sorting - Elasticsearch 中的意外(不区分大小写)字符串排序

Question

我有一个在 Elasticsearch 中排序的控制台平台列表。

这是“名称”字段的映射:

{
    "name": {
        "type": "multi_field",
        "fields": {
            "name": {
                "type": "string",
                "index": "analyzed"
            },
            "sort_name": {
                "type": "string",
                "index": "not_analyzed"
            }
        }
    }
}

当我执行下面的查询时

{
  "query": {
    "match_all": {}
  },
    "sort": [
        {
          "name.sort_name": { "order": "asc" }
        }
    ],
    "fields": ["name"]
}

我得到这些结果:

{
    "took": 1,
    "timed_out": false,
    "_shards": {
        "total": 3,
        "successful": 3,
        "failed": 0
    },
    "hits": {
        "total": 17,
        "max_score": null,
        "hits": [
            {
                "_index": "platforms",
                "_type": "platform",
                "_id": "1393602489",
                "_score": null,
                "fields": {
                    "name": "GameCube"
                },
                "sort": [
                    "GameCube"
                ]
            },
            {
                "_index": "platforms",
                "_type": "platform",
                "_id": "1393602490",
                "_score": null,
                "fields": {
                    "name": "Gameboy Advance"
                },
                "sort": [
                    "Gameboy Advance"
                ]
            },


    {
            "_index": "platforms",
            "_type": "platform",
            "_id": "1393602498",
            "_score": null,
            "fields": {
                "name": "Nintendo 3DS"
            },
            "sort": [
                "Nintendo 3DS"
            ]
        },

        ...remove for brevity ...

        {
            "_index": "platforms",
            "_type": "platform",
            "_id": "1393602493",
            "_score": null,
            "fields": {
                "name": "Xbox 360"
            },
            "sort": [
                "Xbox 360"
            ]
        },
        {
            "_index": "platforms",
            "_type": "platform",
            "_id": "1393602502",
            "_score": null,
            "fields": {
                "name": "Xbox One"
            },
            "sort": [
                "Xbox One"
            ]
        },
        {
            "_index": "platforms",
            "_type": "platform",
            "_id": "1393602497",
            "_score": null,
            "fields": {
                "name": "iPhone/iPod"
            },
            "sort": [
                "iPhone/iPod"
            ]
        }
    ]
}

除了 iPhone/iPod 结果在末尾(而不是在 GameBoy Advance 之后)之外，所有内容都按预期排序 - 为什么名称中的 / 会产生影响关于排序？

谢谢

Answer 1

好吧，我发现原因与 / 无关。 ES 将按大写字母排序，然后按小写字母排序。

我在索引创建的 settings 中添加了自定义分析器:

{
    "analysis": {
        "analyzer": {
            "sortable": {
                "tokenizer": "keyword",
                "filter": [
                    "lowercase"
                ]
            }
        }
    }
}

然后在字段映射中，我将 'analyzer': 'sortable' 添加到 sort_name 多字段。