DELETE FROM custom_attribute_definitions
WHERE attribute_model = 'conversation_attribute'
  AND attribute_name IN (
      'swt_source_url',
      'swt_source_search_term',
      'swt_source_purchase_term',
      'swt_source_keyword_id',
      'swt_source_channel',
      'swt_source_realtime_location',
      'swt_source_region',
      'swt_source_ad_account_id',
      'swt_source_wakeable',
      'swt_baidu_conversation_type',
      'swt_baidu_agent_name',
      'swt_baidu_ssid'
  );

-- Conversation values are retained to avoid losing source-attribution data.