public void SetInventory(int productId, int quantity)
 {
     var prod = GetProductById(productId);
     using (MySqlProductsDb Db = new MySqlProductsDb(ConnectionString))
     {
         if (prod != null)
         {
             Db.Products.Attach(prod);
             prod.Inventory = quantity;
             Db.Entry(prod).Property("Inventory").IsModified = true;
             Db.SaveChanges();
         }
     }
 }