41深入聚合数据分析

实际上来说，我们之前学习的搜索相关的知识，完全可以和聚合组合起来使用

对于sql分组，既有搜索又有分组

select count(*)
from tvs.sales
where brand like "%长%"
group by price

es aggregation有一个概念scope：任何的聚合，都必须在搜索出来的结果数据中进行，搜索结果，就是聚合分析操作的scope

搜索品牌是小米的电视，并根据颜色分组

GET /tvs/sales/_search 
{
  "size": 0,
  "query": {
    "term": {
      "brand": {
        "value": "小米"
      }
    }
  },
  "aggs": {
    "group_by_color": {
      "terms": {
        "field": "color"
      }
    }
  }
}

响应结果

{
  "took": 0,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "skipped": 0,
    "failed": 0
  },
  "hits": {
    "total": 2,
    "max_score": 0,
    "hits": []
  },
  "aggregations": {
    "group_by_color": {
      "doc_count_error_upper_bound": 0,
      "sum_other_doc_count": 0,
      "buckets": [
        {
          "key": "绿色",
          "doc_count": 1
        },
        {
          "key": "蓝色",
          "doc_count": 1
        }
      ]
    }
  }
}