【入門】Elasticsearch とは？わかりやすく解説

version: '3'
services:
  elasticsearch:
    image: elasticsearch:7.12.1
    container_name: elasticsearch
    environment:
      - discovery.type=single-node
    ports:
      - 9200:9200
  kibana:
    image: kibana:7.12.1
    ports:
      - "5601:5601"
    environment:
      - ELASTICSEARCH_HOSTS=http://elasticsearch:9200

PUT /test/_doc/1
{
  "date":"2020/11/01 09:00 JST",
  "Tweet":"ツイッターをはじめました。",
  "User ID":"hoge"
}

{
  (中略)
  "_source" : {
    "date" : "2020/11/01 09:00 JST",
    "Tweet" : "ツイッターをはじめました。",
    "User ID" : "hoge"
  }
}

POST /test/_update/1
{
  "doc": {
    "Tweet":"フィールドを更新したよ。"
  }
}

POST /test/_doc/1
{
  "Tweet":"ドキュメントを置き換えたよ"
}

  "_version" : 3,
  "_source" : {
    "Tweet" : "ドキュメントを置き換えたよ"
  }

{
  "_index" : "test",
  "_type" : "_doc",
  "_id" : "1",
  "found" : false
}

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

POST /_bulk
{ "index" : { "_index" : "demo_search", "_id" : "1" } }
{ "text" : "This is Elasticsearch test.", "num" : 1 }
{ "index" : { "_index" : "demo_search", "_id" : "2" } }
{ "text" : "Elasticsearch is God.", "num" : 2 }
{ "index" : { "_index" : "demo_search", "_id" : "3" } }
{ "text" : "This is a pen.", "num" : 3 }

GET /demo_search/_search
{
  "query":{
    "match": {
      "text": {
        "query": "Elasticsearch god",
        "operator":"AND"
      }
    } 
  }
}

    "hits" : [
        (省略)
        "_source" : {
          "text" : "Elasticsearch is God."

GET /demo_search/_search
{
  "query":{
    "term": {
      "text.keyword": "This is Elasticsearch test."
    } 
  }
}

        "_source" : {
          "text" : "This is Elasticsearch test."

GET /demo_search/_search
{
  "query":{
    "range": {
      "num":{
        "gte": "1",
        "lte": "2"
      }
    } 
  }
}

    "hits" : [
      {
        "_index" : "demo_search",
        "_type" : "_doc",
        "_id" : "1",
        "_score" : 1.0,
        "_source" : {
          "text" : "This is Elasticsearch test.",
          "num" : 1
        }
      },
      {
        "_index" : "demo_search",
        "_type" : "_doc",
        "_id" : "2",
        "_score" : 1.0,
        "_source" : {
          "text" : "Elasticsearch is God.",
          "num" : 2
        }
      }

GET /demo_search/_search
{
  "query":{
    "bool": {
      "must":[
        {"match":{"text":"Elasticsearch"}},
        {"range":{"num":{"lte":"1"}}}
      ]
    } 
  }
}

        "_source" : {
          "text" : "This is Elasticsearch test.",
          "num" : 1
        }

GET /demo_search/_search
{
  "query":{
    "bool": {
      "should":[
        {"match":{"text":"God"}},
        {"range":{"num":{"gte":"2"}}}
      ]
    } 
  }
}

    "hits" : [
      {
        "_index" : "demo_search",
        "_type" : "_doc",
        "_id" : "2",
        "_score" : 2.0596457,
        "_source" : {
          "text" : "Elasticsearch is God.",
          "num" : 2
        }
      },
      {
        "_index" : "demo_search",
        "_type" : "_doc",
        "_id" : "3",
        "_score" : 1.0,
        "_source" : {
          "text" : "This is a pen.",
          "num" : 3

GET /demo_search/_search
{
  "query":{
    "bool": {
      "must_not":[
        {"match":{"text":"Elasticsearch"}},
        {"range":{"num":{"lte":"1"}}}
      ]
    } 
  }
}

    "hits" : [
      {
        "_index" : "demo_search",
        "_type" : "_doc",
        "_id" : "3",
        "_score" : 0.0,
        "_source" : {
          "text" : "This is a pen.",
          "num" : 3
        }
      }

GET /demo_search/_search
{
  "query":{
    "bool": {
      "must": [
        {"match":{"text":"Elasticsearch"}}
      ], 
      "filter":[
        {"range":{"num":{"lte":"1"}}}
      ]
    } 
  }
}

        "_source" : {
          "text" : "This is Elasticsearch test.",
          "num" : 1
        }

GET /demo_search/_search
{
  "sort": [
    {
      "num": {
        "order": "desc"
      }
    }
  ]
}

"_source" : {
          "text" : "This is a pen.",
          "num" : 3
        },
        "sort" : [
          3
        ]
        (中略)
        "_source" : {
          "text" : "Elasticsearch is God.",
          "num" : 2
        },
        "sort" : [
          2
        ]
        (中略)
        "_source" : {
          "text" : "This is Elasticsearch test.",
          "num" : 1
        },
        "sort" : [
          1
        ]