按版本追蹤資料庫遷移失敗

SELECT
  release,
  service,
  database_name,
  COUNT(*) AS migrations,
  SUM(CASE WHEN status = 'success' THEN 1 ELSE 0 END) AS successful,
  SUM(CASE WHEN status = 'failed' THEN 1 ELSE 0 END) AS failed,
  SUM(CASE WHEN status = 'rolled_back' THEN 1 ELSE 0 END) AS rolled_back,
  100.0 * SUM(CASE WHEN status = 'success' THEN 1 ELSE 0 END)
    / NULLIF(COUNT(*), 0) AS success_rate_pct,
  AVG(duration_ms) AS average_duration_ms
FROM database_migration_events
WHERE timestamp_utc >= now() - INTERVAL '30 days'
  AND environment = 'production'
GROUP BY release, service, database_name
ORDER BY release DESC;