Elasticsearch boost

Question

我有一个名为find的索引和一个名为song的类型。歌曲类型结构：

    "_index": "find",
    "_type": "song",
    "_id": "192108",
    "_source": {
      "id": 192108,          
      "artist": "Melanie",
      "title": "Dark Night",
      "lyrics": "Hot air hangs like a dead man\nFrom a white oak tree",
      "downloadCount": 234
    }

因为多首歌曲可能有相同的字段值，所以我需要通过downloadCount这样的流行度字段来提高结果。

如何将以下查询更改为按downloadCount优化？

GET /search/song/_search
{
  "query": {
      "multi_match": {
          "query": "like a dead hangs",
          "type": "most_fields",
          "fields": ["artist","title","lyrics"],
          "operator": "or"
        }
     }
}

Answer 1

你可以使用elastic_search的field_value_factor功能，通过downloadCount来提升结果

https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-function-score-query.html#function-field-value-factor

Answer 2

您可以使用function score查询。功能评分查询通过script_score函数提供了根据单据字段对单据进行评分的接口。

{
    "query": {
        "function_score": {
            "query": {
                "bool": {
                    "must": [{
                        "term": {
                            "you_filter_field": {
                                "value": "VALUE"
                            }
                        }
                    }]
                }
            },
            "functions": [{
                "script_score": {
                    "script": "doc['downloadCount'].value"
                }
            }]
        }
    }
}

谢谢