在某個月發生的訂單總結價格

Question

我在查詢時遇到困難，我有大量的訂單，我正在從中提取月份和年份，並且需要將每個月內的所有價格總和和一年。我可以想出一個解決方案的唯一方法是遍歷並進行大量昂貴的比較，這似乎破壞了關係數據庫的目的。我正在查詢價格，因爲折扣經常應用於小計。我有所有必要的表加入並匹配，但由於價格計算，我不能使用內置的SUM（）函數。先謝謝你！

編輯：這是代碼，顯然我今天超級分散。這絕對是對我，謝謝你陪我住：

`SELECT dbo.SalesOrder.SalesOrderNo 
    ,dbo.SalesOrder.CustomerID 
    ,(dbo.InvoiceDetails.ExtendedPrice * (1 - dbo.Invoice.DiscountPct/100)) AS [Price] 
    ,dbo.Customers.NAME AS [Customer Name] 
    ,dbo.Customers.SalesRepID 
    ,dbo.Employees.FirstName + dbo.Employees.LastName AS [SalesRepName] 
    ,dbo.Estimate.DateCreated AS [Date Quoted] 
    ,dbo.SalesOrder.OrderDate AS [Date Ordered] 
    ,dbo.Invoice.BillingDate AS [Date Invoiced] 
    ,MONTH(dbo.Estimate.DateCreated) AS [Month Quoted] 
    ,MONTH(dbo.SalesOrder.OrderDate) AS [Month Ordered] 
    ,MONTH(dbo.Invoice.BillingDate) AS [Month Invoiced] 
    ,YEAR(dbo.Estimate.DateCreated) AS [Year Quoted] 
    ,YEAR(dbo.SalesOrder.OrderDate) AS [Year Ordered] 
    ,YEAR(dbo.Invoice.BillingDate) AS [Year Invoiced] 
FROM SalesOrder 
INNER JOIN Invoice ON Invoice.SalesOrderID = SalesOrder.SalesOrderID 
INNER JOIN InvoiceDetails ON InvoiceDetails.InvoiceID = Invoice.InvoiceID 
INNER JOIN Customers ON Customers.CustomerID = SalesOrder.CustomerID 
INNER JOIN SalesReps ON Customers.SalesRepID = SalesReps.SalesRepID 
INNER JOIN Employees ON Employees.EmployeeID = SalesReps.EmployeeID 
INNER JOIN Estimate ON Estimate.EstimateID = SalesOrder.EstimateID 
WHERE dbo.Invoice.Approved = '1' 
    AND (YEAR(dbo.Invoice.BillingDate) >= YEAR(GETDATE()) - 1) 
    AND (YEAR(dbo.Estimate.DateCreated) >= YEAR(GETDATE()) - 1) 
    AND (YEAR(dbo.SalesOrder.OrderDate) >= YEAR(GETDATE()) - 1)` 

Answer 1

沒有任何其他信息，是有一個原因，你不能做這樣的事？

SELECT YEAR(ORDER_DATE) AS [Year], MONTH(ORDER_DATE) AS [Month], SUM(AMOUNT) AS [Total] 
    FROM Orders 
GROUP BY YEAR(ORDER_DATE), MONTH(ORDER_DATE) 
ORDER BY YEAR(ORDER_DATE), MONTH(ORDER_DATE) 

假設表名是「訂單」，它有列「ORDER_DATE」爲一個日期時間，和「量」的數值。

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基礎上顯示的價格計算您更新的查詢，身邊的事簡單的方式就是建立一個CTE（公共表表達式）從現有的查詢，然後選擇/ GROUP BY的.. 。是這樣的：

WITH sales AS (
    SELECT dbo.SalesOrder.SalesOrderNo 
     ,dbo.SalesOrder.CustomerID 
     ,(dbo.InvoiceDetails.ExtendedPrice * (1 - dbo.Invoice.DiscountPct/100)) AS [Price] 
     ,dbo.Customers.NAME AS [Customer Name] 
     ,dbo.Customers.SalesRepID 
     ,dbo.Employees.FirstName + dbo.Employees.LastName AS [SalesRepName] 
     ,dbo.Estimate.DateCreated AS [Date Quoted] 
     ,dbo.SalesOrder.OrderDate AS [Date Ordered] 
     ,dbo.Invoice.BillingDate AS [Date Invoiced] 
     ,MONTH(dbo.Estimate.DateCreated) AS [Month Quoted] 
     ,MONTH(dbo.SalesOrder.OrderDate) AS [Month Ordered] 
     ,MONTH(dbo.Invoice.BillingDate) AS [Month Invoiced] 
     ,YEAR(dbo.Estimate.DateCreated) AS [Year Quoted] 
     ,YEAR(dbo.SalesOrder.OrderDate) AS [Year Ordered] 
     ,YEAR(dbo.Invoice.BillingDate) AS [Year Invoiced] 
    FROM SalesOrder 
    INNER JOIN Invoice ON Invoice.SalesOrderID = SalesOrder.SalesOrderID 
    INNER JOIN InvoiceDetails ON InvoiceDetails.InvoiceID = Invoice.InvoiceID 
    INNER JOIN Customers ON Customers.CustomerID = SalesOrder.CustomerID 
    INNER JOIN SalesReps ON Customers.SalesRepID = SalesReps.SalesRepID 
    INNER JOIN Employees ON Employees.EmployeeID = SalesReps.EmployeeID 
    INNER JOIN Estimate ON Estimate.EstimateID = SalesOrder.EstimateID 
    WHERE dbo.Invoice.Approved = '1' 
     AND (YEAR(dbo.Invoice.BillingDate) >= YEAR(GETDATE()) - 1) 
     AND (YEAR(dbo.Estimate.DateCreated) >= YEAR(GETDATE()) - 1) 
     AND (YEAR(dbo.SalesOrder.OrderDate) >= YEAR(GETDATE()) - 1) 
) 
SELECT [Month Ordered], [Year Ordered], SUM([Price]) AS TotalOrderedPrice 
    FROM Sales 
GROUP BY [Month Ordered], [Year Ordered] 
ORDER BY [Month Ordered], [Year Ordered] 

這將創建一個名爲「銷售」使用原始查詢verbatum CTE，然後使用在選擇CTE，在底部做分組和排序上（包括求和計算出的價格）關於該查詢的結果。這是一種簡單的'語法糖'，它使得表達這種東西比如果你不得不重做查詢來總結計算值或子選擇或者你有什麼要容易得多，並且是一種有用的技巧。