Basic Administration > Administering Windchill > Contexts – Distributed and Hierarchical Administration > Context Administrative Items > Object Initialization Rules
  
Object Initialization Rules
Object initialization rule items consist of documents that contain XML elements that are formatted according to the object initialization rules DTD and are used in the following activities:
Initializing objects -- Rules can define specific default attribute values that are used when instances of objects of a specific type are created.
Constraining the display characteristics of attribute values -- Rules can set the following types of constraints on attributes:
Hidden -- the user interface does not display a value or label for the attribute.
Immutable -- The user cannot change the attribute value that is being displayed.
Server assigned -- The user interface does not display a value for the attribute; the value is generated and assigned when the instance of the object is saved.
Pregenerated -- The user interface displays a value for the attribute. The value is generated before the attribute is presented in the user interface.
Discrete set -- The user interface is constrained to picking from a discrete set of values.
Additionally, you can qualify when default values are set or when constraints are used for Windchill attributes by integrating the use of conditional logic algorithms in object initialization rules.
For details on the use of object initialization rules, see Object Initialization Rules.
Installed Site Object Initialization Rules
The object initialization rules established for each Windchill solution vary slightly, but include the following types of rule definitions:
Out-of-the-box numbering and versioning schemes for parts, documents, CAD documents, dynamic documents, and change objects. These schemes are simple Oracle sequences that have been loaded into the Windchill database. Each starts at 1 and increments by 1.
Default attribute values for folder paths, life cycles, and team templates for many object types.
Display constraints on attribute values such as numbering, life cycles, team templates, and organization identifier.
Conditional logic that allows for variations when setting constraints, numbering, versioning, and default attribute values.
For the complete set of object initialization rules established during the installation process, log in as the site administrator and navigate to Site > Utilities. Open the Object Initialization Rules Administrator to view the rules.
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The rules set in the site context work with the installed interface for each Windchill solution. PTC recommends that you do not modify the out-of-the-box object initialization rules that are set in the site context without understanding what the change affects.
Windchill PDMLink provides a demonstration template named Product Design that uses a different versioning scheme and two life cycle templates that you can use in evaluating what object initialization rules should be set for your site. For more information on the Product Design template, see Out-of-the-box Product and Library Context Templates.
For additional information about the out-of-the-box numbering and versioning schemes, see Administering the Numbering of Parts, Documents, CAD Documents, and Change Objects and Administering the Versioning of Parts, Documents, and CAD Documents.
For information about using the Object Initialization Rules Administration utility, see Object Initialization Rules.
Adding and Changing Object Initialization Rules
You can add and change object initialization rules by using the Object Initialization Rules Administration utility or by including the rules in a context template.
For more information, see Object Initialization Rules.