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In a logical/physical model, each model that you create automatically includes both a logical and a physical model. By default, the logical model is closely related to the physical model.
You can use either the logical model or the physical model to define and document database structures, although the model you use typically depends on the type of work you want to perform. You can use the logical model to represent business information and define business rules in a fully normalized model, while the physical model supports the needs of the database administrator, who focuses on the physical implementation of the model in a database.
The differences between the logical model and the physical model are seen in the features and options available in the user interface, and the different editors you can use
The differences between the logical model and the physical model can also be seen in the features and options available in the user interface and the editors, including:
Although previous versions of this product also supported both logical and physical constructs, you can now create a logical model that is different from, but related to, a physical model. For example, you can flag certain objects in the logical model as logical only so that they do not appear in a corresponding physical model. Conversely, you can flag certain objects in the physical model as physical only so that they do not appear in a corresponding logical model. This is accomplished in the property editor for that object.
Other items are available for one modeling environment but not the other. For example, you can create many-to-many relationships and subtype relationships in the logical model only (however, they can be viewed in the physical model). You then resolve these constructs in the physical model. Similarly, you can include views and view relationships in the physical model only.
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