Learning Elasticsearch

Query structure

The aggregation query is executed using the search API. You can add a query to restrict the document you want to run the aggregations on. Let's start by looking at a simple aggregation to group all the products by their category. In the SQL world, the query would look like the following:

select count(*) from Productgroup by category; 

In Elasticsearch, to achieve the same, we would do the following:

POST chapter8/_search{ "aggs" :{   "category_products" : {     "terms" : {       "field" : "category"      }    }  }}

The basic structure is as follows:

 "aggs" :{   // Can be aggs or aggregation.   "category_products" : { // Name of the aggregation     "terms" : {  // Type of the aggregation

The results of the preceding query are as follows:

{.... "aggregations": ...