create table rq (
id int primary key
);
create table ri (
id int primary key,
qid int not null,
constraint fk_ri_rq foreign key (qid) references rq(id)
);
create table rr (
id int primary key,
uid int not null,
iid int not null,
constraint fk_rr_ri foreign key (iid) references ri(id)
);
insert into rq values (1);
insert into ri values (1, 1), (2, 1), (3, 1), (4, 1), (5, 1);
insert into rr values (1, 1, 1), (2, 1, 2), (3, 1, 3), (4, 2, 4), (5, 2, 5);