ORA-04020: deadlock detected while trying to lock object ...

[slimdave]

Do you understand what a deadlock is?


Also, not related to this subject, the trigger would be better as ...

CREATE OR REPLACE TRIGGER iprange_bifer BEFORE INSERT ON ip_range FOR EACH ROW
WHEN (new.id_iprange IS NULL)
BEGIN
SELECT iprange_seq.nextVal INTO :new.id_iprange FROM DUAL;
END;