http://192.168.32.81:9200/library/books/8/

                              GET

{

    "_index": "library",

    "_type": "books",

    "_id": "8",

    "_version": 1,

    "found": true,

    "_source": {

        "titile": "Elasticsearch: The Defintive Guide",

        "name": {

            "first": "Zachary",

            "last": "Tong"

        },

        "publish_date": "2016-07-29",

        "price": "90.01"

    }

}

此时版本为  "_version": 1,

http://192.168.32.81:9200/library/books/8/

_update                               POST

{

  "doc":{

      "price":"11.13"}

 }

{

    "_index": "library",

    "_type": "books",

    "_id": "8",

    "_version": 2,

    "found": true,

    "_source": {

        "titile": "Elasticsearch: The Defintive Guide",

        "name": {

            "first": "Zachary",

            "last": "Tong"

        },

        "publish_date": "2016-07-29",

        "price": "11.13"

    }

}

此时版本变为2