[[root-object]] === The Root Object
The uppermost level of a mapping is known ((("mapping (types)", "root object")))((("root object")))as the root object. It may contain the following:
A properties section, which lists the mapping for each field that a document may contain
Various metadata fields, all of which start with an underscore, such
as _type, _id, and _source
Settings, which control how the dynamic detection of new fields
is handled, such as analyzer, dynamic_date_formats, and
dynamic_templates
Other settings, which can be applied both to the root object and to fields
of type object, such as enabled, dynamic, and include_in_all
==== Properties
We have already discussed the three most important settings for document
fields or ((("root object", "properties")))((("properties", "important settings")))properties in <
type::
The datatype that the field contains, such as string or date
index::
Whether a field should be searchable as full text (analyzed), searchable as an exact value (not_analyzed), or not searchable at all (no)
analyzer::
Which analyzer to use for a full-text field, both at index time and at search time
We will discuss other field types such as ip, geo_point, and geo_shape in
the appropriate sections later in the book.
include::31_Metadata_source.asciidoc[]
include::32_Metadata_all.asciidoc[]
include::33_Metadata_ID.asciidoc[]