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-fields


The index to which the document belongs.


The document’s mapping type.


The document’s ID.

Document source meta-fields

The original JSON representing the body of the document.
The size of the _source field in bytes, provided by the mapper-size plugin.

Indexing meta-fields

All fields in the document which contain non-null values.
All fields in the document that have been ignored at index time because of ignore_malformed.

Routing meta-field

A custom routing value which routes a document to a particular shard.

Other meta-field

Application specific metadata.