根据原文翻译整理
https://www.elastic.co/guide/en/elasticsearch/reference/5.0/indices-put-mapping.html


add a new type to an existing index
add new fields to an existing type
给存在的索引添加 type 
给存在的TYPE 添加字段

	
Creates an index called twitter with the message field in the tweet mapping type

PUT twitter 
{
  "mappings": {
    "tweet": {
      "properties": {
        "message": {
          "type": "text"
        }
      }
    }
  }
}

Uses the PUT mapping API to add a new mapping type called user.
添加新的TYPE user 

PUT twitter/_mapping/user 
{
  "properties": {
    "name": {
      "type": "text"
    }
  }
}

add a new field called user_name to the tweet mapping type
给tweet新增一个字段 user_name
PUT twitter/_mapping/tweet 
{
  "properties": {
    "user_name": {
      "type": "text"
    }
  }
}


the mapping for existing fields cannot be updated. 
 
 
new properties can be added to Object datatype fields.
new multi-fields can be added to existing fields.
doc_values can be disabled, but not enabled.
the ignore_above parameter can be updated.

doc_values可以被禁用 但不能被启用
ignore_above  字节数  超过指定长度的不会被处理

Lucene  字节长度限制 32766
如果使用 utf8    将这个限制设置成 32766 / 3 = 10922 ,一个 UTF-8 字符可能最多占用 3 个字节。

Fields in the same index with the same name in two different types must have the same mapping
同一个索引下的同名字段必须有同样的映射

Trying to update a mapping parameter for a field 
which exists in more than one type will throw an exception, 
unless you specify the update_all_types parameter, 
in which case it will update that parameter across all fields 
with the same name in the same index.

修改已存在同名字段的类型 使用 update_all_types

PUT my_index/_mapping/type_one?update_all_types 


获取 mapping 信息

GET /twitter/_mapping/tweet

GET /_mapping/tweet,kimchy

GET /_all/_mapping/tweet,book

GET /_all/_mapping

GET /_mapping

http://127.0.0.1:9200/_mapping


获取字段mapping信息
GET /twitter/_mapping/tweet/field/message
http://127.0.0.1:9200/twitter/_mapping/tweet/field/message

GET /twitter,kimchy/_mapping/field/message

GET /_all/_mapping/tweet,book/field/message,user.id

GET /_all/_mapping/tw*/field/*.id

使用 head 操作判断 type 是否存在

HEAD twitter/_mapping/tweet