server/migrations/2019-05-02-051656_community_view_hot_rank/up.sql

   1 drop view community_view;
   2 create view community_view as
   3 with all_community as
   4 (
   5   select *,
   6   (select name from user_ u where c.creator_id = u.id) as creator_name,
   7   (select name from category ct where c.category_id = ct.id) as category_name,
   8   (select count(*) from community_follower cf where cf.community_id = c.id) as number_of_subscribers,
   9   (select count(*) from post p where p.community_id = c.id) as number_of_posts,
  10   (select count(*) from comment co, post p where c.id = p.community_id and p.id = co.post_id) as number_of_comments,
  11   hot_rank((select count(*) from community_follower cf where cf.community_id = c.id), c.published) as hot_rank
  12   from community c
  13 )
  14
  15 select
  16 ac.*,
  17 u.id as user_id,
  18 (select cf.id::boolean from community_follower cf where u.id = cf.user_id and ac.id = cf.community_id) as subscribed
  19 from user_ u
  20 cross join all_community ac
  21
  22 union all
  23
  24 select
  25 ac.*,
  26 null as user_id,
  27 null as subscribed
  28 from all_community ac
  29 ;