给出两个表,一个为客户订单,列 OrderID,客户ID,和订单日期,一个为订单项,列 OrderID,产品ID,和数量,写一个SQL查询,以找到每个客户在过去一个月中产生的总收入,包括客户已放置的所有订单的收入,即使它们是在不同的日期.
Here's the SQL query to find the total revenue generated by each customer in the past month:

```
SELECT Orders.CustomerID, SUM(Items.Quantity * Products.Price) AS Revenue
FROM Orders
JOIN Items ON Orders.OrderID = Items.OrderID
JOIN Products ON Items.ProductID = Products.ProductID
WHERE Orders.OrderDate >= DATEADD(month, -1, GETDATE())
GROUP BY Orders.CustomerID
ORDER BY Revenue DESC;
```

This query joins the Orders, Items, and Products tables together based on the OrderID and ProductID columns. It then calculates the revenue for each order by multiplying the quantity of each item by the price of the product, and sums up the revenue for all orders placed by each customer in the past month. Finally, the results are grouped by customer and sorted in descending order of revenue.