The Geovisualization REST API provides a mechanism that allows you to retrieve statistics about column values from the results of your query. For example, to determine the minimum, maximum and average values of certain columns to determine how to distribute the colors in a heat map and change your code accordingly.

To fetch statistical data, you construct a stats JSON object that you send in the request body to the Geovisualization REST API, along with the query ID. The stats object represents a nested list containing column names and dynamic parameters:

• column_stats: This object contains column names, each of which is a facet or metric defined in the query, followed by a list of statistical functions ($min, $max, $count_distinct, $count, $average or $sum) to be run on them. (See Query Statistics.)
• dynamic: This object contains dynamic parameters, each of which is defined in the query, or $drop to remove that parameter from the filters. (See Using Dynamic Parameters.)

A complete stats JSON object would be structured as follows:

{
  "stats": [{
    "column_stats": {
      <column_name>: [<stats_function>, <stats_function>],
      <column_name>: [<stats_function>, <stats_function>]
    },
    "dynamic": {
      <dynamic_parameter>: <value> OR "$drop",
      <dynamic_parameter>: <value> OR "$drop",
    }
  }]
}

To get the statistics, include the object above as the request body in an authenticated POST to the following resource:

https://datalens.api.here.com/v1/queries/{QUERY_ID}/stats?app_code={YOUR_APP_CODE}&app_id={YOUR_APP_ID}

You can also use the queries/_ID_ endpoint in the 07. Query CRUD folder of our Postman collection.

You will receive a response body that includes a list of values representing the statistical data for the query.

https://datalens.api.here.com/v1/queries/{QUERY_ID}/stats?app_code={YOUR_APP_CODE}&app_id={YOUR_APP_ID}

{

  "stats": [{
    "column_stats": {"Magnitude": ["$min","$max"]},
    "dynamic": {"min":"$drop", "max":"$drop"}}
]}