java - Elasticsearch 按字段聚合和求和(group by)

Question

我的索引中有下一个数据:

{
  "category": "fruit",
  "name": "apple",
  "price": 2.6,
},
{
  "category": "fruit",
  "name": "orange",
  "price": 1.8,
},
{
  "category": "vegs",
  "name": "tomato",
  "price": 0.95,
}

我想按类别对价格进行求和，得到如下结果:

fruit - 4.4
vegs - 0.95

我确实意识到我需要使用嵌套聚合，但我不知 Prop 体如何使用。这是我到目前为止得到的代码:

    SearchRequest searchRequest = new SearchRequest("products");
    SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();

    searchSourceBuilder.
            aggregation(AggregationBuilders.
                    nested("category_price", "products").
                    subAggregation(
                            AggregationBuilders
                                    .terms("field").field("category")).
                    subAggregation(
                            AggregationBuilders.avg("avg_price").field("price"))
            );

    searchRequest.source(searchSourceBuilder);

    SearchResponse response = client.search(searchRequest);
    Nested agg = response.getAggregations().get("category_price");

    Terms name = agg.getAggregations().get("field");
    for (Terms.Bucket bucket : name.getBuckets()) {
        ReverseNested resellerToProduct = bucket.getAggregations().get("avg_price");
        System.out.println(resellerToProduct.getDocCount());
        System.out.println(resellerToProduct.getName());
    }

Answer 1

您创建了第二个聚合作为同级聚合，您只需要子聚合。 +你不必在这里使用嵌套聚合。

AggregationBuilder aggregationBuilder = AggregationBuilders.global("agg")
    .subAggregation(AggregationBuilders.terms("by_category").field("category")
    .subAggregation(AggregationBuilders.sum("sum_price").field("price")));