Elasticsearch常规"骚"操作

TechStyle 2021-02-15

1081

环境搭建

拉取elasticsearch镜像

docker pull elasticsearch:7.10.1

创建用户自定义网络

docker network create technetwork

容器运行ES

docker run --name elasticsearch --net technetwork -p 9200:9200 -p 9300:9300 -e "discovery.type=single-node" -d elasticsearch:7.10.1

查看ES

http://localhost:9200

拉取kibana镜像

docker pull kibana:7.10.1

容器运行kibana

docker run --name kibana --net technetwork -p 5601:5601 -d kibana:7.10.1

查看kibana，并切换到Dev Tools

http://localhost:5601

ES 和 RDBMS 区别

RDBMS - schema / transaction / join
Elasticsearch - schemaless / correlation / High performance full-text retrieval

RDBMS	Elasticsearch
Table	Index(Type)
Row	Document
Column	Field
Schema	Mapping
SQL	DSL

Note:

ES7.0之前，一个Index可以设置多个Type。
ES7.0开始，Type已经被deprecated，一个Index只能设置一个Type —— “_doc”。

ES CRUD

Create	PUT my_index/_doc/1 { "username": "techstyle", "password": "123456", "city": "shanghai" }
Read	GET my_index/_doc/1
Update	POST my_index/_doc/1 { "username": "techstyle", "password": "654321", "city": "beijing" }
Delete	DELETE my_index/_doc/1 DELETE my_index

Note:

ES中创建index使用的是PUT，更新index使用的是POST

Index Settings

GET my_index/_settings

Index Mapping

GET my_index/_mapping

Index Alias

add alias to index

POST /_aliases
{
  "actions": [{
    "add": {
      "index": "my_index",
      "alias": "techindex"
    }
  }]
}

remove alias from index

POST /_aliases
{
  "actions": [{
    "remove": {
      "index": "my_index",
      "alias": "techindex3"
    }
  }]
}

get all aliases start from 'tech'

GET _cat/aliases?v&alias=tech*

get by alias

# get By alias
GET techindex/_doc/1
# get by index
GET my_index/_doc/1

Search Template

prepare initial index data

create search template

POST _scripts/my_template
{
  "script": {
    "lang": "mustache",
    "source": {
      "query": {
        "multi_match": {
          "fields": [
            "username"
          ],
          "query": "{{query_string}}"
        }
      }
    }
  }
}

Note: 这里仅仅匹配 'username'

get template

GET _scripts/my_template

search by template

POST my_index/_search/template
{
  "id": "my_template",
  "params": {
    "query_string": "beijing"
  }
}

Note: 查询 'username=beijing' 的 doc，仅命中1个

delete template

DELETE _scripts/my_template

重新创建一个匹配 username 和 city 的 search template

POST _scripts/my_template
{
  "script": {
    "lang": "mustache",
    "source": {
      "query": {
        "multi_match": {
          "fields": [
            "username",
            "city"
          ],
          "query": "{{query_string}}"
        }
      }
    }
  }
}

再次使用 search template 进行模板查询，命中了2个

Pipeline

ES内部有许多内置的processor，比如date、append、join、split、convert、script等，具体可以参考如下链接

https://www.elastic.co/guide/en/elasticsearch/reference/current/ingest-processors.html

这里为了演示方便就新建一个convert pipeline，将price字段转为float类型

PUT _ingest/pipeline/my_pipeline
{
  "description": "update from string to double",
  "processors": [
    {
      "convert": {
        "field": "price",
        "type": "float"
      }
    }
  ]
}

simulate看下新建的pipeline的效果

POST _ingest/pipeline/my_pipeline/_simulate
{
  "docs": [
    {
      "_index": "index",
      "_id": "id",
      "_source": {
        "product": "Macbook",
        "price": "999"
      }
    },
    {
      "_index": "index",
      "_id": "id",
      "_source": {
        "product": "iPhone",
        "price": "666"
      }
    }
  ]
}

可以看到price字段全部转为了float类型

查看自定义的convert pipeline

GET _ingest/pipeline/my_pipeline

创建index的时候启用自定义的convert pipeline

PUT my_index/_doc/4?pipeline=my_pipeline
{
  "product": "iPad",
  "price": "999"
}

查看新创建的index的doc内容，可以看到price字段已经convert为float类型

删除自定义的convert pipeline

DELETE _ingest/pipeline/my_pipeline

Reference

https://hub.docker.com/_/elasticsearch

https://hub.docker.com/_/kibana

https://www.elastic.co/downloads/elasticsearch

https://www.elastic.co/downloads/kibana

https://www.elastic.co/guide/en/elasticsearch/reference/current/indices.html

https://www.elastic.co/guide/en/elasticsearch/reference/current/index-templates.html

https://www.elastic.co/guide/en/elasticsearch/reference/current/search-template.html

https://www.elastic.co/guide/en/elasticsearch/reference/current/modules-scripting.html

https://www.elastic.co/guide/en/elasticsearch/reference/current/pipeline.html

https://www.elastic.co/guide/en/elasticsearch/reference/current/ingest-apis.html

https://www.elastic.co/guide/en/elasticsearch/reference/current/removal-of-types.html

https://www.elastic.co/guide/en/elasticsearch/reference/current/indices-get-settings.html

泰克风格只讲干货不弄玄虚

数据库 elasticsearch

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Elasticsearch常规"骚"操作

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