Key features of PowerDesigner

• Transparency
  • Fast, facile graphics manipulation
    Create and move graphic objects with simple mouse movements. Select by mouse-click or rubber-band. Change color, line style, font, and alignment from the tool box, tool bar, right mouse menu, or main menu. Zoom with function keys, tool box icons, or menu options.

  • Intuitive object maintenance
    Double click any screen object for a self-explanatory dialog window which will lead you through all its available features and options.

  • Tight integration of Conceptual and Physical models
    Execute "Generate Physical Model" to immediately review the physical impact of conceptual designs. Make PDM changes (e.g., merge foreign keys, move columns, add indexes) and notice that the changes are preserved in the next PDM generation.

• Effectiveness
  • Enforced design methodology
    PowerDesigner enforces basic methodology where it is required for valid data modeling (e.g., uniqueness of object names, identity of entities, existence of some attributes in each entity). PowerDesigner offers advanced design techniques such as sub-typing inheritance, reuse of domains over multiple data items, and declarative check constraints.

  • Expert transformation from conceptual to physical
    The CDM "Generate Physical Model" dialog provides a list of target DBMS products which includes nearly every relational system actively used in the business world. The transformation of a conceptual model into a physical is governed by integral rules of relational logic (as in setting properties of table references). In addition PowerDesigner applies stored expert intelligence about the target database to translate conceptual definitions (e.g., data types) into physical ones (see "Open expert DBMS definitions" below).

  • Expert DDL generation
    Data Definition Language generated from an PowerDesigner physical model applies expert intelligence about the target DBMS (see "Open expert DBMS definitions" below). The resulting DDL is absolutely consistent with all modeled properties in the CDM and PDM (e.g., object names, data types, keys, indexes, foreign key constraints, check values), thus freeing DBAs from the tedium of manually reviewing DDL after each generation.

  • Template driven trigger code
    Create complete, reliable DBMS specific trigger code automatically from a powerful template programming language. Customize a trigger for one event (for example, to log deletions) and PowerDesigner will apply that custom logic to all tables referencing the custom trigger. Preview trigger output directly from any table or generate all triggers for a model. Where ever triggers are employed extensively, PowerDesigner's trigger generation will save many man-years of tedious, expensive, error-prone work.

  • Open expert DBMS definitions
    Expert DBMS intelligence is stored in open, ASCII text files (*.DEF) which the user can customize for site preferences. DDL for each DBMS target respects the appropriate rules of object maintenance to generate valid DDL and maintain referential integrity in the database.

  • Close 4GL links
    PowerDesigner can exchange all data design properties, including those specific to supported 4GLs, via the 4GL interface menu options.

• Abstraction
  • Automatic propagation of foreign keys
    Draw relationships at any time during entity definition - before or after entity identifiers are established. Change identifiers as needed during design and allow PowerDesigner to maintain the proper foreign key columns in the physical model.

  • Powerful sub-type inheritance
    Create data class hierarchies with multiple levels and multiple threads of inheritance. Model hierarchies conceptually freely and implement them in the physical model with any appropriate table structure.

  • Automatic resolution of many-to-many relationships
    Draw natural relationships (including reflexive or self-referencing) without inventing arbitrary associative entities because PowerDesigner will generate the required intermediate table in the physical model.

  • Unlimited sub-model graphics
    Visualize design objects in any number of sub-model contexts with immediate global synchronization.

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  Least understood aspects of PowerDesigner

  • Value of the Conceptual Model
    Since the paradigm of a "conceptual data model" linked to a "physical data model" is neither generally understood nor fully explained in PowerDesigner documentation, users do not immediately grasp the conceptualization and abstraction power of the CDM. They are often puzzled by the existence of two layers and regard the CDM as an annoying impediment.

  • Attributes vs. data items
    
    

  • Automatic foreign key migration
    
    

  • Dependency
    
    

  • Sub-typing
    
    or can generate
    
    

  • Sub-Models
    Users need to understand the power of unlimited concurrent sub-models. These enormously improve model clarity when dealing with more than 30-40 entities. Sub-models can be used for business functional grouping, entity related areas, temporary visualization, work-in-progress inventory, masking arbitrary entity sets in the global model, and many other purposes. There is no single use or purpose of a sub-model.

  • Domains
    Few users understand the importance and value of domains in fundamental relational theory. The controlled dynamic inheritance of data item / column properties is very powerful for centralized design.

  • Copy / Duplicate / Synonym / Copy to Sub-Model
    These four facilities appear similar and are frequently confused, with unanticipated consequences. Each has distinct and unrelated purposes and behaviors, all of which are useful in the appropriate circumstances.

  • Business Rules
    The current implementation of business rules is a "work in process". The interface does not yet make clear the object-oriented power inherent in capturing processing methods during data design.

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  Most frequent objections to PowerDesigner

  • Documentation is weak
    Users complain that both the on-line help and manuals are very sparse. They contain nothing which explains what to do or why to do it (i.e., design principles or methods), only how to do specific technical operations.

  • File formats are not published
    Users would like SDP to publish formats and general programming guides for INI, CDM, PDM, DEF, and CDF files plus documentation on the contents of the repository tables.

  • Some conceptual design features are inconveniently placed
    Several features which are strictly the concern of business analysts and conceptual designers are implemented in the Physical Data Model. These include naming PDM references, renaming columns generated from multiple relationships into the same conceptual entity, and all of the features on the PDM Referential Integrity window.

    Furthermore, several critical referential integrity properties (i.e., update and delete behavior, "change parent allowed") are only visible by descending two windows deep into an object dialog.

  • It is difficult to find objects in sub-models
    The "List of Entities" might offer a "Placement" button to discover in which sub-models an entity is placed. There needs to be a direct way to list which entities are not placed in any sub-model.

  • A PDM can only target one DBMS at a time
    Changing target databases in the PDM discards all user defined triggers. We need a reliable method to support multiple database targets from one conceptual design.

  • Enterprise version lacks adequate multi-user facilities
    Using the sub-model as the increment of control for team development is limited in large projects and teams.

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  Where to go from here:

  • AIS PowerDesigner Page
  • AIS CASE Page
  • AIS Home
  • Contact AIS at ddwelle@aisintl.com or feedback form

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