原文地址: https://www.elastic.co/guide/en/elasticsearch/reference/7.7/enabled.html, 原文档版权归 www.elastic.co 所有
IMPORTANT: No additional bug fixes or documentation updates will be released for this version. For the latest information, see the current release documentation.
Elasticsearch Guide [7.7] » Mapping » Mapping parameters » enabled
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enablededit

Elasticsearch tries to index all of the fields you give it, but sometimes you want to just store the field without indexing it. For instance, imagine that you are using Elasticsearch as a web session store. You may want to index the session ID and last update time, but you don’t need to query or run aggregations on the session data itself.

The enabled setting, which can be applied only to the top-level mapping definition and to object fields, causes Elasticsearch to skip parsing of the contents of the field entirely. The JSON can still be retrieved from the _source field, but it is not searchable or stored in any other way:

PUT my_index
{
  "mappings": {
    "properties": {
      "user_id": {
        "type":  "keyword"
      },
      "last_updated": {
        "type": "date"
      },
      "session_data": { 
        "type": "object",
        "enabled": false
      }
    }
  }
}

PUT my_index/_doc/session_1
{
  "user_id": "kimchy",
  "session_data": { 
    "arbitrary_object": {
      "some_array": [ "foo", "bar", { "baz": 2 } ]
    }
  },
  "last_updated": "2015-12-06T18:20:22"
}

PUT my_index/_doc/session_2
{
  "user_id": "jpountz",
  "session_data": "none", 
  "last_updated": "2015-12-06T18:22:13"
}

The session_data field is disabled.

Any arbitrary data can be passed to the session_data field as it will be entirely ignored.

The session_data will also ignore values that are not JSON objects.

The entire mapping may be disabled as well, in which case the document is stored in the _source field, which means it can be retrieved, but none of its contents are indexed in any way:

PUT my_index
{
  "mappings": {
    "enabled": false 
  }
}

PUT my_index/_doc/session_1
{
  "user_id": "kimchy",
  "session_data": {
    "arbitrary_object": {
      "some_array": [ "foo", "bar", { "baz": 2 } ]
    }
  },
  "last_updated": "2015-12-06T18:20:22"
}

GET my_index/_doc/session_1 

GET my_index/_mapping

The entire mapping is disabled.

The document can be retrieved.

Checking the mapping reveals that no fields have been added.

The enabled setting for existing fields and the top-level mapping definition cannot be updated.

Note that because Elasticsearch completely skips parsing the field contents, it is possible to add non-object data to a disabled field:

PUT my_index
{
  "mappings": {
    "properties": {
      "session_data": {
        "type": "object",
        "enabled": false
      }
    }
  }
}

PUT my_index/_doc/session_1
{
  "session_data": "foo bar" 
}

The document is added successfully, even though session_data contains non-object data.
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