SSRS - Group_Concat Еквивалент с помощта на израз?

опитайте нещо подобно (работи на SQL Server 2005 и по-нова версия):

set nocount on;
declare @t table (id int, name varchar(20), x char(1))
insert into @t (id, name, x)
select 1,'test1', 'a' union
select 1,'test1', 'b' union
select 1,'test1', 'c' union
select 2,'test2', 'a' union
select 2,'test2', 'c' union
select 3,'test3', 'b' union
select 3,'test3', 'c' 
SET NOCOUNT OFF

SELECT p1.id, p1.name,
          stuff(
                   (SELECT
                        ', ' + x
                        FROM @t p2
                        WHERE p2.id=p1.id
                        ORDER BY name, x
                        FOR XML PATH('') 
                   )
                   ,1,2, ''
               ) AS p3
      FROM @t p1
     GROUP BY 
        id, name

ИЗХОД:

id          name                 p3
----------- -------------------- ---------
1           test1                a, b, c
2           test2                a, c
3           test3                b, c

(3 row(s) affected)