数组项的弹性搜索聚合

时间:2016-01-16 12:13:24

标签: elasticsearch aggregation elasticsearch-net

下面是我的弹性文档,我想在其上发出聚合查询。

{
    "id": 1,
    "attributes":[
    {
        "fieldId": 1,
        "value": "Male"
    },
    {
        "fieldId": 2,
        "value": "12/11/2015"
    }
}

{
    "id": 2,
    "attributes":[
    {
        "fieldId": 1,
        "value": "Male"
    },
    {
        "fieldId": 2,
        "value": "11/11/2015"
    }
}

结果必须如下。

[
    {
        "key" : "Male",
        "doc_count" : 1
    }
]

[
    {
        "key" : "12/11/2015",
        "doc_count" : 1
    },
    {
        "key" : "11/11/2015",
        "doc_count" : 1
    }
]

有没有办法在弹性搜索中实现这一目标。

1 个答案:

答案 0 :(得分:3)

这是可能的。见这个例子:

我们必须将属性映射为nested类型才能正确聚合。

PUT /test
{
  "mappings": {
    "sample": {
      "properties": {
        "id": {
          "type": "integer"
        },
        "attributes": {
          "type": "nested",
          "properties": {
            "fieldId": {
              "type": "integer"
            },
            "value": {
              "type": "string",
              "index": "not_analyzed"
            }
          }
        }
      }
    }
  }
}

让我们添加您给定的测试数据:

PUT /test/sample/1
{"id":1,"attributes":[{"fieldId":1,"value":"Male"},{"fieldId":2,"value":"12/11/2015"}]}
PUT /test/sample/2
{"id":2,"attributes":[{"fieldId":1,"value":"Male"},{"fieldId":2,"value":"11/11/2015"}]}

最后让我们运行这个查询:

GET /test/_search
{
  "size": 0,
  "query": {
    "match_all": {}
  },
  "aggs": {
    "Nest": {
      "nested": {
        "path": "attributes"
      },
      "aggs": {
        "fieldIds": {
          "terms": {
            "field": "attributes.fieldId",
            "size": 0
          },
          "aggs": {
            "values": {
              "terms": {
                "field": "attributes.value",
                "size": 0
              }
            }
          }
        }
      }
    }
  }
}

它会做什么?

  1. 首先运行nested聚合,以便进入nested个对象并正确聚合。
  2. 使用terms聚合为每个fieldId创建存储桶,在您的情况下,我们会得到其中两个:12
  3. 再次为上面的每个存储桶运行terms聚合,以获得相应的值。
  4. 这就是输出。

    {
      "took": 2,
      "timed_out": false,
      "_shards": {
        "total": 5,
        "successful": 5,
        "failed": 0
      },
      "hits": {
        "total": 2,
        "max_score": 0,
        "hits": []
      },
      "aggregations": {
        "Nest": {
          "doc_count": 4,
          "fieldIds": {
            "doc_count_error_upper_bound": 0,
            "sum_other_doc_count": 0,
            "buckets": [
              {
                "key": 1,
                "doc_count": 2,
                "values": {
                  "doc_count_error_upper_bound": 0,
                  "sum_other_doc_count": 0,
                  "buckets": [
                    {
                      "key": "Male",
                      "doc_count": 2
                    }
                  ]
                }
              },
              {
                "key": 2,
                "doc_count": 2,
                "values": {
                  "doc_count_error_upper_bound": 0,
                  "sum_other_doc_count": 0,
                  "buckets": [
                    {
                      "key": "11/11/2015",
                      "doc_count": 1
                    },
                    {
                      "key": "12/11/2015",
                      "doc_count": 1
                    }
                  ]
                }
              }
            ]
          }
        }
      }
    }
    

    这并不是你要求的。但这与Elasticsearch最接近的是什么。