[FIXED] How to aggregate on size of nested document in ElasticSearch?

Issue

Nested field name is transactions.

Each document has a list of transactions.

I wish to aggregate on the number of transactions. Information i seek is the number Nf documents with more than one transaction.

I tried the following :

  "aggs": {
    "tx_count": {
      "terms": {
        "script": {
          "inline": "if(doc['transactions'].size>1){return 1;} else {return 0;}"
        }
      }
    }
  }

I also tried using this aggregation within a nested aggregation. Is there a way to do this?

I'm on ES version 5.6 currently.

Solution

You can use params._source to calculate the transactions length:

{
  "size": 0,
  "aggs": {
    "tx_count": {
      "terms": {
        "script": {
          "inline": "if (params._source['transactions'].size() > 1) { return 1; } else { return 0; }"
        }
      }
    }
  }
}

BTW notice that it's .size(), not .size.

Answered By - Joe - ElasticsearchBook.com

Answer Checked By - Robin (PHPFixing Admin)