create view community_view as with all_community as ( select *, (select name from user_ u where c.creator_id = u.id) as creator_name, (select name from category ct where c.category_id = ct.id) as category_name, (select count(*) from community_follower cf where cf.community_id = c.id) as number_of_subscribers, (select count(*) from post p where p.community_id = c.id) as number_of_posts, (select count(*) from comment co, post p where c.id = p.community_id and p.id = co.post_id) as number_of_comments from community c ) select ac.*, u.id as user_id, cf.id::boolean as subscribed from user_ u cross join all_community ac left join community_follower cf on u.id = cf.user_id and ac.id = cf.community_id union all select ac.*, null as user_id, null as subscribed from all_community ac ; create view community_moderator_view as select *, (select name from user_ u where cm.user_id = u.id) as user_name, (select name from community c where cm.community_id = c.id) as community_name from community_moderator cm; create view community_follower_view as select *, (select name from user_ u where cf.user_id = u.id) as user_name, (select name from community c where cf.community_id = c.id) as community_name from community_follower cf;