{
    "table_name": "approval_instance",
    "fields": [
        {
            "name": "id",
            "type": "varchar(32)",
            "not_null": true,
            "comment": "主键ID"
        },
        {
            "name": "workflow_id",
            "type": "varchar(32)",
            "not_null": true,
            "comment": "工作流ID"
        },
        {
            "name": "business_type",
            "type": "varchar(50)",
            "not_null": true,
            "comment": "业务类型: contract/customer/opportunity"
        },
        {
            "name": "business_id",
            "type": "varchar(64)",
            "not_null": true,
            "comment": "业务记录ID"
        },
        {
            "name": "current_step",
            "type": "int",
            "comment": "当前步骤号"
        },
        {
            "name": "status",
            "type": "varchar(20)",
            "comment": "状态: pending/approved/rejected/cancelled"
        },
        {
            "name": "initiator_id",
            "type": "varchar(32)",
            "comment": "发起人ID"
        },
        {
            "name": "org_id",
            "type": "varchar(32)",
            "comment": "组织ID"
        },
        {
            "name": "initiated_at",
            "type": "timestamp",
            "comment": "发起时间"
        },
        {
            "name": "completed_at",
            "type": "timestamp",
            "comment": "完成时间"
        }
    ],
    "indexes": [
        {
            "name": "idx_instance_workflow",
            "fields": [
                "workflow_id"
            ],
            "type": "normal"
        },
        {
            "name": "idx_instance_business",
            "fields": [
                "business_type",
                "business_id"
            ],
            "type": "normal",
            "comment": "复合索引：按业务类型和记录查询"
        },
        {
            "name": "idx_instance_status",
            "fields": [
                "status"
            ],
            "type": "normal"
        },
        {
            "name": "idx_instance_initiator",
            "fields": [
                "initiator_id"
            ],
            "type": "normal"
        }
    ],
    "codes": [
        {
            "key": "pending",
            "name": "审批中"
        },
        {
            "key": "approved",
            "name": "已通过"
        },
        {
            "key": "rejected",
            "name": "已驳回"
        },
        {
            "key": "cancelled",
            "name": "已取消"
        }
    ],
    "summary": {
        "tablename": "approval_instance",
        "label": "审批实例",
        "comment": "审批流程实例记录"
    }
}