Cumulative Sum Aggregation

edit

This functionality is in technical preview and may be changed or removed in a future release. Elastic will work to fix any issues, but features in technical preview are not subject to the support SLA of official GA features.

A parent pipeline aggregation which calculates the cumulative sum of a specified metric in a parent histogram (or date_histogram) aggregation. The specified metric must be numeric and the enclosing histogram must have min_doc_count set to 0 (default for histogram aggregations).

Syntax

edit

A cumulative_sum aggregation looks like this in isolation:

{
    "cumulative_sum": {
        "buckets_path": "the_sum"
    }
}

Table 10. cumulative_sum Parameters

Parameter Name Description Required Default Value

buckets_path

The path to the buckets we wish to find the cumulative sum for (see buckets_path Syntax for more details)

Required

format

format to apply to the output value of this aggregation

Optional, defaults to null

The following snippet calculates the cumulative sum of the total monthly sales:

POST /sales/_search
{
    "size": 0,
    "aggs" : {
        "sales_per_month" : {
            "date_histogram" : {
                "field" : "date",
                "interval" : "month"
            },
            "aggs": {
                "sales": {
                    "sum": {
                        "field": "price"
                    }
                },
                "cumulative_sales": {
                    "cumulative_sum": {
                        "buckets_path": "sales" 
                    }
                }
            }
        }
    }
}

buckets_path instructs this cumulative sum aggregation to use the output of the sales aggregation for the cumulative sum

And the following may be the response:

{
   "took": 11,
   "timed_out": false,
   "_shards": ...,
   "hits": ...,
   "aggregations": {
      "sales_per_month": {
         "buckets": [
            {
               "key_as_string": "2015/01/01 00:00:00",
               "key": 1420070400000,
               "doc_count": 3,
               "sales": {
                  "value": 550.0
               },
               "cumulative_sales": {
                  "value": 550.0
               }
            },
            {
               "key_as_string": "2015/02/01 00:00:00",
               "key": 1422748800000,
               "doc_count": 2,
               "sales": {
                  "value": 60.0
               },
               "cumulative_sales": {
                  "value": 610.0
               }
            },
            {
               "key_as_string": "2015/03/01 00:00:00",
               "key": 1425168000000,
               "doc_count": 2,
               "sales": {
                  "value": 375.0
               },
               "cumulative_sales": {
                  "value": 985.0
               }
            }
         ]
      }
   }
}