I hardly get hard time to come up with the title of the blog post. This was one of the blog post even though simple, I believe I have not come up with appropriate title: Group by Rows and Columns using XML PATH – Efficient Concatenating Trick. Anyway, here is the question I received.
“I have a table of students and the courses they are enrolled with the name of the professor besides it. I would like to group the result with course and instructor name.
For example, here is my table:
How can I generate result as following?
“
Now you can see how easy the question is but so hard to come up with either solution or the title of this blog post. We can use XML PATH and come up with the solution where we combine two or more columns together and display desired result.
Here is the quick script which does the task, ask, I have used temporary tables so you can just take this script and quickly run on your machine and see how it returns results.
Let me know if there are any better ways to do the same.
-- Create table
CREATE TABLE #TestTable (StudentName VARCHAR(100), Course VARCHAR(100),
Instructor VARCHAR(100), RoomNo VARCHAR(100))
GO
-- Populate table
INSERT INTO #TestTable (StudentName, Course, Instructor, RoomNo)
SELECT 'Mark', 'Algebra', 'Dr. James', '101'
UNION ALL
SELECT 'Mark', 'Maths', 'Dr. Jones', '201'
UNION ALL
SELECT 'Joe', 'Algebra', 'Dr. James', '101'
UNION ALL
SELECT 'Joe', 'Science', 'Dr. Ross', '301'
UNION ALL
SELECT 'Joe', 'Geography', 'Dr. Lisa', '401'
UNION ALL
SELECT 'Jenny', 'Algebra', 'Dr. James', '101'
GO
-- Check orginal data
SELECT *
FROM #TestTable
GO
-- Group by Data using column and XML PATH
SELECT
StudentName,
STUFF((
SELECT ', ' + Course + ' by ' + CAST(Instructor AS VARCHAR(MAX)) +
' in Room No ' + CAST(RoomNo AS VARCHAR(MAX))
FROM #TestTable
WHERE (StudentName = StudentCourses.StudentName)
FOR XML PATH (''))
,1,2,'') AS NameValues
FROM #TestTable StudentCourses
GROUP BY StudentName
GO
-- Clean up
DROP TABLE #TestTable
GO
Reference: Pinal Dave (https://blog.sqlauthority.com)
24 Comments. Leave new
This is not working when applied on Views. Do you know why?
Hi pinaldave,
I have Data in table like:
col1 Col2 Col3 Col4 Col5
1 2 3 4 3/8/2013
0 4 2 5 3/16/2013
1 2 3 0 3/8/2013
1 2 3 0 3/16/2013
Need query which output will be like:
Col 6 3/8/2013 3/16/2013
Col1 Sum(col1 on above date) =2 Sum(col1 on above date)=1
col2 Sum(col2 on above date) = 4 Sum(col2 on above date)=6
col3 Sum(col3 on above date) = 6 Sum(col3 on above date)=5
col4 Sum(col4 on above date) = 4 Sum(col4 on above date) = 5
with temp(col6,col7,col8)
as
(
select ‘col1’ as ‘col6′,case when col5=’3/8/2013’ then sum(col1) else ” end as ‘3/8/2013′,
case when col5 =’3/16/2013’ then sum(col1) else ” end as ‘3/16/2013’
from #TestTable1
group by col5
union
select ‘col2’ as ‘col6′,case when col5=’3/8/2013’ then sum(col2) else ” end as ‘3/8/2013′,
case when col5 =’3/16/2013’ then sum(col2) else ” end as ‘3/16/2013’
from #TestTable1
group by col5
union
select ‘col3’ as ‘col6′,case when col5=’3/8/2013’ then sum(col3) else ” end as ‘3/8/2013′,
case when col5 =’3/16/2013’ then sum(col3) else ” end as ‘3/16/2013’
from #TestTable1
group by col5
union
select ‘col4’ as ‘col6′,case when col5=’3/8/2013’ then sum(col4) else ” end as ‘3/8/2013′,
case when col5 =’3/16/2013’ then sum(col4) else ” end as ‘3/16/2013’
from #TestTable1
group by col5
)
select col6,SUM(col7) as ‘3/8/2013’,SUM(col8) as ‘3/16/2013’ from temp
group by col6
Good stuff! Thank you!
Thanks a lot!
Wow. Thanks.
Is there a way to put the Stuff-part in a function?
Can anyone please explain me the meaning of – FOR XML PATH (”))
,1,2,”) ???
For xml path is used to return tables data in xml formate and at the last 1,2 is used with STUFF ( character_expression , start , length , replaceWith_expression )
I need to collect all the parentmenuid from child id. For example below is my table
ID MenuCaption ParentMenuID
1 Home NULL
2 ClientAdmin 1
3 Mastersetup 2
4 Page1 3
5 Setting 4
I expecting result set as below when i give child’s parent id (4)
ID MenuCaption ParentMenuID
1 Home NULL
2 ClientAdmin 1
3 Mastersetup 2
4 Page1 3
Great post. How can I reverse the order in which the values are concatenated?
You can use ORDER BY with the stuffed for xml SELECT just as you can with any SELECT.
I have did it..
SELECT *
FROM (
SELECT
QID,[Option],
Total
FROM
(
select QID, case OPID
when 1 then ‘OP1’
when 2 then ‘OP2’
when 3 then ‘OP3’
when 4 then ‘OP4’
when 5 then ‘OP5’
END as [Option] ,Count(UID) as Total from UserResponse group by QID,OPID
)as T
) as s
PIVOT
(
SUM(Total)
FOR [Option] IN(OP1,OP2,OP3,OP4,OP5)
)AS PivotTable
Just awesome I was trying to create a JSON for child parent so I wanted region–>territories this STUFF worked like charm great
Thanks @raveendra
not working for sql server 2008. any alternative????
What is not working? Any error?
It works perfectly for me on SQL Server 2008. As always, thank you for your article
Thank you
Great! Its working fine in SQL2012, I tried few more method to achieve your requirement, but dint able to find the better solution.
Thanks for your article.
Thanks @Jagdeep
This does not work as the lists get truncated at about 256 characters
Thank you so much sir