sql comma delimited list of a column in analytical function - sql

Question

I am using SQL server 2008, and I need to make a common delimeted list of a column. I know how to do it, but I need this time while I use analytical function, I mean I don't want to use group by clause.
Since I will also select the records in outer query "where row_num=1"
Here is the query:
SELECT UserId
,ProductList
,Value
FROM
(
SELECT p.UserId
,p.Value
, ROW_NUMBER()OVER (PARTITION BY p.UserId ORDER BY p.RecordCreateDate asc) AS 'row_num'
--here I need a solution OVER (PARTITION BY p.UserId) AS 'ProductList'
FROM Products p
INNER JOIN
Users u
ON p.UserId = u.Id
) result
WHERE result.row_num = 1
Users data:
Id Name ....
1 John
2 Anton
3 Craig
Products data:
Id UserId Name RecordCreateDate Value
1 1 a 21.12.2012 10
2 1 b 11.12.2012 20
3 1 c 01.12.2012 30
4 2 e 05.12.2012 40
5 2 f 17.12.2012 50
6 3 d 21.12.2012 60
7 3 i 31.12.2012 70
I need a result such as:
UserId ProductList Value
1 a,b,c 30
2 e,f 40
3 d,i 60
Thanks for your help

Answer 1

Since you are going to filter on row_num = 1 you need to put your query in a CTE or the likes where you include the extra columns from Products. Then you can build your comma separated string in the outer query using the for XML path trick without using group by.
;WITH C as
(
SELECT p.UserId
, ROW_NUMBER()OVER (PARTITION BY p.UserId ORDER BY p.RecordCreateDate asc) AS 'row_num'
--, Some other fields from Products
FROM Products p
INNER JOIN
Users u
ON p.UserId = u.Id
)
SELECT UserId,
--, Some other fields from Products
--, Build the concatenated list here using for xml path()
FROM C
WHERE C.row_num = 1

Answer 2

Just for completeness. Remove the # symbols for your actual solution.
SET NOCOUNT ON;
CREATE TABLE #users
(
Id INT,
Name VARCHAR(32)
);
INSERT #users VALUES
(1,'John'),
(2,'Anton'),
(3,'Craig');
CREATE TABLE #products
(
Id INT,
UserId INT,
Name VARCHAR(32),
RecordCreateDate DATE,
Value INT
);
INSERT #products VALUES
(1,1,'a','2012-12-21',10),
(2,1,'b','2012-12-11',20),
(3,1,'c','2012-12-01',30),
(4,2,'e','2012-12-05',40),
(5,2,'f','2012-12-17',50),
(6,3,'d','2012-12-21',60),
(7,3,'i','2012-12-31',70);
The query:
;WITH x AS
(
SELECT UserId, Value,
row_num = ROW_NUMBER() OVER
(
PARTITION BY UserId
ORDER BY RecordCreateDate
)
FROM #products
)
SELECT
x.UserId,
u.Name,
ProductList = STUFF((
SELECT ',' + Name
FROM #Products AS p
WHERE p.UserId = x.UserId
FOR XML PATH(''),
TYPE).value(N'./text()[1]', N'varchar(max)'),1,1,''),
x.Value
FROM x
INNER JOIN #users AS u
ON x.UserId = u.Id
WHERE x.row_num = 1;
Then clean up:
DROP TABLE #users, #products;
Results:
UserId Name ProductList Value
1 John a,b,c 30
2 Anton e,f 40
3 Craig d,i 60

Answer 3

I'm not sure what you're asking in the beginning, but this will give you the requested output
SELECT UserId,
STUFF((SELECT ',' + ProductName from Products p WHERE p.UserID = u.UserID FOR XML PATH('')), 1, 1, '') as ProductList
FROM Users u