Displaying the Serial Number of a Parent Item in Inventory Using a Relationship

You can create a relationship on the INVENTORY object to the ITEMSTRUCT object to use as a reference in Application Designer to display your data from the parent in Itemstruct in the Inventory application.

To create a relationship, launch Database Configuration:
Select the INVENTORY object
Select the Relationships tab
Select New Row
Give the relationship a name (remember this name) for this example we'll call it ITEMSTRUCTINV
Child Object: Itemstruct
Where Clause: (parent=:itemnum or parent is not null) and
itemsetid=:itemsetid and itemnum=:itemnum and itemid!=:itemnum
Save

Launch Application Designer and select Inventory application.
Select the Object Palette toolbar icon and drag and drop a textbox object where you want this new field.
Highlight the new textbox and select the Object Properties toolbar icon or right click on it and select properties.
In the Attribute property enter ITEMSTRUCTINV.SERIALNUM
The syntax is relationshipname.attributename where the relationship is the name from the previous step and the attribute name is the field from the child object.
In the Inputmode property field put the value READONLY so that user cannot change the original record's serialnum value through the relationship.
Save.