13 lines
392 B
Ruby
13 lines
392 B
Ruby
class AddPercentRankToPosts < ActiveRecord::Migration[4.2]
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def change
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add_column :posts, :percent_rank, :float, default: 1.0
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execute "UPDATE posts SET percent_rank = x.percent_rank
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FROM (SELECT id, percent_rank()
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OVER (PARTITION BY topic_id ORDER BY SCORE DESC)
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FROM posts) AS x
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WHERE x.id = posts.id"
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end
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end
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