{
  "dataset": "act-air-quality",
  "from": "2026-10-03",
  "to": "2026-10-04",
  "rows_from": 386799,
  "rows_to": 386883,
  "key": [],
  "schema": {
    "fields_added": [],
    "fields_removed": [],
    "fields_retyped": []
  },
  "note": "No key is declared, so rows are compared by count only."
}