json - Elasticsearch 的 "include_in_parent"/"include_in_root"是如何工作的？它应该显示在 '_source' 中吗？

Question

在像这样的简单 Elasticsearch 映射中:

{
    "personal_document": {
        "analyzer": "standard",
        "_timestamp": {
            "enabled": true
        },
        "properties": {
            "description": {
                "type": "multi_field",
                "fields": {
                    "sort": {
                        "type": "string",
                        "index": "not_analyzed"
                    },
                    "description": {
                        "type": "string",
                        "include_in_root": true
                    }
                }
            },
            "my_nested": {
                "type": "nested",
                "include_in_root": true,
                "properties": {
                    "description": {
                        "type": "string"
                    }
                }
            }
        }
    }
}

.... "include_in_root": true 不是应该将字段 my_nested.description 添加到根文档吗？

And during a query am I not supposed to see THAT field into the _source field?

和

Specifying an highlight directive on the field 'my_nested.description' would automatically retrieve the _included_in_root value_ instead of the nested field?

(像这样) “强调”: { “领域”:{ “描述”: {}， “my_nested.description”:{} }

---

还是我对official nested type documentation有什么误解？ ？(这个不是很清楚)

Answer 1

如果在嵌套文档上启用了 include_in_parent 或 include_in_root 选项，那么 Elasticsearch 会在内部使用父文档上展平的嵌套字段对数据进行索引。然而，这只是 Elasticsearch 内部的，您永远不会在 _source 字段中看到它们。

If the user field is of type object, this document would be indexed internally something like this...

因为它被引用 here .

因此，您通过引用嵌套文档的字段继续执行操作(如您提到的突出显示)。您引用的突出显示语法应该如下所示

"highlight": {
    "fields": {
      "my_nested.description": {}
    }
}

而不是

"highlight": {
    "fields": {
      "description": {}
    }
}