message: Update warehouse-manager.sql
diff: SELECT name AS warehouse_name,
  SUM(units*Width*LENGTH*Height) AS volume
  -FROM Warehouse
  -INNER JOIN Products ON Warehouse.product_id = Products.product_id
  +FROM Warehouse w
  +INNER JOIN Products p ON w.product_id = p.product_id
  GROUP BY name
  ORDER BY NULL;
  