MS-Access SQL中的子查詢語法錯誤

Question

晚上好。

我試圖創建一個查詢，平均每個產品購買VS.購買數量以獲得平均購買金額。

這包括三個表：

1. 客戶
2. 發票
3. LINE

我寫了這個：

SELECT CUSTOMER.CUS_CODE, CUS_FNAME+" "+CUS_LNAME AS Name, CUSTOMER.CUS_BALANCE,  
Sum([LINE]![LINE_NUMBER]*[LINE]![LINE_PRICE]) AS Total_purchases, 
Count(INVOICE.INV_NUMBER) AS Number_of_purchases, 

(
SELECT [Sum([LINE]![LINE_NUMBER]*[LINE]![LINE_PRICE])/ 
[Count(INVOICE.INV_NUMBER)] 
FROM INVOICE, LINE 
WHERE INVOICE.INV_NUMBER = LINE.INV_NUMBER 
) AS Average_purchase_amount 

FROM CUSTOMER, INVOICE, LINE 
WHERE CUSTOMER.CUS_CODE = INVOICE.CUS_CODE AND INVOICE.INV_NUMBER = LINE.INV_NUMBER 
GROUP BY CUSTOMER.CUS_CODE, CUS_FNAME+" "+CUS_LNAME, CUSTOMER.CUS_BALANCE; 

---

我在第二個SELECT出現錯誤。我不知道爲什麼。我覺得我錯過了很簡單的事情。

實際的錯誤讀取：！

• 「語法錯誤在查詢表達式「（ SELECT [總和（[LINE] [LINE_NUMBER] * [LINE] [LINE_PRICE]）/ [計數（ INVOICE.INV_NUMBER）。'」

從錯誤我認爲在我的表情某處的東西不排隊，但我想我沒有足夠的瞭解是怎麼回事，知道它到底是什麼。

Answer 1

有不平衡的括號。無論是每一個的意思是在方括號或整個公式：

SELECT [Sum([LINE]![LINE_NUMBER]*[LINE]![LINE_PRICE])]/[Count(INVOICE.INV_NUMBER)] 

- 或 -

SELECT [Sum([LINE]![LINE_NUMBER]*[LINE]![LINE_PRICE])/Count(INVOICE.INV_NUMBER)] 

試着加入你的表。就像這樣：

FROM INVOICE 
    INNER JOIN CUSTOMER ON CUSTOMER.CUS_CODE = INVOICE.CUS_CODE 
    INNER JOIN LINE ON LINE.INV_NUMBER =INVOICE.INV_NUMBER