Hi Sandro,
I believe your requirement is similar to taking the last 4 digits of an ID like a SSN and putting it in a different attribute. Assuming I am correct, I think you have two choices with current capabilities 1) use the inbound process to parse the data and add the data to the new attribute (IMO, frequently the best option) or 2) use RIH or your favorite integration tool to listen to the Reltio queue and parse the Id and populate the data after the fact.
HTH
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Gino Fortunato
Senior Solution Engineer
Reltio
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