In Oracle 19c, I have an MV which simply duplicates data from a remote table through a DB-link.
When doing a refresh of the MV with the method='c', the update takes forever (half an hour), but doing the update using method='?' (which is FORCE according to the docs) in seconds.
As far as I understood, due to lack if indices for the incremental update, MV refreshes via linked DB's only works in a complete way. So therefore, FORCE should fall back to 'c'.
I am obviously wrong somewhere or missing something. Can somebody explain this to me?