Elasticsearch入门
环境准备
下载使用7.8版本:https://www.elastic.co/cn/downloads/past-releases/elasticsearch-7-8-0
解压后,进入 bin 文件目录,点击 elasticsearch.bat 文件启动 ES 服务 。
注意: 9300 端口为 Elasticsearch 集群间组件的通信端口, 9200 端口为浏览器访问的 http协议 RESTful 端口。
打开浏览器,输入地址: http://localhost:9200, 测试返回结果,返回结果如下:
RESTful & JSON
REST 指的是一组架构约束条件和原则。满足这些约束条件和原则的应用程序或设计就是 RESTful。 Web 应用程序最重要的 REST 原则是,客户端和服务器之间的交互在请求之间是无状态的。从客户端到服务器的每个请求都必须包含理解请求所必需的信息。如果服务器在请求之间的任何时间点重启,客户端不会得到通知。此外,无状态请求可以由任何可用服务器回答,这十分适合云计算之类的环境。客户端可以缓存数据以改进性能。
在服务器端,应用程序状态和功能可以分为各种资源。资源是一个有趣的概念实体,它向客户端公开。资源的例子有:应用程序对象、数据库记录、算法等等。每个资源都使用 URI(Universal Resource Identifier) 得到一个唯一的地址。所有资源都共享统一的接口,以便在客户端和服务器之间传输状态。使用的是标准的 HTTP 方法,比如 GET、 PUT、 POST 和DELETE。
在 REST 样式的 Web 服务中,每个资源都有一个地址。资源本身都是方法调用的目
标,方法列表对所有资源都是一样的。这些方法都是标准方法,包括 HTTP GET、 POST、PUT、 DELETE,还可能包括 HEAD 和 OPTIONS。简单的理解就是,如果想要访问互联网上的资源,就必须向资源所在的服务器发出请求,请求体中必须包含资源的网络路径, 以及对资源进行的操作(增删改查)。
REST 样式的 Web 服务若有返回结果,大多数以JSON字符串形式返回。
倒排索引
-
正排索引(传统)
|id |content|
|----|----|
|1001 |my name is zhang san|
|1002 |my name is li si| -
倒排索引
|keyword |id|
|----|----|
|name |1001, 1002|
|zhang |1001|
Elasticsearch 是面向文档型数据库,一条数据在这里就是一个文档。 为了方便大家理解,我们将 Elasticsearch 里存储文档数据和关系型数据库 MySQL 存储数据的概念进行一个类比
ES 里的 Index 可以看做一个库,而 Types 相当于表, Documents 则相当于表的行。这里 Types 的概念已经被逐渐弱化, Elasticsearch 6.X 中,一个 index 下已经只能包含一个type, Elasticsearch 7.X 中, Type 的概念已经被删除了。
HTTP-索引-创建
对比关系型数据库,创建索引就等同于创建数据库。
在 Postman 中,向 ES 服务器发 PUT 请求 : http://127.0.0.1:9200/shopping 等于意思就是创建一个名叫shopping 的索引
请求后,服务器返回响应:
因为已经创建成功,如果再次请求,会报错已经存在
如果换post请求,也会报错不允许post请求
HTTP-索引-查询 & 删除
查询指定索引
使用GET 方式请求http://127.0.0.1:9200/shopping
查看所有索引
在 Postman 中,向 ES 服务器发 GET 请求 : http://127.0.0.1:9200/_cat/indices?v
这里请求路径中的_cat 表示查看的意思, indices 表示索引,所以整体含义就是查看当前 ES服务器中的所有索引,就好像 MySQL 中的 show tables 的感觉,服务器响应结果如下 :
表头 | 含义 |
---|---|
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 |
删除索引
在 Postman 中,向 ES 服务器发 DELETE 请求 : http://127.0.0.1:9200/shopping
删除后在查询所有索引,发现已经没有索引了
HTTP-文档-创建(Put & Post)
假设索引已经创建好了,接下来我们来创建文档,并添加数据。这里的文档可以类比为关系型数据库中的表数据,添加的数据格式为 JSON 格式
在 Postman 中,向 ES 服务器发 POST 请求 : http://127.0.0.1:9200/shopping/_doc 请求体JSON内容为:
如果再次请求,就会再次有新的索引id,多次请求是不一样的,因为POST 请求方式没有要求幂等性,但是PUT 请求必须是幂等性的,所以使用PUT请求就会报错
自定义主键id
自定义唯一性标识,需要在创建时指定: http://127.0.0.1:9200/shopping/_doc/1001
那么创建成功后的文档索引就是1001
既然是自定义的,那就算是幂等性的,所以自定义主键时创建文档可以使用PUT 方式请求
因为是创建,所以把请求路径中的_doc 改成_create 也行
HTTP-查询-主键查询 & 全查询
查看文档时,需要指明文档的唯一性标识,类似于 MySQL 中数据的主键查询
在 Postman 中,向 ES 服务器发 GET 请求 : http://127.0.0.1:9200/shopping/_doc/1001
如果查找不存在的数据:http://127.0.0.1:9200/shopping/_doc/2001 2001这个之前没有创建过,所以肯定没有的
查询所有数据
同样使用GET 请求,请求路径修改问:http://127.0.0.1:9200/shopping/_search
就可以把所有数据都给查询到
HTTP-全量修改 & 局部修改 & 删除
全量修改
和新增文档一样,输入相同的 URL 地址请求,如果请求体变化,会将原有的数据内容覆盖
在 Postman 中,向 ES 服务器发 PUT 请求 : http://127.0.0.1:9200/shopping/_doc/1001
请求时候可以自定义修改文档数据内容
然后查询,GET 请求:http://127.0.0.1:9200/shopping/_doc/1001
说明确实修改成功
局部修改
修改数据时,也可以只修改某一给条数据的局部信息
在 Postman 中,向 ES 服务器发 POST 请求 : http://127.0.0.1:9200/shopping/_update/1001
求情路径把_doc 改为_update 表示为修改,以免以为是添加数据
然后请求的body 稍微修改一下
查询验证是否修改,GET 请求查询:http://127.0.0.1:9200/shopping/_doc/1001
删除
DELETE 请求:http://127.0.0.1:9200/shopping/_doc/1001
如果再次删除1001主键的数据,会提示找不到,因为数据已经删了,没有了
HTTP-条件查询 & 分页查询 & 查询排序
条件查询
假设有以下文档内容,在 Postman 中,向 ES 服务器发 GET请求 : http://127.0.0.1:9200/shopping/_search
分页查询
发 GET请求 : http://127.0.0.1:9200/shopping/_search
如果不想查找所有数据,只想查找title 的数据,修改请求体
查询排序
如果你想通过排序查出价格最高的手机,在 Postman 中,向 ES 服务器发 GET请求 : http://127.0.0.1:9200/shopping/_search
HTTP-多条件查询 & 范围查询
多条件查询
假设想找出小米牌子,价格为3999元的。must相当于数据库的&&
在 Postman 中,向 ES 服务器发 GET请求 : http://127.0.0.1:9200/shopping/_search 附带JSON体如下:
假设想找出小米和华为的牌子。should相当于数据库的||
在 Postman 中,向 ES 服务器发 GET请求 : http://127.0.0.1:9200/shopping/_search 附带JSON体如下
范围查询
假设想找出小米和华为的牌子,价格大于2000元的手机。
在 Postman 中,向 ES 服务器发 GET请求 : http://127.0.0.1:9200/shopping/_search 附带JSON体如下:
HTTP-全文检索 & 完全匹配 & 高亮查询
全文检索
这功能像搜索引擎那样,如品牌输入“小华”,返回结果带回品牌有“小米”和华为的。
在 Postman 中,向 ES 服务器发 GET请求 : http://127.0.0.1:9200/shopping/_search 附带JSON体如下:
完全匹配
在 Postman 中,向 ES 服务器发 GET请求 : http://127.0.0.1:9200/shopping/_search 附带JSON体如下
这次写“小华” 就不行了,必须要是完全匹配才行
高亮查询
在 Postman 中,向 ES 服务器发 GET请求 : http://127.0.0.1:9200/shopping/_search 附带JSON体如下:
HTTP-聚合查询
聚合允许使用者对 es 文档进行统计分析,类似与关系型数据库中的 group by,当然还有很多其他的聚合,例如取最大值max、平均值avg等等。
接下来按price字段进行分组:
在 Postman 中,向 ES 服务器发 GET请求 : http://127.0.0.1:9200/shopping/_search 附带JSON体如下:
上面返回结果会附带原始数据的。若不想要不附带原始数据的结果,修改请求体:
{
"aggs":{
"price_group":{
"terms":{
"field":"price"
}
}
},
"size":0
}
若想对所有手机价格求平均值,修改请求体:
{
"aggs":{
"price_avg":{//名称,随意起名
"avg":{//求平均
"field":"price"
}
}
},
"size":0
}
HTTP-映射关系
有了索引库,等于有了数据库中的 database。
接下来就需要建索引库(index)中的映射了,类似于数据库(database)中的表结构(table)。
创建数据库表需要设置字段名称,类型,长度,约束等;索引库也一样,需要知道这个类型下有哪些字段,每个字段有哪些约束信息,这就叫做映射(mapping)。
先创建一个索引:PUT 请求:http://127.0.0.1:9200/user
创建映射:PUT 请求:http://127.0.0.1:9200/user/_mapping
然后使用GET 请求查询,可以查出来的
然后开始添加测试数据
查找name含有”小“数据:GET 请求:http://127.0.0.1:9200/user/_search
查找sex含有”男“数据:GET 请求: http://127.0.0.1:9200/user/_search
找不想要的结果,只因创建映射时"sex"的类型为"keyword"。
"sex"只能完全为”男的“,才能得出原数据。
修改请求体,改成"男的"
查询电话,修改请求体
报错只因创建映射时"tel"的"index"为false。
入门-JavaAPI
环境准备
新建Maven工程。
添加依赖:
<dependencies>
<dependency>
<groupId>org.elasticsearch</groupId>
<artifactId>elasticsearch</artifactId>
<version>7.8.0</version>
</dependency>
<!-- elasticsearch 的客户端 -->
<dependency>
<groupId>org.elasticsearch.client</groupId>
<artifactId>elasticsearch-rest-high-level-client</artifactId>
<version>7.8.0</version>
</dependency>
<!-- elasticsearch 依赖 2.x 的 log4j -->
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-api</artifactId>
<version>2.8.2</version>
</dependency>
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-core</artifactId>
<version>2.8.2</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.9.9</version>
</dependency>
<!-- junit 单元测试 -->
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
</dependency>
</dependencies>
创建测试类:
import java.io.IOException;
import org.apache.http.HttpHost;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
public class HelloElasticsearch {
public static void main(String[] args) throws IOException {
// 创建客户端对象
RestHighLevelClient client = new RestHighLevelClient(
RestClient.builder(new HttpHost("localhost", 9200, "http"))
);
// ...
System.out.println(client);
// 关闭客户端连接
client.close();
}
}
如果允许没有报错,就说明是没问题的
索引
创建
创建测试类:
import org.apache.http.HttpHost;
import org.elasticsearch.action.admin.indices.create.CreateIndexRequest;
import org.elasticsearch.action.admin.indices.create.CreateIndexResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import java.io.IOException;
public class CreateIndex {
public static void main(String[] args) throws IOException {
// 创建客户端对象
RestHighLevelClient client = new RestHighLevelClient(
RestClient.builder(new HttpHost("localhost", 9200, "http"))
);
// 创建索引 - 请求对象
CreateIndexRequest request = new CreateIndexRequest("user2");
// 发送请求,获取响应
CreateIndexResponse response = client.indices().create(request, RequestOptions.DEFAULT);
boolean acknowledged = response.isAcknowledged();
// 响应状态
System.out.println("操作状态 = " + acknowledged);
// 关闭客户端连接
client.close();
}
}
控制台打印结果为:true,说明成功,可以使用postman 发送GET 请求:http://127.0.0.1:9200/_cat/indices?v 查看
查询 & 删除
查询
测试类:
import org.apache.http.HttpHost;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.client.indices.GetIndexRequest;
import org.elasticsearch.client.indices.GetIndexResponse;
import java.io.IOException;
public class SearchIndex {
public static void main(String[] args) throws IOException {
// 创建客户端对象
RestHighLevelClient client = new RestHighLevelClient(
RestClient.builder(new HttpHost("localhost", 9200, "http"))
);
// 查询索引 - 请求对象
GetIndexRequest request = new GetIndexRequest("user2");
// 发送请求,获取响应
GetIndexResponse response = client.indices().get(request, RequestOptions.DEFAULT);
System.out.println("aliases:" + response.getAliases());
System.out.println("mappings:" + response.getMappings());
System.out.println("settings:" + response.getSettings());
client.close();
}
}
控制台打印:
删除
测试类:
import org.apache.http.HttpHost;
import org.elasticsearch.action.admin.indices.delete.DeleteIndexRequest;
import org.elasticsearch.action.support.master.AcknowledgedResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import java.io.IOException;
public class DeleteIndex {
public static void main(String[] args) throws IOException {
RestHighLevelClient client = new RestHighLevelClient(
RestClient.builder(new HttpHost("localhost", 9200, "http"))
);
// 删除索引 - 请求对象
DeleteIndexRequest request = new DeleteIndexRequest("user2");
// 发送请求,获取响应
AcknowledgedResponse response = client.indices().delete(request, RequestOptions.DEFAULT);
// 操作结果
System.out.println("操作结果 : " + response.isAcknowledged());
client.close();
}
}
控制台打印返回结果为true, 说明删除操作成功
文档
新增 & 修改
创建对象user
import lombok.Data;
@Data
public class User {
private String name;
private String sex;
private Integer age;
}
新增
import com.fasterxml.jackson.databind.ObjectMapper;
import org.apache.http.HttpHost;
import org.elasticsearch.action.index.IndexRequest;
import org.elasticsearch.action.index.IndexResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.common.xcontent.XContentType;
import java.io.IOException;
public class InsertDoc {
public static void main(String[] args) throws IOException {
// 创建客户端对象
RestHighLevelClient client = new RestHighLevelClient(
RestClient.builder(new HttpHost("localhost", 9200, "http"))
);
// 新增文档 - 请求对象
IndexRequest request = new IndexRequest();
// 设置索引及唯一性标识
request.index("user").id("1001");
// 创建数据对象
User user = new User();
user.setName("zhangsan");
user.setAge(30);
user.setSex("男");
ObjectMapper objectMapper = new ObjectMapper();
String productJson = objectMapper.writeValueAsString(user);
// 添加文档数据,数据格式为 JSON 格式
request.source(productJson, XContentType.JSON);
// 客户端发送请求,获取响应对象
IndexResponse response = client.index(request, RequestOptions.DEFAULT);
// 打印结果信息
System.out.println("_index:" + response.getIndex());
System.out.println("_id:" + response.getId());
System.out.println("_result:" + response.getResult());
client.close();
}
}
控制台打印:
修改
import org.apache.http.HttpHost;
import org.elasticsearch.action.update.UpdateRequest;
import org.elasticsearch.action.update.UpdateResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.common.xcontent.XContentType;
import java.io.IOException;
public class UpdateDoc {
public static void main(String[] args) throws IOException {
// 创建客户端对象
RestHighLevelClient client = new RestHighLevelClient(
RestClient.builder(new HttpHost("localhost", 9200, "http"))
);
// 新增文档 - 请求对象
UpdateRequest request = new UpdateRequest();
request.index("user").id("1001");
request.doc(XContentType.JSON, "sex", "女");
UpdateResponse response = client.update(request, RequestOptions.DEFAULT);
// 打印结果信息
System.out.println(response.getResult());
client.close();
}
}
允许后,查看是否修改成功,postman 发送GET 请求:http://127.0.0.1:9200/user/_doc/1001
查询 & 删除
查询
import org.apache.http.HttpHost;
import org.elasticsearch.action.get.GetRequest;
import org.elasticsearch.action.get.GetResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import java.io.IOException;
public class GetDoc {
public static void main(String[] args) throws IOException {
// 创建客户端对象
RestHighLevelClient client = new RestHighLevelClient(
RestClient.builder(new HttpHost("localhost", 9200, "http"))
);
//1.创建请求对象
GetRequest request = new GetRequest().index("user").id("1001");
//2.客户端发送请求,获取响应对象
GetResponse response = client.get(request, RequestOptions.DEFAULT);
//3.打印结果信息
System.out.println("source:" + response.getSourceAsString());
client.close();
}
}
运行后查看控制台:
删除
import org.apache.http.HttpHost;
import org.elasticsearch.action.delete.DeleteRequest;
import org.elasticsearch.action.delete.DeleteResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import java.io.IOException;
public class DeleteDoc {
public static void main(String[] args) throws IOException {
// 创建客户端对象
RestHighLevelClient client = new RestHighLevelClient(
RestClient.builder(new HttpHost("localhost", 9200, "http"))
);
//创建请求对象
DeleteRequest request = new DeleteRequest().index("user").id("1001");
//客户端发送请求,获取响应对象
DeleteResponse response = client.delete(request, RequestOptions.DEFAULT);
//打印信息
System.out.println(response.toString());
client.close();
}
}
执行后,确实查不到了
批量新增 & 批量删除
批量新增
import org.apache.http.HttpHost;
import org.elasticsearch.action.bulk.BulkRequest;
import org.elasticsearch.action.bulk.BulkResponse;
import org.elasticsearch.action.index.IndexRequest;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.common.xcontent.XContentType;
import java.io.IOException;
public class BatchInsertDoc {
public static void main(String[] args) throws IOException {
// 创建客户端对象
RestHighLevelClient client = new RestHighLevelClient(
RestClient.builder(new HttpHost("localhost", 9200, "http"))
);
//创建批量新增请求对象
BulkRequest request = new BulkRequest();
request.add(new IndexRequest().index("user").id("1001").source(XContentType.JSON, "name", "zhangsan"));
request.add(new IndexRequest().index("user").id("1002").source(XContentType.JSON, "name", "lisi"));
request.add(new IndexRequest().index("user").id("1003").source(XContentType.JSON, "name", "wangwu"));
//客户端发送请求,获取响应对象
BulkResponse responses = client.bulk(request, RequestOptions.DEFAULT);
//打印结果信息
System.out.println("took:" + responses.getTook());
System.out.println("items:" + responses.getItems());
client.close();
}
}
批量删除
import org.apache.http.HttpHost;
import org.elasticsearch.action.bulk.BulkRequest;
import org.elasticsearch.action.bulk.BulkResponse;
import org.elasticsearch.action.delete.DeleteRequest;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import java.io.IOException;
public class BatchDeleteDoc {
public static void main(String[] args) throws IOException {
// 创建客户端对象
RestHighLevelClient client = new RestHighLevelClient(
RestClient.builder(new HttpHost("localhost", 9200, "http"))
);
//创建批量删除请求对象
BulkRequest request = new BulkRequest();
request.add(new DeleteRequest().index("user").id("1001"));
request.add(new DeleteRequest().index("user").id("1002"));
request.add(new DeleteRequest().index("user").id("1003"));
//客户端发送请求,获取响应对象
BulkResponse responses = client.bulk(request, RequestOptions.DEFAULT);
//打印结果信息
System.out.println("took:" + responses.getTook());
System.out.println("items:" + responses.getItems());
client.close();
}
}
高级查询
全量查询
先批量增加数据:
import org.apache.http.HttpHost;
import org.elasticsearch.action.bulk.BulkRequest;
import org.elasticsearch.action.bulk.BulkResponse;
import org.elasticsearch.action.index.IndexRequest;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.common.xcontent.XContentType;
import java.io.IOException;
public class BatchInsertDoc {
public static void main(String[] args) throws IOException {
// 创建客户端对象
RestHighLevelClient client = new RestHighLevelClient(
RestClient.builder(new HttpHost("localhost", 9200, "http"))
);
//创建批量新增请求对象
BulkRequest request = new BulkRequest();
request.add(new IndexRequest().index("user").id("1001").source(XContentType.JSON, "name", "zhangsan", "age", "10", "sex", "女"));
request.add(new IndexRequest().index("user").id("1002").source(XContentType.JSON, "name", "lisi", "age", "30", "sex", "女"));
request.add(new IndexRequest().index("user").id("1003").source(XContentType.JSON, "name", "wangwu1", "age", "40", "sex", "男"));
request.add(new IndexRequest().index("user").id("1004").source(XContentType.JSON, "name", "wangwu2", "age", "20", "sex", "女"));
request.add(new IndexRequest().index("user").id("1005").source(XContentType.JSON, "name", "wangwu3", "age", "50", "sex", "男"));
request.add(new IndexRequest().index("user").id("1006").source(XContentType.JSON, "name", "wangwu4", "age", "20", "sex", "男"));
BulkResponse responses = client.bulk(request, RequestOptions.DEFAULT);
//打印结果信息
System.out.println("took:" + responses.getTook());
System.out.println("items:" + responses.getItems());
client.close();
}
}
查询所有索引数据
import org.apache.http.HttpHost;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import java.io.IOException;
public class QueryDoc {
public static void main(String[] args) throws IOException {
// 创建客户端对象
RestHighLevelClient client = new RestHighLevelClient(
RestClient.builder(new HttpHost("localhost", 9200, "http"))
);
// 创建搜索请求对象
SearchRequest request = new SearchRequest();
request.indices("user");
// 构建查询的请求体
SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
// 查询所有数据
sourceBuilder.query(QueryBuilders.matchAllQuery());
request.source(sourceBuilder);
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
// 查询匹配
SearchHits hits = response.getHits();
System.out.println("took:" + response.getTook());
System.out.println("timeout:" + response.isTimedOut());
System.out.println("total:" + hits.getTotalHits());
System.out.println("MaxScore:" + hits.getMaxScore());
System.out.println("hits========>>");
for (SearchHit hit : hits) {
//输出每条查询的结果信息
System.out.println(hit.getSourceAsString());
}
System.out.println("<<========");
client.close();
}
}
控制台打印:
分页查询 & 条件查询 & 查询排序
条件查询
找出年龄30岁的
import org.apache.http.HttpHost;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import java.io.IOException;
public class ConditionQueryDoc {
public static void main(String[] args) throws IOException {
// 创建客户端对象
RestHighLevelClient client = new RestHighLevelClient(
RestClient.builder(new HttpHost("localhost", 9200, "http"))
);
// 创建搜索请求对象
SearchRequest request = new SearchRequest();
request.indices("user");
// 构建查询的请求体
SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
sourceBuilder.query(QueryBuilders.termQuery("age", "30"));
request.source(sourceBuilder);
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
// 查询匹配
SearchHits hits = response.getHits();
System.out.println("took:" + response.getTook());
System.out.println("timeout:" + response.isTimedOut());
System.out.println("total:" + hits.getTotalHits());
System.out.println("MaxScore:" + hits.getMaxScore());
System.out.println("hits========>>");
for (SearchHit hit : hits) {
//输出每条查询的结果信息
System.out.println(hit.getSourceAsString());
}
System.out.println("<<========");
client.close();
}
}
控制台输出:
分页查询
第0页,每页显示2条
import org.apache.http.HttpHost;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import java.io.IOException;
public class PagingQueryDoc {
public static void main(String[] args) throws IOException {
// 创建客户端对象
RestHighLevelClient client = new RestHighLevelClient(
RestClient.builder(new HttpHost("localhost", 9200, "http"))
);
// 创建搜索请求对象
SearchRequest request = new SearchRequest();
request.indices("user");
// 构建查询的请求体
SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
sourceBuilder.query(QueryBuilders.matchAllQuery());
// 分页查询
// 当前页其实索引(第一条数据的顺序号), from
sourceBuilder.from(0);
// 每页显示多少条 size
sourceBuilder.size(2);
request.source(sourceBuilder);
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
// 查询匹配
SearchHits hits = response.getHits();
System.out.println("took:" + response.getTook());
System.out.println("timeout:" + response.isTimedOut());
System.out.println("total:" + hits.getTotalHits());
System.out.println("MaxScore:" + hits.getMaxScore());
System.out.println("hits========>>");
for (SearchHit hit : hits) {
//输出每条查询的结果信息
System.out.println(hit.getSourceAsString());
}
System.out.println("<<========");
client.close();
}
}
控制台打印:
查询排序
根据年龄排序
import org.apache.http.HttpHost;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import org.elasticsearch.search.sort.SortOrder;
import java.io.IOException;
public class SortQueryDoc {
public static void main(String[] args) throws IOException {
// 创建客户端对象
RestHighLevelClient client = new RestHighLevelClient(
RestClient.builder(new HttpHost("localhost", 9200, "http"))
);
// 创建搜索请求对象
SearchRequest request = new SearchRequest();
request.indices("user");
// 构建查询的请求体
SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
sourceBuilder.query(QueryBuilders.matchAllQuery());
// 排序
sourceBuilder.sort("age", SortOrder.ASC);
request.source(sourceBuilder);
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
// 查询匹配
SearchHits hits = response.getHits();
System.out.println("took:" + response.getTook());
System.out.println("timeout:" + response.isTimedOut());
System.out.println("total:" + hits.getTotalHits());
System.out.println("MaxScore:" + hits.getMaxScore());
System.out.println("hits========>>");
for (SearchHit hit : hits) {
//输出每条查询的结果信息
System.out.println(hit.getSourceAsString());
}
System.out.println("<<========");
client.close();
}
}
控制台打印:
组合查询 & 范围查询
组合查询
import org.apache.http.HttpHost;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.index.query.BoolQueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import java.io.IOException;
public class CombinationQueryDoc {
public static void main(String[] args) throws IOException {
// 创建客户端对象
RestHighLevelClient client = new RestHighLevelClient(
RestClient.builder(new HttpHost("localhost", 9200, "http"))
);
// 创建搜索请求对象
SearchRequest request = new SearchRequest();
request.indices("user");
// 构建查询的请求体
SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
BoolQueryBuilder boolQueryBuilder = QueryBuilders.boolQuery();
// 必须包含
boolQueryBuilder.must(QueryBuilders.matchQuery("age", "30"));
// 一定不含
boolQueryBuilder.mustNot(QueryBuilders.matchQuery("name", "zhangsan"));
// 可能包含
boolQueryBuilder.should(QueryBuilders.matchQuery("sex", "男"));
sourceBuilder.query(boolQueryBuilder);
request.source(sourceBuilder);
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
// 查询匹配
SearchHits hits = response.getHits();
System.out.println("took:" + response.getTook());
System.out.println("timeout:" + response.isTimedOut());
System.out.println("total:" + hits.getTotalHits());
System.out.println("MaxScore:" + hits.getMaxScore());
System.out.println("hits========>>");
for (SearchHit hit : hits) {
//输出每条查询的结果信息
System.out.println(hit.getSourceAsString());
}
System.out.println("<<========");
client.close();
}
}
控制台打印:
范围查询
import org.apache.http.HttpHost;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.query.RangeQueryBuilder;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import java.io.IOException;
public class ScopeQueryDoc {
public static void main(String[] args) throws IOException {
// 创建客户端对象
RestHighLevelClient client = new RestHighLevelClient(
RestClient.builder(new HttpHost("localhost", 9200, "http"))
);
// 创建搜索请求对象
SearchRequest request = new SearchRequest();
request.indices("user");
// 构建查询的请求体
SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
RangeQueryBuilder rangeQuery = QueryBuilders.rangeQuery("age");
// 大于等于
//rangeQuery.gte("30");
// 小于等于
rangeQuery.lte("40");
sourceBuilder.query(rangeQuery);
request.source(sourceBuilder);
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
// 查询匹配
SearchHits hits = response.getHits();
System.out.println("took:" + response.getTook());
System.out.println("timeout:" + response.isTimedOut());
System.out.println("total:" + hits.getTotalHits());
System.out.println("MaxScore:" + hits.getMaxScore());
System.out.println("hits========>>");
for (SearchHit hit : hits) {
//输出每条查询的结果信息
System.out.println(hit.getSourceAsString());
}
System.out.println("<<========");
client.close();
}
}
控制台打印:
模糊查询 & 高亮查询
模糊查询
import org.apache.http.HttpHost;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.common.unit.Fuzziness;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import java.io.IOException;
public class DimQueryDoc {
public static void main(String[] args) throws IOException {
// 创建客户端对象
RestHighLevelClient client = new RestHighLevelClient(
RestClient.builder(new HttpHost("localhost", 9200, "http"))
);
// 创建搜索请求对象
SearchRequest request = new SearchRequest();
request.indices("user");
// 构建查询的请求体
SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
sourceBuilder.query(QueryBuilders.fuzzyQuery("name","wangwu").fuzziness(Fuzziness.ONE));
request.source(sourceBuilder);
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
// 查询匹配
SearchHits hits = response.getHits();
System.out.println("took:" + response.getTook());
System.out.println("timeout:" + response.isTimedOut());
System.out.println("total:" + hits.getTotalHits());
System.out.println("MaxScore:" + hits.getMaxScore());
System.out.println("hits========>>");
for (SearchHit hit : hits) {
//输出每条查询的结果信息
System.out.println(hit.getSourceAsString());
}
System.out.println("<<========");
client.close();
}
}
控制台打印:
高亮查询
import org.apache.http.HttpHost;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.query.TermsQueryBuilder;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightField;
import java.io.IOException;
import java.util.Map;
public class HighilghtQueryDoc {
public static void main(String[] args) throws IOException {
// 创建客户端对象
RestHighLevelClient client = new RestHighLevelClient(
RestClient.builder(new HttpHost("localhost", 9200, "http"))
);
// 高亮查询
SearchRequest request = new SearchRequest().indices("user");
//2.创建查询请求体构建器
SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
//构建查询方式:高亮查询
TermsQueryBuilder termsQueryBuilder = QueryBuilders.termsQuery("name", "zhangsan");
//设置查询方式
sourceBuilder.query(termsQueryBuilder);
//构建高亮字段
HighlightBuilder highlightBuilder = new HighlightBuilder();
highlightBuilder.preTags("<font color='red'>");//设置标签前缀
highlightBuilder.postTags("</font>");//设置标签后缀
highlightBuilder.field("name");//设置高亮字段
//设置高亮构建对象
sourceBuilder.highlighter(highlightBuilder);
//设置请求体
request.source(sourceBuilder);
//3.客户端发送请求,获取响应对象
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4.打印响应结果
SearchHits hits = response.getHits();
System.out.println("took::" + response.getTook());
System.out.println("time_out::" + response.isTimedOut());
System.out.println("total::" + hits.getTotalHits());
System.out.println("max_score::" + hits.getMaxScore());
System.out.println("hits::::>>");
for (SearchHit hit : hits) {
String sourceAsString = hit.getSourceAsString();
System.out.println(sourceAsString);
//打印高亮结果
Map<String, HighlightField> highlightFields = hit.getHighlightFields();
System.out.println(highlightFields);
}
System.out.println("<<::::");
client.close();
}
}
控制台打印:
最大值查询 & 分组查询
最大值查询
import org.apache.http.HttpHost;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.aggregations.AggregationBuilders;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import java.io.IOException;
public class MaximumValueQueryDoc {
public static void main(String[] args) throws IOException {
// 创建客户端对象
RestHighLevelClient client = new RestHighLevelClient(
RestClient.builder(new HttpHost("localhost", 9200, "http"))
);
SearchRequest request = new SearchRequest().indices("user");
SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
sourceBuilder.aggregation(AggregationBuilders.max("maxAge").field("age"));
//设置请求体
request.source(sourceBuilder);
//3.客户端发送请求,获取响应对象
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4.打印响应结果
SearchHits hits = response.getHits();
System.out.println(response);
client.close();
}
}
分组查询
import org.apache.http.HttpHost;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.aggregations.AggregationBuilders;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import java.io.IOException;
public class GroupingQueryDoc {
public static void main(String[] args) throws IOException {
// 创建客户端对象
RestHighLevelClient client = new RestHighLevelClient(
RestClient.builder(new HttpHost("localhost", 9200, "http"))
);
SearchRequest request = new SearchRequest().indices("user");
SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
sourceBuilder.aggregation(AggregationBuilders.terms("age_groupby").field("age"));
//设置请求体
request.source(sourceBuilder);
//3.客户端发送请求,获取响应对象
SearchResponse response = client.search(request, RequestOptions.DEFAULT);
//4.打印响应结果
SearchHits hits = response.getHits();
System.out.println(response);
client.close();
}
}
1