postgresql order by open and closing date

Question

my table looks like this:

   eventname varchar(255)
   open int unixtimestamp
   close int unixtimestamp

i like to sort the table by soonest, which means if its a coming event (open and close < now()) PostgreSQL should order the table by open, but if its a current or past event (close > now()) it should order the table by close

i tried to archive this with following order by clause:

   ORDER BY case when close>1423053440 and open>1423053440 then 'open desc' else 'close desc' END

which basically don't work, because the planer don't support asc/desc decoration inside a order by case

any hints highly appreciated

best regards

andreas

Answer 1

Use multiple keys:

ORDER BY (case when close > 1423053440 and open > 1423053440 then 1 else 2 end),
         (case when close > 1423053440 and open > 1423053440 then open end) desc,
         close asc;

The first expression puts the opens first. The second orders the open s descending. The third orders the rest using close .