anchor.diff:  <titleabbrev>Get field mapping</titleabbrev>
   ++++
   
  -Retrieves <<mapping,mapping definitions>> for one or more fields. This is useful
  -if you don't need the <<indices-get-mapping,complete mapping>> of an index or
  -your index contains a large number of fields.
  +Retrieves <<mapping,mapping definitions>> for one or more fields. For data
  +streams, the API retrieves field mappings for the stream's backing indices.
  +
  +This API is useful if you don't need a <<indices-get-mapping,complete mapping>>
  +or if an index mapping contains a large number of fields.
   
   [source,console]
   ----
  
positive.code: --------------------------------------------------
  
  [[get-field-mapping-api-multi-index-ex]]
  ===== Multiple indices and fields
  
  The get field mapping API can be used to get the mapping of multiple fields from more than one index
  with a single call. General usage of the API follows the
  following syntax: `host:port/<index>/_mapping/field/<field>` where
  `<index>` and `<field>` can stand for comma-separated list of names or wild cards. To
  get mappings for all indices you can use `_all` for `<index>`. The
  following are some examples:
  
  [source,console]
  --------------------------------------------------
  GET /twitter,kimchy/_mapping/field/message
  
  GET /_all/_mapping/field/message,user.id
  
  GET /_all/_mapping/field/*.id
  --------------------------------------------------
  // TEST[setup:twitter]
  // TEST[s/^/PUT kimchy\nPUT book\n/]
  
negative.code: 
  `GET /_mapping/field/<field>`
  
  `GET /<target>/_mapping/field/<field>`
  
  
  [[get-field-mapping-api-path-params]]
  ==== {api-path-parms-title}
  
  `<target>`::
  (Optional, string)
  Comma-separated list of data streams, indices, and index aliases used to limit
  the request. Wildcard (`*`) expressions are supported.
  +
  To target all indices in a cluster, omit this parameter or use `_all` or `*`.
  
  `<field>`::
  (Optional, string) Comma-separated list or wildcard expression of fields used to
  