Join tables with rows to columns conversion - sql-server

Question

I have two tables:
Output need to be like this:
select CODE, NAME,
substring_index(DVAR, ',', 1) as DATA1,
(case when numc >= 2 then substring_index(substring_index(DVAR, ',', 2), ',', -1) end) as DATA2,
(case when numc >= 3 then substring_index(substring_index(DVAR, ',', 3), ',', -1) end) as DATA3,
(case when numc >= 4 then substring_index(substring_index(DVAR, ',', 4), ',', -1) end) as DATA4,
(case when numc >= 5 then substring_index(substring_index(DVAR, ',', 5), ',', -1) end) as DATA5,
(case when numc >= 6 then substring_index(substring_index(DVAR, ',', 6), ',', -1) end) as DATA6,
(case when numc >= 7 then substring_index(substring_index(DVAR, ',', 7), ',', -1) end) as DATA7,
(case when numc >= 8 then substring_index(substring_index(DVAR, ',', 8), ',', -1) end) as DATA8,
(case when numc >= 9 then substring_index(substring_index(DVAR, ',', 9), ',', -1) end) as DATA9,
(case when numc >= 10 then substring_index(substring_index(DVAR, ',', 10), ',', -1) end) as DATA10
FROM (
SELECT T2.CODE, T1.NAME, GROUP_CONCAT(T2.DATA SEPARATOR ',') AS DVAR, count(*) as numc
FROM TABLE2 AS T2
LEFT JOIN TABLE1 AS T1 ON T1.CODE=T2.CODE
GROUP BY T2.CODE
) t
I used this code in MySQL and its working.
But I don't know how to do in SQL Server 2012.

Answer 1

You can use PIVOT for a similar effect, eg
CREATE TABLE tbl1 (
Code CHAR(5) NOT NULL,
[Name] VARCHAR(20) NOT NULL
)
CREATE TABLE tbl2 (
Code CHAR(5) NOT NULL,
[Data] VARCHAR(20) NOT NULL
)
INSERT INTO tbl1 ( Code, [Name] )
VALUES
( 'ST101', 'Item1' ),
( 'ST102', 'Item2' ),
( 'ST103', 'Item3' ),
( 'ST104', 'Item4' ),
( 'ST105', 'Item5' )
INSERT INTO tbl2 ( Code, [Data] )
VALUES
( 'ST101', '12345' ),
( 'ST101', '123456' ),
( 'ST101', '123123' ),
( 'ST101', '12412' ),
( 'ST105', '123123' ),
( 'ST105', '11' ),
( 'ST105', '51231' ),
( 'ST105', '411123' ),
( 'ST103', '112312' ),
( 'ST103', '51231' ),
( 'ST103', '442424' ),
( 'ST103', '4233' ),
( 'ST103', '23123' ),
( 'ST103', '1231' ),
( 'ST104', '12312' ),
( 'ST102', '1231' ),
( 'ST102', '51231' ),
( 'ST102', '66452' ),
( 'ST102', '51115' )
GO
;WITH cte AS (
SELECT
t1.Code,
t1.[Name],
t2.[Data],
'Data' + CAST( ROW_NUMBER() OVER( PARTITION BY t1.Code ORDER BY ( SELECT NULL ) ) AS VARCHAR(20) ) rn
FROM tbl1 t1
INNER JOIN tbl2 t2 ON t1.Code = t2.Code
)
SELECT *
FROM cte
PIVOT ( MAX( Data ) For rn In ( Data1, Data2, Data3, Data4, Data5, Data6, Data7, Data8, Data9, Data10 ) ) pvt
If the number of data items is greater than 10 or unknown you should look at dynamic pivot.