Elasticsearch Search API 基础语法

Elasticsearch Search API 基础语法，文字内容来自 B 站中华石杉 Elasticsearch 顶尖高手系列课程核心知识篇，英文内容来自官方文档。

Search your data

A search query, or query, is a request for information about data in Elasticsearch data streams or indices.

A search consists of one or more queries that are combined and sent to Elasticsearch.

Search API 的基本语法

Search API: Returns search hits that match the query defined in the request.

Allows you to execute a search query and get back search hits that match the query.

Request

GET /<target>/_searchGET /_searchPOST /<target>/_searchPOST /_search

GET /my-index-000001/_search{  "query": {    "term": {	"user.id": "kimchy"    }  }}

挑了几个自己觉的重要的参数，抄了一下官方文档，挂一漏万。

Path parameters

<target> (Optional, string) Comma-separated list of data streams, indices, and index alias to search. Wildcard(*) expressions are support.

Query parameter

from: (Optional, integer) Starting document offset. Defaults to 0.

size: (Optional, integer) Defines the number of hits to return. Defaults to 10.

By default, you cannot page through more than 10,000 hits using the from and size parameters.

sort: (Optional, string) A comma-separated list of <field>:<direction> pairs.

source:

Request body

Response body

took: (integer) Milliseconds it took Elasticsearch to execute the request. This value is calculated by measuring the time elapsed between receipt of a request on the coordinating node and the time at which the coordinating node is ready to send the response.

Took time includes:

• Communication time between the coordinating node and data nodes

• Time the request spends in the search thread pool, queued for execution

• Actual execution time

Took time does not include:

• Time needed to send the request to Elasticsearch

• Time needed to serialize the JSON response

• Time needed to send the response to a client

time_out: (Boolean) If true, the request timed out before completion; returned results may be partial or empty.

hits: (object) Contains returned documents and metadata.

GET /_search
GET /index1,index2/_search
GET /_search{  "from": 0,  "size": 10}

GET or POST

http 协议中 get 是否可以带上 request body ?

HTTP 协议，一般不允许 get 请求带上 request body，但是因为 get 更加适合描述查询数据的操作，因此还是这么用了

GET /_search?from=0&size=10
POST /_search{  "from":0,  "size":10}

碰巧，很多浏览器，或者是服务器，也都支持 GET+request body 模式

如果遇到不支持的场景，也可以用 POST /_search