恐怕这是不可能的，因为字段标签不是ES保存或albiet创建倒排索引的字段。

Doc doc['fieldname'] 仅适用于创建倒排索引的字段，Elasticsearch 的查询 DSL 也仅适用于创建倒排索引的字段，不幸的是，嵌套类型不是创建倒排索引的有效字段。

话虽如此，我有以下两种方法。

为了简单起见，我创建了示例映射、文档和两个可能对您有帮助的解决方案。

PUT my_sample_index
{
  "mappings": {
    "properties": {
      "myfield": {
        "type": "nested",
        "properties": {
          "label": {
            "type": "keyword"
          }
        }
      }
    }
  }
}

// single field inside 'myfield'
POST my_sample_index/_doc/1
{
  "myfield": {                              
    "label": ["New York", "LA", "Austin"]   
  }
}


// two fields inside 'myfield' 
POST my_sample_index/_doc/2
{                                          
  "myfield": {                             
    "label": ["London", "Leicester", "Newcastle", "Liverpool"],
    "country": "England"
  }
}

我有一个解决方法来获得您想要的内容，但不完全是，但可以帮助您过滤掉服务层或应用程序。

POST my_sample_index/_search
{
  "_source": "*", 
  "query": {
    "bool": {
      "must": [
        {
          "match_all": {}
        }
      ]
    }
  },
  "script_fields": {
    "label_size": {
        "script": {
            "lang": "painless",
            "source": "params['_source']['labels'].size() > 1"
        }
    }
  }
}

您会注意到，作为响应，会使用true或false值创建一个单独的字段label_size。

示例响应如下：

{
  "took" : 5,
  "timed_out" : false,
  "_shards" : {
    "total" : 1,
    "successful" : 1,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : {
      "value" : 2,
      "relation" : "eq"
    },
    "max_score" : 1.0,
    "hits" : [
      {
        "_index" : "my_sample_index",
        "_type" : "_doc",
        "_id" : "1",
        "_score" : 1.0,
        "_source" : {
          "myfield" : {
            "label" : [
              "New York",
              "LA",
              "Austin"
            ]
          }
        },
        "fields" : {
          "label_size" : [              <---- Scripted Field
            false
          ]
        }
      },
      {
        "_index" : "my_sample_index",
        "_type" : "_doc",
        "_id" : "2",
        "_score" : 1.0,
        "_source" : {
          "myfield" : {
            "country" : "England",
            "label" : [
              "London",
              "Leicester",
              "Newcastle",
              "Liverpool"
            ]
          }
        },
        "fields" : {                  <---- Scripted Field
          "label_size" : [
            true                      <---- True because it has two fields 'labels' and 'country'
          ]
        }
      }
    ]
  }
}

注意，只有第二个文档才有意义，因为它有两个字段，即国家和标签。但是，如果您只希望具有＜code＞label_size＜/code＞且＜code＞true＜/code＜的文档，则必须在应用程序层进行管理。

创建新索引，如下所示：

PUT my_sample_index_temp
{
  "mappings": {
    "properties": {
      "myfield": {
        "type": "nested",
        "properties": {
          "label": {
            "type": "keyword"
          }
        }
      },
      "labels_size":{             <---- New Field where we'd store the size
        "type": "integer"
      }
    }
  }
}

创建以下管道:

PUT _ingest/pipeline/set_labels_size
{
  "description": "sets the value of labels size",
  "processors": [
      {
        "script": {
          "source": """
            ctx.labels_size = ctx.myfield.size();
          """
        }
      }
    ]
}

使用重新索引API从< code>my_sample_index索引重新索引

POST _reindex
{
  "source": {
    "index": "my_sample_index"
  },
  "dest": {
    "index": "my_sample_index_temp",
    "pipeline": "set_labels_size"
  }
}

使用GETmy_sample_index_temp/_search验证my_sample_index_temp中的文档

{
  "took" : 1,
  "timed_out" : false,
  "_shards" : {
    "total" : 1,
    "successful" : 1,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : {
      "value" : 2,
      "relation" : "eq"
    },
    "max_score" : 1.0,
    "hits" : [
      {
        "_index" : "my_sample_index_temp",
        "_type" : "_doc",
        "_id" : "1",
        "_score" : 1.0,
        "_source" : {
          "labels_size" : 1,           <---- New Field Created 
          "myfield" : {
            "label" : [
              "New York",
              "LA",
              "Austin"
            ]
          }
        }
      },
      {
        "_index" : "my_sample_index_temp",
        "_type" : "_doc",
        "_id" : "2",
        "_score" : 1.0,
        "_source" : {
          "labels_size" : 2,           <----- New Field Created
          "myfield" : {
            "country" : "England",
            "label" : [
              "London",
              "Leicester",
              "Newcastle",
              "Liverpool"
            ]
          }
        }
      }
    ]
  }
}

现在，您可以在查询中简单地使用这个字段< code>labels_size,这种方式更简单，效率更高。

希望这有所帮助！

您可以使用自定义分数方法解决它：

GET 2019-11-04/_search
{
  "min_score": 0.1,
  "query": {
    "function_score": {
      "query": {
        "match_all": {}
      },
      "functions": [
        {
          "script_score": {
            "script": {
              "source": "params['_source']['labels'].length > 10 ? 1 : 0"
            }
          }
        }
      ]
    }
  }
}