existing.sql

create table male
  ( male_id  int           not null
  , primary key (male_id) );

create table female
  ( female_id  int           not null
  , primary key (female_id) );

create table name
  ( id   int        not null
  , name text       not null
  , primary key (id));



create view gender as
  select 'm' as gender, male_id as id from male
  union
  select 'f' as gender, female_id as id from female;


create view person as
  select n.id, n.name, g.gender
  from name n join gender g on n.id = g.id;
  
  
insert into name values (1, 'John');
insert into male values (1);
insert into name values (2, 'Jane');
insert into female values(2);

select * from person;
  
update name set name = @new_name where id = @person_id