rolling down two tables or entities and create a single table or entity
- Rolling up two tables or entities and create a single table or entity
- Resolving many-to-many relationships
- Rolling up subtype relationships
- Rolling down subtype relationships
- Creating an identifying relationship between a supertype entity and its subtype entities.
- Horizontally partition an entity or table
- Vertically partition an entity or table
Note: Both Many-to-Many relationship and Supertype-Subtype Identity transformations have the ability to display their source set of objects in the logical view and their target set of objects in the physical view. You can only apply these transformations in the logical model, or the logical side of a logical/physical model.
You can also synchronize properties between an existing source column and a new or existing target column by linking them using a Link object. The Link Wizard is used to create a Link object and to specify its properties and is launched from either the Attribute Editor or the Column Editor.
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