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Maximum aggregations

The max metric is a single-value metric that returns the maximum value of a field.

The max aggregation compares numeric fields using a double (double-precision) representation. Results should be considered approximate for fields containing long or unsigned_long integer values greater than 2⁵³ because the number of significant bits in a double mantissa is 53.

Parameters

The max aggregation takes the following parameters.

Example

This following example request finds the most expensive item—the item with the maximum value of the base_unit_price—in the OpenSearch Dashboards e-commerce sample data:

GET opensearch_dashboards_sample_data_ecommerce/_search
{
  "size": 0,
  "aggs": {
    "max_base_unit_price": {
      "max": {
        "field": "products.base_unit_price"
      }
    }
  }
}

Example response

As shown in the following example response, the aggregation returns the maximum value of products.base_unit_price:

{
  "took": 24,
  "timed_out": false,
  "_shards": {
    "total": 1,
    "successful": 1,
    "skipped": 0,
    "failed": 0
  },
  "hits": {
    "total": {
      "value": 4675,
      "relation": "eq"
    },
    "max_score": null,
    "hits": []
  },
  "aggregations": {
    "max_base_unit_price": {
      "value": 540
    }
  }
}

You can use the aggregation name (max_base_unit_price) as a key to retrieve the aggregation from the response.

Missing values

You can assign a value to missing instances of the aggregated field. See Missing aggregations for more information.

Missing values are normally ignored by max. If you use missing to assign a value greater than any existing value, max returns this replacement value as the maximum value.