查詢不計算Invoice_Total列的總和

Question

I want to calculate the total sum of Invoice_Total as one Sum, not per row.

SELECT YEAR(Invoice_Date)as SalesYear, MONTH(Invoice_Date)as SalesMonth, Client_Name,Invoice_Total, SUM(Invoice_Total) AS TotalSales FROM INVOICE JOIN CLIENT ON CLIENT.Client_ID= INVOICE.Client_ID WHERE Invoice_Date between '2016-01-01'and'2016-01-31' GROUP BY Client_Name, Invoice_Date, Invoice_Total;

Answer 1

如果只是想SUM作爲一個行，那麼你可以從查詢，例如刪除GROUP BY它可以是簡單的：

SELECT SUM(Invoice_Total) 
FROM INVOICE 
WHERE Invoice_Date BETWEEN '2016-01-01' AND '2016-01-31'; 

更新

如果從現有查詢（與其他列一起）要Invoice_Total的SUM，那麼你可以把它包裝成另一個查詢，例如：

SELECT SalesYear, SalesMonth, Client_Name, Invoice_Total, SUM(TotalSales) 
FROM (
SELECT YEAR(Invoice_Date)as SalesYear, MONTH(Invoice_Date)as SalesMonth, Client_Name,Invoice_Total, SUM(Invoice_Total) AS TotalSales FROM INVOICE 
JOIN CLIENT 
ON CLIENT.Client_ID= INVOICE.Client_ID 
WHERE Invoice_Date between '2016-01-01'and'2016-01-31' 
GROUP BY Client_Name, Invoice_Date, Invoice_Total 
) a; 

如果你不希望其他列（因爲它不會太大的意義與所有行打印相同的值），只需使用SELECT SUM(TotalSales) FROM...