left outer join only select newest record

Hi folks,

I know I've seen posts like this before but Google isn't helping today.

I have two tables, vehicle stock and tax requests. Each vehicle can be taxed
more than once, but I only want to pull in the most recent tax request - the
one with the highest ud_id.

I have the following, which obviously returning multiple records which then
appears that the same vehicle is in stock multiple times. How can I make it
so we only show each vehicle once, showing the most recent tax request
details.

select * from stock_details s
left outer join used_diary u on s.s_registration = u.ud_registration;

--
Gary Stainburn
Group I.T. Manager
Ringways Garages
http://www.ringways.co.uk