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IF OBJECT_ID('tempdb..#Pivot_data')IS NOT NULL
DROP TABLE #Pivot_data
IF OBJECT_ID('tempdb..#tab')IS NOT NULL
DROP TABLE #tab
select * into #tab from
(select 'a'AS COL1,'b'AS COL2,'c'AS COL3,'a'AS COL4,'c'AS COL5,'c' COL6)AS A
DECLARE @Columns nvarchar(max) ,@QUERY NVARCHAR(MAX)
;WITH CTE AS (
SELECT COLUMNSS,COL_VALUES,ROW_NUMBER()OVER(PARTITION BY COL_VALUES ORDER BY (SELECT 1))RN FROM (
SELECT * FROM #tab
)AS A
UNPIVOT(COL_VALUES FOR COLUMNSS IN([col1],[col2],[col3],[col4],[col5],[col6])) AS B
)
,FINAL_Result as (select COLUMNSS,COL_VALUES from CTE where RN=1)
SELECT * INTO #Pivot_data FROM FINAL_Result
SET @Columns= (SELECT STUFF((SELECT ',['+COLUMNSS+']' FROM #Pivot_data FOR XML PATH('')),1,1,''))
SET @QUERY=N'SELECT * FROM (
SELECT * FROM #Pivot_data
) AS A
PIVOT (MAX(COL_VALUES)FOR COLUMNSS IN('+@Columns+'))
AS B'
PRINT @QUERY
EXEC (@QUERY)
Logic :
From the given table i did unpivot and generated a Row_number() based on the column values and considered only which are Row_num=1 i.e Distinct columns values . and finally, i Pivoted the resultant data .
GROUP