{
  "id": "python/sqlalchemy-transaction-already-begun",
  "signature": "sqlalchemy.exc.InvalidRequestError: A transaction is already begun on this Session",
  "signature_zh": "此会话上已开始一个事务",
  "regex": "sqlalchemy\\.exc\\.InvalidRequestError:\\ A\\ transaction\\ is\\ already\\ begun\\ on\\ this\\ Session",
  "domain": "python",
  "category": "runtime_error",
  "subcategory": null,
  "root_cause": "Calling session.begin() when a transaction is already active, often due to misuse of session context managers.",
  "root_cause_type": "generic",
  "root_cause_zh": "在事务已激活时调用 session.begin()，通常由于会话上下文管理器使用不当。",
  "versions": [
    {
      "version": "3.x",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    }
  ],
  "os_specific": {},
  "dead_ends": [
    {
      "action": "",
      "why_fails": "May rollback unintended changes.",
      "fail_rate": 0.4,
      "condition": "",
      "sources": []
    },
    {
      "action": "",
      "why_fails": "Transaction state becomes inconsistent.",
      "fail_rate": 0.8,
      "condition": "",
      "sources": []
    }
  ],
  "workarounds": [
    {
      "action": "",
      "success_rate": 0.9,
      "how": "with session.begin():\n    session.add(obj)\n# Or just use session.add and session.commit()",
      "condition": "",
      "sources": []
    },
    {
      "action": "",
      "success_rate": 0.95,
      "how": "if not session.in_transaction():\n    session.begin()",
      "condition": "",
      "sources": []
    }
  ],
  "workarounds_zh": [],
  "transition_graph": {
    "leads_to": [],
    "preceded_by": [],
    "frequently_confused_with": []
  },
  "official_doc_url": null,
  "official_doc_section": null,
  "error_code": null,
  "verification_tier": "ai_generated",
  "confidence": 0.83,
  "fix_success_rate": 0.8,
  "resolvable": "true",
  "first_seen": "2025-04-01",
  "last_confirmed": "2025-01-01",
  "last_updated": "2025-01-01",
  "evidence_count": 0,
  "tags": [],
  "locale": "en",
  "aliases": []
}