Transpose rows into columns dynamically in SQL Server - sql

Question

I want to transpose the below rows dynamically into columns.
**Process Id Attribute Values**
1 Equipment Normal
1 Complaints No
1 Availability 30 min
2 Phone[phone]
2 Phone[phone]
I have tried to pivot it but I am unable to get the desired results. I need the below output
Process ID Attribute1 Value1 Arrtibute2 Value2 Attribute3 Value3
1 Equipment Normal Complaints No Availability 30 min
2 Phone[phone] Phone[phone] NULL NULL
One process can have one or more attributes. So if a process have 10 attributes, it should create 10 columns in the desired output. Any suggestions?

Answer 1

All the newest ANSI compliant databases should support this. Witn no DBMS, I stick to the newest ANSI standard.
WITH
-- your input
input(Process_Id,Attribute,Values) AS (
SELECT 1,'Equipment','Normal'
UNION ALL SELECT 1,'Complaints','No'
UNION ALL SELECT 1,'Availability','30 min'
UNION ALL SELECT 2,'Phone1','123456789'
UNION ALL SELECT 2,'Phone2','987654321'
)
,
-- need a sequence counter ...
with_seq AS (
SELECT
ROW_NUMBER() OVER(PARTITION BY process_id) AS seq
, *
FROM input
)
SELECT
process_id
, MAX(CASE seq WHEN 1 THEN attribute END) AS attrib1
, MAX(CASE seq WHEN 1 THEN values END) AS val1
, MAX(CASE seq WHEN 2 THEN attribute END) AS attrib2
, MAX(CASE seq WHEN 2 THEN values END) AS val2
, MAX(CASE seq WHEN 3 THEN attribute END) AS attrib3
, MAX(CASE seq WHEN 3 THEN values END) AS val3
FROM with_seq
GROUP BY process_id;
-- out process_id | attrib1 | val1 | attrib2 | val2 | attrib3 | val3
-- out ------------+-----------+-----------+------------+-----------+--------------+-------
-- out 1 | Equipment | Normal | Complaints | No | Availability | 30 min
-- out 2 | Phone1 | 123456789 | Phone2 | 987654321 | |

Answer 2

Try this below code. It will provide desired output.
My sample Algorithm
1. Create manual named columns by using ROW_NUMBER()
2. Create Dynamic columns for Attribute,Value named as #columnsAttribute, #columnsValue
3. Create Dynamic group by columns for both Attribute & Value named as #Allcolumns
4. Dynamic query creation with pivot for both Attribute & Value
declare #tblAttribute as
table(processid int,
attribute NVARCHAR(100),
value NVARCHAR(200))
insert into #tblAttribute(processid,attribute,value)
values(1,'Equipment','Normal'),
(1,'Complaints','No'),
(1,'Availability','30 min'),
(1,'test','testvalue'),
(2,'Phone1','123456789'),
(2,'Phone2','987654321')
;with ctetbl as
(
select ROW_NUMBER() over (partition by processid order by processid) rno,* from #tblAttribute
)
,ctetbl1 as
(
select processid,
'Attribute'+ cast(rno as NVARCHAR(2)) as DynamicAttribute,
'Value'+cast(rno as NVARCHAR(2)) as DyanamicValue
,attribute,value from ctetbl
)
select * into #tblDynamicAttribute from ctetbl1
declare #Allcolumns as NVARCHAR(max),
#columnsAttribute as NVARCHAR(max),
#columnsValue as NVARCHAR(max),
#sql as NVARCHAR(MAX) = ''
select #Allcolumns=coalesce(#Allcolumns+',','')+'max('+QUOTENAME(B.DynamicAttribute)+') as '+ QUOTENAME(B.DynamicAttribute) +',max('+QUOTENAME(B.DyanamicValue)+') as '+ QUOTENAME(B.DyanamicValue)
from (select distinct DynamicAttribute,DyanamicValue from #tblDynamicAttribute) as B
order by b.DynamicAttribute
select #columnsAttribute=coalesce(#columnsAttribute+',','')+QUOTENAME(B.DynamicAttribute)
from (select distinct DynamicAttribute,DyanamicValue from #tblDynamicAttribute) as B
order by b.DynamicAttribute
select #columnsValue=coalesce(#columnsValue+',','')+QUOTENAME(B.DyanamicValue)
from (select distinct DynamicAttribute,DyanamicValue from #tblDynamicAttribute) as B
order by b.DynamicAttribute
-- construct dynamic SQL
SET #sql ='
select x.processid,' + #Allcolumns +' from (
SELECT processid,' + #columnsAttribute+','+ #columnsValue +' FROM
(
SELECT
processid,attribute,value,dynamicattribute,DyanamicValue
FROM
#tblDynamicAttribute p
) t
PIVOT(
max(attribute)
FOR dynamicattribute IN ('+ #columnsAttribute +')
) AS pivot_table
PIVOT(
max(value)
FOR DyanamicValue IN ('+ #columnsValue +')
) AS pivot_table1
) x group by processid;';
-- execute the dynamic SQL
EXECUTE sp_executesql #sql;
drop table #tblDynamicAttribute
Sample Output