3.基本操作

索引 index

创建

# 1.创建索引
- PUT/索引名====> PUT /products
- 注意:
	1.ES中索引健康转态red(索引不可用) 、yellwo(索引可用,存在风险)、green(健康)
	2.默认ES在创建索引时回为索引创建1个备份索引和一个primary索引
# 2.创建索引进行索引分片配置
PUT /products
{
	"settings" : {
		"number_of_shards" : 1，#指定主分片的数量
		"number_of_replicas" : 0 #指定副本分片的数量
	}
}

查询

# 查看es中的索引
GET /_cat/indices
# 查看es中的索引,同时查看状态
GET /_cat/indices?v

删除

# 删除索引
DELETE /products

没有修改的命令，除非删除

映射 mapping

创建

类型
字符串类型	keyword(关键字 关键词) 、 text(一段文本)
数字类型	integer long
小数类型	float double
布尔类型	boolean
日期类型	date

# 创建商品索引 products 指定 mapping{id,title,price,created_at,description}
PUT /products
{
  "settings": {
    "number_of_replicas": 0,
    "number_of_shards": 1
  },
  "mappings": {
    "properties": {
      "id":{
        "type": "integer"
      },
      "title":{
        "type": "keyword"
      },
      "price":{
        "type": "double"
      },
      "created_at":{
        "type": "date"
      },
      "description":{
        "type": "text"
      }
    }
  }
}

查看

# 查看某个索引的映射信息 mapping
GET /products/_mapping

需要注意，索引一旦创建，不能修改和删除。要删除只能通过删除映射再重新创建

文档 document

创建文档

在创建 索引 & 映射 之后 Json格式

POST /products/_doc/1 #指定文档id
{
	"title" : "iphone13" ,
	"price" : 8999.99,
	"created_at" : "2821-09-15”，
	"description" : "iPhone 13屏幕采用6.1英寸OLED屏幕。"
}

运行结果

{
  "_index": "products",
  "_id": "1",
  "_version": 6,
  "result": "updated",
  "_shards": {
    "total": 1,
    "successful": 1,
    "failed": 0
  },
  "_seq_no": 5,
  "_primary_term": 1
}

POST /products/_doc/ #自动生成文档id
{
	"title" : "iphone14" ,
	"price" : 8999.99,
	"created_at" : "2021-09-15",
	"description" : "iPhone 13屏幕采用6.8英寸OLED屏幕”
	}
}

运行结果

{
  "_index": "products",
  "_id": "CurihYsBq0CcYHMB1rPB",
  "_version": 1,
  "result": "created",
  "_shards": {
    "total": 1,
    "successful": 1,
    "failed": 0
  },
  "_seq_no": 6,
  "_primary_term": 1
}

文档查询

# 文档查询  基于 id 查询
GET /products/_doc/CurihYsBq0CcYHMB1rPB

删除文档

DELETE /products/_doc/CurihYsBq0CcYHMB1rPB

运行结果

{
  "_index": "products",
  "_id": "CurihYsBq0CcYHMB1rPB",
  "_version": 2,
  "result": "deleted",
  "_shards": {
    "total": 1,
    "successful": 1,
    "failed": 0
  },
  "_seq_no": 7,
  "_primary_term": 1
}

# 查询后
{
  "_index": "products",
  "_id": "CurihYsBq0CcYHMB1rPB",
  "found": false
}

更新文档

# 更新文档 
PUT /products/_doc/1
{
  "description":"小老鼠真香"
}

运行结果

{
  "_index": "products",
  "_id": "1",
  "_version": 7,
  "result": "updated",
  "_shards": {
    "total": 1,
    "successful": 1,
    "failed": 0
  },
  "_seq_no": 8,
  "_primary_term": 1
}

# 查看内容
{
  "_index": "products",
  "_id": "1",
  "_version": 7,
  "_seq_no": 8,
  "_primary_term": 1,
  "found": true,
  "_source": {
    "description": "小老鼠真香"
  }
}

# 更新文档，基于指定字段进行更新
POST /products/_doc/1/_update
{
  "doc":{
    "price":56.4,
    "title":"我是cfd"
  }
}

上面的是视频里面7.10的版本的写法，笔者所用的版本是8.10，产生了如下报错

{
  "error": "no handler found for uri [/products/_doc/1/_update?pretty=true] and method [POST]"
}

在官方文档查看正确用法如下

# 更新文档，基于指定字段进行更新
POST /products/_update/1
{
  "doc":{
    "price":1.0,
    "title":"我是cfddfc"
  }
}

【ElasticSearch（四）】PUT&POST更新数据、DELETE删除数据、_bulk批量操作 - musecho - 博客园 (cnblogs.com) Update API 官方8.10版本关于post更新的介绍，相比视频里面7的版本有些不同 | Elasticsearch Guide [8.10] | Elastic

批量操作

# 文档的批量操作 _bulk
# 不能有回车换行
POST ./products/_doc/_bulk
{"index":{"_id":2}}
  {"id" : 2,"title":"大老鼠","price":0.5,"created_at":"2012-11-12","description":"小浣熊真香！"}
{"index":{"_id":3}}
  {"id" : 2,"title":"与馒头","price":0.5,"created_at":"2012-11-12","description":"馒头真香啊"}

同样，7.0版本上面的用法是正确的，放在8.0版本里面就会报错，如下

{
  "error": {
    "root_cause": [
      {
        "type": "illegal_argument_exception",
        "reason": "Malformed content, found extra data after parsing: START_OBJECT"
      }
    ],
    "type": "illegal_argument_exception",
    "reason": "Malformed content, found extra data after parsing: START_OBJECT"
  },
  "status": 400
}

正确的用法

POST _bulk
{"index":{"_id":2,"_index" : "products"} }
{"id" : 2,"title":"大老鼠","price":0.5,"created_at":"2012-11-12","description":"小浣熊真香！"}
{"index":{"_id":3,"_index" : "products"} }
{"id" : 2,"title":"与馒头","price":0.5,"created_at":"2012-11-12","description":"馒头真香啊"}

批量不同操作

# 文档批量操作 添加 更新 删除
POST _bulk
{"index":{"_id":4,"_index" : "products"} }
{"id" : 4,"title":"好吃的薯片","price":100,"created_at":"2012-11-12","description":"薯片真香！"}
{"update":{"_id":3,"_index" : "products"} }
{"doc":{"description":"馒头太好吃了吧"}}
{"delete":{"_id":2,"_index" : "products"} }

结果如下，_bulk里的操作是非原子的，一个执行出错并不会妨碍其他的操作继续执行，在返回时按照执行的顺序返回消息。

{
  "errors": false,
  "took": 4,
  "items": [
    {
      "index": {
        "_index": "products",
        "_id": "4",
        "_version": 2,
        "result": "updated",
        "_shards": {
          "total": 1,
          "successful": 1,
          "failed": 0
        },
        "_seq_no": 28,
        "_primary_term": 2,
        "status": 200
      }
    },
    {
      "update": {
        "_index": "products",
        "_id": "3",
        "_version": 3,
        "result": "noop",
        "_shards": {
          "total": 1,
          "successful": 1,
          "failed": 0
        },
        "_seq_no": 26,
        "_primary_term": 2,
        "status": 200
      }
    },
    {
      "delete": {
        "_index": "products",
        "_id": "2",
        "_version": 4,
        "result": "not_found",
        "_shards": {
          "total": 1,
          "successful": 1,
          "failed": 0
        },
        "_seq_no": 29,
        "_primary_term": 2,
        "status": 404
      }
    }
  ]
}