Elasticsearch是一个开源的高扩展的分布式、RESTful风格的搜索和数据分析引擎，能够解决不断涌现出的各种用例。
本文使用Elasticsearch7.12.0版本，使用Postman作为客户端访问工具
Elasticsearch数据格式
Elasticsearch是面向文档型数据库，一条数据在此就是一个文档，与MySQL对比如下：
ES里的Index可以看作是一个库，Types相当于表，Documents相当于表的行。在ES7.x中，Type的概念已经被删除
索引操作
创建索引
相当于关系型数据库中创建数据库，在Postman中使用PUT类型发起请求：http://localhost:9200/user
返回数据：
{
"acknowledged": true,
"shards_acknowledged": true,
"index": "user"
}
acknowledged：响应结果
shards_acknowledged：分片结果
index：索引名称
如果重复添加会返回错误信息，索引已存在
{
"error": {
"root_cause": [
{
"type": "resource_already_exists_exception",
"reason": "index [user/zF9iWH0dR-2Xt_dmr5BPZg] already exists",
"index_uuid": "zF9iWH0dR-2Xt_dmr5BPZg",
"index": "user"
}
],
"type": "resource_already_exists_exception",
"reason": "index [user/zF9iWH0dR-2Xt_dmr5BPZg] already exists",
"index_uuid": "zF9iWH0dR-2Xt_dmr5BPZg",
"index": "user"
},
"status": 400
}
查看所有索引
在Postman中，使用GET类型发起请求：http://localhost:9200/_cat/indices?v
_cat表示查看，indices表示索引
返回结果：
health status index uuid pri rep docs.count docs.deleted store.size pri.store.size
yellow open user zF9iWH0dR-2Xt_dmr5BPZg 1 1 0 0 208b 208b
| 字段 | 解释 |
|---|---|
| health | 当前服务器健康状态:green(集群完整);yellow(单点正常/集群不完整);red(单点不正常) |
| status | 索引打开/关闭状态 |
| index | 索引名 |
| uuid | 索引统一编号 |
| pri | 主分片数量 |
| rep | 副本数量 |
| docs.count | 可用文档数量 |
| docs.deleted | 文档删除状态(逻辑删除) |
| store.size | 主分片和副分片整体占空间大小 |
| pri.store.size | 主分片占空间大小 |
查看单个索引
在Postman中，使用GET类型发起请求：http://localhost:9200/user
{
"user": {
"aliases": {},
"mappings": {},
"settings": {
"index": {
"routing": {
"allocation": {
"include": {
"_tier_preference": "data_content"
}
}
},
"number_of_shards": "1",
"provided_name": "user",
"creation_date": "1618148948222",
"number_of_replicas": "1",
"uuid": "zF9iWH0dR-2Xt_dmr5BPZg",
"version": {
"created": "7120099"
}
}
}
}
}
注意：查看索引和创建索引的请求路径都是一样的，不同的是请求方式不同
删除索引
在Postman中，使用DELETE类型发起请求：http://localhost:9200/user
返回结果：
{
"acknowledged": true
}
重新访问索引时，会返回响应：索引不存在
{
"error": {
"root_cause": [
{
"type": "index_not_found_exception",
"reason": "no such index [user]",
"resource.type": "index_or_alias",
"resource.id": "user",
"index_uuid": "_na_",
"index": "user"
}
],
"type": "index_not_found_exception",
"reason": "no such index [user]",
"resource.type": "index_or_alias",
"resource.id": "user",
"index_uuid": "_na_",
"index": "user"
},
"status": 404
}
文档操作
类似于关系型数据库中的表数据
创建文档
在Postman中，使用POST类型发起请求：http://localhost:9200/user/_doc
{
"id": 100,
"name": "张宝芸",
"age": 18,
"salary": 6000
}
响应结果为：
{
"_index": "user",
"_type": "_doc",
"_id": "nU1ewXgBnzNOgvN8P7th",
"_version": 1,
"result": "created",
"_shards": {
"total": 2,
"successful": 1,
"failed": 0
},
"_seq_no": 0,
"_primary_term": 1
}
_id是唯一性标识，如果没有指定，ES服务器会随机生成，如果需要自定义唯一性标识，需要在创建时指定id，即http://localhost:9200/user/_doc/1
注意：如果不指定主键，请求类型只能是POST，如果指定主键，请求类型可以是PUT
查看文档
在Postman中，使用GET请求类型发起请求：http://localhost:9200/user/_doc/1
响应结果：
{
"_index": "user",
"_type": "_doc",
"_id": "1",
"_version": 1,
"_seq_no": 1,
"_primary_term": 1,
"found": true,
"_source": {
"id": 101,
"name": "萧峰",
"age": 20,
"salary": 8000
}
}
其中found表示查询结果，true表示查询到，false表示未查询到
修改文档
在Postman中，使用POST类型发起请求：http://localhost:9200/user/_doc/1
响应结果：
{
"_index": "user",
"_type": "_doc",
"_id": "1",
"_version": 2,
"result": "updated",
"_shards": {
"total": 2,
"successful": 1,
"failed": 0
},
"_seq_no": 2,
"_primary_term": 1
}
其中result表示结果，updated表示数据被更新
修改字段
也可以只修改某一条数据的局部信息
在Postman中，发起POST类型的请求：http://localhost:9200/user/_update/1
{
"doc": {
"salary": 12000
}
}
响应结果：
{
"_index": "user",
"_type": "_doc",
"_id": "1",
"_version": 3,
"result": "updated",
"_shards": {
"total": 2,
"successful": 1,
"failed": 0
},
"_seq_no": 3,
"_primary_term": 1
}
根据唯一性标识，查询文档数据发现已修改，http://localhost:9200/user/_doc/1
{
"_index": "user",
"_type": "_doc",
"_id": "1",
"_version": 3,
"_seq_no": 3,
"_primary_term": 1,
"found": true,
"_source": {
"id": 101,
"name": "萧峰",
"age": 22,
"salary": 12000
}
}
删除文档
删除文档时只会进行逻辑删除
在Postman中，发起DELETE类型请求：http://localhost:9200/user/_doc/1
响应结果为：
{
"_index": "user",
"_type": "_doc",
"_id": "1",
"_version": 4,
"result": "deleted",
"_shards": {
"total": 2,
"successful": 1,
"failed": 0
},
"_seq_no": 4,
"_primary_term": 1
}
其中result表示结果，deleted表示数据被标记为删除
删除文档数据后，再次查询会提示找不到
{
"_index": "user",
"_type": "_doc",
"_id": "1",
"found": false
}
如果删除一个不存在的文档，result显示not_found
{
"_index": "user",
"_type": "_doc",
"_id": "1",
"_version": 1,
"result": "not_found",
"_shards": {
"total": 2,
"successful": 1,
"failed": 0
},
"_seq_no": 5,
"_primary_term": 1
}
条件删除文档
删除数据时可以根据唯一性标识进行删除，也可以根据条件对对多条数据进行删除
在Postman中，发起POST类型请求：http://localhost:9200/user/_delete_by_query
{
"query": {
"match": {
"salary": 6000
}
}
}
响应结果为：
{
"took": 47,
"timed_out": false,
"total": 1,
"deleted": 1,
"batches": 1,
"version_conflicts": 0,
"noops": 0,
"retries": {
"bulk": 0,
"search": 0
},
"throttled_millis": 0,
"requests_per_second": -1.0,
"throttled_until_millis": 0,
"failures": []
}
其中took表示耗时，timed_out表示是否超时，deleted表示删除数量
映射操作
索引创建后，就可以建索引库中的映射，类似于关系型数据库中的表结构(table)
创建映射
在Postman中，发起PUT类型请求：http://localhost:9200/user/_mapping
{
"properties": {
"name": {
"type": "text",
"index": true
},
"sex": {
"type": "text",
"index": false
},
"age": {
"type": "long",
"index": false
}
}
}
响应结果为：
{
"acknowledged": true
}
说明：
字段名：可以随意填写
type：类型
String类型：text：可分词；keyword：不可分词
Numerical数值类型：
基本数据类型：long、integer、short、byte、double、float、half_float
浮点数高精度类型：scaled_float
Date日期类型
Array数组类型
Object对象
index：是否索引，默认true，字段会被索引，可以用来进行搜索；false，字段不会被索引，不能用于搜索
store：是否将数据进行独立存储，默认false
analyzer：分词器
查看映射
在Postman中，发起GET类型请求：http://localhost:9200/user/_mapping
响应结果为：
{
"user": {
"mappings": {
"properties": {
"age": {
"type": "long",
"index": false
},
"name": {
"type": "text"
},
"sex": {
"type": "text",
"index": false
}
}
}
}
}
索引映射关联
在Postman中，发起PUT类型请求：http://localhost:9200/userinfo
请求报文为：
{
"settings": {
},
"mappings": {
"properties": {
"name": {
"type": "text",
"index": true
},
"sex": {
"type": "text",
"index": false
},
"age": {
"type": "long",
"index": false
}
}
}
}
响应结果为：
{
"acknowledged": true,
"shards_acknowledged": true,
"index": "userinfo"
}
高级查询
ES提供了基于JSON的查询DSL来定义查询
查询所有文档
在Postman中，发起GET类型请求：http://localhost:9200/user/_search
请求报文为：
{
"query": {
"match_all": {
}
}
}
“query”：表示一个查询对象，可以有不同的查询属性
“match_all”：查询类型
响应结果为：
{
"took": 517,//查询时间，单位ms
"timed_out": false,//是否超时
"_shards": {//分片信息
"total": 1,//总数
"successful": 1,//成功
"skipped": 0,//忽略
"failed": 0//失败
},
"hits": {//搜索命中结果
"total": {//搜索条件匹配的文档总数
"value": 5,//总命中计数的值
"relation": "eq"//计数规则，eq表示计数准确，gte表示计数不准确
},
"max_score": 1.0,//匹配度分值
"hits": [//命中结果集合
{
"_index": "user",
"_type": "_doc",
"_id": "101",
"_score": 1.0,
"_source": {
"name": "zhangwuji",
"nickname": "教主",
"sex": "男",
"age": 30
}
},
{
"_index": "user",
"_type": "_doc",
"_id": "102",
"_score": 1.0,
"_source": {
"name": "xiaofeng",
"nickname": "帮主",
"sex": "男",
"age": 32
}
},
{
"_index": "user",
"_type": "_doc",
"_id": "103",
"_score": 1.0,
"_source": {
"name": "zhaomin",
"nickname": "郡主",
"sex": "女",
"age": 22
}
},
{
"_index": "user",
"_type": "_doc",
"_id": "104",
"_score": 1.0,
"_source": {
"name": "xiaolongnv",
"nickname": "古墓派",
"sex": "女",
"age": 18
}
},
{
"_index": "user",
"_type": "_doc",
"_id": "105",
"_score": 1.0,
"_source": {
"name": "mafuren",
"nickname": "丐帮夫人",
"sex": "女",
"age": 30
}
}
]
}
}
匹配查询
match匹配类型查询，会把查询条件进行分词，然后进行查询，多个词条之间是or的关系。
在Postman中，发起GET类型请求：http://localhost:9200/user/_search
请求报文为：
{
"query": {
"match": {
"name": "xiaofeng"
}
}
}
响应结果为：
{
"took": 23,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 1,
"relation": "eq"
},
"max_score": 1.3862942,
"hits": [
{
"_index": "user",
"_type": "_doc",
"_id": "102",
"_score": 1.3862942,
"_source": {
"name": "xiaofeng",
"nickname": "帮主",
"sex": "男",
"age": 32
}
}
]
}
}
字段匹配查询
multi_match与match类似，不同的是它可以在多个字段中查询。在postman中发起GET请求：http://localhost:9200/user/_search
请求报文为：
{
"query": {
"multi_match": {
"query": "xiaofeng",
"fields": ["name", "nickname"]
}
}
}
响应报文为：
{
"took": 19,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 1,
"relation": "eq"
},
"max_score": 1.3862942,
"hits": [
{
"_index": "user",
"_type": "_doc",
"_id": "102",
"_score": 1.3862942,
"_source": {
"name": "xiaofeng",
"nickname": "帮主",
"sex": "男",
"age": 32
}
}
]
}
}
关键字精确查询
term查询，精确的关键词匹配查询，不对查询条件进行分词。在Postman中发起GET请求：http://localhost:9200/user/_search
请求报文为：
{
"query": {
"term": {
"name": {
"value": "xiaofeng"
}
}
}
}
相应报文为：
{
"took": 4,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 1,
"relation": "eq"
},
"max_score": 1.3862942,
"hits": [
{
"_index": "user",
"_type": "_doc",
"_id": "102",
"_score": 1.3862942,
"_source": {
"name": "xiaofeng",
"nickname": "帮主",
"sex": "男",
"age": 32
}
}
]
}
}
多关键字精确查询
terms查询和term查询一样，不同的是允许指定多值进行匹配，如果这个字段包含了指定值中的任何一个值，那么这个文档满足条件，类似于mysql中的in。在Postman中发起GET请求：http://localhost:9200/user/_search
请求报文为：
{
"query": {
"terms": {
"name": ["xiaofeng", "zhaomin"]
}
}
}
响应报文为：
{
"took": 10,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 2,
"relation": "eq"
},
"max_score": 1.0,
"hits": [
{
"_index": "user",
"_type": "_doc",
"_id": "102",
"_score": 1.0,
"_source": {
"name": "xiaofeng",
"nickname": "帮主",
"sex": "男",
"age": 32
}
},
{
"_index": "user",
"_type": "_doc",
"_id": "103",
"_score": 1.0,
"_source": {
"name": "zhaomin",
"nickname": "郡主",
"sex": "女",
"age": 22
}
}
]
}
}
指定查询字段
通常情况下，ES在搜索结果中会把文档中保存在_source的所有字段都返回，如果只想获取其中的部分字段，可以添加_source过滤。在Postman中发起GET请求：http://localhost:9200/user/_search
请求报文为：
{
"_source": ["name", "nickname"],
"query": {
"terms": {
"name": ["zhangwuji"]
}
}
}
响应报文为：
{
"took": 7,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 1,
"relation": "eq"
},
"max_score": 1.0,
"hits": [
{
"_index": "user",
"_type": "_doc",
"_id": "101",
"_score": 1.0,
"_source": {
"name": "zhangwuji",
"nickname": "教主"
}
}
]
}
}
过滤字段
includes：指定想要显示的字段
excludes：指定不想要显示的字段
在Postman中发起GET请求：http://localhost:9200/user/_search
请求报文为：
{
"_source": {
"includes": ["name", "nickname"]
},
"query": {
"terms": {
"name": ["zhangwuji"]
}
}
}
{
"_source": {
"excludes": ["name", "nickname"]
},
"query": {
"terms": {
"name": ["zhangwuji"]
}
}
}
响应报文为：
{
"took": 6,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 1,
"relation": "eq"
},
"max_score": 1.0,
"hits": [
{
"_index": "user",
"_type": "_doc",
"_id": "101",
"_score": 1.0,
"_source": {
"name": "zhangwuji",
"nickname": "教主"
}
}
]
}
}
{
"took": 5,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 1,
"relation": "eq"
},
"max_score": 1.0,
"hits": [
{
"_index": "user",
"_type": "_doc",
"_id": "101",
"_score": 1.0,
"_source": {
"sex": "男",
"age": 30
}
}
]
}
}
组合查询
bool把各种其他查询通过must、must_not、should的方式进行组合。在Postman中发起GET请求：http://localhost:9200/user/_search
请求报文为：
{
"query": {
"bool": {
"must": [
{
"match": {
"name": "zhangwuji"
}
}
],
"must_not": [
{
"match": {
"age": 40
}
}
],
"should": [
{
"match": {
"sex": "男"
}
}
]
}
}
}
响应报文为：
{
"took": 1006,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 1,
"relation": "eq"
},
"max_score": 2.3754225,
"hits": [
{
"_index": "user",
"_type": "_doc",
"_id": "101",
"_score": 2.3754225,
"_source": {
"name": "zhangwuji",
"nickname": "教主",
"sex": "男",
"age": 30
}
}
]
}
}
范围查询
range查询找出那些落在指定区间内的数字或时间，可以有以下字符
| 操作符 | 说明 |
|---|---|
| gt | 大于> |
| gte | 大于等于>= |
| lt | 小于< |
| lte | 小于等于<= |
在Postman中发起GET请求：http://localhost:9200/user/_search
请求报文为：
{
"query": {
"range": {
"age": {
"gte": 18,
"lte": 40
}
}
}
}
响应报文为：
{
"took": 8,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 5,
"relation": "eq"
},
"max_score": 1.0,
"hits": [
{
"_index": "user",
"_type": "_doc",
"_id": "101",
"_score": 1.0,
"_source": {
"name": "zhangwuji",
"nickname": "教主",
"sex": "男",
"age": 30
}
},
{
"_index": "user",
"_type": "_doc",
"_id": "102",
"_score": 1.0,
"_source": {
"name": "xiaofeng",
"nickname": "帮主",
"sex": "男",
"age": 32
}
},
{
"_index": "user",
"_type": "_doc",
"_id": "103",
"_score": 1.0,
"_source": {
"name": "zhaomin",
"nickname": "郡主",
"sex": "女",
"age": 22
}
},
{
"_index": "user",
"_type": "_doc",
"_id": "104",
"_score": 1.0,
"_source": {
"name": "xiaolongnv",
"nickname": "古墓派",
"sex": "女",
"age": 18
}
},
{
"_index": "user",
"_type": "_doc",
"_id": "105",
"_score": 1.0,
"_source": {
"name": "mafuren",
"nickname": "丐帮夫人",
"sex": "女",
"age": 30
}
}
]
}
}
模糊查询
返回包含于搜索字词相似的字词的文档，编辑距离是将一个术语所需的一个字符更改的次数，包括
更改字符(box -> fox)
删除字符(black -> lack)
插入字符(sic -> sick)
转置两个相邻字符(act->cat)
为了找到相似的术语，fuzzy 查询会在指定的编辑距离内创建一组搜索词的所有可能的变体
或扩展。然后查询返回每个扩展的完全匹配。
通过fuzziness 修改编辑距离。一般使用默认值 AUTO ，根据术语的长度生成编辑距离。
在Postman中，发起GET请求：http://localhost:9200/user/_search
请求报文为：
{
"query": {
"fuzzy": {
"name": {
"value": "zhangwuji"
}
}
}
}
响应报文为：
{
"took": 62,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 1,
"relation": "eq"
},
"max_score": 1.4816045,
"hits": [
{
"_index": "user",
"_type": "_doc",
"_id": "101",
"_score": 1.4816045,
"_source": {
"name": "zhangwuji",
"nickname": "教主",
"sex": "男",
"age": 30
}
}
]
}
}
单字段排序
sort可以按照不同的字段进行排序，通过order指定排序的方式，desc降序，asc升序。在Postman中，发起GET请求：http://localhost:9200/user/_search
请求报文为：
{
"query": {
"match": {
"name": "zhangwuji"
}
},
"sort": [
{
"age": {
"order": "desc"
}
}
]
}
响应报文为：
{
"took": 35,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 1,
"relation": "eq"
},
"max_score": null,
"hits": [
{
"_index": "user",
"_type": "_doc",
"_id": "101",
"_score": null,
"_source": {
"name": "zhangwuji",
"nickname": "教主",
"sex": "男",
"age": 30
},
"sort": [
30
]
}
]
}
}
多字段排序
先按年龄排序，再按相关性得分排序。在Postman中发起GET请求：http://localhost:9200/user/_search
请求报文为：
{
"query": {
"match_all": {
}
},
"sort": [
{
"age": {
"order": "desc"
}
},
{
"_score": {
"order": "desc"
}
}
]
}
响应报文为：
{
"took": 13,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 5,
"relation": "eq"
},
"max_score": null,
"hits": [
{
"_index": "user",
"_type": "_doc",
"_id": "102",
"_score": 1.0,
"_source": {
"name": "xiaofeng",
"nickname": "帮主",
"sex": "男",
"age": 32
},
"sort": [
32,
1.0
]
},
{
"_index": "user",
"_type": "_doc",
"_id": "101",
"_score": 1.0,
"_source": {
"name": "zhangwuji",
"nickname": "教主",
"sex": "男",
"age": 30
},
"sort": [
30,
1.0
]
},
{
"_index": "user",
"_type": "_doc",
"_id": "105",
"_score": 1.0,
"_source": {
"name": "mafuren",
"nickname": "丐帮夫人",
"sex": "女",
"age": 30
},
"sort": [
30,
1.0
]
},
{
"_index": "user",
"_type": "_doc",
"_id": "103",
"_score": 1.0,
"_source": {
"name": "zhaomin",
"nickname": "郡主",
"sex": "女",
"age": 22
},
"sort": [
22,
1.0
]
},
{
"_index": "user",
"_type": "_doc",
"_id": "104",
"_score": 1.0,
"_source": {
"name": "xiaolongnv",
"nickname": "古墓派",
"sex": "女",
"age": 18
},
"sort": [
18,
1.0
]
}
]
}
}
高亮查询
进行关键字搜索时，搜索出的内容中的关键字会显示不同的颜色，称为高亮。
在ES中可以对查询内容中的关键字部分进行标签和样式(高亮)的设置，在使用match查询的同时，加上highlight属性
pre_tags：前置标签
post_tags：后置标签
fields：需要高亮的字段
在Postman中发起GET请求：http://localhost:9200/user/_search
请求报文为：
{
"query": {
"match": {
"name": "zhangwuji"
}
},
"highlight": {
"pre_tags": "<font color='red'>",
"post_tags": "</font>",
"fields": {
"name": {
}
}
}
}
响应报文为：
{
"took": 62,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 1,
"relation": "eq"
},
"max_score": 1.3862942,
"hits": [
{
"_index": "user",
"_type": "_doc",
"_id": "101",
"_score": 1.3862942,
"_source": {
"name": "zhangwuji",
"nickname": "教主",
"sex": "男",
"age": 30
},
"highlight": {
"name": [
"<font color='red'>zhangwuji</font>"
]
}
}
]
}
}
分页查询
from：当前页的起始索引，默认从0开始。from = (pageNum – 1) * size
size：每页显示多少条
在Postman中，发起GET请求：http://localhost:9200/user/_search
请求报文为：
{
"query": {
"match_all": {
}
},
"sort": [
{
"age": {
"order": "desc"
}
}
],
"from": 0,
"size": 2
}
响应报文为：
{
"took": 6,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 5,
"relation": "eq"
},
"max_score": null,
"hits": [
{
"_index": "user",
"_type": "_doc",
"_id": "102",
"_score": null,
"_source": {
"name": "xiaofeng",
"nickname": "帮主",
"sex": "男",
"age": 32
},
"sort": [
32
]
},
{
"_index": "user",
"_type": "_doc",
"_id": "101",
"_score": null,
"_source": {
"name": "zhangwuji",
"nickname": "教主",
"sex": "男",
"age": 30
},
"sort": [
30
]
}
]
}
}
聚合查询
用于对ES文档进行统计分析
取最大值-max
在Postman中发起GET请求：http://localhost:9200/user/_search
请求报文为：
{
"aggs": {
"max_age": {
"max": {
"field": "age"
}
}
},
"size": 0
}
响应报文为：
{
"took": 48,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 5,
"relation": "eq"
},
"max_score": null,
"hits": []
},
"aggregations": {
"max_age": {
"value": 32.0
}
}
}
取最小值-min
在Postman中发起GET请求：http://localhost:9200/user/_search
请求报文为：
{
"aggs": {
"min_age": {
"min": {
"field": "age"
}
}
},
"size": 0
}
响应报文为：
{
"took": 5,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 5,
"relation": "eq"
},
"max_score": null,
"hits": []
},
"aggregations": {
"min_age": {
"value": 18.0
}
}
}
求和-sum
在Postman中发起GET请求：http://localhost:9200/user/_search
请求报文为：
{
"aggs": {
"sum_age": {
"sum": {
"field": "age"
}
}
},
"size": 0
}
响应报文为：
{
"took": 13,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 5,
"relation": "eq"
},
"max_score": null,
"hits": []
},
"aggregations": {
"sum_age": {
"value": 132.0
}
}
}
取平均值-avg
在Postman中发起GET请求：http://localhost:9200/user/_search
请求报文为：
{
"aggs": {
"avg_age": {
"avg": {
"field": "age"
}
}
},
"size": 0
}
响应报文为：
{
"took": 4,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 5,
"relation": "eq"
},
"max_score": null,
"hits": []
},
"aggregations": {
"avg_age": {
"value": 26.4
}
}
}
去重后取总数
在Postman中发起GET请求：http://localhost:9200/user/_search
请求报文为：
{
"aggs": {
"distinct_age": {
"cardinality": {
"field": "age"
}
}
},
"size": 0
}
响应报文为：
{
"took": 27,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 5,
"relation": "eq"
},
"max_score": null,
"hits": []
},
"aggregations": {
"distinct_age": {
"value": 4
}
}
}
State聚合
对某个字段一次性返回count，max，min，avg和sum
在Postman中发起GET请求：http://localhost:9200/user/_search
请求报文为：
{
"aggs": {
"stats_age": {
"stats": {
"field": "age"
}
}
},
"size": 0
}
响应报文为：
{
"took": 6,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 5,
"relation": "eq"
},
"max_score": null,
"hits": []
},
"aggregations": {
"stats_age": {
"count": 5,
"min": 18.0,
"max": 32.0,
"avg": 26.4,
"sum": 132.0
}
}
}
桶聚合查询
相当于sql中的group by
terms聚合，分组统计
在Postman中发起GET请求：http://localhost:9200/user/_search
请求报文为：
{
"aggs": {
"age_groupby": {
"terms": {
"field": "age"
}
}
},
"size": 0
}
响应报文为：
{
"took": 28,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 5,
"relation": "eq"
},
"max_score": null,
"hits": []
},
"aggregations": {
"age_groupby": {
"doc_count_error_upper_bound": 0,
"sum_other_doc_count": 0,
"buckets": [
{
"key": 30,
"doc_count": 2
},
{
"key": 18,
"doc_count": 1
},
{
"key": 22,
"doc_count": 1
},
{
"key": 32,
"doc_count": 1
}
]
}
}
}
在terms分组下再进行聚合
在Postman中发起GET请求：http://localhost:9200/user/_search
请求报文为：
{
"aggs": {
"age_groupby": {
"terms": {
"field": "age"
},
"aggs": {
"sum_age": {
"sum": {
"field": "age"
}
}
}
}
},
"size": 0
}
响应报文为：
{
"took": 8,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 5,
"relation": "eq"
},
"max_score": null,
"hits": []
},
"aggregations": {
"age_groupby": {
"doc_count_error_upper_bound": 0,
"sum_other_doc_count": 0,
"buckets": [
{
"key": 30,
"doc_count": 2,
"sum_age": {
"value": 60.0
}
},
{
"key": 18,
"doc_count": 1,
"sum_age": {
"value": 18.0
}
},
{
"key": 22,
"doc_count": 1,
"sum_age": {
"value": 22.0
}
},
{
"key": 32,
"doc_count": 1,
"sum_age": {
"value": 32.0
}
}
]
}
}
}
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