with b as (
select name, value, rownumber() over (partition by name order by value) rn
from my_table
)
, c(name, value, rn) as (
select name, cast(value as varchar( 128 )) value, rn
from b
where rn= 1 
  union all
select c.name, c.value||', '||b.value, b.rn
from b, c
where b.name=c.name and b.rn=c.rn+ 1 
)
select c.name, c.value
from c
join (
select name, max(rn) rn from c group by name
) g on c.name=g.name and c.rn=g.rn
order by c.name