create table regions (id int, name varchar(50))
create table refs(id int,ref_id int)
insert into regions (id,name) values (1,'СНГ')
insert into regions (id,name) values (2,'Белорусь')
insert into regions (id,name) values (3,'Россия')
insert into regions (id,name) values (4,'Минская область')
insert into regions (id,name) values (5,'Минск')
insert into regions (id,name) values (6,'Солигорск')
insert into regions (id,name) values (7,'Воронежская область')
insert into regions (id,name) values (8,'Воронеж')
insert into regions (id,name) values (9,'Лиски')

insert into refs(id,ref_id)values (1,1)
insert into refs(id,ref_id)values (2,2)
insert into refs(id,ref_id)values (3,3)
insert into refs(id,ref_id)values (4,4)
insert into refs(id,ref_id)values (5,5)
insert into refs(id,ref_id)values (6,6)
insert into refs(id,ref_id)values (7,7)
insert into refs(id,ref_id)values (8,8)
insert into refs(id,ref_id)values (9,9)
insert into refs(id,ref_id)values (2,1)
insert into refs(id,ref_id)values (3,1)
insert into refs(id,ref_id)values (4,2)
insert into refs(id,ref_id)values (4,1)
insert into refs(id,ref_id)values (5,4)
insert into refs(id,ref_id)values (5,2)
insert into refs(id,ref_id)values (5,1)
insert into refs(id,ref_id)values (6,4)
insert into refs(id,ref_id)values (6,2)
insert into refs(id,ref_id)values (6,1)
insert into refs(id,ref_id)values (7,3)
insert into refs(id,ref_id)values (7,1)
insert into refs(id,ref_id)values (8,7)
insert into refs(id,ref_id)values (8,3)
insert into refs(id,ref_id)values (8,1)
insert into refs(id,ref_id)values (9,7)
insert into refs(id,ref_id)values (9,3)
insert into refs(id,ref_id)values (9,1)
select refs.id
from refs join regions on refs.ref_id = regions.id and regions.name in ('СНГ','Россия')
group by refs.id 
having count(refs.id) = 2