SELECT
chd.id,
chd.date,
chd.prd_desc,
rel.cas,
rel.posibility,
rel.match_type,
chd.exporter,
chd.importer

FROM "customs_house_data" chd

LEFT JOIN (
SELECT
row_number() over(w  ORDER BY tmp.c desc) r,
round(tmp.c/(sum(tmp.c) over(w)), 4) posibility,
*
FROM (
SELECT customs_house_data_id, match_type, cas, count(*) c
FROM customs_house_data_chem_rel chd_rel
group by customs_house_data_id, cas, match_type
) tmp
WINDOW w as (partition by customs_house_data_id)
) rel
on chd.id = rel.customs_house_data_id