概述
继续跟中华石杉老师学习ES，第41篇
课程地址： https://www.roncoo.com/view/55
官方说明
Filter Aggregation：戳这里
案例
需求： 统计牌品最近一个月的平均价格
今天是 2019-08-24 ，为了演示该案例，我们批量更新下数据
POST /tvs/sales/_bulk {"update":{"_id":"3n0msmwBYSg4rD-7WPab"}} {"doc":{"sold_date":"2019-07-30"}} {"update":{"_id":"4H0msmwBYSg4rD-7WPab"}} {"doc":{"sold_date":"2019-01-05"}} {"update":{"_id":"4n0msmwBYSg4rD-7WPab"}} {"doc":{"sold_date":"2019-04-12"}} {"update":{"_id":"230msmwBYSg4rD-7WPaa"}} {"doc":{"sold_date":"2019-03-28"}} {"update":{"_id":"3X0msmwBYSg4rD-7WPab"}} {"doc":{"sold_date":"2019-05-20"}} {"update":{"_id":"3H0msmwBYSg4rD-7WPab"}} {"doc":{"sold_date":"2019-06-05"}} {"update":{"_id":"330msmwBYSg4rD-7WPab"}} {"doc":{"sold_date":"2019-08-02"}} {"update":{"_id":"4X0msmwBYSg4rD-7WPab"}} {"doc":{"sold_date":"2019-07-30"}}
更新后的数据：
DSL:
#统计牌品最近一个月的平均价格 GET /tvs/sales/_search { "query": { "term": { "brand": "TCL" } }, "aggs": { "recent_30d": { "filter": { "range": { "sold_date": { "gte": "now-30d" } } }, "aggs": { "recent_30d_price": { "avg": { "field": "price" } } } } }, "size": 0 }
返回
分析一下：
aggs.filter，针对的是聚合。
为什么不把filter放在query里呢？ 如果放query里面的filter，是全局的，会对所有的数据都有影响 。
但是假设你要统计TCL电视，最近1个月的平均值; 最近3个月的平均值; 最近6个月的平均值
那就需要对bucket 进行 filter：对不同的bucket下的aggs，进行filter
#统计牌品最近一个月的平均价格 GET /tvs/sales/_search { "query": { "term": { "brand": "TCL" } }, "aggs": { "recent_30d": { "filter": { "range": { "sold_date": { "gte": "now-30d" } } }, "aggs": { "recent_30d_price": { "avg": { "field": "price" } } } }, "recent_90d":{ "filter": { "range": { "sold_date": { "gte": "now-90d" } } }, "aggs": { "recent_90d_price": { "avg": { "field": "price" } } } }, "recent_180d":{ "filter": { "range": { "sold_date": { "gte": "now-180d" } } }, "aggs": { "recent_180d_price": { "avg": { "field": "price" } } } } } }
返回：
{ "took": 12, "timed_out": false, "_shards": { "total": 5, "successful": 5, "skipped": 0, "failed": 0 }, "hits": { "total": 2, "max_score": 0.9808292, "hits": [ { "_index": "tvs", "_type": "sales", "_id": "330msmwBYSg4rD-7WPab", "_score": 0.9808292, "_source": { "price": 1200, "color": "绿色", "brand": "TCL", "sold_date": "2019-08-02" } }, { "_index": "tvs", "_type": "sales", "_id": "3n0msmwBYSg4rD-7WPab", "_score": 0.6931472, "_source": { "price": 1500, "color": "蓝色", "brand": "TCL", "sold_date": "2019-07-30" } } ] }, "aggregations": { "recent_30d": { "doc_count": 2, "recent_30d_price": { "value": 1350 } }, "recent_90d": { "doc_count": 2, "recent_90d_price": { "value": 1350 } }, "recent_180d": { "doc_count": 2, "recent_180d_price": { "value": 1350 } } } }
