4 constraint fk_person_id references person(person_id) on update CASCADE on delete RESTRICT,
6 constraint fk_person_id_2 references person(person_id) on update SET NULL on delete SET DEFAULT,
8 constraint fk_person_id_3 references person(person_id) on update NO ACTION,
11 constraint age_under_100 check ( age < 100 ),
12 constraint pk_pet primary key (pet_id, person_id)