これは、テーブルの単純な内部結合です:
SELECT m.name, cp.id_category
FROM manufacturer as m
INNER JOIN product as p
ON m.id_manufacturer = p.id_manufacturer
INNER JOIN category_product as cp
ON p.id_product = cp.id_product
WHERE cp.id_category = 'some value'
これは、テーブルの単純な内部結合です:
SELECT m.name, cp.id_category
FROM manufacturer as m
INNER JOIN product as p
ON m.id_manufacturer = p.id_manufacturer
INNER JOIN category_product as cp
ON p.id_product = cp.id_product
WHERE cp.id_category = 'some value'