2017-08-31 00:06:56 -04:00
|
|
|
class AddPercentRankToPosts < ActiveRecord::Migration[4.2]
|
2013-03-22 15:43:57 -04:00
|
|
|
def change
|
|
|
|
|
add_column :posts, :percent_rank, :float, default: 1.0
|
|
|
|
|
|
|
|
|
|
execute "UPDATE posts SET percent_rank = x.percent_rank
|
|
|
|
|
FROM (SELECT id, percent_rank()
|
|
|
|
|
OVER (PARTITION BY topic_id ORDER BY SCORE DESC)
|
|
|
|
|
FROM posts) AS x
|
|
|
|
|
WHERE x.id = posts.id"
|
|
|
|
|
|
|
|
|
|
end
|
|
|
|
|
end
|
