Server Administration > Item Fields > Creating Fields > Field Value Attribute Fields (FVA)
  
Field Value Attribute Fields (FVA)
If an item is related to another item through a single-valued relationship field or IBPL field, you can share information from the related item in an FVA field. For example, if Department items have a Manager field and a Phone Extension field, and Department items can be related to Defect items through a Manager IBPL field on the Defect, you can also create an FVA field on the Defect named Extension to Call that displays the phone number for the selected department manager. If you change the Phone Extension in the Department item, that change is reflected in the Defect item.
Note the following:
You cannot create an FVA field backed by a relationship field, a source link field, or a range field that is based on a numerical field value attribute field.
You cannot edit an existing FVA field and choose a different field type as the backing field. For example, if an FVA's backing field is the Summary short text field, you can choose a different short text field; however, an integer field is an invalid field type.
Users cannot edit an FVA field if it has no backing relationship.
If you create an FVA rich content field, it can only access attachments from an FVA attachment field over the same relationship as the FVA rich content field. This keeps the text and image data together. If the rich content field is not an FVA field, it should use non-FVA attachment fields. If you create a type with visible FVA and non-FVA rich content and attachment fields, Windchill RV&S only displays attachment fields visible to the user in the GUI or Web interface. From the CLI, the user must know which attachment fields to use with rich content fields.
If an FVA field is backed by a text field with parameter substitution, when you view the item through a view or report that supports parameter substitution, the substituted values from the item containing the backing field are displayed in the FVA field on the current item.
Field Value Attribute Fields: Values Tab
Field
Description
Relationship
The field containing the backing item for the FVA field. This field can be any of the following:
a relationship field (must be single-valued)
an item backed pick list field
the project field (if backing projects are enabled for the item type)
Field
The field in the backing item type that contains the value to display in the FVA field. The field must be visible in the backing item.
* 
Do not select a relationship field. Use of relationship fields for FVA fields is not supported.