elasticsearch - Elasticsearch 唯一ID的唯一计数

Question

假设我的数据如下所示:
项目6000的文件:
{“projectId”:“6000”，“price”:500000，“bedrooms”:2，“title”:“Affordable luxury”，“area”:“A”}，
{“projectId”:“6000”，“价格”:700000，“卧室”:4，“标题”:“宽敞”，“区域”:“A”}
项目6001的文件:
{“projectId”:“6001”，“价格”:550000，“卧室”:2，“标题”:“令人惊叹”，“区域”:“A”}
{“projectId”:“6001”，“price”:650000，“bedrooms”:3，“title”:“Excellent views”。 “area”:“B”}
项目6002的文件:
{“projectId”:“6002”，“价格”:550000，“卧室”:2，“标题”:“令人惊叹”，“区域”:“B”}
{“projectId”:“6002”，“price”:650000，“bedrooms”:3，“title”:“Excellent views”。 “area”:“C”}
等等
现在，我想检索区域数，以获取存在项目的最流行区域，但仅考虑唯一的项目ID。我有这个查询:

    query = {
        "aggs": {
            "most_popular": {
                "terms": {
                    "field": "area",
                    "size": 5,
                    "order": {
                    "_count": "desc"
                    },
                }
             }
          }

结果是:
值区:[{'key':'A'，doc_count:3}，{'key':'B'，doc_count:2} ...依此类推]
但是我想要的只是每个项目的唯一计数，因此A的doc_count应该是2而不是3，即避免在同一项目中重复。
在Elasticsearch中这怎么可能？

Answer 1

You need to use bucket sort aggregation that is a parent pipelineaggregation which sorts the buckets of its parent multi-bucketaggregation

添加带有索引数据，搜索查询和搜索结果的工作示例
索引数据:

{"projectId": "6000", "price": 500000, "bedrooms": 2, "title": "Affordable luxury", "area": "A"},

{"projectId": "6000", "price": 700000, "bedrooms": 4, "title": "Spacious", "area": "A"}

{"projectId": "6001", "price": 550000, "bedrooms": 2, "title": "Stunning", "area": "A"}

{"projectId": "6001", "price": 650000, "bedrooms": 3, "title": "Excellent views". "area": "B"}

{"projectId": "6002", "price": 550000, "bedrooms": 2, "title": "Stunning", "area": "B"}

{"projectId": "6002", "price": 650000, "bedrooms": 3, "title": "Excellent views". "area": "C"}

{"projectId": "6002", "price": 500000, "bedrooms": 2, "title": "Affordable luxury", "area": "C"}

{"projectId": "6002", "price": 500000, "bedrooms": 2, "title": "Affordable luxury", "area": "C"}

搜索查询:

    {
  "size": 0,
  "aggs": {
    "most_popular": {
      "terms": {
        "field": "area",
        "size": 5
      },
      "aggs": {
        "unique": {
          "cardinality": {
            "field": "projectId"
          }
        },
        "uniqueCount_bucket_sort": {
          "bucket_sort": {
            "sort": [
              {
                "unique": {
                  "order": "asc"
                }
              }
            ]
          }
        }
      }
    }
  }
}

搜索结果:

"buckets": [
    {
      "key": "C",
      "doc_count": 3,
      "unique": {
        "value": 1
      }
    },
    {
      "key": "B",
      "doc_count": 2,
      "unique": {
        "value": 2
      }
    },
    {
      "key": "A",
      "doc_count": 3,
      "unique": {
        "value": 2
      }
    }
  ]