Question

在以下查询中，我得到的子查询返回的值更多1。当子查询遵循=，！=，＆lt;，＆lt; =，＆gt;，＆gt; =或子查询用作表达式时，不允许这样做。错误

SELECT  MemberID,
        FirstName,
        MiddleName,
        LastName,
        (FirstName+' '+LastName) AS FullName,
        Gender,
        CASE    Gender
        WHEN    1 THEN  'Male'
        ELSE    'Female' END AS GenderName,
        Phone1,
        MemberNumber,
        MembershipTypeID,
        (   SELECT  MembershipTypeName
            FROM    MembershipTypeMaster
            WHERE   MembershipTypeID    =   MemberDetails.MembershipTypeID ) AS MemberType,
        (   SELECT  MaxCreditLimit
            FROM    MembershipTypeMaster
            WHERE   MembershipTypeID    =   MemberDetails.MembershipTypeID ) AS MaxCreditLimit,
        (   SELECT  DepositAmount
            FROM    MemberCreditInfo
            WHERE   MemberID    =   MemberDetails.MemberID ) AS DepositAmount,
        Phone1,
        Phone2,
        Mobile,
        EMail,
        HouseNumber,
        City,
        MemberDetailsState,
        (   HouseNumber+','+City+','+MemberDetailsState+','+PinCode ) AS Address,
        PinCode,
        MemberPhoto,
        MemberStatus,
        ISNULL((    SELECT  ( MaxCreditLimit - UsedCredit )
            FROM    MemberCreditInfo    
            WHERE   MemberID =  MemberDetails.MemberID ),0) AS BalanceCredit,
        ISNULL((    SELECT  UsedCredit
            FROM    MemberCreditInfo    
            WHERE   MemberID =  MemberDetails.MemberID ),0) AS BalanceToPay
  FROM  MemberDetails
  WHERE MemberStatus <> 99

Answer 1

这是关于你的内部选择查询。

例如，如果以下查询返回多个结果，则sql无法知道它应该写入MemberType单元格。

( SELECT  MembershipTypeName
        FROM    MembershipTypeMaster
        WHERE   MembershipTypeID    =   MemberDetails.MembershipTypeID )

子查询返回了更多1个值。当子查询遵循=，！=，＆lt;，＆lt; =，＆gt;，＆gt; =或子查询用作表达式时，不允许这样做

1 个答案: