sql - 如何在 MS Access SQL 中获取总量？

Question

我使用以下查询来获取 OrderID:

SELECT OrderItem.ID
     , ProductID
     , OrderID
     , Quantity
     , P.Title
     , P.CurrentPrice
     , P.ID
     , (P.CurrentPrice* OrderItem.Quantity) AS Total
FROM OrderItem
INNER JOIN Product AS P
   ON OrderItem.ProductID = P.ID

如何获取每个 OrderID 的总金额(将所有具有相同 OrderID 的总计相加)？

Answer 1

您可以使用选择表单进行选择和分组

select OrderID, sum(Total) 
from (
SELECT 
    OrderItem.ID
    , ProductID
    , OrderID
    , Quantity
    , P.Title
    ,P.CurrentPrice
    , P.ID
    , (P.CurrentPrice* OrderItem.Quantity) AS Total
FROM OrderItem 
INNER JOIN Product AS P ON OrderItem.ProductID = P.ID
) t 
group by OrderId