1-1 grails relationship: child+parent

1-1 grails relationship: child+parent

/**
Target
	Promocion

Promocion
	Target
**/

create table target (
	id bigint generated by default as identity, 
	version bigint not null, 
	descripcion varchar(255), 
	nombre varchar(255) not null, 
	promocion_id bigint, primary key (id));

create table promocion (
	id bigint generated by default as identity, 
	version bigint not null, 
	nombre varchar(255) not null, 
	target_id bigint, primary key (id));