原文地址: https://www.elastic.co/guide/en/elasticsearch/reference/7.7/mapping-fields.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.
Meta-Fieldsedit
Each document has metadata associated with it, such as the _index, mapping
_type, and _id meta-fields. The behaviour of some of these meta-fields
can be customised when a mapping type is created.
Identity meta-fieldsedit
|
The index to which the document belongs. |
|
|
The document’s mapping type. |
|
|
The document’s ID. |
Document source meta-fieldsedit
-
_source - The original JSON representing the body of the document.
-
_size -
The size of the
_sourcefield in bytes, provided by themapper-sizeplugin.
Indexing meta-fieldsedit
-
_field_names - All fields in the document which contain non-null values.
-
_ignored -
All fields in the document that have been ignored at index time because of
ignore_malformed.
Routing meta-fieldedit
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_routing - A custom routing value which routes a document to a particular shard.
Other meta-fieldedit
-
_meta - Application specific metadata.