{
    "summary": [
        {
            "name": "contract_attachment",
            "title": "合同附件表",
            "primary": "id"
        }
    ],
    "fields": [
        {
            "name": "id",
            "title": "附件ID",
            "type": "str",
            "length": 32,
            "nullable": "no",
            "comments": "附件ID，主键"
        },
        {
            "name": "contract_id",
            "title": "合同ID",
            "type": "str",
            "length": 32,
            "nullable": "no",
            "comments": "关联的合同ID，引用contract表的id"
        },
        {
            "name": "file_name",
            "title": "文件名",
            "type": "str",
            "length": 255,
            "nullable": "no",
            "comments": "文件名"
        },
        {
            "name": "file_path",
            "title": "文件路径",
            "type": "str",
            "length": 500,
            "nullable": "no",
            "comments": "文件存储路径"
        },
        {
            "name": "file_size",
            "title": "文件大小",
            "type": "long",
            "nullable": "no",
            "comments": "文件大小（字节）"
        },
        {
            "name": "file_type",
            "title": "文件类型",
            "type": "str",
            "length": 50,
            "nullable": "no",
            "comments": "文件类型（MIME类型）"
        },
        {
            "name": "version",
            "title": "版本号",
            "type": "long",
            "nullable": "no",
            "default": "1",
            "comments": "文件版本号"
        },
        {
            "name": "description",
            "title": "附件描述",
            "type": "str",
            "length": 200,
            "nullable": "yes",
            "comments": "附件描述"
        },
        {
            "name": "uploaded_by",
            "title": "上传人",
            "type": "str",
            "length": 32,
            "nullable": "no",
            "comments": "上传人，引用users表的id"
        },
        {
            "name": "org_id",
            "title": "所属组织",
            "type": "str",
            "length": 32,
            "nullable": "no",
            "comments": "所属组织"
        },
        {
            "name": "created_at",
            "title": "上传时间",
            "type": "timestamp",
            "nullable": "no",
            "comments": "上传时间"
        }
    ],
    "indexes": [
        {
            "name": "idx_attachment_contract",
            "idxtype": "index",
            "idxfields": ["contract_id"]
        },
        {
            "name": "idx_attachment_org",
            "idxtype": "index",
            "idxfields": ["org_id"]
        },
        {
            "name": "idx_attachment_version",
            "idxtype": "index",
            "idxfields": ["file_name", "version"]
        }
    ],
    "codes": [
        {
            "field": "uploaded_by",
            "table": "users",
            "valuefield": "id",
            "textfield": "username"
        }
    ]
}