Administración especializada > Adecuación de los objetos de negocio > Administración de reglas de inicialización de objetos > Understanding Object Initialization Rules > Changing Versioning Schemes
  
Changing Versioning Schemes
Versioning schemes define the labels, or identifiers, that are automatically applied as object versions are created in a Windchill solution and define the order in which the labels are applied.
For all Windchill solutions, a rules load file sets the initial versioning rules for parts, documents, and CAD documents. These rules are in effect for all parts, documents, and CAD documents created from within any context. However, there is no out-of-the-box user interface for revising parts, documents, and CAD documents that are created within a project or program context (if Windchill ProjectLink is installed).
To use a versioning scheme other than one provided out-of-the-box, you can change a scheme that is defined for you or you can define your own scheme. You specify the versioning scheme in an object initialization rule for a particular object type, such as wt.doc.WTDocument. PTC recommends defining your own versioning scheme.
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If you make any changes to a versioning scheme, ensure that the revision labels are unique within each series in the versioning scheme. Specifying the same label multiple times in a series will lead to corrupt data. Also ensure that the versioning scheme that you want used is in place before allowing users to create documents, CAD documents, and parts. Changing the versioning scheme after objects are created can cause problems. If the scheme is changed in such a way that when revising an existing object, the current revision is not in the new versioning scheme, then an error occurs. For example, assume that an alphabetic scheme is in place when some objects are created and then the scheme is changed to an integer scheme. When the user tries to revise an object that is at version A, the operation fails because the new scheme does not have the alphabetic character A. For information on accommodating legacy revision labels, see Accommodating Legacy Characters in an Alphabetic Scheme and Accommodating Legacy Values in Revision Labels.
Object initialization rules can be set in context templates or by using the Object Initialization Rule Administration utility from within a specific context.
For a versioning rule, you must include the following:
MBA|versionInfo as the AttrValue id
com.ptc.core.foundation.vc.server.impl.VersionInfoGenerator as the algorithm
The version series name as the argument to the algorithm
For details on creating templates, see Creating Business XML Files for Context Templates.
The following sections describe the Harvard versioning schemes that are available and how to set them up for use within a context.