機能ロールアウトエラー率の比較

SELECT
  feature_flag,
  cohort,
  release,
  COUNT(*) AS requests,
  SUM(CASE WHEN status = 'failed' THEN 1 ELSE 0 END) AS errors,
  100.0 * SUM(CASE WHEN status = 'failed' THEN 1 ELSE 0 END)
    / NULLIF(COUNT(*), 0) AS error_rate_pct,
  AVG(latency_ms) AS avg_latency_ms
FROM feature_rollout_events
WHERE timestamp_utc >= now() - INTERVAL '24 hours'
  AND environment = 'production'
GROUP BY feature_flag, cohort, release
ORDER BY error_rate_pct DESC, cohort;