elasticsearch - 具有脚本的ElasticSearch 6.6.0聚合平均无法正常工作

Question

我尝试在群集上运行以下内容:

GET _search
{
  "aggs": {
    "buckets": {
      "terms": {
        "field": "main_feature_id.keyword",
        "size": 10
      },
      "aggs": {
        "average_dwell": {
          "avg": {
            "field": "dwell.dwell_ms",
            "script": {
              "lang": "painless",
              "source": "long x = Math.round(_value*100)/100000; return x;"
            }
          }
        }
      }
    }
  }
}

但是，无论我尝试什么，我都无法使结果变得圆满。

结果如下所示:

"doc_count" : 26032,
      "average_dwell" : {
        "value" : 44.87277178006528
      }

有人可以告诉我我做错了什么吗，我敢肯定这很明显。

谢谢!

Answer 1

_value脚本将脚本应用于文档的每个值，然后计算修改后值的平均值。您似乎要实现的是将精度降低到两位小数。这可以通过使用bucket script aggregation获得期望值来实现。

{
  "aggs": {
    "buckets": {
      "terms": {
        "field": "main_feature_id.keyword",
        "size": 10
      },
      "aggs": {
        "average_dwell": {
          "avg": {
            "field": "dwell.dwell_ms"
          }
        },
        "rounded_avg": {
          "bucket_script": {
            "buckets_path": {
              "curr_avg": "average_dwell"
            },
            "script": "Math.round(params.curr_avg * 100)/100.0;"
          }
        }
      }
    }
  }
}