{
    "summary": [
        {
            "name": "audit_log",
            "title": "审计日志表(append-only)",
            "primary": ["id"],
            "catelog": "entity"
        }
    ],
    "fields": [
        {"name": "id", "title": "主键ID", "type": "str", "length": 32, "nullable": "no"},
        {"name": "tenant_id", "title": "租户ID", "type": "str", "length": 32, "nullable": "no"},
        {"name": "entity", "title": "实体类型", "type": "str", "length": 64, "nullable": "no"},
        {"name": "entity_id", "title": "实体ID", "type": "str", "length": 64, "nullable": "no"},
        {"name": "action", "title": "动作", "type": "str", "length": 64, "nullable": "no"},
        {"name": "from_state", "title": "原状态", "type": "str", "length": 32},
        {"name": "to_state", "title": "新状态", "type": "str", "length": 32},
        {"name": "who", "title": "操作角色", "type": "str", "length": 64},
        {"name": "agent_id", "title": "操作Agent标识", "type": "str", "length": 64},
        {"name": "detail", "title": "详情", "type": "text"},
        {"name": "created_at", "title": "创建时间", "type": "timestamp", "nullable": "no"}
    ],
    "indexes": [
        {"name": "idx_al_tenant", "idxtype": "index", "idxfields": ["tenant_id"]},
        {"name": "idx_al_entity", "idxtype": "index", "idxfields": ["entity", "entity_id"]},
        {"name": "idx_al_created", "idxtype": "index", "idxfields": ["created_at"]}
    ]
}