21 lines
762 B
MySQL
21 lines
762 B
MySQL
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-- Rank = ScaleFactor * sign(Score) * log(1 + abs(Score)) / (Time + 2)^Gravity
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create or replace function hot_rank(
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score numeric,
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published timestamp without time zone)
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returns numeric as $$
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begin
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-- hours_diff:=EXTRACT(EPOCH FROM (timezone('utc',now()) - published))/3600
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return 10000*sign(score)*log(1 + abs(score)) / power(((EXTRACT(EPOCH FROM (timezone('utc',now()) - published))/3600) + 2), 1.8);
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end; $$
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LANGUAGE plpgsql;
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create view post_listing as
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select post.*,
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(select count(*) from comment where comment.post_id = post.id) as number_of_comments,
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coalesce(sum(post_like.score),0) as score,
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hot_rank(coalesce(sum(post_like.score),0), post.published) as hot_rank
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from post
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left join post_like
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on post.id = post_like.post_id
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group by post.id;
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