Advanced Customization > Business Logic Customization > Customizing Change Management > Editing Attributes on the Links of Change Relationship Tables > Constraints and Limitations
  
Constraints and Limitations
The global attributes reference reusable attributes. In order to use other forms of attributes additional generation may be required. For general information see the “Managing Reusable Attributes” help topic for further details.
Two subtypes of the links (CustomAffectedActivityDataand, CustomChangeRecord2) are created to store the global attributes. This also shows the ease at which you can now use subtype links for the Affected/Resulting Objects tables for all change wizards.
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Change link Configuration Management only supports one link type per RoleA. If multiple are defined, only the most specific is used. The user cannot choose which link to use.
Two constraints are created with RoleA being the base class WTChangeActivity2 and RoleB being either the CustomAffectedActivityData or CustomChangeRecord2 links.
Only supported APIs are used in the examples
The code samples provide a good starting point for extending this customization to larger more complex scenarios (multiple attributes, embedded objects etc.)