# How to get array size for each document

**URL:** <https://discuss.elastic.co/t/how-to-get-array-size-for-each-document/226599>\
**Category:** Elasticsearch\
**Created:** [April 5, 2020, 10:42pm UTC](https://discuss.elastic.co/t/how-to-get-array-size-for-each-document/226599 "2020-04-05T22:42:06Z")\
**Posts on this page:** 1\
**Showing post:** 2

<div class="post-metadata">

**Author:** ![Luca\_Belluccini](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/luca_belluccini/32/33239_2.png) [@Luca\_Belluccini](https://discuss.elastic.co/u/Luca_Belluccini)\
**Post date:** [April 5, 2020, 11:08pm UTC](https://discuss.elastic.co/t/how-to-get-array-size-for-each-document/226599/2 "2020-04-05T23:08:11Z")

</div>

Hello @ntsh999,

The "easiest" solution is using `scripted fields`, but it is gonna to be slow and consume resources, as you're accessing to the `_source`:

```auto
GET your_index_name/_search
{
  "script_fields": {
    "number_of_breaches": {
      "script": {
        "source": "params['_source'].breaches.length"
      }
    }
  },
  "_source": {
    "excludes": ["breaches"]
  }
}
# Response
{
  "took" : 672,
  "timed_out" : false,
  "_shards" : {
    "total" : 1,
    "successful" : 1,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : {
      "value" : 1,
      "relation" : "eq"
    },
    "max_score" : 1.0,
    "hits" : [
      {
        "_index" : "mytest",
        "_type" : "_doc",
        "_id" : "1",
        "_score" : 1.0,
        "_source" : {
          "contact" : 9899999999,
          "name" : "xyx",
          "age" : 45,
          "email" : ""
        },
        "fields" : {
          "number_of_breaches" : [
            1
          ]
        }
      }
    ]
  }
}

```

The best solution is usually to compute such fields at indexing time, for example using the Ingest Pipelines ([documentation](https://www.elastic.co/guide/en/elasticsearch/reference/current/ingest.html)):

```auto
PUT _ingest/pipeline/count_breaches
{
    "description": "Counts the breaches",
    "processors": [
      {
        "script": {
          "source": "ctx.number_of_breaches = ctx.containsKey('breaches') ? ctx.breaches.length : 0"
        }
      }
    ]
}

```

The pipeline can be used when indexing the document.

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