SQLite 3.27

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CREATE tABLE articles (id int, amount_in_stock int)
CREATE tABLE products_articles (product_id INT,article_id int)
CREATE tABLE sales (id int,product_id int,amount_required int, amount_sold int)
update articles as a
set amount_in_stock = amount_in_stock - coalesce(
  (
    select amount_required * amount_sold 
    from products_articles pa inner join sales s 
    on s.product_id = pa.product_id 
    where s.id = '4c6d35bf-994a-4689-a32e-5d8196b24b06'
      and article_id = a.id
 ), 0)