Elastic Search中嵌套字段的术语聚合

Question

我在elasticsearch（YML中的定义）中具有字段的下一个映射：

              my_analyzer:
                  type: custom
                  tokenizer:  keyword
                  filter: lowercase

               products_filter:
                    type: "nested"
                    properties:
                        filter_name: {"type" : "string", analyzer: "my_analyzer"}
                        filter_value: {"type" : "string" , analyzer: "my_analyzer"}

每个文档都有很多过滤器，看起来像：

"products_filter": [
{
"filter_name": "Rahmengröße",
"filter_value": "33,5 cm"
}
,
{
"filter_name": "color",
"filter_value": "gelb"
}
,
{
"filter_name": "Rahmengröße",
"filter_value": "39,5 cm"
}
,
{
"filter_name": "Rahmengröße",
"filter_value": "45,5 cm"
}]

我试图获取唯一过滤器名称的列表以及每个过滤器的唯一过滤器值的列表。

我的意思是，我想获得结构是怎样的：Rahmengröße：
39.5厘米
45.5厘米
33.5厘米
颜色：
盖尔布

为了得到它，我尝试了几种聚合的变体，例如：

{
  "aggs": {
    "bla": {
      "terms": {
        "field": "products_filter.filter_name"
      },
      "aggs": {
        "bla2": {
          "terms": {
            "field": "products_filter.filter_value"
          }
        }
      }
    }
  }
}

这个请求是错误的。

它将为我返回唯一过滤器名称的列表，并且每个列表将包含所有filter_values的列表。

"bla": {
"doc_count_error_upper_bound": 0,
"sum_other_doc_count": 103,
"buckets": [
{
"key": "color",
"doc_count": 9,
"bla2": {
"doc_count_error_upper_bound": 4,
"sum_other_doc_count": 366,
"buckets": [
{
"key": "100",
"doc_count": 5
}
,
{
"key": "cm",
"doc_count": 5
}
,
{
"key": "unisex",
"doc_count": 5
}
,
{
"key": "11",
"doc_count": 4
}
,
{
"key": "160",
"doc_count": 4
}
,
{
"key": "22",
"doc_count": 4
}
,
{
"key": "a",
"doc_count": 4
}
,
{
"key": "alu",
"doc_count": 4
}
,
{
"key": "aluminium",
"doc_count": 4
}
,
{
"key": "aus",
"doc_count": 4
}
]
}
}
,

另外，我尝试使用反向嵌套聚合，但这对我没有帮助。

所以我认为我的尝试有逻辑上的错误吗？

Answer 1

如我所说。您的问题是您的文本被分析，elasticsearch总是在令牌级别聚合。因此，为了解决该问题，必须将字段值索引为单个标记。有两种选择：

• 不分析它们
• 使用关键字分析器+小写（不区分大小写的aggs）为它们编制索引

因此，将使用小写过滤器并删除重音符号（ö => o以及ß => ss您的字段的其他字段，以创建自定义关键字分析器）来进行设置，以便将它们用于聚合（raw和keyword）：

PUT /test
{
  "settings": {
    "analysis": {
      "analyzer": {
        "my_analyzer_keyword": {
          "type": "custom",
          "tokenizer": "keyword",
          "filter": [
            "asciifolding",
            "lowercase"
          ]
        }
      }
    }
  },
  "mappings": {
    "data": {
      "properties": {
        "products_filter": {
          "type": "nested",
          "properties": {
            "filter_name": {
              "type": "string",
              "analyzer": "standard",
              "fields": {
                "raw": {
                  "type": "string",
                  "index": "not_analyzed"
                },
                "keyword": {
                  "type": "string",
                  "analyzer": "my_analyzer_keyword"
                }
              }
            },
            "filter_value": {
              "type": "string",
              "analyzer": "standard",
              "fields": {
                "raw": {
                  "type": "string",
                  "index": "not_analyzed"
                },
                "keyword": {
                  "type": "string",
                  "analyzer": "my_analyzer_keyword"
                }
              }
            }
          }
        }
      }
    }
  }
}

测试文件，您给了我们：

PUT /test/data/1
{
  "products_filter": [
    {
      "filter_name": "Rahmengröße",
      "filter_value": "33,5 cm"
    },
    {
      "filter_name": "color",
      "filter_value": "gelb"
    },
    {
      "filter_name": "Rahmengröße",
      "filter_value": "39,5 cm"
    },
    {
      "filter_name": "Rahmengröße",
      "filter_value": "45,5 cm"
    }
  ]
}

这将是查询以使用raw字段进行汇总：

GET /test/_search
{
  "size": 0,
  "aggs": {
    "Nesting": {
      "nested": {
        "path": "products_filter"
      },
      "aggs": {
        "raw_names": {
          "terms": {
            "field": "products_filter.filter_name.raw",
            "size": 0
          },
          "aggs": {
            "raw_values": {
              "terms": {
                "field": "products_filter.filter_value.raw",
                "size": 0
              }
            }
          }
        }
      }
    }
  }
}

它确实带来了预期的结果（带有过滤器名称的存储桶和带有其值的子存储桶）：

{
  "took": 1,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "failed": 0
  },
  "hits": {
    "total": 1,
    "max_score": 0,
    "hits": []
  },
  "aggregations": {
    "Nesting": {
      "doc_count": 4,
      "raw_names": {
        "doc_count_error_upper_bound": 0,
        "sum_other_doc_count": 0,
        "buckets": [
          {
            "key": "Rahmengröße",
            "doc_count": 3,
            "raw_values": {
              "doc_count_error_upper_bound": 0,
              "sum_other_doc_count": 0,
              "buckets": [
                {
                  "key": "33,5 cm",
                  "doc_count": 1
                },
                {
                  "key": "39,5 cm",
                  "doc_count": 1
                },
                {
                  "key": "45,5 cm",
                  "doc_count": 1
                }
              ]
            }
          },
          {
            "key": "color",
            "doc_count": 1,
            "raw_values": {
              "doc_count_error_upper_bound": 0,
              "sum_other_doc_count": 0,
              "buckets": [
                {
                  "key": "gelb",
                  "doc_count": 1
                }
              ]
            }
          }
        ]
      }
    }
  }
}

另外，您可以将field与关键字分析器（以及一些规范化）结合使用，以获得更通用且不区分大小写的结果：

GET /test/_search
{
  "size": 0,
  "aggs": {
    "Nesting": {
      "nested": {
        "path": "products_filter"
      },
      "aggs": {
        "keyword_names": {
          "terms": {
            "field": "products_filter.filter_name.keyword",
            "size": 0
          },
          "aggs": {
            "keyword_values": {
              "terms": {
                "field": "products_filter.filter_value.keyword",
                "size": 0
              }
            }
          }
        }
      }
    }
  }
}

结果就是：

{
  "took": 1,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "failed": 0
  },
  "hits": {
    "total": 1,
    "max_score": 0,
    "hits": []
  },
  "aggregations": {
    "Nesting": {
      "doc_count": 4,
      "keyword_names": {
        "doc_count_error_upper_bound": 0,
        "sum_other_doc_count": 0,
        "buckets": [
          {
            "key": "rahmengrosse",
            "doc_count": 3,
            "keyword_values": {
              "doc_count_error_upper_bound": 0,
              "sum_other_doc_count": 0,
              "buckets": [
                {
                  "key": "33,5 cm",
                  "doc_count": 1
                },
                {
                  "key": "39,5 cm",
                  "doc_count": 1
                },
                {
                  "key": "45,5 cm",
                  "doc_count": 1
                }
              ]
            }
          },
          {
            "key": "color",
            "doc_count": 1,
            "keyword_values": {
              "doc_count_error_upper_bound": 0,
              "sum_other_doc_count": 0,
              "buckets": [
                {
                  "key": "gelb",
                  "doc_count": 1
                }
              ]
            }
          }
        ]
      }
    }
  }
}