Keyword datatypeedit

A field to index structured content such as email addresses, hostnames, status codes, zip codes or tags.

They are typically used for filtering (Find me all blog posts where status is published), for sorting, and for aggregations. Keyword fields are only searchable by their exact value.

If you need to index full text content such as email bodies or product descriptions, it is likely that you should rather use a text field.

Below is an example of a mapping for a keyword field:

PUT my_index
{
  "mappings": {
    "my_type": {
      "properties": {
        "tags": {
          "type":  "keyword"
        }
      }
    }
  }
}

Parameters for keyword fieldsedit

The following parameters are accepted by keyword fields:

boost

Mapping field-level query time boosting. Accepts a floating point number, defaults to 1.0.

doc_values

Should the field be stored on disk in a column-stride fashion, so that it can later be used for sorting, aggregations, or scripting? Accepts true (default) or false.

eager_global_ordinals

Should global ordinals be loaded eagerly on refresh? Accepts true or false (default). Enabling this is a good idea on fields that are frequently used for terms aggregations.

fields

Multi-fields allow the same string value to be indexed in multiple ways for different purposes, such as one field for search and a multi-field for sorting and aggregations.

ignore_above

Do not index any string longer than this value. Defaults to 2147483647 so that all values would be accepted.

include_in_all

Whether or not the field value should be included in the _all field? Accepts true or false. Defaults to false if index is set to no, or if a parent object field sets include_in_all to false. Otherwise defaults to true.

index

Should the field be searchable? Accepts true (default) or false.

index_options

What information should be stored in the index, for scoring purposes. Defaults to docs but can also be set to freqs to take term frequency into account when computing scores.

norms

Whether field-length should be taken into account when scoring queries. Accepts true or false (default).

null_value

Accepts a string value which is substituted for any explicit null values. Defaults to null, which means the field is treated as missing.

store

Whether the field value should be stored and retrievable separately from the _source field. Accepts true or false (default).

search_analyzer

The analyzer that should be used at search time on analyzed fields. Defaults to the analyzer setting.

similarity

Which scoring algorithm or similarity should be used. Defaults to classic, which uses TF/IDF.

normalizer

[experimental] This functionality is experimental and may be changed or removed completely in a future release. Elastic will take a best effort approach to fix any issues, but experimental features are not subject to the support SLA of official GA features. How to pre-process the keyword prior to indexing. Defaults to null, meaning the keyword is kept as-is.

Note

Indexes imported from 2.x do not support keyword. Instead they will attempt to downgrade keyword into string. This allows you to merge modern mappings with legacy mappings. Long lived indexes will have to be recreated before upgrading to 6.x but mapping downgrade gives you the opportunity to do the recreation on your own schedule.