我将下面的JSON存储在一个BLOB中，在阅读了有关json_table的Oracle文档后，我无法找到获取数据的最佳方法。

{       "filters": [
            {
                "system": "Givex",
                "target_document": "timepunch",
                "type": "EXCLUSION",
                "key": "job_codes",
                "value": "MANAGER",
                "description": ""
            },
            {
                "system": "Givex",
                "target_document": "menumix",
                "type": "EXCLUSION",
                "key": "plu_list",
                "value": "4,3,5,6,3,22",
                "description": ""
            }
        ],
        "toggles": [
            {
                "system": "Givex",
                "target_document": "salesmix",
                "type": "",
                "key": "use_category_not_sub",
                "value": "true",
                "description": "Will group sales by category not subcategory"
            }
        ]
,
        "cross_references": [
            {
                "system": "Givex",
                "target_document": "salesmix",
                "type": "",
                "key": "GL_MAP",
                "values": [
                    {
                        "gl_code": "2310",
                        "txn_name": "AB GST",
                        "txn_type_id": "1"
                    },
                    {
                        "gl_code": "2310",
                        "txn_name": "AB GST",
                        "txn_type_id": "1"
                    },
                    {
                        "gl_code": "1050-1",
                        "txn_name": "AMEX",
                        "txn_type_id": "5"
                    },
                    {
                        "gl_code": "1005",
                        "txn_name": "Actual Cash On Hand",
                        "txn_type_id": "5"
                    },
                    {
                        "gl_code": "4110",
                        "txn_name": "Appetizers",
                        "txn_type_id": "0"
                    },
                    {
                        "gl_code": "2310",
                        "txn_name": "BC GST",
                        "txn_type_id": "1"
                    },
                    {
                        "gl_code": "2371",
                        "txn_name": "BC PST",
                        "txn_type_id": "1"
                    },
                    {
                        "gl_code": "2371",
                        "txn_name": "BC PST (10%)",
                        "txn_type_id": "1"
                    },
                    {
                        "gl_code": "4150",
                        "txn_name": "Banquets",
                        "txn_type_id": "0"
                    }
                    ]
                }
            ]
            }

字符串
我试图从cross_references -->values数组中以表格格式获取gl_code、txn_name和txn_type_id的输出，其中键为'GL_MAP'
我尝试过以下方法

select jt.*
from ar_test art,
json_table(art.json_data,'$.cross_references[*]' columns (value path '$.value')) jt

型
却什么也得不到，

select art.json_data.cross_references.value from ar_test art

型
返回null
和

select j.* from 
ar_test art,
json_table(art.json_data, '$.cross_references' columns (nested value columns(gl_code,txn_name,txn_type_id))) j

型
它根本不返回任何结果。
任何建议都会很有帮助，因为我是Oracle JSON的新手，有点挣扎：）
谢谢