Data Management Capabilities > Managing Configurable Products > Windchill Options and Variants Capabilities > Working with Option Sets > Merging Option Sets
  
Merging Option Sets
To support nested configurable products, Windchill provides the Merge Option Sets action to merge the option sets of lower-level configurable products with the option set of top-level configurable product. While merging, the order defined in the lower-level option set is retained for the choices and options. Options from the lower-level option set are placed after options from the top-level option set.
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Ability to merge option sets is an advanced capability subject to a separate license entitlement.
For more information on configurable products, see Creating a Configurable Product.
Enabling the Merge Feature
Use one of the following methods to enable the feature:
Add the given property in the site.xconf file:
<Property name="ato.optionset.merge.delegate" targetFile="codebase/wt.properties" value="com.ptc.windchill.option.service.DefaultOptionSetMergeDelegate"/>
Add the given property in the xconfmanager utility to update the site.xconf file (Recommended method):
xconfmanager –s ato.optionset.merge.delegate=com.ptc.windchill.option.service.DefaultOptionSetMergeDelegate -t "codebase/wt.properties"
After adding the given property, ensure that you propagate the changes to the properties file using the xconfmanager utility. For more information on xconfmanager utility, see Using the xconfmanager Utility.
Restrictions and Limitations
Configurable products should use only one level of nesting.
Only local conditional rules should be defined for the option sets that are assigned to the lower-level configurable products.
Only advanced expressions should be assigned to parts, usages, and occurrences.