1. create table alama (
codigo_a number(2)not null constraint ppk_codigo_a primary key,
nombre_a varchar2(25)
);
create table primaria(
codigo_p number(5) not null constraint ppk_cod_p primary key,
codigo_a number(5) constraint pfk_codigo_a references alama(codigo_a),
nombre_p varchar2(25)
);
insert into alama values(1,'wilmer');
commit;
insert into primaria values(99,1,'alama')
commit;