使用 LEFT JOIN 时，MS Access 2016“不支持 JOIN 表达式”

Question

我试图在销售系统中获得未结余额。我通过组合 3 个表来做到这一点，因为它是多对多的关系。根据 MSDN

“左连接或右连接可以嵌套在内部连接中，但是 INNER JOIN 不能嵌套在 LEFT JOIN 或 RIGHT JOIN 中"

但我在运行查询时收到错误 "JOIN expression not supported" 这是我的代码：

SELECT DISTINCTROW Table1.CustomerName, Sum(Table1.TotalAmount) AS [Total Payable Amount]
, Sum(Table2.PaidAmount) AS [Total Paid Amount]
, Sum(Table1.TotalAmount - Table2.PaidAmount) AS [Total Outstanding Balance]

FROM Table2 

INNER JOIN 
(Table1 LEFT JOIN Table3 ON Table1.InvoiceNumber =Table3.InvoiceNumber) 
ON Table2.ReceiptNumber = Table3.ReceiptNumber

GROUP BY Table1.CustomerName;

Answer 1

一种选择是将LEFT JOIN 替换为INNER JOIN，并修改ON 条件以保留来自Table1 的不匹配行，从而模拟LEFT JOIN：

SELECT DISTINCTROW Table1.CustomerName, Sum(Table1.TotalAmount) AS [Total Payable Amount],
    Sum(Table2.PaidAmount) AS [Total Paid Amount]
    Sum(Table1.TotalAmount - Table2.PaidAmount) AS [Total Outstanding Balance]
FROM Table2 
INNER JOIN 
(
    SELECT Table1.*. Table3.ReceiptNumber
    FROM Table1 INNER JOIN Table3
        ON Table1.InvoiceNumber = Table3.InvoiceNumber
    UNION
    SELECT Table1.*, NULL
    FROM Table1
    WHERE Table1.InvoiceNumber NOT IN (SELECT Table3.InvoiceNumber FROM Table3)
 )
ON Table2.ReceiptNumber = Table3.ReceiptNumber
GROUP BY Table1.CustomerName;

Answer 2

我总是在 MS Access SQL 上苦苦挣扎。但是在表设计器的一点帮助下，我想我发现了你的语法错误。尝试将 FROM 子句更改为：

FROM 
    (
        Table2 INNER JOIN Table3 ON Table2.ReceiptNumber = Table3.ReceiptNumber
    ) 
LEFT JOIN Table1 ON Table3.InvoiceNumber = Table1.InvoiceNumber;

这里的关键是重构您的查询，使 INNER 连接出现在括号内，而 LEFT 连接出现在括号外。