Elasticsearch 版本控制

内部版本控制：_version自增长，修改数据后，_version会自动加1外部版本控制：为了保持_version与外部版本控制的数值一致      使用version_type=external      检查数据当前的version值是否小于请求中的version值  PUT /library/books/1{  "title": "Elasticsearch: The Definitive Guide",  "name" : {    "first" : "Zachary",    "last" : "Tong"  },  "publish_date":"2015-02-06",  "price":"59.99"}查看数据:GET /library/books/1{  "_index": "library",  "_type": "books",  "_id": "1",  "_version": 1,  "found": true,  "_source": {    "title": "Elasticsearch: The Definitive Guide",    "name": {      "first": "Zachary",      "last": "Tong"    },    "publish_date": "2015-02-06",    "price": "59.99"  }}修改数据:POST /library/books/1/_update{  "doc": {     "price" : 10  }}此时版本为2：{  "_index": "library",  "_type": "books",  "_id": "1",  "_version": 2,  "_shards": {    "total": 2,    "successful": 1,    "failed": 0  }}指定版本去更新:POST /library/books/1/_update?version=3{  "doc": {     "price" : 15  }}{   "error": {      "root_cause": [         {            "type": "version_conflict_engine_exception",            "reason": "[books][1]: version conflict, current [2], provided [3]",            "shard": "3",            "index": "library"         }      ],      "type": "version_conflict_engine_exception",      "reason": "[books][1]: version conflict, current [2], provided [3]",      "shard": "3",      "index": "library"   },   "status": 409}