SQL Server 2008 query to convert column values to different columns dynamically - sql-server-2008

Question

I have a table like below:
panelistId DTTM
337322 7/27/2014 19:39
337322 7/27/2014 19:29
317420 7/27/2014 10:22
317420 7/27/2014 10:22
317420 7/27/2014 9:27
336333 7/27/2014 5:41
336333 7/27/2014 3:26
336333 7/27/2014 3:26
336333 7/27/2014 1:25
I am looking for a SQL select query to have below fields from this table:
panelistId | #ofExposures | Exposure_DTTM1 | Exposure_DTTM2 | Exposure_DTTM3 | Exposure_DTTM4 | Exposure_DTTM5 | etc
337322 | 2 | 7/27/2014 19:39 | 7/27/2014 19:29 | | |
Here number of DTTM will be different for each id. If an id will have only 3 DTTM then for rest of the DTTM columns it can be blank.

Answer 1

This should do the trick. Hope it helps
DECLARE #Table2 TABLE (RowID INT IDENTITY(1, 1),
panelistId INT ,
#ofExposures VARCHAR(MAX),
Exposure_DTTMVARCHAR(MAX))
DECLARE #Table TABLE (ID INT ,
DTTM VARCHAR(30)) INSERT INTO #Table (ID,
DTTM) VALUES ('337322', '7/27/2014 19:39'), ('337322', '7/27/2014 19:29'), ('317420', '7/27/2014 10:22'), ('317420', '7/27/2014 10:22'), ('317420', '7/27/2014 9:27'), ('336333', '7/27/2014 5:41'), ('336333', '7/27/2014 3:26'), ('336333', '7/27/2014 3:26'), ('336333', '7/27/2014 1:25'); WITH cte_StageOne
AS (
SELECT ROW_NUMBER() OVER(PARTITION BY id ORDER BY CAST(t.DTTM AS DATETIME) ) AS OrderID, *
FROM #Table AS t
)
INSERT INTO #Table2
SELECT MAX(ID) AS panelistId,
MAX(OrderID) AS #ofExposures,
STUFF((
SELECT ' | ' + cso.DTTM
FROM cte_StageOne AS cso
WHERE ocso.ID = cso.ID
FOR XML PATH('')
), 1, 3, '') AS #Exposure
FROM cte_StageOne AS ocso
GROUP BY ID
--SELECT * FROM #Table2
DECLARE #MaxDTTM INT DECLARE #StartLoop INT DECLARE #EndLoop INT DECLARE #ColumnList VARCHAR(MAX)
SELECT #MaxDTTM = MAX(#ofExposures),
#EndLoop = MAX(RowID),
#StartLoop = MIN(RowID) FROM #Table2
SET #ColumnList = 'panelistId|#ofExposures|Exposure_DTTM1'
WHILE #StartLoop <= #EndLoop
BEGIN
SET #ColumnList = #ColumnList + '|Exposure_DTTM' + CAST(#StartLoop + 1 AS VARCHAR(3))
SET #StartLoop = #StartLoop + 1
END SET #ColumnList = #ColumnList
SET #StartLoop = 1
WHILE #StartLoop <= #EndLoop
BEGIN
DECLARE #in_panelistId VARCHAR(10)
DECLARE #in_ofExposures VARCHAR(10)
DECLARE #in_Exposure_DTTM VARCHAR(MAX)
SELECT #in_panelistId = panelistId,
#in_ofExposures = #ofExposures,
#in_Exposure_DTTM = Exposure_DTTM
FROM #Table2
WHERE RowID = #StartLoop
SET #ColumnList = #ColumnList + CHAR(13) + CHAR(10) + #in_panelistId + '|' + #in_ofExposures + '|' + #in_Exposure_DTTM + REPLICATE('|', #MaxDTTM - #in_ofExposures)
--PRINT REPLICATE('|',#MaxDTTM - #in_ofExposures)
SET #StartLoop = #StartLoop + 1
END PRINT #ColumnList