psql -f COPY from STDIN

The following command works fine when pasing it to psql via the -c
option:

cat event.csv | \
psql -c "COPY (event_id, event_name) FROM STDIN DELIMITER AS ',' NULL
AS ''"


When executed from a file via -f, it does nothing (no error messages
either):

event.sql:
COPY (event_id, event_name) FROM STDIN DELIMITER AS ',' NULL AS ''

cat event.csv | psql -f event.sql



What's the problem? Many thanks in advance.

-- 

Best Regards,
Tarlika Elisabeth Schmitz