基于doc_count的弹性搜索范围桶聚合

Question

我有这样一个elasticsearch聚合查询。

{
    "aggs": {
        "customer": {
            "aggs": {
                "Total_Sale": {
                    "sum": {
                        "field": "amount"
                    }
                }
            },
            "terms": {
                "field": "org",
                "size": 50000
            }
        }
    }
}

它会导致桶聚合，如下所示

{
    "aggregations": {
        "customer": {
            "buckets": [
                {
                    "Total_Sale": { "value": 9999 },
                    "doc_count": 8,
                    "key": "cats"
                },
                {
                    "Total_Sale": { "value": 8888 },
                    "doc_count": 6,
                    "key": "tigers"
                },
                {
                    "Total_Sale": { "value": 444},
                    "doc_count": 5,
                    "key": "lions"
                },
                {
                    "Total_Sale": { "value": 555 },
                    "doc_count": 2,
                    "key": "wolves"
                }
           ]
       }
    }
}

我想要另一个基于doc_count的范围桶聚合。所以，最终需要的结果是

{
    "buckets": [    
        {               
            "Sum_of_Total_Sale": 555, // If I can form bucket, I can get this using sum_bucket. So, getting bucket is important.
            "Sum_of_doc_count": 2, 
            "doc_count": 1, 
            "key": "*-3",   
            "to": 3.0       
        },              
        {               
            "Sum_of_Total_Sale": 9332,
            "Sum_of_doc_count": 11,
            "doc_count": 2, 
            "from": 4.0,    
            "key": "4-6",   
            "to": 6.0       
        },                  
        {               
            "Sum_of_Total_Sale": 9999,
            "Sum_of_doc_count": 8,
            "doc_count": 1, 
            "from": 7.0,    
            "key": "7-*"    
        }                   
    ]                   
}  

• 桶选择器聚合，然后使用桶和聚合将无法工作，因为范围有多个键。
• 桶脚本聚合在桶中进行计算。
• 我是否可以为每个文档添加脚本文档字段，以帮助我创建这些存储桶？

Answer 1

据我所知，没有聚合可以让你一举做到这一点。然而，有一种技术，我经常使用，以克服这一限制。其想法是重复相同的terms/sum聚合，然后对您感兴趣的每个范围使用bucket_selector管道聚合。

POST index/_search
{
  "size": 0,
  "aggs": {
    "*-3": {
      "terms": {
        "field": "org",
        "size": 1000
      },
      "aggs": {
        "Total_Sale": {
          "sum": {
            "field": "amount"
          }
        },
        "*-3": {
          "bucket_selector": {
            "buckets_path": {
              "docCount": "_count"
            },
            "script": "params.docCount <= 3"
          }
        }
      }
    },
    "*-3_Total_Sales": {
      "sum_bucket": {
        "buckets_path": "*-3>Total_Sale"
      }
    },
    "*-3_Total_Docs": {
      "sum_bucket": {
        "buckets_path": "*-3>_count"
      }
    },
    "4-6": {
      "terms": {
        "field": "org",
        "size": 1000
      },
      "aggs": {
        "Total_Sale": {
          "sum": {
            "field": "amount"
          }
        },
        "4-6": {
          "bucket_selector": {
            "buckets_path": {
              "docCount": "_count"
            },
            "script": "params.docCount >= 4 && params.docCount <= 6"
          }
        }
      }
    },
    "4-6_Total_Sales": {
      "sum_bucket": {
        "buckets_path": "4-6>Total_Sale"
      }
    },
    "4-6_Total_Docs": {
      "sum_bucket": {
        "buckets_path": "4-6>_count"
      }
    },
    "7-*": {
      "terms": {
        "field": "org",
        "size": 1000
      },
      "aggs": {
        "Total_Sale": {
          "sum": {
            "field": "amount"
          }
        },
        "7-*": {
          "bucket_selector": {
            "buckets_path": {
              "docCount": "_count"
            },
            "script": "params.docCount >= 7"
          }
        }
      }
    },
    "7-*_Total_Sales": {
      "sum_bucket": {
        "buckets_path": "7-*>Total_Sale"
      }
    },
    "7_*_Total_Docs": {
      "sum_bucket": {
        "buckets_path": "7-*>_count"
      }
    }
  }
}

您将得到一个如下所示的答案，其中包含了您在xyz_Total_Sales和xyz_Total_Docs结果中所寻找的确切数字：

  "aggregations": {
    "*-3": {
      "doc_count_error_upper_bound": 0,
      "sum_other_doc_count": 0,
      "buckets": [
        {
          "key": "wolves",
          "doc_count": 2,
          "Total_Sale": {
            "value": 555
          }
        }
      ]
    },
    "7-*": {
      "doc_count_error_upper_bound": 0,
      "sum_other_doc_count": 0,
      "buckets": [
        {
          "key": "cats",
          "doc_count": 8,
          "Total_Sale": {
            "value": 9999
          }
        }
      ]
    },
    "4-6": {
      "doc_count_error_upper_bound": 0,
      "sum_other_doc_count": 0,
      "buckets": [
        {
          "key": "tigers",
          "doc_count": 6,
          "Total_Sale": {
            "value": 8888
          }
        },
        {
          "key": "lions",
          "doc_count": 5,
          "Total_Sale": {
            "value": 444
          }
        }
      ]
    },
    "*-3_Total_Sales": {
      "value": 555
    },
    "*-3_Total_Docs": {
      "value": 2
    },
    "4-6_Total_Sales": {
      "value": 9332
    },
    "4-6_Total_Docs": {
      "value": 11
    },
    "7-*_Total_Sales": {
      "value": 9999
    },
    "7_*_Total_Docs": {
      "value": 8
    }
  }