elasticsearc使用指南之ES管道聚合(Pipeline Aggregation)

GET /_search
{
  "size": 0,
  "aggs": {
    "min_monthly_sales": {
      "date_histogram": {
        "field": "date",
        "calendar_interval": "month"
      },
      "aggs": {
        "sales_pipeline": {
          "avg_bucket": {
            "buckets_path": "min_sales_per_month>_count"
          }
        },
        "min_sales_per_month": {
          "min_bucket": {
            "buckets_path": "sales_per_day"
          }
        },
        "sales_per_day": {
          "date_histogram": {
            "field": "date",
            "calendar_interval": "day"
          },
          "aggs": {
            "sales": {
              "sum": {
                "field": "sales"
              }
            }
          }
        }
      }
    }
  }
}