Query: hackernews_dashboard_stories_by_hour

with data as (
  (
    select
      *
    from
      hackernews_new
    where
      $1 = 'New'
  )
  union
  (
    select
      *
    from
      hackernews_top
    where
      $1 = 'Top'
  )
  union
  (
    select
      *
    from
      hackernews_best
    where
      $1 = 'Best'
  )
)
select
  to_char(time :: timestamptz, 'MM-DD HH24:00') as hour,
  count(*)
from
  data
group by
  hour
order by
  hour;