create table creators
(
    creator_id  integer primary key not null default nextval ('creators_seq'),
    name        text            not null,
    last_name   text            not null,
    birth_date  date,
    nationality text
);

create table participants
(
    movie_id   integer not null,
    role_id    integer not null,
    creator_id integer not null,
    PRIMARY KEY (movie_id, role_id, creator_id),
    foreign key (movie_id) references movies (movie_id),
    foreign key (role_id) references roles (role_id),
    foreign key (creator_id) references creators (creator_id)
);

ALTER TABLE participants ADD CONSTRAINT jakiś_name FOREIGN KEY(creator_id) references creators (creator_id);