create table if not exists village
(
    id            serial       not null
        constraint village_pk
            primary key,
    name          varchar(256) not null,
    township_code varchar(256),
    longitude     double precision,
    latitude      double precision
);

comment on table village is '村';

comment on column village.township_code is '所属乡镇代码';

comment on column village.longitude is '经度';

comment on column village.latitude is '纬度';

create unique index if not exists village_id_uindex
    on village (id);




create table if not exists village_distance
(
    id             serial  not null
        constraint village_distance_pk
            primary key,
    origin_village integer not null
        constraint village_distance_village_id_fk
            references village,
    calc_village   integer
        constraint village_distance_village_id_fk_2
            references village,
    distance       integer
);

comment on table village_distance is '村之间的距离';

comment on column village_distance.origin_village is '原点村庄';

comment on column village_distance.calc_village is '相对计算村庄';

comment on column village_distance.distance is '距离 m';

create unique index if not exists village_distance_id_uindex
    on village_distance (id);