查询以根据另一列的最大值填充 MS Access 中的列

Question

这是我的桌子[Property]:

Loanno  Balance amount  PropertyType
-------------------------------------
1001045 308731.770000     1
1001045 2007700.740000    2
1001045 3087318905.770    3
1001045 308731.770000     4
1001046 306589.67         1
1001046 456321.23         1
1001046 6932542.89        1
1001047 965421.34         Null
1001047 965421.34         2
1001048 567894.34         1
1001048 567894.34         2

我必须获取具有最高 balance amount 的 [Loanno] 的属性类型。如果在最高的balance amount 中有一个平局，并且如果loannumber 的Property type 不同，那么对于那个Loan number，我必须将property type 填充为“8”。所以我的最终输出应该是这样的：

Loanno  PropertyType
---------------------
1001045     3
1001046     1
1001047     1
1001048     8

这是我尝试过的查询。这是@Gord 建议的。

SELECT DISTINCT 
    [Property].Loanno, 
    IIf(Loanno_MaxBalance_Count.RowCount>1, 8, [Property].PropertyType) AS PropertyType
FROM 
    [Property]
    INNER JOIN 
    (
        SELECT 
            [Property].Loanno, 
            [Property].[Balance amount], 
            COUNT(*) AS RowCount 
        FROM 
            [Property]
            INNER JOIN
            (
                SELECT 
                    Loanno, 
                    MAX([Balance amount]) AS MaxBalance 
                FROM [Property] 
                GROUP BY Loanno
            ) AS Loanno_MaxBalance
                ON Loanno_MaxBalance.Loanno=[Property].Loanno 
                    AND Loanno_MaxBalance.MaxBalance=[Property].[Balance amount]
        GROUP BY [Property].Loanno, [Property].[Balance amount]
    ) AS Loanno_MaxBalance_Count
        ON [Property].Loanno=Loanno_MaxBalance_Count.Loanno 
            AND [Property].[Balance amount]=Loanno_MaxBalance_Count.[Balance amount]

但这里的问题是Loan no 1001047，最高的Balance amount 965421.34 是Property type 作为1 和空。因此，上面的查询返回property type 作为8。相反，我希望它是 1。一般来说，如果 Property type 不同，并且如果它不为 null 我想要 8 ，则最高 balance amount 。否则 property type 应该是一个非 NULL 值。 对此的任何帮助将不胜感激。

Answer 1

这是你想要的吗？

select LoanNo,
       iif(min(PropertyType) = max(PropertyType), min(PropertyType), 8) as PropertyType
from property as p inner join
     (select LoanNo, max(BalanceAmount) as maxba
      from property
      group by LoanNo
     ) as pmax
     on p.LoanNo = pmax.LoanNo and p.BalanceAMount = pmax.maxba
group by LoanNo;