Hi Nidheesh,
I agree that this would be a great feature. My suggestion is that you create an Aha! idea and ask others to vote for it via the community. Doing so will definitely attract the attention of the product team.
If you had a custom UI, you would be able to do this filtering in your presentation layer. It may be possible to do something like this with a custom facet. I don't know, I haven't tried.
If you want to restrict yourself to out of the box capabilities, you may be able to put something together using the new conditional attribute functionality and having multiple lookups. The downside of this approach is the added maintenance and the fact that the lookup is stored across multiple attributes. The fact that Reltio only presents attributes that have values when performing a GET might make it useful in your use case.
If you decide to create the Aha!, I know I'd vote for it!
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Gino Fortunato
Senior Solution Engineer
Reltio
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