with q(id, val) as (select 1 ,'Значение_1(1)' from dual union all
select 1 ,'Значение_2(1)' from dual union all
select 1 ,'Значение_3(1)' from dual union all
select 2 ,'Значение_1(2)' from dual union all
select 2 ,'Значение_2(2)' from dual union all
select 2 ,'Значение_3(2)' from dual union all
select 3 ,'Значение_1(3)' from dual union all
select 3 ,'Значение_2(3)' from dual union all
select 3 ,'Значение_3(3)' from dual)

, w as (select id, val, dense_rank() OVER(partition by id order by id, val) as rn from q)
, e as (select id, val, dense_rank() OVER(partition by rn order by id, val) as rn2, rn from w)

select ltrim(SYS_CONNECT_BY_PATH(val, ' ')) as Path
 from e
where CONNECT_BY_ISLEAF = 1
start with rn2 = 1
connect by prior rn = rn
and level = rn2
and prior dbms_random.value is not null