标签：elastic pre div com cti class lan term ast
参考资料：
https://elasticsearch.cn/book/elasticsearch_definitive_guide_2.x/_combining_the_two.html
特定概念：
桶（Buckets）满足特定条件的文档的集合
指标（Metrics）对桶内的文档进行统计计算
SELECT COUNT(color)
FROM table
GROUP BY color
COUNT(color) 相当于指标。
GROUP BY color 相当于桶。
聚合例子：
curl -XGET ‘localhost:9200/text/_search?pretty‘ -d ‘ {"size":0, "aggs": {"popular_ports": {"terms": {"field":"port"} } } }‘
对port字段做聚合，结果名称为popular_ports。size设为0表示不关心搜索结果，结果的hits部分会是空值。
计算每种颜色车辆价格的平均值
GET /cars/transactions/_search { "size" : 0, "aggs": { "colors": { "terms": { "field": "color" }, "aggs": { "avg_price": { "avg": { "field": "price" } } } } } }
嵌套桶
每个颜色的汽车制造商的分布
GET /cars/transactions/_search { "size" : 0, "aggs": { "colors": { "terms": { "field": "color" }, "aggs": { "avg_price": { "avg": { "field": "price" } }, "make": { "terms": { "field": "make" } } } } } }
每个颜色的汽车制造商的分布，以及各个制造商生产汽车的最高和最低价格。
GET /cars/transactions/_search { "size" : 0, "aggs": { "colors": { "terms": { "field": "color" }, "aggs": { "avg_price": { "avg": { "field": "price" } }, "make" : { "terms" : { "field" : "make" }, "aggs" : { "min_price" : { "min": { "field": "price"} }, "max_price" : { "max": { "field": "price"} } } } } } } }
标签：elastic pre div com cti class lan term ast
原文地址：http://www.cnblogs.com/dplearning/p/7010472.html
