Не удалось выполнить: "
SELECT 
  products.creator 
FROM 
  `ru_product_category_relations` rel 
  INNER JOIN `ru_products` products ON products.id = rel.product_id 
WHERE 
  rel.product_category_id IN ()
"
You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near ')' at line 1