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2024-10-21 20:58:50 +08:00
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@@ -170,6 +170,322 @@ POST books/_doc
"_primary_term": 1 "_primary_term": 1
} }
``` ```
#### 向索引中添加多个document
可以使用`/_bulk`接口来在单个请求中添加多个document。`_bulk`请求的请求体由多个json串组成json串之间通过换行符分隔。
bulk请求示例如下所示
```
POST /_bulk
{ "index" : { "_index" : "books" } }
{"name": "Revelation Space", "author": "Alastair Reynolds", "release_date": "2000-03-15", "page_count": 585}
{ "index" : { "_index" : "books" } }
{"name": "1984", "author": "George Orwell", "release_date": "1985-06-01", "page_count": 328}
{ "index" : { "_index" : "books" } }
{"name": "Fahrenheit 451", "author": "Ray Bradbury", "release_date": "1953-10-15", "page_count": 227}
{ "index" : { "_index" : "books" } }
{"name": "Brave New World", "author": "Aldous Huxley", "release_date": "1932-06-01", "page_count": 268}
{ "index" : { "_index" : "books" } }
{"name": "The Handmaids Tale", "author": "Margaret Atwood", "release_date": "1985-06-01", "page_count": 311}
```
如果上述请求被正确处理,将会得到如下返回体:
```json
{
"errors": false,
"took": 29,
"items": [
{
"index": {
"_index": "books",
"_id": "QklI2IsBaSa7VYx_Qkh-",
"_version": 1,
"result": "created",
"_shards": {
"total": 2,
"successful": 2,
"failed": 0
},
"_seq_no": 1,
"_primary_term": 1,
"status": 201
}
},
{
"index": {
"_index": "books",
"_id": "Q0lI2IsBaSa7VYx_Qkh-",
"_version": 1,
"result": "created",
"_shards": {
"total": 2,
"successful": 2,
"failed": 0
},
"_seq_no": 2,
"_primary_term": 1,
"status": 201
}
},
{
"index": {
"_index": "books",
"_id": "RElI2IsBaSa7VYx_Qkh-",
"_version": 1,
"result": "created",
"_shards": {
"total": 2,
"successful": 2,
"failed": 0
},
"_seq_no": 3,
"_primary_term": 1,
"status": 201
}
},
{
"index": {
"_index": "books",
"_id": "RUlI2IsBaSa7VYx_Qkh-",
"_version": 1,
"result": "created",
"_shards": {
"total": 2,
"successful": 2,
"failed": 0
},
"_seq_no": 4,
"_primary_term": 1,
"status": 201
}
},
{
"index": {
"_index": "books",
"_id": "RklI2IsBaSa7VYx_Qkh-",
"_version": 1,
"result": "created",
"_shards": {
"total": 2,
"successful": 2,
"failed": 0
},
"_seq_no": 5,
"_primary_term": 1,
"status": 201
}
}
]
}
```
### 定义mapping和data type
#### 使用dynamic mapping
当使用dynamic mapping时elastic search默认情况下将会自动为新field创建mapping。上述示例中向索引中添加的document都使用了dynamic mapping因为在创建索引时并没有手动指定mapping。
可以向`books`索引中新增一个document新增document中包含当前索引documents中不存在的字段
```
POST /books/_doc
{
"name": "The Great Gatsby",
"author": "F. Scott Fitzgerald",
"release_date": "1925-04-10",
"page_count": 180,
"language": "EN"
}
```
此时,针对`books`索引,新字段`language`之前并不存在,会以`text`的data type被新增到mapping中。
可以通过`/{index_uid}/_mapping`请求来查看索引的mapping信息
```
GET /books/_mapping
```
其返回的响应为:
```json
{
"books": {
"mappings": {
"properties": {
"author": {
"type": "text",
"fields": {
"keyword": {
"type": "keyword",
"ignore_above": 256
}
}
},
"name": {
"type": "text",
"fields": {
"keyword": {
"type": "keyword",
"ignore_above": 256
}
}
},
"new_field": {
"type": "text",
"fields": {
"keyword": {
"type": "keyword",
"ignore_above": 256
}
}
},
"page_count": {
"type": "long"
},
"release_date": {
"type": "date"
}
}
}
}
}
```
#### 手动指定索引的mapping
如下示例会展示如何在创建索引时手动指定索引的mapping
```
PUT /my-explicit-mappings-books
{
"mappings": {
"dynamic": false,
"properties": {
"name": { "type": "text" },
"author": { "type": "text" },
"release_date": { "type": "date", "format": "yyyy-MM-dd" },
"page_count": { "type": "integer" }
}
}
}
```
上述示例中请求体含义如下:
- `"dynamic": false`: 在索引中禁用dynamic mapping如果提交的document中包含了mapping中不存在的field那么该提交的document将会被拒绝
- `"properties"`properties属性定义了document中的fields及其数据类型
#### 将dynamic mapping和手动指定mapping相结合
如果在创建索引时手动指定了索引的mapping那么在向索引中添加document时document必须符合索引的定义。
如果要结合dynamic mapping和手动指定mapping有如下两种方式
- 使用update mapping Api
- 手动指定mapping时将dynamic设置为true此时向document中添加new field时无需对mapping执行update
### 搜索索引
#### 搜索所有文档
```
GET books/_search
```
上述请求将会搜索`books`索引中所有的文档
响应如下:
```json
{
"took": 2,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 7,
"relation": "eq"
},
"max_score": 1,
"hits": [
{
"_index": "books",
"_id": "CwICQpIBO6vvGGiC_3Ls",
"_score": 1,
"_source": {
"name": "Brave New World",
"author": "Aldous Huxley",
"release_date": "1932-06-01",
"page_count": 268
}
},
... (truncated)
]
}
}
```
其中,响应体的字段含义如下:
- `took`es执行该搜索请求花费的时间单位为ms
- `time_out`:代表该请求是否超时
- `_shards`:代表该请求的分片数和成功数
- `hits`hits对象中包含了执行结果
- `total`total对象中包含了匹配结果的总数信息
- `max_score`max_score包含了在所有匹配documents中最高的relavance score
- `_index`该字段代表了document所属的索引
- `_id`该字段代表document的唯一标识id
- `_score``_score`字段代表当前document的relavance score
- `_source`该字段包含了indexing过程中提交的原始json对象
#### match请求
可以通过match请求来查询特定field中包含指定值的documents。这是全文本查询的标准查询。
如下示例中会查询索引中`name` field中包含`brave`的文档:
```
GET books/_search
{
"query": {
"match": {
"name": "brave"
}
}
}
```
响应体结构如下:
```json
{
"took": 9,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 1,
"relation": "eq"
},
"max_score": 0.6931471,
"hits": [
{
"_index": "books",
"_id": "CwICQpIBO6vvGGiC_3Ls",
"_score": 0.6931471,
"_source": {
"name": "Brave New World",
"author": "Aldous Huxley",
"release_date": "1932-06-01",
"page_count": 268
}
}
]
}
}
```
#### 删除索引
如果要删除创建的索引从头开始,可以使用如下方式:
```
DELETE /books
DELETE /my-explicit-mappings-books
```
删除索引将会永久删除其document、shards、元数据。