Looking for unused attributes

[Pawel]

I created two attribute sets: one global attribute set, serving as a catalog of objects, and another file attribute set where objects from the catalog are linked to individual photos. 

How can I look for objects from the global attribute set that are not referenced by any record in the file attribute set (like objects not linked to any photo)? 

[Mario]

That's quite an unusual task.

I understand that you reference global Attribute elements from your Attribute set.
So, if you have the global attributes A,B,C,D you want to find out which of these is not referenced by any of your per-file Attributes, right?

I doubt there is a direct way or shortcut for this.
You can filter for every global Attribute and if the result is empty, you have found one.

Or, maybe create a data-driven category which groups files based on the global Attribute. This should give you a list of all global Attributes used. By looking at the resulting categories, you can determine which of your global Attributes are not used.

Something alone that line. When I would ever need this, I would write a script or app to figure this out, probably.

[Pawel]

I understand that you reference global Attribute elements from your Attribute set.
So, if you have the global attributes A,B,C,D you want to find out which of these is not referenced by any of your per-file Attributes, right?

Exactly. Unfortunately, filtering objects manually is not an option, there are too many of them. 

I will probably try comparing exports of the file attribute set and the global set in Excel (after working on a file set in a pivot table or something), at least until I`ll grasp coding scripts and apps for IMatch.