sum聚合的两列相除排序问题

POST /_search

{

  "aggs": {

    "sales_per_month": {

      "date_histogram": {

        "field": "date",

        "calendar_interval": "month"

      },

      "aggs": {

        "sale_type": {

          "terms": {

            "field": "type"

          },

          "aggs": {

            "sales": {

              "sum": {

                "field": "price"

              }

            }

          }

        },

        "hat_vs_bag_ratio": {

          "bucket_script": {

            "buckets_path": {

              "hats": "sale_type['hat']>sales",   

              "bags": "sale_type['bag']>sales"    

            },

            "script": "params.hats / params.bags"

          }

        }

      }

    }

  }

}