Elasticsearch核心技术与实战学习笔记第三章 11 | 文档的基本CRUD与批量操作

一序

本文属于极客时间Elasticsearch核心技术与实战学习笔记系列。

本节课学习文档的基本CRUD操作。

二文档CRUD

create

支持自动生成文档 Id 和指定文档 Id 两种方法.

1 自动生成文档 Id

#create document. 自动生成 _id
POST users/_doc
{
	"user" : "Mike",
    "post_date" : "2019-04-15T14:12:12",
    "message" : "trying out Kibana"
}

{
"_index" : "users",
"_type" : "_doc",
"_id" : "zQhRBHIBb3-P948QM8DK",
"_version" : 1,
"result" : "created",
"_shards" : {
"total" : 2,
"successful" : 2,
"failed" : 0
},
"_seq_no" : 1,
"_primary_term" : 1
}

#create document. 指定Id。如果id已经存在，报错
PUT users/_doc/1?op_type=create
{
    "user" : "Jack",
    "post_date" : "2019-05-15T14:12:12",
    "message" : "trying out Elasticsearch"
}

{
"_index" : "users",
"_type" : "_doc",
"_id" : "1",
"_version" : 1,
"result" : "created",
"_shards" : {
"total" : 2,
"successful" : 2,
"failed" : 0
},
"_seq_no" : 2,
"_primary_term" : 1
}

存在是提示：

{
"error": {
"root_cause": [
{
"type": "version_conflict_engine_exception",
"reason": "[1]: version conflict, document already exists (current version [1])",
"index_uuid": "fqVg1Y6NQHurMFOXu4fjQw",
"shard": "0",
"index": "users"
}
],
"type": "version_conflict_engine_exception",
"reason": "[1]: version conflict, document already exists (current version [1])",
"index_uuid": "fqVg1Y6NQHurMFOXu4fjQw",
"shard": "0",
"index": "users"
},
"status": 409
}

2、Get 一个文档

1）找到文档，返回 HTTP 200

GET users/_doc/1

其中，文档元信息

_index/_type/,_type 在版本7中只有 _doc 类型
_version 版本信息，同一个 Id 的文档被删除了，版本号也会增加
_source 中默认包含文档的原始信息

2）没找到文档，返回HTTP404

3 Index 文档

Index 也是用于创建文档的方法，和 Create 不同有一些不同，如果文档不存在情况，直接创建新文档，否者删除原来的文档，新文档被索引，_version 版本加一。

PUT users/_doc/1
{
"user" : "Mike"
}

3）index 操作后查看数据

4 、Update 文档

Update 方法不会删除原来文档，而是实现真正的数据更新
Post方法/Payload需要包含在 “doc”中

post结果：

{
"_index" : "users",
"_type" : "_doc",
"_id" : "1",
"_version" : 3,
"result" : "updated",
"_shards" : {
"total" : 2,
"successful" : 2,
"failed" : 0
},
"_seq_no" : 4,
"_primary_term" : 1
}

再次执行查询，多了两个字段

5、Delete 文档
1）通过id删除文档
2）请求中要包含在 “doc”中

# 删除文档
DELETE users/_doc/1

三、批量操作

脚本：

#执行第1次
POST _bulk
{ "index" : { "_index" : "test", "_id" : "1" } }
{ "field1" : "value1" }
{ "delete" : { "_index" : "test", "_id" : "2" } }
{ "create" : { "_index" : "test2", "_id" : "3" } }
{ "field1" : "value3" }
{ "update" : {"_id" : "1", "_index" : "test"} }
{ "doc" : {"field2" : "value2"} }

{
  "took" : 3665,
  "errors" : false,
  "items" : [
    {
      "index" : {
        "_index" : "test",
        "_type" : "_doc",
        "_id" : "1",
        "_version" : 1,
        "result" : "created",
        "_shards" : {
          "total" : 2,
          "successful" : 2,
          "failed" : 0
        },
        "_seq_no" : 0,
        "_primary_term" : 1,
        "status" : 201
      }
    },
    {
      "delete" : {
        "_index" : "test",
        "_type" : "_doc",
        "_id" : "2",
        "_version" : 1,
        "result" : "not_found",
        "_shards" : {
          "total" : 2,
          "successful" : 2,
          "failed" : 0
        },
        "_seq_no" : 1,
        "_primary_term" : 1,
        "status" : 404
      }
    },
    {
      "create" : {
        "_index" : "test2",
        "_type" : "_doc",
        "_id" : "3",
        "_version" : 1,
        "result" : "created",
        "_shards" : {
          "total" : 2,
          "successful" : 2,
          "failed" : 0
        },
        "_seq_no" : 0,
        "_primary_term" : 1,
        "status" : 201
      }
    },
    {
      "update" : {
        "_index" : "test",
        "_type" : "_doc",
        "_id" : "1",
        "_version" : 2,
        "result" : "updated",
        "_shards" : {
          "total" : 2,
          "successful" : 2,
          "failed" : 0
        },
        "_seq_no" : 2,
        "_primary_term" : 1,
        "status" : 200
      }
    }
  ]
}

2）批量读取-mget
批量操作，可以减少网络连接开销，提高性能
可以在docs中指定index，也可以在URL路径中指定index，

### mget 操作
GET /_mget
{
    "docs" : [
        {
            "_index" : "test",
            "_id" : "1"
        },
        {
            "_index" : "test",
            "_id" : "2"
        }
    ]
}

#URI中指定index
GET /test/_mget
{
    "docs" : [
        {

            "_id" : "1"
        },
        {

            "_id" : "2"
        }
    ]
}

3）批量查询-msearch
多个查询匹配条件组合

### msearch 操作
POST kibana_sample_data_ecommerce/_msearch
{}
{"query" : {"match_all" : {}},"size":1}
{"index" : "kibana_sample_data_flights"}
{"query" : {"match_all" : {}},"size":2}