Query: hackernews_sources_domain_input

with domains as (
  select distinct
    substring(url from 'http[s]*://([^/$]+)') as domain
  from
    hackernews_new where $1 = 'New'
  union
  select distinct
    substring(url from 'http[s]*://([^/$]+)') as domain
  from
    hackernews_top where $1 = 'Top'
  union
  select distinct
    substring(url from 'http[s]*://([^/$]+)') as domain
  from
    hackernews_best where $1 = 'Best'
)
select
  domain as label,
  domain as value
from
  domains
order by
  domain