Ниже для BigQuery Standard SQL
#standardSQL
SELECT * EXCEPT(ids),
(SELECT id FROM UNNEST(ids) id GROUP BY id ORDER BY COUNT(1) DESC LIMIT 1) New_Family_id
FROM (
SELECT *, ARRAY_AGG(FamilyId) OVER(PARTITION BY ProductTitleNL) ids
FROM `project.dataset.table`
)
Вы можете тестировать, играть с выше, используя фиктивные данные из вашего вопроса, как показано ниже
#standardSQL
WITH `project.dataset.table` AS (
SELECT 9200000005045711 GlobalId, '! at Gun Point...' ProductTitleNL, 9200000005045710 FamilyId UNION ALL
SELECT 9200000003809684, '! at Gun Point...', 9200000011427871 UNION ALL
SELECT 9200000011427872, '! at Gun Point...', 9200000011427871 UNION ALL
SELECT 1001004011099420, 'Russian Dat', 34388968 UNION ALL
SELECT 1001004011099421, 'Russian Dat', 35434738 UNION ALL
SELECT 9200000000530359, '!!Nos Vemos!', 9200000000530358 UNION ALL
SELECT 9200000000530343, '!!Nos Vemos!', 9200000000530342
)
SELECT * EXCEPT(ids),
(SELECT id FROM UNNEST(ids) id GROUP BY id ORDER BY COUNT(1) DESC LIMIT 1) New_Family_id
FROM (
SELECT *, ARRAY_AGG(FamilyId) OVER(PARTITION BY ProductTitleNL) ids
FROM `project.dataset.table`
)
с результатом
Row GlobalId ProductTitleNL FamilyId New_Family_id
1 9200000005045711 ! at Gun Point... 9200000005045710 9200000011427871
2 9200000003809684 ! at Gun Point... 9200000011427871 9200000011427871
3 9200000011427872 ! at Gun Point... 9200000011427871 9200000011427871
4 9200000000530359 !!Nos Vemos! 9200000000530358 9200000000530358
5 9200000000530343 !!Nos Vemos! 9200000000530342 9200000000530358
6 1001004011099420 Russian Dat 34388968 34388968
7 1001004011099421 Russian Dat 35434738 34388968