Constant keyword field type

Introduced 2.14

A constant keyword field uses the same value for all documents in the index.

When a search request spans multiple indexes, you can filter on a constant keyword field to match documents from indexes with the given constant value but not from indexes with a different value.

Example

The following query creates a mapping with a constant keyword field:

PUT romcom_movies
{
  "mappings" : {
    "properties" : {
      "genre" : {
        "type": "constant_keyword",
        "value" : "Romantic comedy"
      }
    }
  }
}

copy

Parameters

The following table lists the parameters accepted by constant keyword field types. All values are required.