白话Elasticsearch32-深入聚合数据分析之案例实战Terms Aggs 统计哪种颜色电视销量最高

概述

继续跟中华石杉老师学习ES，第32篇

课程地址： https://www.roncoo.com/view/55

Terms Aggregation官方文档

官方文档：戳这里

详细说明，参考官网即可，下面我们用示例来演示下

案例一：统计哪种颜色电视销量最高

模拟数据

创建索引

代码语言：javascript复制

PUT /tvs
{
  "mappings": {
    "sales": {
      "properties": {
        "price": {
          "type": "long"
        },
        "color": {
          "type": "keyword"
        },
        "brand": {
          "type": "keyword"
        },
        "sold_date": {
          "type": "date"
        }
      }
    }
  }
}

模拟一批数据

代码语言：javascript复制

POST /tvs/sales/_bulk
{ "index": {}}
{ "price" : 1000, "color" : "红色", "brand" : "长虹", "sold_date" : "2016-10-28" }
{ "index": {}}
{ "price" : 2000, "color" : "红色", "brand" : "长虹", "sold_date" : "2016-11-05" }
{ "index": {}}
{ "price" : 3000, "color" : "绿色", "brand" : "小米", "sold_date" : "2016-05-18" }
{ "index": {}}
{ "price" : 1500, "color" : "蓝色", "brand" : "TCL", "sold_date" : "2016-07-02" }
{ "index": {}}
{ "price" : 1200, "color" : "绿色", "brand" : "TCL", "sold_date" : "2016-08-19" }
{ "index": {}}
{ "price" : 2000, "color" : "红色", "brand" : "长虹", "sold_date" : "2016-11-05" }
{ "index": {}}
{ "price" : 8000, "color" : "红色", "brand" : "三星", "sold_date" : "2017-01-01" }
{ "index": {}}
{ "price" : 2500, "color" : "蓝色", "brand" : "小米", "sold_date" : "2017-02-12" }

原始数据：

统计哪种颜色的电视销量最高

DSL

代码语言：javascript复制

GET /tvs/sales/_search
{
  "size": 0,
  "aggs": {
    "popular_colors": {
      "terms": {
        "field": "color"
      }
    }
  }
}

解读：

size：只获取聚合结果，而不要执行聚合的原始数据
aggs：固定语法，要对一份数据执行分组聚合操作
popular_colors：就是对每个aggs，都要起一个名字，自定义，叫啥都行
terms：根据字段的值进行分组
field：根据指定的字段的值进行分组

类比官方介绍

返回结果：

hits.hits：我们指定了size是0，所以hits.hits就是空的，否则会把执行聚合的那些原始数据给你返回回来
aggregations：聚合结果
popular_color：我们指定的某个聚合的名称
buckets：根据我们指定的field划分出的buckets
key：每个bucket对应的那个值
doc_count：这个bucket分组内，有多少个数据

类比官网说明

每种颜色对应的bucket中的数据的数量，其实就是这种颜色的销量

默认的排序规则：按照doc_count降序排序

size 参数示例

外层size

当我们外层不加size的时候，会返回执行聚合的那些原始数据

代码语言：javascript复制

GET /tvs/sales/_search
{
  "aggs": {
    "popular_color": {
      "terms": {
        "field": "color"
      }
    }
  }
}

代码语言：javascript复制

{
  "took": 2,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "skipped": 0,
    "failed": 0
  },
  "hits": {
    "total": 8,
    "max_score": 1,
    "hits": [
      {
        "_index": "tvs",
        "_type": "sales",
        "_id": "QzGrtGwBCp8vhw_gCmb9",
        "_score": 1,
        "_source": {
          "price": 2000,
          "color": "红色",
          "brand": "长虹",
          "sold_date": "2016-11-05"
        }
      },
      {
        "_index": "tvs",
        "_type": "sales",
        "_id": "PzGrtGwBCp8vhw_gCmb9",
        "_score": 1,
        "_source": {
          "price": 2000,
          "color": "红色",
          "brand": "长虹",
          "sold_date": "2016-11-05"
        }
      },
      {
        "_index": "tvs",
        "_type": "sales",
        "_id": "QDGrtGwBCp8vhw_gCmb9",
        "_score": 1,
        "_source": {
          "price": 3000,
          "color": "绿色",
          "brand": "小米",
          "sold_date": "2016-05-18"
        }
      },
      {
        "_index": "tvs",
        "_type": "sales",
        "_id": "QjGrtGwBCp8vhw_gCmb9",
        "_score": 1,
        "_source": {
          "price": 1200,
          "color": "绿色",
          "brand": "TCL",
          "sold_date": "2016-08-19"
        }
      },
      {
        "_index": "tvs",
        "_type": "sales",
        "_id": "RDGrtGwBCp8vhw_gCmb9",
        "_score": 1,
        "_source": {
          "price": 8000,
          "color": "红色",
          "brand": "三星",
          "sold_date": "2017-01-01"
        }
      },
      {
        "_index": "tvs",
        "_type": "sales",
        "_id": "PjGrtGwBCp8vhw_gCmb9",
        "_score": 1,
        "_source": {
          "price": 1000,
          "color": "红色",
          "brand": "长虹",
          "sold_date": "2016-10-28"
        }
      },
      {
        "_index": "tvs",
        "_type": "sales",
        "_id": "QTGrtGwBCp8vhw_gCmb9",
        "_score": 1,
        "_source": {
          "price": 1500,
          "color": "蓝色",
          "brand": "TCL",
          "sold_date": "2016-07-02"
        }
      },
      {
        "_index": "tvs",
        "_type": "sales",
        "_id": "RTGrtGwBCp8vhw_gCmb9",
        "_score": 1,
        "_source": {
          "price": 2500,
          "color": "蓝色",
          "brand": "小米",
          "sold_date": "2017-02-12"
        }
      }
    ]
  },
  "aggregations": {
    "popular_color": {
      "doc_count_error_upper_bound": 0,
      "sum_other_doc_count": 0,
      "buckets": [
        {
          "key": "红色",
          "doc_count": 4
        },
        {
          "key": "绿色",
          "doc_count": 2
        },
        {
          "key": "蓝色",
          "doc_count": 2
        }
      ]
    }
  }
}

当把外层的 size设置为1 ，返回1条执行聚合的那些原始数据