﻿---
title: _tier field
description: When performing queries across multiple indexes, it is sometimes desirable to target indexes held on nodes of a given data tier (data_hot, data_warm,...
url: https://www.elastic.co/elastic/docs-builder/docs/3028/reference/elasticsearch/mapping-reference/mapping-tier-field
products:
  - Elasticsearch
applies_to:
  - Elastic Cloud Serverless: Generally available
  - Elastic Stack: Generally available
---

# _tier field
When performing queries across multiple indexes, it is sometimes desirable to target indexes held on nodes of a given data tier (`data_hot`, `data_warm`, `data_cold` or `data_frozen`). The `_tier` field allows matching on the `tier_preference` setting of the index a document was indexed into. The preferred value is accessible in certain queries :
```json

{
  "text": "Document in index 1"
}


{
  "text": "Document in index 2"
}


{
  "query": {
    "terms": {
      "_tier": ["data_hot", "data_warm"] <1>
    }
  }
}
```

Typically a query will use a `terms` query to list the tiers of interest but you can use the `_tier` field in any query that is rewritten to a `term` query, such as the `match`,  `query_string`, `term`, `terms`, or `simple_query_string` query, as well as `prefix` and `wildcard` queries. However, it does not support `regexp` and `fuzzy` queries.
The `tier_preference` setting of the index is a comma-delimited list of tier names in order of preference i.e. the preferred tier for hosting an index is listed first followed by potentially many fall-back options. Query matching only considers the first preference (the first value of a list).