9.ElasticSearch聚合查询

分组语法

按照name分组统计

{
  "size": 0,
  "query":{
      "match_all":{
      }
  },
  "aggs": {
    "nameGroup": {
      "terms": {
        "field": "name"
      }
    }
  }
}

返回结果

"aggregations": { - 
    "nameGroup": { - 
      "doc_count_error_upper_bound": 0,
      "sum_other_doc_count": 0,
      "buckets": [ - 
        { - 
          "key": "lisi",
          "doc_count": 1
        },
        { - 
          "key": "zhangsan",
          "doc_count": 1
        }
      ]
    }
  }

执行后把name字段分组展示，doc_count是组对应的数量

函数统计

平均值

{
  "size": 0,
  "query": {
    "match_all": {}
  },
  "aggs": {
    "ageAvg": {
      "avg": {
        "field": "age"
      }
    }
  }
}

求和

{
  "size": 0,
  "query": {
    "match_all": {}
  },
  "aggs": {
    "ageSum": {
      "sum": {
        "field": "age"
      }
    }
  }
}

最大值

{
  "size": 0,
  "query": {
    "match_all": {}
  },
  "aggs": {
    "ageMax": {
      "max": {
        "field": "age"
      }
    }
  }
}

最小值

{
  "size": 0,
  "query": {
    "match_all": {}
  },
  "aggs": {
    "ageMin": {
      "min": {
        "field": "age"
      }
    }
  }
}