Concatenate a column value across multiple rows - PDW

Question

We are using PDW based on SQL2014. We require an efficient logic on how to concatenate a column value across multiple rows. We have the following table
T1
(CompanyID, StateCD)
Having following rows:
1              NY
1              NJ
1              CT
2              MA
2              NJ
2              VA
3              FL
3              CA
We need a code snippet which will return following result set:
1                    
CT,NJ,NY
2                    
MA,NJ,VA
3                    
CA,FL
We have tried built-in function STUFF with FOR XML PATH clause and it is not supported in PDW. So, we need a fast alternative.

Answer 1

Hi Try this:
SELECT * INTO #ABC
FROM 
SELECT 1 AS ID,'NY' AS NAME
UNION 
SELECT 1 AS ID,'NJ' AS NAME
UNION 
SELECT 1 AS ID,'CT' AS NAME
UNION 
SELECT 2 AS ID,'MA' AS NAME
UNION 
SELECT 2 AS ID,'NJ' AS NAME
UNION 
SELECT 2 AS ID,'VA' AS NAME
UNION 
SELECT 3 AS ID,'FL' AS NAME
UNION 
SELECT 3 AS ID,'CA' AS NAME
)A
CREATE TABLE ##CDB (ID INT, NAME NVARCHAR(800)) 
DECLARE @TMP VARCHAR(MAX), 
        @V_MIN INT,
@V_MAX INT,
@V_COUNT INT
SELECT @V_MIN=MIN(ID),@V_MAX=MAX(ID) FROM #ABC 
SET @V_COUNT=@V_MIN
WHILE @V_COUNT<=@V_MAX
BEGIN
SET @TMP = '' SELECT @TMP = @TMP + CONVERT(VARCHAR,NAME) + ', ' FROM #ABC 
WHERE ID=@V_COUNT
INSERT INTO ##CDB (ID, NAME) SELECT @V_COUNT AS ID ,CAST(SUBSTRING(@TMP, 0, LEN(@TMP)) AS VARCHAR(8000)) AS NAME 
SET @V_COUNT=@V_COUNT+1
END
SELECT * FROM ##CDB
OR
SELECT * INTO #ABC
FROM 
SELECT 1 AS ID,'NY' AS NAME
UNION 
SELECT 1 AS ID,'NJ' AS NAME
UNION 
SELECT 1 AS ID,'CT' AS NAME
UNION 
SELECT 2 AS ID,'MA' AS NAME
UNION 
SELECT 2 AS ID,'NJ' AS NAME
UNION 
SELECT 2 AS ID,'VA' AS NAME
UNION 
SELECT 3 AS ID,'FL' AS NAME
UNION 
SELECT 3 AS ID,'CA' AS NAME
UNION 
SELECT 5 AS ID,'LG' AS NAME
UNION 
SELECT 5 AS ID,'AP' AS NAME
)A
CREATE TABLE ##CDB (ID INT, NAME NVARCHAR(800)) 
DECLARE @TMP VARCHAR(MAX), 
        @V_MIN INT,
@V_MAX INT,
@V_COUNT INT
SELECT @V_MIN=MIN(ID),@V_MAX=MAX(ID) FROM #ABC 
SET @V_COUNT=@V_MIN
WHILE @V_COUNT<=@V_MAX
BEGIN
SET @TMP = '' SELECT @TMP = @TMP + CONVERT(VARCHAR,NAME) + ', ' FROM #ABC 
WHERE ID=@V_COUNT
SELECT @V_COUNT AS ID ,CAST(SUBSTRING(@TMP, 0, LEN(@TMP)) AS VARCHAR(8000)) AS NAME INTO #TEMP 
INSERT INTO ##CDB (ID, NAME) SELECT ID, NAME FROM #TEMP WHERE NAME<>''
DROP TABLE #TEMP
SET @V_COUNT=@V_COUNT+1
END
SELECT * FROM ##CDB
Thanks Shiven:) If Answer is Helpful, Please Vote