SQL场景：Metrics查询
SELECT avg(privce) FROM table where price >= 10000 and price <= 35000 GROUP BY color
查询在一定价格区间的，按颜色分组的平均值
Aggregation API:
在API实现上是先做过滤再聚合，分桶后加入Metrics聚合：
GET /cars/transactions/_search
{
"size" : 0,
"query": {
"range" : {
"price" : {
"gte" : 10000,
"lt" : 35000
}
}
},
"aggs" : {
"popular_colors" : {
"terms" : {
"field" : "color"
},
"aggs": {
"price_avg": {
"avg": {
"field": "price"
}
}
}
}
}
}
结果：
image.png
java API：
def aggTest3(): Unit = {
import scala.collection.JavaConverters._
val rangeQuery = QueryBuilders.rangeQuery("price").gte(10000).lt(35000)
val agg = AggregationBuilders
.terms("color")
.field("color")
.order(Terms.Order.count(false))
val avg = AggregationBuilders
.avg("price")// also sum / max
.field("price")
agg.subAggregation(avg)
val searchRes = queryBuilder
.setQuery(rangeQuery)
.addAggregation(agg)
.execute()
.actionGet()
searchRes.getAggregations.get("color").asInstanceOf[Terms].getBuckets.asScala.foreach{ bucket =>
println(s"key: ${bucket.getKeyAsString}, value ${bucket.getDocCount}")
bucket.getAggregations.getAsMap.asScala.foreach{ agg =>
println(s"key: ${agg._1}, value ${agg._2.asInstanceOf[InternalAvg].getValue}")
}
println(s"----------------------------------------")
}
}
结果：
image.png
