Question

我正在编写一个查询，我需要根据几列中的内容返回一个标签。以下是列示例。

Source Table

我需要返回的是所有在代理商列中只有a1的帐户，然后分配未指定的标签，其中a1在其中一个代理商列中，另一个代理商名称（ex a3）在一个在其他列中，将分配部分指定的标签。

下面的

将是结果的列。

[结果标签] [2]

基本的IIF或Switch功能似乎无法满足需求，因为每个标签都有多个标准可以满足。

附加表信息。 Additional Table information

Answer 1

为了在Access中获得所需的结果，我会尝试解除第一个表的转动，并获得每个代理商的最小值和最大值：

SELECT A.[Account#], MIN(A.Agency) AS MinAgency, MAX(A.Agency) AS MaxAgency
FROM
(

    SELECT B.[Account#], B.Agency1 AS Agency
    FROM SourceTable AS B
    UNION
    SELECT C.[Account#], C.Agency2
    FROM SourceTable AS C
    UNION
    SELECT D.[Account#], D.Agency3
    FROM SourceTable AS D

) AS A
GROUP BY A.[Account#]

我可能将此查询保存为＆＃34; MinMaxAgencyQuery＆＃34;然后用它来创建我的＆＃34;字母类型＆＃34;柱。然后，我将在联合查询中构建此列，如下所示：

SELECT E.[Account#], "Undesignated" AS [Letter Type]
FROM SourceTable AS E LEFT JOIN MinMaxAgencyQuery AS A ON E.[Account#] = A.[Account#]
WHERE MinAgency = "a1" AND MaxAgency = "a1"

UNION

SELECT E.[Account#], "PartiallyDesignated" AS [Letter Type]
FROM SourceTable AS E LEFT JOIN MinMaxAgencyQuery AS A ON E.[Account#] = A.[Account#]
WHERE MinAgency = "a1" AND MaxAgency <> "a1"

UNION

SELECT E.[Account#], "Designated" AS [Letter Type]
FROM SourceTable AS E LEFT JOIN MinMaxAgencyQuery AS A ON E.[Account#] = A.[Account#]
WHERE MinAgency > "a1"

当然，这个解决方案依赖于＆＃34; a1＆＃34;实际上是＆＃34; a1＆＃34; （因此，在进行字符串比较时，比其他代理商少。）

如果我需要在同一个查询中执行所有操作，我会在三个联合查询中的每一个中替换我的第一个查询，如下所示：

SELECT E.[Account#], "Undesignated" AS [Letter Type]
FROM SourceTable AS E LEFT JOIN (
SELECT A.[Account#], MIN(A.Agency) AS MinAgency, MAX(A.Agency) AS MaxAgency
    FROM
    (

        SELECT B.[Account#], B.Agency1 AS Agency
        FROM SourceTable AS B
        UNION
        SELECT C.[Account#], C.Agency2
        FROM SourceTable AS C
        UNION
        SELECT D.[Account#], D.Agency3
        FROM SourceTable AS D

    ) AS A
GROUP BY A.[Account#]

) AS F ON E.[Account#] = F.[Account#]
WHERE MinAgency = "a1" AND MaxAgency = "a1"

UNION

SELECT E.[Account#], "PartiallyDesignated" AS [Letter Type]
FROM SourceTable AS E LEFT JOIN (
SELECT A.[Account#], MIN(A.Agency) AS MinAgency, MAX(A.Agency) AS MaxAgency
    FROM
    (

        SELECT B.[Account#], B.Agency1 AS Agency
        FROM SourceTable AS B
        UNION
        SELECT C.[Account#], C.Agency2
        FROM SourceTable AS C
        UNION
        SELECT D.[Account#], D.Agency3
        FROM SourceTable AS D

    ) AS A
GROUP BY A.[Account#]

) AS F ON E.[Account#] = F.[Account#]
WHERE MinAgency = "a1" AND MaxAgency <> "a1"

UNION

SELECT E.[Account#], "Designated" AS [Letter Type]
FROM SourceTable AS E LEFT JOIN (
SELECT A.[Account#], MIN(A.Agency) AS MinAgency, MAX(A.Agency) AS MaxAgency
    FROM
    (

        SELECT B.[Account#], B.Agency1 AS Agency
        FROM SourceTable AS B
        UNION
        SELECT C.[Account#], C.Agency2
        FROM SourceTable AS C
        UNION
        SELECT D.[Account#], D.Agency3
        FROM SourceTable AS D

    ) AS A
GROUP BY A.[Account#]

) AS F ON E.[Account#] = F.[Account#]
WHERE MinAgency > "a1"

您从未指定过没有代理商1，代理商2和代理商3的帐户的内容，因此在给定此解决方案的情况下不会显示这些内容。

Access查询

1 个答案: