Chapter 3 DBMS Reference Guide
PowerDesigner can be used with many different DBMS resource files. For each of these DBMS, a standard definition file is included and provides an interface between PowerDesigner and the DBMS so as to establish the best relationships between them.
Different types of resource files are used to complement or further define standard PowerDesigner features. If you need more information about resource files, see chapter "The Resource Editor" in the General Features Guide .
Caution
You should never modify the DBMS files shipped with PowerDesigner. For each original DBMS you want to modify, you should create a corresponding new DBMS. To do so you have to create a new DBMS from the List of DBMS, define a name and select the original file in the Copy From dropdown listbox. This allows you to create a new DBMS that is identical to the original file apart from the name.
For more information on creating a new DBMS definition from an existing DBMS definition, see section "Creating a new definition file" in chapter "The Resource Editor" in the General Features Guide .
However, you may want to modify this interface to suit your particular applications. This is done with the DBMS definition file editor.
A DBMS definition file is a list of values and settings that represent specifications for a particular Database Management System (DBMS) in a format understandable by PowerDesigner. As an interface between an actual DBMS and PowerDesigner, it provides PowerDesigner with the syntax and guidelines for generating databases, triggers, and stored procedures appropriate for a target DBMS. The file itself is in .XML format.
The DBMS definition file is a required component of PowerDesigner when working with Physical Data Models (PDM). Each actual DBMS supported by PowerDesigner has its own DBMS definition.
All DBMS definition files have the same structure made up of a number of categories. A category can contain other categories, entries, and values. These entries are parameters recognizable by PowerDesigner.
The values for DBMS definition categories and entries vary for each DBMS. Some entries may not exist in the DBMS file if they are not applicable to the particular DBMS.
Certain entries contain mandatory parameters to generate correct syntax. Some entries contain SQL statements that will allow PowerDesigner to generate and reverse engineer correctly for the chosen database (create
, drop
, and so on).
You can incorporate variables in the SQL queries of the selected DBMS. These variables are replaced with the actual values from your model when the scripts are generated. These variables are evaluated to create corresponding objects in PowerDesigner models during reverse engineering.
PowerDesigner variables are written between percent signs (%).
CreateTable = create table %TABLE%
The evaluation of the variables depends on the parameters and the context. For example, the %COLUMN% variable cannot be used in a CreateTablespace parameter, because this variable is only known in a column parameter context.
For the full list of PowerDesigner variables that you can use in a DBMS Definition, see section "PDM variables".
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