Getting a list of text concatenated in a group by

Say I have this data:

site cell value
a    b    "1"
a    c    "2"

And I want the output for the format:

site value
a    "b=1,c=2"

Is it possible with SQL?

PS: I am using access. But even if access does n开发者_开发百科ot support this particular syntax I would like to know any database that can.

Declare @tbl table ([site] nvarchar(100),Cell nvarchar(100),Value nvarchar(100))
INSERT INTO @tbl values('A','b','1')
INSERT INTO @tbl values('A','c','2')

SELECT [Site],
SUBSTRING(
(
select ' ,'+  Cell +'=' + CAST(value AS VARCHAR)
from @tbl b
WHERE a.[Site] = b.[Site]
FOR XML PATH('')
)
,3,100)

FROM @tbl a
GROUP BY a.[Site]

It is possible to do this in MySQL with GROUP_CONCAT