Elasticsearch必知必會的干貨知識一：ES索引文檔的CRUD

小世界的野孩子 2022-04-16

展開全文

? 若在傳統(tǒng)DBMS 關系型數(shù)據(jù)庫中查詢海量數(shù)據(jù)，特別是模糊查詢，一般我們都是使用like %查詢的值%，但這樣會導致無法應用索引，從而形成全表掃描效率低下，即使是在有索引的字段精確值查找，面對海量數(shù)據(jù)，效率也是相對較低的，所以目前一般的互聯(lián)網(wǎng)公司或大型公司，若要查詢海量數(shù)據(jù)，最好的辦法就是使用搜索引擎，目前比較主流的搜索引擎框架就是：Elasticsearch，故今天我這里總結了Elasticsearch必知必會的干貨知識一：ES索引文檔的CRUD，后面陸續(xù)還會有其它干貨知識分享，敬請期待。

ES索引文檔的CRUD（6.X與7.X有區(qū)別，6.X中支持一個index創(chuàng)建多個type，而7.X中及以上只支持1個固定的type，即：_doc，API用法上也稍有不同）：

Create創(chuàng)建索引文檔【POST index/type/id可選，如果index、type、id已存在則重建索引文檔（先刪除后創(chuàng)建索引文檔，與Put index/type/id 原理相同），如果在指定id情況下需要限制自動更新，則可以使用：index/type/id?op_type=create 或 index/type/id/_create，指明操作類型為創(chuàng)建，這樣當存在的記錄的情況下會報錯】

POST demo_users/_doc 或 demo_users/_doc/2vJKsm8BriJODA6s9GbQ/_create

Request Body:
```
{
"userId":1,
"username":"張三",
"role":"administrator",
"enabled":true,
"createdDate":"2020-01-01T12:00:00"
}
```
Response Body:
```
{
"_index": "demo_users",
"_type": "_doc",
"_id": "2vJKsm8BriJODA6s9GbQ",
"_version": 1,
"result": "created",
"_shards": {
"total": 2,
"successful": 1,
"failed": 0
},
"_seq_no": 0,
"_primary_term": 1
}
```

Get獲取索引文檔【Get index/type/id】

Get demo_users/_doc/123

Response Body:

{
"_index": "demo_users",
"_type": "_doc",
"_id": "123",
"_version": 1,
"found": true,
"_source": {
"userId": 1,
"username": "張三",
"role": "administrator",
"enabled": true,
"createdDate": "2020-01-01T12:00:00"
}
}

Index Put重建索引文檔【PUT index/type/id 或 index/type/id?op_type=index，id必傳，如果id不存在文檔則創(chuàng)建文檔，否則先刪除原有id文檔后再重新創(chuàng)建文檔，version加1】

Put/POST demo_users/_doc/123 或 demo_users/_doc/123?op_type=index

Request Body:

{
"userId":1,
"username":"張三",
"role":"administrator",
"enabled":true,
"createdDate":"2020-01-01T12:00:00",
"remark":"僅演示"
}

Response Body:

{
"_index": "demo_users",
"_type": "_doc",
"_id": "123",
"_version": 4,
"result": "updated",
"_shards": {
"total": 2,
"successful": 2,
"failed": 0
},
"_seq_no": 10,
"_primary_term": 1
}

Update更新索引文檔【POST index/type/id/_update 請求體必需是{"doc":{具體的文檔JSON}},如果指定的鍵字段已存在則更新，如果指定的鍵字段不存在則附加新的鍵值對，支持多層級嵌套，多次請求，如果有字段值有更新則version加1，否則提示更新0條】

POST demo_users/_doc/123/_update

Request Body:

{
  "doc": {
    "userId": 1,
    "username": "張三",
    "role": "administrator",
    "enabled": true,
    "createdDate": "2020-01-01T12:00:00",
    "remark": "僅演示POST更新5",
    "updatedDate": "2020-01-17T15:30:00"
  }
}

Response Body:

{
"_index": "demo_users",
"_type": "_doc",
"_id": "123",
"_version": 26,
"result": "updated",
"_shards": {
"total": 2,
"successful": 2,
"failed": 0
},
"_seq_no": 35,
"_primary_term": 1
}

Delete刪除索引文檔【DELETE index/type/id】

DELETE demo_users/_doc/123

Response Body:

{
"_index": "demo_users",
"_type": "_doc",
"_id": "123",
"_version": 2,
"result": "deleted",
"_shards": {
"total": 2,
"successful": 2,
"failed": 0
},
"_seq_no": 39,
"_primary_term": 1
}

Bulk批量操作文檔【POST _bulk 或 index/_bulk 或 index/type/_bulk 一次請求支持進行多個索引、多個type的多種不同的CRUD操作，如果操作中有某個出現(xiàn)錯誤不會影響其它操作；】

POST _bulk

Request Body:(注意最后還得多一個換行，因為ES是根據(jù)換行符來識別多條命令的，如果缺少最后一條換行則會報錯，注意請求體非標準的JSON，每行才是一個JSON，整體頂多可看成是\n區(qū)分的JSON對象數(shù)組)

{ "index" : { "_index" : "demo_users_test", "_type" : "_doc", "_id" : "1" } }
{ "bulk_field1" : "測試創(chuàng)建index" }
{ "delete" : { "_index" : "demo_users", "_type" : "_doc", "_id" : "123" } }
{ "create" : { "_index" : "demo_users", "_type" : "_doc", "_id" : "2" } }
{ "bulk_field2" : "測試創(chuàng)建index2" }
{ "update" : { "_index" : "demo_users_test","_type" : "_doc","_id" : "1" } }
{ "doc": {"bulk_field1" : "測試創(chuàng)建index1","bulk_field2" : "測試創(chuàng)建index2"} }

Response Body:

{
    "took": 162,
    "errors": true,
    "items": [
        {
            "index": {
                "_index": "demo_users_test",
                "_type": "_doc",
                "_id": "1",
                "_version": 8,
                "result": "updated",
                "_shards": {
                    "total": 2,
                    "successful": 2,
                    "failed": 0
                },
                "_seq_no": 7,
                "_primary_term": 1,
                "status": 200
            }
        },
        {
            "delete": {
                "_index": "demo_users",
                "_type": "_doc",
                "_id": "123",
                "_version": 2,
                "result": "not_found",
                "_shards": {
                    "total": 2,
                    "successful": 2,
                    "failed": 0
                },
                "_seq_no": 44,
                "_primary_term": 1,
                "status": 404
            }
        },
        {
            "create": {
                "_index": "demo_users",
                "_type": "_doc",
                "_id": "2",
                "status": 409,
                "error": {
                    "type": "version_conflict_engine_exception",
                    "reason": "[_doc][2]: version conflict, document already exists (current version [1])",
                    "index_uuid": "u7WE286CQnGqhHeuwW7oyw",
                    "shard": "2",
                    "index": "demo_users"
                }
            }
        },
        {
            "update": {
                "_index": "demo_users_test",
                "_type": "_doc",
                "_id": "1",
                "_version": 9,
                "result": "updated",
                "_shards": {
                    "total": 2,
                    "successful": 2,
                    "failed": 0
                },
                "_seq_no": 8,
                "_primary_term": 1,
                "status": 200
            }
        }
    ]
}

mGet【POST _mget 或 index/_mget 或 index/type/_mget ，如果指定了index或type，則請求報文中則無需再指明index或type，可以通過_source指明要查詢的include以及要排除exclude的字段】

POST _mget

Request Body:

{
  "docs": [
    {
      "_index": "demo_users",
      "_type": "_doc",
      "_id": "12345"
    },
    {
      "_index": "demo_users",
      "_type": "_doc",
      "_id": "1234567",
      "_source": [
        "userId",
        "username",
        "role"
      ]
    },
    {
      "_index": "demo_users",
      "_type": "_doc",
      "_id": "1234",
      "_source": {
        "include": [
          "userId",
          "username"
        ],
        "exclude": [
          "role"
        ]
      }
    }
  ]
}

Response Body:

{
    "docs":[
        {
            "_index":"demo_users",
            "_type":"_doc",
            "_id":"12345",
            "_version":1,
            "found":true,
            "_source":{
                "userId":1,
                "username":"張三",
                "role":"administrator",
                "enabled":true,
                "createdDate":"2020-01-01T12:00:00"
            }
        },
        {
            "_index":"demo_users",
            "_type":"_doc",
            "_id":"1234567",
            "_version":7,
            "found":true,
            "_source":{
                "role":"administrator",
                "userId":1,
                "username":"張三"
            }
        },
        {
            "_index":"demo_users",
            "_type":"_doc",
            "_id":"1234",
            "_version":1,
            "found":true,
            "_source":{
                "userId":1,
                "username":"張三"
            }
        }
    ]
}

POST demo_users/_doc/_mget

Request Body:

{
  "ids": [
    "1234",
    "12345",
    "123457"
  ]
}

Response Body:

{
    "docs":[
        {
            "_index":"demo_users",
            "_type":"_doc",
            "_id":"1234",
            "_version":1,
            "found":true,
            "_source":{
                "userId":1,
                "username":"張三",
                "role":"administrator",
                "enabled":true,
                "createdDate":"2020-01-01T12:00:00",
                "remark":"僅演示"
            }
        },
        {
            "_index":"demo_users",
            "_type":"_doc",
            "_id":"12345",
            "_version":1,
            "found":true,
            "_source":{
                "userId":1,
                "username":"張三",
                "role":"administrator",
                "enabled":true,
                "createdDate":"2020-01-01T12:00:00"
            }
        },
        {
            "_index":"demo_users",
            "_type":"_doc",
            "_id":"123457",
            "found":false
        }
    ]
}

_update_by_query根據(jù)查詢條件更新匹配到的索引文檔的指定字段【POST index/_update_by_query 請求體寫查詢條件以及更新的字段，更新字段這里采用了painless腳本進行靈活更新】

POST demo_users/_update_by_query

Request Body:（意思是查詢role=administrator【可能大家看到keyword，這是因為role字段為text類型，無法直接匹配，需要借助于子字段role.keyword，如果有不理解后面會有簡要說明】，更新role為poweruser、remark為remark+采用_update_by_query更新）
```
{
    "script":{ "source":"ctx._source.role=params.role;ctx._source.remark=ctx._source.remark+params.remark",
        "lang":"painless",
        "params":{
            "role":"poweruser",
            "remark":"采用_update_by_query更新"
        }
    },
    "query":{
        "term":{
            "role.keyword":"administrator"
        }
    }
}
```
painless寫法請具體參考：painless語法教程

Response Body:
```
{
"took": 114,
"timed_out": false,
"total": 6,
"updated": 6,
"deleted": 0,
"batches": 1,
"version_conflicts": 0,
"noops": 0,
"retries": {
"bulk": 0,
"search": 0
},
"throttled_millis": 0,
"requests_per_second": -1,
"throttled_until_millis": 0,
"failures": [ ]
}
```

_delete_by_query根據(jù)查詢條件刪除匹配到的索引文檔【 POST index/_delete_by_query 請求體寫查詢匹配條件】

POST demo_users/_delete_by_query

Request Body:（意思是查詢enabled=false）

{
  "query": {
    "match": {
      "enabled": false
    }
  }
}

Response Body:

   {
           "took":29,
           "timed_out":false,
           "total":3,
           "deleted":3,
           "batches":1,
           "version_conflicts":0,
           "noops":0,
           "retries":{
               "bulk":0,
               "search":0
           },
           "throttled_millis":0,
           "requests_per_second":-1,
           "throttled_until_millis":0,
           "failures":[
       
           ]
      }

search查詢

URL GET查詢（GET index/_search?q=query_string語法，注意中文內(nèi)容默認分詞器是一個漢字拆分成一個term）


A.Term Query:【即分詞片段(詞條)查詢，注意這里講的包含是指與分詞片段匹配】
GET /demo_users/_search?q=role:poweruser //指定字段查詢,即：字段包含查詢的值

GET /demo_users/_search?q=poweruser //泛查詢(沒有指定查詢的字段)，即查詢文檔中所有字段包含poweruser的值，只要有一個字段符合，那么該文檔將會被返回

B.Phrase Query【即分組查詢】
操作符有：AND / OR  / NOT 或者表示為： && / || / ! 
+表示must -表示must_not 例如：field:(+a -b)意為field中必需包含a但不能包含b

GET /demo_users/_search?q=remark:(POST test) 
GET /demo_users/_search?q=remark:(POST OR test) 
GET /demo_users/_search?q=remark:"POST test" 
//分組查詢，即：查詢remark中包含POST 或 test的文檔記錄

GET /demo_users/_search?q=remark:(test AND POST) //remark同時包含test與POST
GET /demo_users/_search?q=remark:(test NOT POST) //remark包含test但不包含POST

C.范圍查詢
區(qū)間表示：[]閉區(qū)間，{}開區(qū)間
如：year:[2019 TO 2020] 或 {2019 TO 2020} 或 {2019 TO 2020] 或 [* TO 2020]
算數(shù)符號
year:>2019 或 (>2012 && <=2020) 或 (+>=2012 +<=2020)

GET /demo_users/_search?q=userId:>123 //查詢userId字段大于123的文檔記錄

D.通配符查詢
?表示匹配任意1個字符，*表示匹配0或多個字符 例如：role:power* , role:use?

GET /demo_users/_search?q=role:power* //查詢role字段前面是power，后面可以是0或多個其它任意字符。

可使用正則表達式，如：username:張三\d+

可使用近似查詢偏移量（slop）提高查詢匹配結果【使用~N，N表示偏移量】
GET /demo_users/_search?q=remark:tett~1 //查詢remark中包含test的文檔，但實際寫成了tett，故使用~1偏移近似查詢，可以獲得test的查詢結果

GET /demo_users/_search?q=remark:"i like shenzhen"~2 //查詢i like shenzhen但實際remark字段中值為：i like hubei and shenzhen，比查詢值多了 hubei and，這里使用~2指定可偏移相隔2個term（這里即兩個單詞），最終也是可以查詢出結果

DSL POST查詢（POST index/_search）

POST demo_users/_search

Request Body:

{
    "query":{
        "bool":{
            "must":[
                {
                    "term":{
                        "enabled":"true"  #查詢enabled=true
                    }
                },
                {
                    "term":{
                        "role.keyword":"poweruser" #且role=poweruser
                    }
                },
                {
                    "query_string":{
                        "default_field":"username.keyword",
                        "query":"張三" #且 username 包含張三
                    }
                }
            ],
            "must_not":[

            ],
            "should":[

            ]
        }
    },
    "from":0,
    "size":1000,
    "sort":[
        {
            "createdDate":"desc"  #根據(jù)createdDate倒序
        }
    ],
    "_source":{ #指明返回的字段，includes需返回字段，excludes不需要返回字段
        "includes":[
            "role",
            "username",
            "userId",
            "remark"
        ],
        "excludes":[

        ]
    }
}

具體用法可參見：

【Elasticsearch】query_string的各種用法

Elasticsearch中 match、match_phrase、query_string和term的區(qū)別

Elasticsearch Query DSL 整理總結

[布爾查詢Bool Query]