SQL 枢轴问题

Question

如果你能帮忙的话。代码生成错误： 消息 8156，第 16 层，状态 1，第 236 行 为“piv1”多次指定了“Classification_Value_Id”列。

我在 SQL Server 上执行此操作。代码步骤如下： 1. 将源表 DB.[dbo].[Classification] 中的数据反透视成一列 2. 将此未透视数据加入到名为 DB.dbo.[Classification_Value] 的表中，以将列“cv.Classification_Name”返回/添加到数据集中 3. 透视这个数据集（这是返回错误的部分）

代码：

SELECT
       activityCode
     , actjvPartnerRef
     , actMonth
     , actSalesChannel
     , addCBPCharge
     , agentId
     , appType
     , areaCode

--SELECT
--polRef,[Arrangement_Id],UnpivotedData.Classification_Value_Id,UnpivotedData.Classification_Scheme_Id,ColValues, ColNames,cv.Classification_Name

FROM
(
    SELECT top 10
           [polRef]
         , [Arrangement_Id]
         , [Classification_Scheme_Id]
         , [Classification_Value_Id]
       -- ,[Arrangement_Classification_Type_Id]
       -- ,[Effective_TimeStamp]
       -- ,[End_date]
         , CAST((ISNULL([character_measure],'')) AS NVARCHAR(MAX)) AS character_measure
         , CAST((ISNULL([datetime_measure],'')) AS NVARCHAR(MAX)) AS datetime_measure
         , CAST([decimal_measure] AS NVARCHAR(MAX)) AS decimal_measure
         , CAST((ISNULL([integer_measure],'')) AS NVARCHAR(MAX)) AS integer_measure
         , CAST((ISNULL([logical_measure],'')) AS NVARCHAR(MAX)) AS logical_measure
         , CAST((ISNULL([charmax_measure],'')) AS NVARCHAR(MAX)) AS charmax_measure
         , CAST((ISNULL([long_measure],'')) AS NVARCHAR(MAX)) AS long_measure
      FROM DB.[dbo].[Classification] 
) AS SrcDataConverted

UNPIVOT
(
ColValues FOR ColNames IN
(
     character_measure
   , datetime_measure
   , decimal_measure
   , integer_measure
   , logical_measure
   , charmax_measure
   , long_measure
)
) AS UnpivotedData

LEFT JOIN DB.dbo.[Classification_Value] cv
ON  cv.[Classification_Scheme_Id] = UnpivotedData.[Classification_Scheme_Id]
AND cv.Classification_Value_Id = UnpivotedData.Classification_Value_Id

PIVOT
(MAX(ColValues) for Classification_Name in (
    activityCode
  , actjvPartnerRef
  , actMonth
  , actSalesChannel
  , addCBPCharge
  , agentId
  , appType
  , areaCode
)) AS piv1; 

任何帮助将不胜感激

谢谢

Answer 1

StuarLC: 另一个派生表需要在开始重新 PIVOT 之前包装 UNPIVOT 的结果，因为连接引入了重复的 Classification_Value_Id 和 Classification_Scheme_id，这是连接所必需的。

select 
       activityCode
     , actjvPartnerRef
     , actMonth
     , actSalesChannel
     , addCBPCharge
     , agentId
     , appType
     , areaCode
from (
   SELECT polRef
        , [Arrangement_Id]
        , UnpivotedData.Classification_Value_Id
        , UnpivotedData.Classification_Scheme_Id
        , ColValues
        , ColNames
        , Classification_Name
    FROM (
        SELECT [polRef]
             , [Arrangement_Id]
             , [Classification_Scheme_Id]
             , [Classification_Value_Id]
             , CAST((ISNULL([character_measure],'')) AS NVARCHAR(MAX)) AS character_measure
             , CAST((ISNULL([datetime_measure],'')) AS NVARCHAR(MAX)) AS datetime_measure
             , CAST([decimal_measure] AS NVARCHAR(MAX)) AS decimal_measure
             , CAST((ISNULL([integer_measure],'')) AS NVARCHAR(MAX)) AS integer_measure
             , CAST((ISNULL([logical_measure],'')) AS NVARCHAR(MAX)) AS logical_measure
             , CAST((ISNULL([charmax_measure],'')) AS NVARCHAR(MAX)) AS charmax_measure
             , CAST((ISNULL([long_measure],'')) AS NVARCHAR(MAX)) AS long_measure
          FROM DB.[dbo].[Classification] 
    ) AS SrcDataConverted
    UNPIVOT
    (
        ColValues FOR ColNames IN
        (
             character_measure
           , datetime_measure
           , decimal_measure
           , integer_measure
           , logical_measure
           , charmax_measure
           , long_measure
        )
    ) AS UnpivotedData
    LEFT JOIN 
        DB.dbo.[Classification_Value] cv
    ON  cv.[Classification_Scheme_Id] = UnpivotedData.[Classification_Scheme_Id]
    AND cv.Classification_Value_Id = UnpivotedData.Classification_Value_Id
) as src
PIVOT
(   
    MAX(ColValues) for Classification_Name in (
            activityCode
          , actjvPartnerRef
          , actMonth
          , actSalesChannel
          , addCBPCharge
          , agentId
          , appType
          , areaCode
    )
) AS piv1;