{
  "id": "go/database-sql-conn-max-lifetime",
  "signature": "sql: connection has been closed",
  "signature_zh": "sql: 连接已关闭",
  "regex": "sql:\\ connection\\ has\\ been\\ closed",
  "domain": "go",
  "category": "data_error",
  "subcategory": null,
  "root_cause": "A database connection is used after it has been closed due to exceeding ConnMaxLifetime, causing errors on subsequent queries.",
  "root_cause_type": "generic",
  "root_cause_zh": "由于超过 ConnMaxLifetime，数据库连接被关闭后仍被使用，导致后续查询出错。",
  "versions": [
    {
      "version": "1.22",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    }
  ],
  "os_specific": {},
  "dead_ends": [
    {
      "action": "",
      "why_fails": "Can cause stale connections and resource leaks.",
      "fail_rate": 0.7,
      "condition": "",
      "sources": []
    },
    {
      "action": "",
      "why_fails": "database/sql manages connections; manual reuse is not supported.",
      "fail_rate": 0.9,
      "condition": "",
      "sources": []
    }
  ],
  "workarounds": [
    {
      "action": "",
      "success_rate": 0.85,
      "how": "db.SetConnMaxLifetime(30 * time.Minute); db.SetMaxOpenConns(100); db.SetMaxIdleConns(10)",
      "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": "2024-08-12",
  "last_confirmed": "2025-01-01",
  "last_updated": "2025-01-01",
  "evidence_count": 0,
  "tags": [],
  "locale": "en",
  "aliases": []
}