When doing a MERGE in Oracle SQL, how can I update rows that aren't matched in the SOURCE?

Question

I have a main database and a report database, and I need to sync a table from main into report.

However, when an item

Answer 1

merge into x as target using y as Source on target.ID = Source.ID
when not matched by target then insert
when matched then update
when not matched by source and target.ID is not null then
update whatevercolumn = 'isdeleted' ;