A junior data engineer has written the following SQL code:

MERGE INTO events
USING new_events
ON events.event_id = new_events.event_id
WHEN NOT MATCHED THEN
INSERT *

The view new_events contains records with the same schema as the Delta table events, where event_id is the unique key.

What will occur when this query runs for new records that have an event_id matching an existing record in the events table?