# Sorted indices and early termination

**URL:** <https://discuss.elastic.co/t/sorted-indices-and-early-termination/191553>\
**Category:** Elasticsearch\
**Created:** [July 22, 2019, 1:14am UTC](https://discuss.elastic.co/t/sorted-indices-and-early-termination/191553 "2019-07-22T01:14:50Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![krish1](https://avatars.discourse-cdn.com/v4/letter/k/b5e925/32.png) [@krish1](https://discuss.elastic.co/u/krish1)\
**Post date:** [July 22, 2019, 1:14am UTC](https://discuss.elastic.co/t/sorted-indices-and-early-termination/191553/1 "2019-07-22T01:14:51Z")

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I have gone about reading this [documentation](https://www.elastic.co/guide/en/elasticsearch/reference/master/index-modules-index-sorting.html) and [blog](https://www.elastic.co/blog/index-sorting-elasticsearch-6-0) on index sorting and early termination and I have a couple of questions. I have an index with multiple fields(Simplified mappings below) most of which are text fields with a custom analyzer(additionally I use BM25 as my similarity algorithm) and I have a field called rank which is an integer what I would like to sort my index based on and terminate early. I perform a multi\_match query(simplified query below) based on these "text" fields, add a sort to the rank in the query, set "track\_total\_hits" : false and set "size": 1000(I want a total of 1000 docs returned)

Here's my question

1. Since my query is not a bool query, how does ElasticSearch(ES) know wether a particular document should be considered or not?
2. How many documents per shard will elastic search look at before terminating(1000 I guess but curious to know the answer here), also lets say I want it to look at a specific set number of documents per shard, can I use [terminate\_after](https://www.elastic.co/guide/en/elasticsearch/reference/current/search-request-body.html#_parameters_4) instead of "track\_total\_hits": false?
3. I am guessing the responses would be sorted in the order of the sort provided(In my example "rank"), but if I want to sort my responses based on BM25 instead I would need to perform [rescoring](https://www.elastic.co/guide/en/elasticsearch/reference/6.5/search-request-rescore.html#search-request-rescore), especially since the the score of each document is not returned.
4. Do I need to the additional "sort" key in my query since my index is sorted by default?

Simplified version of my Index Mappings

```
PUT test
{
  "settings": {
    "index": {
      "sort.field": [
        "rank"
      ],
      "sort.order": [
        "asc"
      ]
    }
  },
  "mappings": {
    "data": {
      "properties": {
        "my_field1": {
          "type": "text",
          "fields": {
            "keyword": {
              "type": "keyword",
              "ignore_above": 256
            }
          }
        },
        "my_field2": {
          "type": "text",
          "fields": {
            "keyword": {
              "type": "keyword",
              "ignore_above": 256
            }
          }
        },
        "rank": {
          "type": "integer"
        }
      }
    }
  }
}

```

Simplified version of my query

```
GET /test/_search
{
  "query": {
    "multi_match": {
      "query": "electric",
      "fields": ["my_field1", "my_field2"]
    }
  },
  "sort": [
    {
      "rank": {
        "order": "asc"
      }
    }
  ],
  "track_total_hits": false,
  "size": 1000
}
```

---

<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\
**Post date:** [August 19, 2019, 1:14am UTC](https://discuss.elastic.co/t/sorted-indices-and-early-termination/191553/2 "2019-08-19T01:14:54Z")

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