Executing a stats aggregation
The most used metric aggregations are stats aggregations, which are able to compute several metrics of a bucket of documents in one go.
They are generally used as a terminal aggregation step to compute values that will be used directly or for further sorting.
Getting ready
You need an up and running Elasticsearch installation, as we described in the Downloading and installing Elasticsearch recipe in Chapter 1, Getting Started.
To execute these commands, any HTTP client can be used, such as curl (https://curl.haxx.se/), Postman (https://www.getpostman.com/), or similar. Using Kibana Console is recommended, as it provides code completion and better character escaping for Elasticsearch.
To correctly execute the following commands, you will need an index populated with the ch07/populate_aggregation.sh commands available in the online code.
The index that’s used in this recipe is index-agg.
How to do it...
To execute a stats aggregation...
