This was one possible solution that a friend very familiar with
PostgreSQL ( the target db in this question btw) came up with. I repeat it
here just for informational purposes.

select s.id, s.date, s.price from stock s,
(select id, min(price) as price from stock group by id) as m
where s.id = m.id and s.price = m.price
and s.date = (select max(x.date) from stock x
where x.price = m.price and x.id = m.id);


Eric:
I really don't understand your solution, could you give me the plain english desrciption of what its doing?

Thanks Mike