попробуйте что-то вроде этого (работает на SQL Server 2005 и выше):
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
ВЫХОД:
id name p3
----------- -------------------- ---------
1 test1 a, b, c
2 test2 a, c
3 test3 b, c
(3 row(s) affected)