Creating a Data Model

You create a new data model by selecting File > New Model.

Note:

In addition to creating a data model from scratch with the following procedure, you can also:

• create a CDM by importing an ERwin model (.ERX) or by generating it from another PowerDesigner model.
• create an LDM by generating it from another PowerDesigner model.
• create a PDM by reverse-engineering it from an existing database (see Reverse Engineering a Database into a PDM) or generating it from another PowerDesigner model.

The New Model dialog is highly configurable, and your administrator may hide options that are not relevant for your work or provide templates or predefined models to guide you through model creation. When you open the dialog, one or more of the following buttons will be available on the left hand side:

• Categories - which provides a set of predefined models and diagrams sorted in a configurable category structure.
• Model types - which provides the classic list of PowerDesigner model types and diagrams.
• Template files - which provides a set of model templates sorted by model type.

1. Select File > New Model to open the New Model dialog.
2. Click a button, and then select a category or model type ( Conceptual Data Model, Logical Data Model or Physical Data Model ) in the left-hand pane.
3. Select an item in the right-hand pane. Depending on how your New Model dialog is configured, these items may be first diagrams or templates on which to base the creation of your model.
   Use the Views tool on the upper right hand side of the dialog to control the display of the items.
4. Enter a model name.
   The code of the model, which is used for script or code generation, is derived from this name using the model naming conventions.
5. [PDM only] Select a target DBMS , which customizes PowerDesigner's default modifying environment with target-specific properties, objects, and generation templates.
   

   By default, PowerDesigner creates a link in the model to the specified file. To copy the contents of the resource and save it in your model file, click the Embed Resource in Model button to the right of this field. Embedding a file in this way enables you to make changes specific to your model without affecting any other models that reference the shared resource.

6. [optional] Click the Select Extensions button and attach one or more extensions to your model.
7. Click OK to create and open the data model .
   Note: Sample data models are available in the Example Directory.

• Data Model Properties
  You open the model property sheet by right-clicking the model in the Browser and selecting Properties.
• Archiving a PDM
  Archived models store all constraint names without making a difference between user defined and calculated constraints. These models are used with the modify database feature.