how do you retrieve the actual attachment document when rollup only displays the internal URL?

[K_M]

When I do a rollup to get the unique documents, it is correctly retrieving just the unique values - but while a lookup brings up the actual attachment documents, the rollup displays Airtable's Internal URL for the document.

How do I then retrieve the document? 

[TheTimeSavingCo]

Hmm I think you might need a combination of a script + a new attachment field in the rollup table to do this I'm afraid

[VikasVimal]

Depends on the use case. A lookup of the linked attachment field will pull the actual attachment from the linked record. You can use this in Airtable Interface or Base views.

If you want to see the attachment externally, I'd use Make.com to pass the recordID, then pull the attachments from the record and respond with a HTML showing the attachments or opening the attachment in a new tab.
This is a result of internal Airtable attachment urls not being accessible externally and any external links having a timeout of a few hours.