SQL - Select unique rows from a group of results

Question

I have wrecked my brain on this problem for quite some time. I\'ve also reviewed other questions but was unsuccessful.

The problem I have is, I have a list of results/t

Answer 1

You want embedded queries, which not all SQLs support. In t-sql you'd have something like

select  r.registration, r.recent, t.id, t.unittype
from    ( 
    select  registration, max([date]) recent
    from    @tmp 
    group by 
        registration
    ) r
left outer join 
    @tmp t 
on  r.recent = t.[date]
and r.registration = t.registration