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问题描述

我有两个这样的表:

**tblTagDescription**

在此处输入图像描述

and  **tblDataLog**

在此处输入图像描述

现在我想显示任何特定组的记录,并且在一个组中可能有多个 id 的相同组tbltagdescription。而 id oftbltagdescriptiontblDataLogas的外键TagDescID

这里“Group1”有 10 个 ID,从 1 到 10。在 tbldatalog 中这些 ID(从 1 到 10)可能有多个记录。我希望这些 ID 从 1 到作为列。为此,我使用了枢轴:

DECLARE @COlsID NVARCHAR(MAX)
DECLARE @SQL NVARCHAR(MAX)
DECLARE @Group NVARCHAR(50) = 'Group1'

IF OBJECT_ID('tempdb..##MYTABLE') IS NOT NULL 
    DROP TABLE ##MYTABLE

SELECT 
    @COlsID = COALESCE(@ColsID + '],[','') + CONVERT(NVARCHAR(5), z.TagDescID)  
FROM
    (SELECT DISTINCT TOP 50 tblDataLog.TagDescID 
     FROM tblDataLog 
     INNER JOIN tblTagDescription ON tblDataLog.TagDescID = tblTagDescription.ID 
     ORDER BY tblDataLog.TagDescID) z  

SET @COlsID='[' + @COlsID + ']'

SET @SQL='select [DATE],SHIFT, ' + @COlsID + ' into ##MYTABLE from ( select [Date], Value, 
                     (CASE  
                                WHEN ((DATEPART(hour,[DATE]))>6 and (DATEPART(hour,[DATE]))<14) THEN ''A'' 
                                WHEN ((DATEPART(hour,[DATE]))>=14 and (DATEPART(hour,[DATE]))<22) THEN ''B'' 
                                WHEN ((DATEPART(hour,[DATE]))>=22 or (DATEPART(hour,[DATE]))<6) THEN ''C'' 
                            END )AS SHIFT 

                     from tblDataLog )d pivot(max(Value) for TagDescID in (' + @COlsID + ')) piv;'

        EXEC (@SQL)

现在当我执行这个语句时,我得到一个错误:

列名“TagDescID”无效

但在tbldatalog. 如何解决这个查询?

标签: sqlsql-serversql-server-2008pivot

解决方案


您需要子查询中的 TagDescID 列。

DECLARE @COlsID NVARCHAR(MAX) = ''
DECLARE @COlsAlias NVARCHAR(MAX) = ''
DECLARE @SQL NVARCHAR(MAX)
DECLARE @Group NVARCHAR(50) = 'Group1'

SELECT 
   @COlsID = @ColsID + ',' + z.TagDescID, 
   @COlsAlias = @COlsAlias + ',' + z.TagDescID + ' AS ' + z.ReportTag   
FROM
    (SELECT DISTINCT TOP 50 tblDataLog.TagDescID ID,  QUOTENAME(CONVERT(NVARCHAR(5), tblDataLog.TagDescID )) TagDescID, QUOTENAME(tblTagDescription.ReportTag) ReportTag 
     FROM tblDataLog 
        INNER JOIN tblTagDescription ON tblDataLog.TagDescID = tblTagDescription.ID 
     ORDER BY tblDataLog.TagDescID 
     ) z

SET @COlsID= STUFF(@COlsID,1,1,'')
SET @COlsAlias= STUFF(@COlsAlias,1,1,'')

SET @SQL='select [DATE],SHIFT, ' + @COlsAlias + ' into ##MYTABLE from ( select [Date], Value, TagDescID,
                     (CASE  
                                WHEN ((DATEPART(hour,[DATE]))>6 and (DATEPART(hour,[DATE]))<14) THEN ''A'' 
                                WHEN ((DATEPART(hour,[DATE]))>=14 and (DATEPART(hour,[DATE]))<22) THEN ''B'' 
                                WHEN ((DATEPART(hour,[DATE]))>=22 or (DATEPART(hour,[DATE]))<6) THEN ''C'' 
                            END )AS SHIFT 

                     from tblDataLog )d pivot(max(Value) for TagDescID in (' + @COlsID + ')) piv;'

EXEC (@SQL)

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