با سلام
اینجوری تغغیرش بده
SELECT Categories.CategoryID, Categories.CategoryName, Products.ProductName, Customers.CustomerID, Orders.OrderID,SUM(Products.UnitPrice)
FROM Orders INNER JOIN
Customers ON Orders.CustomerID = Customers.CustomerID INNER JOIN
[Order Details] ON Orders.OrderID = [Order Details].OrderID INNER JOIN
Categories INNER JOIN
Products ON Categories.CategoryID = Products.CategoryID ON [Order Details].ProductID = Products.ProductID
WHERE Categories.CategoryID = '4'
GROUP BY Customers.CustomerID, Categories.CategoryID, Categories.CategoryName, Products.ProductName, Orders.OrderID