post_id int references post on update cascade on delete cascade not null,
fedi_user_id text not null,
score smallint not null, -- -1, or 1 for dislike, like, no row for no opinion
- published timestamp not null default now()
+ published timestamp not null default now(),
+ unique(post_id, fedi_user_id)
);
+
--- /dev/null
+-- Rank = ScaleFactor * sign(Score) * log(1 + abs(Score)) / (Time + 2)^Gravity
+create or replace function hot_rank(
+ score numeric,
+ published timestamp without time zone)
+returns numeric as $$
+begin
+ -- hours_diff:=EXTRACT(EPOCH FROM (timezone('utc',now()) - published))/3600
+ return 10000*sign(score)*log(1 + abs(score)) / power(((EXTRACT(EPOCH FROM (timezone('utc',now()) - published))/3600) + 2), 1.8);
+end; $$
+LANGUAGE plpgsql;
+
+create view post_listing as
+select post.*,
+(select count(*) from comment where comment.post_id = post.id) as number_of_comments,
+coalesce(sum(post_like.score),0) as score,
+hot_rank(coalesce(sum(post_like.score),0), post.published) as hot_rank
+from post
+left join post_like
+on post.id = post_like.post_id
+group by post.id;