15 lines
391 B
Ruby
15 lines
391 B
Ruby
# frozen_string_literal: true
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class AddParticipantCountToTopics < ActiveRecord::Migration[4.2]
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def up
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add_column :topics, :participant_count, :integer, default: 1
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execute "UPDATE topics SET participant_count =
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(SELECT COUNT(DISTINCT p.user_id) FROM posts AS p WHERE p.topic_id = topics.id)"
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end
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def down
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remove_column :topics, :participant_count
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end
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end
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