How to pivot data in SQL with multiple conditions - sql

Question

I am working on a data where it looks like this
I want to pivot it in this way :
I have written in this way :
select *
from (select * FROM records) as test
PIVOT (
max(value) for
[Question_ID] in ((SELECT distinct [Question_ID] from records order by 1))) AS PivotTable
Can you please help me?

Answer 1

If you know the number of columns in PIVOT, you can directly hardcode like below.
SELECT * FROM
(
SELECT * FROM test
) t
PIVOT (
MAX(value) for
[Question_ID] in ([120],[122],[149],[150],[151],[189],[253],[554],[774] )) AS Pivot_Table
If not,you have to use Dynamic Pivot table for unknown number of column values.
DECLARE
#columns NVARCHAR(MAX) = '',
#sql NVARCHAR(MAX) = '';
-- select the QuestionIDs
SELECT
#columns+=QUOTENAME(Question_ID) + ','
FROM
test
GROUP BY Question_ID
ORDER BY Question_ID;
-- remove the last comma
SET #columns = LEFT(#columns, LEN(#columns) - 1);
-- construct dynamic SQL
SET #sql ='
SELECT * FROM
(
SELECT * FROM TEST
) t
PIVOT(
MAX(value) for
[Question_ID] IN ('+ #columns +')
) AS pivot_table;';
-- execute the dynamic SQL
EXECUTE sp_executesql #sql;
CHECK DEMO HERE

Answer 2

you got your wish result
select *
from (select * FROM #temp) as test--your table name replace with #temp
PIVOT (
max(value) for
[Question_ID] in ([120],[122],[149],[150],[151],[189],[253],[554],[774] )) AS PivotTable
or if you want to dynamic your query
DECLARE #cols AS NVARCHAR(MAX),
#query AS NVARCHAR(MAX);
SET #cols = STUFF((SELECT distinct ',' + QUOTENAME(Question_ID)
FROM #temp c
FOR XML PATH(''), TYPE
).value('.', 'NVARCHAR(MAX)')
,1,1,'')
--print #cols
set #query = 'SELECT ID, ' + #cols + ' from
(
select ID
, Question_ID
, [Value]
from #temp
) x
pivot
(
max([Value])
for [Question_ID] in (' + #cols + ')
) p '
execute(#query)
drop table #temp
----------

Answer 3

If you are sure that the number of columns will not change, then you can use case statement
CREATE TABLE #TBL (ID INT, Question_ID INT, [Value] VARCHAR(20))
INSERT INTO #TBL VALUES
(1,149,'abc'),(1,150,'def'),(1,151,'aff'),(1,122,'www'),
(2,120,'add'),(2,150,'sub'),(2,189,'asf'),(3,253,'asd'),
(3,150,'gfre'),(3,554,'cvew'),(3,744,'qwert')
-- aNSWER
SELECT
ID,
MAX(CASE WHEN Question_ID = 149 THEN [Value] END) AS '149',
MAX(CASE WHEN Question_ID = 150 THEN [Value] END) AS '150',
MAX(CASE WHEN Question_ID = 151 THEN [Value] END) AS '151',
MAX(CASE WHEN Question_ID = 122 THEN [Value] END) AS '122',
MAX(CASE WHEN Question_ID = 120 THEN [Value] END) AS '120',
MAX(CASE WHEN Question_ID = 150 THEN [Value] END) AS '150',
MAX(CASE WHEN Question_ID = 189 THEN [Value] END) AS '189',
MAX(CASE WHEN Question_ID = 253 THEN [Value] END) AS '253',
MAX(CASE WHEN Question_ID = 150 THEN [Value] END) AS '150',
MAX(CASE WHEN Question_ID = 554 THEN [Value] END) AS '554',
MAX(CASE WHEN Question_ID = 744 THEN [Value] END) AS '744'
FROM #TBL
GROUP BY ID
DROP TABLE #TBL
Output
ID 149 150 151 122 120 150 189 253 150 554 744
1 abc def aff www NULL def NULL NULL def NULL NULL
2 NULL sub NULL NULL add sub asf NULL sub NULL NULL
3 NULL gfre NULL NULL NULL gfre NULL asd gfre cvew qwert