如何在ElasticSearch中汇总返回结果的数量？

Question

FYI, I'm using ES 1.7.2 in a Mac.

I've been trying to get the aggregations on a result set but what I'm getting is the aggregations on all the records.

Let's say I want to return 200 vehicles that are Ford Focus SE and from those 200, I want to know the Trims of all them and how many vehicles each Trim has. So basically a count for those Trims but also get the 200 results back.

Here's what I have so far(I'm using Sense/Marvel...Easier to test):

GET jdbc/_search
{
  "size": 200, 
  "query": {
    "filtered": {
      "filter": {
        "bool": {
          "must": [
            { "term": { "listing.model": "Focus"   }},
            { "term": { "listing.make": "Ford" }}
          ]
        }
      }
    }
  },
  "aggs": {
    "trims": {
      "terms": { "field": "listing.trim" }
    },
    "trim_SE": {
      "filter": {
        "term": { "listing.trim": "SE" }
      },
    "aggs": {
      "trims": {
        "terms": { "field": "listing.trim"}
        }
      }
    }
  },
  "post_filter": { 
    "term": { "listing.trim": "SE" }
  }
}

So I do get 20 results back like so:

{
   "took": 18,
   "timed_out": false,
   "_shards": {
      "total": 5,
      "successful": 5,
      "failed": 0
   },
   "hits": {
      "total": 10338,
      "max_score": 1,
      "hits": [
         {
            "_index": "myindex",
            "_type": "mytype",
            "_id": "472",
            "_score": 1,
            "_source": {
               "listing": {
                  "vin": "111111111111",
                  "year": 2013,
                  "make": "Ford",
                  "model": "Focus",
                  "trim": "SE",
               }
            }
         },
         {...}
      ]
   }
   "aggregations": {
      "trims": {
         "doc_count_error_upper_bound": 0,
         "sum_other_doc_count": 30,
         "buckets": [
            {
               "key": "SE",
               "doc_count": 10338
            },
            {
               "key": "SEL",
               "doc_count": 1000
                },
            {
               "key": "Titanium",
               "doc_count": 874
            },
            {
               "key": "SES",
               "doc_count": 585
            },
            {
               "key": "S",
               "doc_count": 554
            },
            {
               "key": "",
               "doc_count": 447
            },
            {
               "key": "ST",
               "doc_count": 339
            },
            {
               "key": "ZTS",
               "doc_count": 60
            },
            {
               "key": "LX",
               "doc_count": 56
            },
            {
               "key": "Electric",
               "doc_count": 18
            }
         ]
      },
      "trim_SE": {
         "doc_count": 10338,
         "trims": {
            "doc_count_error_upper_bound": 0,
            "sum_other_doc_count": 0,
            "buckets": [
               {
                  "key": "SE",
                  "doc_count": 10338
               }
            ]
         }
      }
   }
}

But as you can see, the Trims show up with a bigger count than the 200, which means it's doing the aggregations on all the vehicles.

I need some help and I can't find anything that actually makes this work.

Thanks for the help in advance!

Answer 1

You should add the same filter from the query to the aggregation. Note that I've only created the example for the facet "trims":

{
    "aggs": {
        "trims": {
            "filter": {
                "bool": {
                    "must": [
                        {
                            "term": {
                                "listing.model": "Focus"
                            }
                        },
                        {
                            "term": {
                                "listing.make": "Ford"
                            }
                        }
                    ]
                }
            },
            "aggs": {
                "trims": {
                    "terms": {
                        "field": "listing.trim"
                    }
                }
            }
        }
    }
}

I'm not sure to have understood your usage of the post_filter, but if needed you can just add it in the "filter" section of the aggregation.

Source: https://www.elastic.co/guide/en/elasticsearch/reference/current/search-aggregations-bucket-filter-aggregation.html