Foreign key constraints allow inconsistent state?

[jean-lopes]

Hi, I'm fiddling around with the project and this behavior seems odd to me, can anyone confirm it is the expected outcome?

CREATE TABLE uk (id integer, s integer, e integer, CONSTRAINT uk_pkey PRIMARY KEY (id, s, e));
SELECT periods.add_period('uk', 'p', 's', 'e');
SELECT periods.add_unique_key('uk', ARRAY['id'], 'p', key_name => 'uk_id_p', unique_constraint => 'uk_pkey');

CREATE TABLE fk (id integer, uk_id integer, s integer, e integer, PRIMARY KEY (id));
SELECT periods.add_period('fk', 'q', 's', 'e');
SELECT periods.add_foreign_key('fk', ARRAY['uk_id'], 'q', 'uk_id_p', key_name => 'fk_uk_id_q');

INSERT INTO uk(id, s, e)
    VALUES (1, 1, 3)
         , (1, 3, 5);

INSERT INTO fk(uk_id, id, s, e)
    VALUES (1, 1, 1, 2)
         , (1, 2, 2, 5);

--expected: fail,    behavior: deleted
delete from uk where (id, s, e) = (1, 1 ,3);

--expected: fail,    behavior: failed
delete from uk where (id, s, e) = (1, 3 ,5);

INSERT INTO uk(id, s, e)
    VALUES (2, 1, 5);

INSERT INTO fk(uk_id, id, s, e)
    VALUES (2, 4, 2, 4);

--expected: fail,    behavior: updated
update uk set e = 3 where (id,s,e) = (2,1,5);