Chapter 2 Resource Files and the Public Metamodel

The PowerDesigner Public Metamodel

A metamodel describes the elements of a model, and the syntax and semantics of their manipulation. Where a model is an abstraction of data, and can be described using metadata, the metamodel is an abstraction of that metadata.

The PowerDesigner public metamodel is an abstraction of the metadata for all the PowerDesigner models, which is represented in an object-oriented model. It is intended to help you understand the overall structure of the PowerDesigner modeling metadata when working with:

• VB scripts
• Generation Template Language (GTL) templates
• PowerDesigner XML model files (see The PowerDesigner XML Model File Format)

The public metamodel OOM is documented in the Visual Basic help file (click Help→Metamodel Objects Help) and is located at:

[PowerDesigner install dir]\Examples\MetaModel.oom

The metamodel is divided into the following main packages:

• PdBPM - Business Process Model
• PdCDM - Conceptual Data Model
• PdCommon - contains all objects shared between two or more models, and the abstract classes of the model. For example, business rules, which are available in all models, and the BaseObject class, from which all model objects are derived, are defined in this package. Other model packages are linked to PdCommon by generalization links indicating that each model inherits common objects from the PdCommon package.
• PdFRM - Free Model
• PdILM - Information Liquidity Model
• PdMTM - Merise Model (available in French only)
• PdOOM - Object Oriented Model
• PdPDM - Physical Data Model
• PdRMG - Repository
• PdRQM - Requirements Model
• PdXSM - XML Model
• PdWSP – Workspace

Each of these top-level packages contains the follow kinds of sub-objects, organized by diagram or, in the case of PdCommon, by sub-packages:

• Features - All the features implemented by classes in the model. For example, Report (available in all models) belongs to PdCommon, and AbstractDataType belongs to PdPDM.
• Objects - Design objects in the model
• Symbols - Graphical representation of design objects

Copyright (C) 2008. Sybase Inc. All rights reserved.