Remove duplicate in string and/or concatenate words

[Brian_Boyd]

See the attached screenshot for an idea of what I’m trying to accomplish. I’m using a formula to concatenate the names of sellers and buyers. Simple except that if there are two or more names, how can I remove the identical last name, or add an & between names if they are different names?

[Justin_Barrett · Accepted solution]

This can be done using a single rollup field. Roll up the last name based on the {Linked to Contacts}, and use this aggregation formula:

IF(values, "Seller to " & ARRAYJOIN(ARRAYUNIQUE(values), " & "))

The ARRAYUNIQUE() function gets rid of duplicate last names, ARRAYJOIN() joins them with the ampersand, and the rest adds the prefix as long as there’s one incoming name.

[Brian_Boyd]

Thank you so very much. This works perfectly.