DECLARE	@TestData TABLE
(
	ID	int IDENTITY(1,1) NOT NULL,
	LinkID	int NOT NULL,
	Name	varchar(10) NOT NULL
)

INSERT INTO @TestData(LinkID, Name)
SELECT 1, 'Foo' UNION ALL
SELECT 1, 'Bar' UNION ALL
SELECT 2, 'Xxx' UNION ALL
SELECT 2, 'Yyy' UNION ALL
SELECT 3, 'Aaa' UNION ALL
SELECT 4, 'Bbb'

1, 'Foo,Bar'
2, 'Xxx,Yyy'
3, 'Aaa'
4, 'Bbb'

DECLARE	@TestData TABLE
(
	ID	int IDENTITY(1,1) NOT NULL,
	LinkID	int NOT NULL,
	Name	varchar(10) NOT NULL
)

INSERT INTO @TestData(LinkID, Name)
SELECT 1, 'Foo' UNION ALL
SELECT 1, 'Bar' UNION ALL
SELECT 2, 'Xxx' UNION ALL
SELECT 2, 'Yyy' UNION ALL
SELECT 3, 'Aaa' UNION ALL
SELECT 4, 'Bbb'

Select * from @TestData 
Declare @TestData2 table (
	LinkID	int NOT NULL,
	ConcatName varchar(100),
	Processed int
)

Insert into @TestData2 (Linkid, concatname, Processed ) 
Select distinct LinkId, NULL, 0
FROM @TestData 


Declare @val varchar(50), @Linkid int
While exists (Select * from @TestData2 Where processed = 0)
	Begin
		Select @Linkid = MIN(LinkId) FROM @TestData2 Where processed = 0
		Set @val = null
		Select @val = COALESCE(@val+', ', '') + T.Name FROM @TestData T WHERE T.LinkID = @Linkid 
		
		Update T2
		Set T2.ConcatName = @val 
		From @TestData2 T2
		Where T2.Linkid = @Linkid
		
		update @TestData2 Set Processed = 1 WHERE Linkid = @Linkid
	End

select * from @TestData2

SELECT	LinkID,
	CASE WHEN MIN(Name) <> MAX(Name) THEN MIN(Name) + ',' + MAX(Name) ELSE MIN(Name) END
FROM	@TestData
GROUP BY LinkID