Correlated subquery not working in Netezza

Question

I have a query like this in Netezza, but not sure how I can rewrite it so it will work. Thanks

with dates as (
      select distinct event_date from table
     )
select event_date, 
       (select count(distinct id)
        from table 
        where event_date < dates.event_date
       )
from dates

This form of correlated query is not supported - consider rewriting

Answer 1

This would be more efficient using window functions anyway. I think the logic is:

select event_date, 
       sum(count(*)) over (order by event_date) - count(*) as events_before
from table
group by event_date