Answer

Best Practice

• Copy the data in its original structure into another database.

Alternative

• Use a Postgres to SQL Server connector to copy the data to a secondary database.

Additional Information

• Keeping the data in the same structure will allow you to replace the data connection (if necessary). All fields are aligned automatically, because the new data connection has the same structure as the original one.
• Although Tableau Server does not archive any files, Tableau Support has seen cases in which users automatically back up their http_requests folder.