elasticsearch的index、create、update

[toc]

一. 查看集群健康、节点、分片

1.查看集群健康度

GET _cluster/health

{
  "cluster_name" : "elasticsearch",
  "status" : "yellow",
  "timed_out" : false,
  "number_of_nodes" : 1,
  "number_of_data_nodes" : 1,
  "active_primary_shards" : 8,
  "active_shards" : 8,
  "relocating_shards" : 0,
  "initializing_shards" : 0,
  "unassigned_shards" : 3,
  "delayed_unassigned_shards" : 0,
  "number_of_pending_tasks" : 0,
  "number_of_in_flight_fetch" : 0,
  "task_max_waiting_in_queue_millis" : 0,
  "active_shards_percent_as_number" : 72.72727272727273
}

2.查看节点信息

GET _cat/nodes

127.0.0.1 21 95 3 0.00 0.03 0.05 dilm * niewj

3. 查看分片信息

GET _cat/shards

.security-7                0 p STARTED       42  80.1kb 127.0.0.1 niewj
.apm-agent-configuration   0 p STARTED        0    283b 127.0.0.1 niewj
users                      0 p STARTED        4   5.3kb 127.0.0.1 niewj
users                      0 r UNASSIGNED                         
movies                     0 p STARTED     9743   1.3mb 127.0.0.1 niewj
movies                     0 r UNASSIGNED                         
.kibana_1                  0 p STARTED       88 101.9kb 127.0.0.1 niewj
kibana_sample_data_flights 0 p STARTED    13059   6.3mb 127.0.0.1 niewj
.kibana_task_manager_1     0 p STARTED        2  12.5kb 127.0.0.1 niewj
my_index                   0 p STARTED        2    10kb 127.0.0.1 niewj
my_index                   0 r UNASSIGNED

二. index、create、update文档

4. index一个文档

4.1 第一次index

PUT books/_doc/1
{
  "bookId":"1",
  "bookName":"Thinking in Java",
  "price": 99.99
}

结果：

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

再执行一次呢？

4.2 第一次index

PUT books/_doc/1
{
  "bookId":"1",
  "bookName":"Thinking in Java",
  "author": "Bruce Eckel"
}

输出如下：(为了看出区别，加了个"author"，减了个"price")

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

区别：

执行次数/区别	第一次	第二次
_version	1	2
result	created	updated
_seq_no	0	1

执行完后，index查询有没有"price"呢？有就说明是更新了，没有就说明是覆盖了：

GET books/_search
{
  "query": {"match_all": {}}
}

看看：

{
  "took" : 1002,
  "timed_out" : false,
  "_shards" : {
    "total" : 1,
    "successful" : 1,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : {
      "value" : 1,
      "relation" : "eq"
    },
    "max_score" : 1.0,
    "hits" : [
      {
        "_index" : "books",
        "_type" : "_doc",
        "_id" : "1",
        "_score" : 1.0,
        "_source" : {
          "bookId" : "1",
          "bookName" : "Thinking in Java",
          "author" : "Bruce Eckel"
        }
      }
    ]
  }
}

没price了！说明什么？

index时，如果id已存在，则先删除->再增加->_version+ _seq_no都会增加；
result 不同：第一次：created ; 第二次： updated

这里虽然是updated，但并不是只修改了原来的字段，而是先删，再建，昔有今无的字段是没的了！

就想一个商品房：新买的主人住进去一年，卖给第二个人，updated的是房间的状态，原来的主人，基本不会在那儿了！

5. create一个文档

5.1 第1种create方式：PUT idx名/_create/id串

第1次create

PUT books/_create/3
{
"bookId": "3",
"bookName": "中国通史",
"author": "吕思勉"
}

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

第2次create

{
  "error": {
    "root_cause": [
      {
        "type": "version_conflict_engine_exception",
        "reason": "[3]: version conflict, document already exists (current version [1])",
        "index_uuid": "64ki-Bg-SkeC6mTRY-7AnA",
        "shard": "0",
        "index": "books"
      }
    ],
    "type": "version_conflict_engine_exception",
    "reason": "[3]: version conflict, document already exists (current version [1])",
    "index_uuid": "64ki-Bg-SkeC6mTRY-7AnA",
    "shard": "0",
    "index": "books"
  },
  "status": 409
}

直接："status": 409了；报错了！

4xx的报错一般都是告诉你输入有问题

5.2 第2种create方式：POST idx名/_doc(自动生成ID)

POST books/_doc
{
  "bookId": "4",
  "bookName": "中国通史4",
  "author": "吕思勉"
}

连续执行了多次：

{
  "_index" : "books",
  "_type" : "_doc",
  "_id" : "OivOY4ABRxSL2QPxYNGs",
  "_version" : 1,
  "result" : "created",
  "_shards" : {
    "total" : 2,
    "successful" : 1,
    "failed" : 0
  },
  "_seq_no" : 10,
  "_primary_term" : 1
}

每次_id都不一样
_seq_no一直在增

因为每次都是存一个新文档了！查询看看：

{
  "took" : 627,
  "timed_out" : false,
  "_shards" : {
    "total" : 1,
    "successful" : 1,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : {
      "value" : 10,
      "relation" : "eq"
    },
    "max_score" : 1.0,
    "hits" : [
      {
        "_index" : "books",
        "_type" : "_doc",
        "_id" : "1",
        "_score" : 1.0,
        "_source" : {
          "bookId" : "1",
          "bookName" : "Thinking in Java",
          "author" : "Bruce Eckel"
        }
      },
      {
        "_index" : "books",
        "_type" : "_doc",
        "_id" : "2",
        "_score" : 1.0,
        "_source" : {
          "bookId" : "2",
          "bookName" : "中国通史",
          "author" : "吕思勉"
        }
      },
      {
        "_index" : "books",
        "_type" : "_doc",
        "_id" : "3",
        "_score" : 1.0,
        "_source" : {
          "bookId" : "3",
          "bookName" : "中国通史",
          "author" : "吕思勉"
        }
      },
      {
        "_index" : "books",
        "_type" : "_doc",
        "_id" : "NCvOY4ABRxSL2QPxNNHf",
        "_score" : 1.0,
        "_source" : {
          "bookId" : "4",
          "bookName" : "中国通史4",
          "author" : "吕思勉"
        }
      },
      {
        "_index" : "books",
        "_type" : "_doc",
        "_id" : "NSvOY4ABRxSL2QPxPdEy",
        "_score" : 1.0,
        "_source" : {
          "bookId" : "4",
          "bookName" : "中国通史4",
          "author" : "吕思勉"
        }
      },
      {
        "_index" : "books",
        "_type" : "_doc",
        "_id" : "NivOY4ABRxSL2QPxQdEo",
        "_score" : 1.0,
        "_source" : {
          "bookId" : "4",
          "bookName" : "中国通史4",
          "author" : "吕思勉"
        }
      },
      {
        "_index" : "books",
        "_type" : "_doc",
        "_id" : "NyvOY4ABRxSL2QPxRNHC",
        "_score" : 1.0,
        "_source" : {
          "bookId" : "4",
          "bookName" : "中国通史4",
          "author" : "吕思勉"
        }
      },
      {
        "_index" : "books",
        "_type" : "_doc",
        "_id" : "OCvOY4ABRxSL2QPxSdHA",
        "_score" : 1.0,
        "_source" : {
          "bookId" : "4",
          "bookName" : "中国通史4",
          "author" : "吕思勉"
        }
      },
      {
        "_index" : "books",
        "_type" : "_doc",
        "_id" : "OSvOY4ABRxSL2QPxTNHb",
        "_score" : 1.0,
        "_source" : {
          "bookId" : "4",
          "bookName" : "中国通史4",
          "author" : "吕思勉"
        }
      },
      {
        "_index" : "books",
        "_type" : "_doc",
        "_id" : "OivOY4ABRxSL2QPxYNGs",
        "_score" : 1.0,
        "_source" : {
          "bookId" : "4",
          "bookName" : "中国通史4",
          "author" : "吕思勉"
        }
      }
    ]
  }
}

这里就可以做一个小结：

6. index和create的区别

1.语法

index语法：PUT books/_doc/1

create语法：PUT books/_create/1 或者 POST books/_doc

2. 语义

index多次同一个id：会删除重建，但是版本一直++；

create的PUT books/_create/1 方式第二次执行会报错，而不是++版本号！

create支持自动生成id：此时的多次执行就是索引多份document了；

7. update文档

update一个已有文档：

POST books/_update/NCvOY4ABRxSL2QPxNNHf
{
  "doc": {
    "bookName": "鲁迅散文",
    "author": "鲁迅"
  }
}

查询看看：bookId并没有丢失，只是更新了赋值的字段

GET books/_search?q=_id:NCvOY4ABRxSL2QPxNNHf

{
  "took" : 2,
  "timed_out" : false,
  "_shards" : {
    "total" : 1,
    "successful" : 1,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : {
      "value" : 1,
      "relation" : "eq"
    },
    "max_score" : 1.0,
    "hits" : [
      {
        "_index" : "books",
        "_type" : "_doc",
        "_id" : "NCvOY4ABRxSL2QPxNNHf",
        "_score" : 1.0,
        "_source" : {
          "bookId" : "4",
          "bookName" : "鲁迅散文",
          "author" : "鲁迅"
        }
      }
    ]
  }
}

使用 GET books/_doc/NCvOY4ABRxSL2QPxNNHf可以看到版本：版本也发生了变化：update也会增加版本！

{
  "_index" : "books",
  "_type" : "_doc",
  "_id" : "NCvOY4ABRxSL2QPxNNHf",
  "_version" : 2,
  "_seq_no" : 11,
  "_primary_term" : 1,
  "found" : true,
  "_source" : {
    "bookId" : "4",
    "bookName" : "鲁迅散文",
    "author" : "鲁迅"
  }
}

三.创建索引

创建索引的3点总结

当index或者create文档时，如果索引不存在，就会自动创建索引；
同时mapping和setting会使用默认的（也可以自定义模板，如果模板匹配，模板就会起作用，此时创建的索引的mapping和setting就会被index template定义的内容约束）
默认mapping是dynamic=true的，就是有新增的字段，自动识别猜测类型；dynamic=false/strict时，就不会索引新的字段，区别是：strict直接报错不让增加新字段；false可以新增，_source里也会存入，但是字段不会被分词和生成索引，作为搜索条件去查询是也会报错！

四.删除索引

DELETE books

删除后再去查：GET books/_doc/1

{
  "error" : {
    "root_cause" : [
      {
        "type" : "index_not_found_exception",
        "reason" : "no such index [books1]",
        "resource.type" : "index_expression",
        "resource.id" : "books1",
        "index_uuid" : "_na_",
        "index" : "books1"
      }
    ],
    "type" : "index_not_found_exception",
    "reason" : "no such index [books1]",
    "resource.type" : "index_expression",
    "resource.id" : "books1",
    "index_uuid" : "_na_",
    "index" : "books1"
  },
  "status" : 404
}