Need help with my WHERE criteria

Question

The following SQL will give me everything from the bjob table for a bjob_id.
select * from bjob
where bjob_id = 5855
I would like to add additional criteria to select the row where the column bjob_end_date is null. If there is no bjob_end_date that is null I would like to select the greatest (most recent) bjob_activity_date.
In pseudo code:
If a row has a null bjob_end_date, use this row.
If there are no rows with a null bjob_end_date, use the row with the greatest bjob_activity_date
I know this is not correct, but something like:
and (bjob_end_date is null) or (SELECT MAX(bjob_activity_date) FROM bjob where bjob_id = 5855)

Answer 1

user11944006 wrote:
An error is returned. I must be missing something. No, it's me:
select  *
  from  (
         select  b.*,
                 row_number() over(order by bjob_activity_date desc nulls first) rn
           from  bjob b
           where bjob_id = 5855
  where rn = 1
/ SY.