一、基础知识

有2种方式过滤查询结果

• 用带filter语句的boolean查询
  对搜索结果和聚合同时生效
• 使用post-filter
  只对搜索结果生效，不对聚合生效

查询使用文档数据在文章末尾

二、查询演示

• 2.1 boolean filter search
  参数

{
  "query": {
    "bool": {
      "filter": [
        {
          "term": {
            "color": "red"
          }
        },
        {
          "term": {
            "brand": "dior"
          }
        }
      ]
    }
  },
  "aggs": {
    "models": {
      "terms": {
        "field": "model"
      }
    }
  }
}

响应（hits和聚合中的文档数量一致）

{
    "took": 2,
    "timed_out": false,
    "_shards": {
        "total": 1,
        "successful": 1,
        "skipped": 0,
        "failed": 0
    },
    "hits": {
        "total": {
            "value": 3,
            "relation": "eq"
        },
        "max_score": 0,
        "hits": [
            {
                "_index": "shirt",
                "_id": "2",
                "_score": 0,
                "_source": {
                    "brand": "dior",
                    "color": "red",
                    "model": "cillum"
                }
            },
            {
                "_index": "shirt",
                "_id": "5",
                "_score": 0,
                "_source": {
                    "brand": "dior",
                    "color": "red",
                    "model": "Jimmy"
                }
            },
            {
                "_index": "shirt",
                "_id": "6",
                "_score": 0,
                "_source": {
                    "brand": "dior",
                    "color": "red",
                    "model": "Toom"
                }
            }
        ]
    },
    "aggregations": {
        "models": {
            "doc_count_error_upper_bound": 0,
            "sum_other_doc_count": 0,
            "buckets": [
                {
                    "key": "Jimmy",
                    "doc_count": 1
                },
                {
                    "key": "Toom",
                    "doc_count": 1
                },
                {
                    "key": "cillum",
                    "doc_count": 1
                }
            ]
        }
    }
}

• 2.2 post_filter search
  参数

{
  "query": {
    "bool": {
      "filter": {
        "term": { "brand": "dior" } 
      }
    }
  },
  "aggs": {
    "colors": {
      "terms": { "field": "color" } 
    }
  },
  "post_filter": { 
    "term": { "color": "red" }
  }
}

响应(聚合中显示有4个文档，hits被过滤掉了一个)

{
    "took": 2,
    "timed_out": false,
    "_shards": {
        "total": 1,
        "successful": 1,
        "skipped": 0,
        "failed": 0
    },
    "hits": {
        "total": {
            "value": 3,
            "relation": "eq"
        },
        "max_score": 0,
        "hits": [
            {
                "_index": "shirt",
                "_id": "2",
                "_score": 0,
                "_source": {
                    "brand": "dior",
                    "color": "red",
                    "model": "cillum"
                }
            },
            {
                "_index": "shirt",
                "_id": "5",
                "_score": 0,
                "_source": {
                    "brand": "dior",
                    "color": "red",
                    "model": "Jimmy"
                }
            },
            {
                "_index": "shirt",
                "_id": "6",
                "_score": 0,
                "_source": {
                    "brand": "dior",
                    "color": "red",
                    "model": "Toom"
                }
            }
        ]
    },
    "aggregations": {
        "colors": {
            "doc_count_error_upper_bound": 0,
            "sum_other_doc_count": 0,
            "buckets": [
                {
                    "key": "red",
                    "doc_count": 3
                },
                {
                    "key": "greed",
                    "doc_count": 1
                }
            ]
        }
    }
}

三、测试数据

{
    "took": 1,
    "timed_out": false,
    "_shards": {
        "total": 1,
        "successful": 1,
        "skipped": 0,
        "failed": 0
    },
    "hits": {
        "total": {
            "value": 6,
            "relation": "eq"
        },
        "max_score": 1,
        "hits": [
            {
                "_index": "shirt",
                "_id": "2",
                "_score": 1,
                "_source": {
                    "brand": "dior",
                    "color": "red",
                    "model": "cillum"
                }
            },
            {
                "_index": "shirt",
                "_id": "3",
                "_score": 1,
                "_source": {
                    "brand": "gucci",
                    "color": "yellow",
                    "model": "Excepteur ullamco"
                }
            },
            {
                "_index": "shirt",
                "_id": "4",
                "_score": 1,
                "_source": {
                    "brand": "gucci",
                    "color": "gray",
                    "model": "ut sit ad dolore magna"
                }
            },
            {
                "_index": "shirt",
                "_id": "1",
                "_score": 1,
                "_source": {
                    "brand": "dior",
                    "color": "greed",
                    "model": "culpa qui do non"
                }
            },
            {
                "_index": "shirt",
                "_id": "5",
                "_score": 1,
                "_source": {
                    "brand": "dior",
                    "color": "red",
                    "model": "Jimmy"
                }
            },
            {
                "_index": "shirt",
                "_id": "6",
                "_score": 1,
                "_source": {
                    "brand": "dior",
                    "color": "red",
                    "model": "Toom"
                }
            }
        ]
    }
}