Question

我正在使用MS Visual Studio 2012.我遇到了编写子查询的问题。这是整个查询，如下所示：

SELECT ACCOUNTNUM
    , NAME
    , ADDRESS
    , PHONE
    , TELEFAX
    , INVOICEACCOUNT
    , CUSTGROUP
    , PAYMTERMID
    , CURRENCY
    , DIMENSION
    , CELLULARPHONE
    , STATISTICSGROUP
    , PAYMMODE
    , NAMEALIAS
    , CONTACTPERSONID
    , STREET
    , PARTYID
    , SEGMENTID
    , TAXGROUP
    , DATAAREAID
    , ISNULL((
            SELECT PERCENT1 AS DiscCount
            FROM PRICEDISCTABLE
            WHERE (DATAAREAID = CUSTTABLE.DATAAREAID)
                AND (ACCOUNTRELATION = CUSTTABLE.ACCOUNTNUM)
            ), 0) / 100 AS DiscCount
    , (
        SELECT NAME
        FROM CONTACTPERSON
        WHERE (DATAAREAID = CUSTTABLE.DATAAREAID)
            AND (CUSTACCOUNT = CUSTTABLE.ACCOUNTNUM)
            AND (CONTACTPERSONID = CUSTTABLE.CONTACTPERSONID)
        ) AS ContactName
    , (
        SELECT PHONE
        FROM CONTACTPERSON AS CONTACTPERSON_1
        WHERE (DATAAREAID = CUSTTABLE.DATAAREAID)
            AND (CUSTACCOUNT = CUSTTABLE.ACCOUNTNUM)
            AND (CONTACTPERSONID = CUSTTABLE.CONTACTPERSONID)
        ) AS ContactPhone
    , ISNULL((
            SELECT STATGROUPNAME
            FROM CUSTSTATISTICSGROUP
            WHERE (DATAAREAID = CUSTTABLE.DATAAREAID)
                AND (CUSTSTATISTICSGROUP = CUSTTABLE.STATISTICSGROUP)
            ), 0) AS StatisticsName
FROM CUSTTABLE
WHERE CUSTGROUP = @ty
    AND DATAAREAID = N'OTN'
    AND STATISTICSGROUP LIKE @ss;

然后我收到错误

子查询返回的值超过1。这是不允许的子查询跟随=，！=，＆lt;，＆lt; =，＆gt;，＆gt; =或当子查询用作表达。

Answer 1

问题来自哪里？

问题是你的一个子查询返回多个值（HEY，ERROR DESCRIPTION SAYS THAT）。

如何找到哪一个？

尝试在select语句中注释掉每个子查询，直到查询正常。

如何解决？

这可能是使用CROSS APPLY的最佳案例。这是你的疑问：

SELECT ACCOUNTNUM
    , NAME
    , ADDRESS
    , PHONE
    , TELEFAX
    , INVOICEACCOUNT
    , CUSTGROUP
    , PAYMTERMID
    , CURRENCY
    , DIMENSION
    , CELLULARPHONE
    , STATISTICSGROUP
    , PAYMMODE
    , NAMEALIAS
    , CONTACTPERSONID
    , STREET
    , PARTYID
    , SEGMENTID
    , TAXGROUP
    , DATAAREAID
    , ISNULL(T1.DiscCount, 0) / 100 AS DiscCount
    , T2.ContactName
    , T3.ContactPhone
    , ISNULL(T4, 0) AS StatisticsName
FROM CUSTTABLE
CROSS APPLY (
    SELECT PERCENT1 AS DiscCount
    FROM PRICEDISCTABLE
    WHERE DATAAREAID = CUSTTABLE.DATAAREAID
        AND ACCOUNTRELATION = CUSTTABLE.ACCOUNTNUM
    ) AS T1
CROSS APPLY (
    SELECT NAME
    FROM CONTACTPERSON
    WHERE DATAAREAID = CUSTTABLE.DATAAREAID
        AND CUSTACCOUNT = CUSTTABLE.ACCOUNTNUM
        AND CONTACTPERSONID = CUSTTABLE.CONTACTPERSONID
    ) AS T2
CROSS APPLY (
    SELECT PHONE
    FROM CONTACTPERSON AS CONTACTPERSON_1
    WHERE DATAAREAID = CUSTTABLE.DATAAREAID
        AND CUSTACCOUNT = CUSTTABLE.ACCOUNTNUM
        AND CONTACTPERSONID = CUSTTABLE.CONTACTPERSONID
    ) AS T3
CROSS APPLY (
    SELECT STATGROUPNAME
    FROM CUSTSTATISTICSGROUP
    WHERE DATAAREAID = CUSTTABLE.DATAAREAID
        AND CUSTSTATISTICSGROUP = CUSTTABLE.STATISTICSGROUP
    ) AS T4
WHERE CUSTGROUP = @ty
    AND DATAAREAID = N'OTN'
    AND STATISTICSGROUP LIKE @ss;

此外，这些可以重写为简单的INNER JOINS。

Answer 2

遇到此错误时，请尝试单独运行子查询，如果返回了多条记录，则优化条件以确保只返回一条记录。

当然，如果需要多条记录，则需要更改查询以使用连接而不是子查询。

SSRS“子查询返回的值超过1”

2 个答案: