SELECT party_name FROM party WHERE NOT party_id IN (SELECT party_id FROM member)
Show names of parties that does not have any members.
CREATE TABLE region (
    region_id number,
    region_name text,
    date text,
    label text,
    format text,
    catalogue text
)

CREATE TABLE party (
    party_id number,
    minister text,
    took_office text,
    left_office text,
    region_id number,
    party_name text
)

CREATE TABLE party_events (
    event_id number,
    event_name text,
    party_id number,
    member_in_charge_id number
)

CREATE TABLE member (
    member_id number,
    member_name text,
    party_id text,
    in_office text
)