10 lines
497 B
Ruby
10 lines
497 B
Ruby
class AddLastVersionAtToPosts < ActiveRecord::Migration[4.2]
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def change
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add_column :posts, :last_version_at, :timestamp
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execute "UPDATE posts SET last_version_at = COALESCE((SELECT max(created_at)
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FROM versions WHERE versions.versioned_id = posts.id
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AND versions.versioned_type = 'Post'), posts.created_at)"
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change_column :posts, :last_version_at, :timestamp, null: false
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end
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end
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