【Elasticsearch7】3-基本操作

目录

RESTful

数据格式

HTTP操作

索引操作

倒排索引

创建索引

查看所有索引

查看单个索引

删除索引

文档操作

创建文档

查看文档

​编辑

全量修改

​编辑局部修改

删除文档

条件删除文档

高级查询

条件查询

URL带参查询

请求体带参查询

带请求体方式的查找所有内容

查询指定字段

分页查询

查询排序

多条件查询

范围查询

全文检索

完全匹配

高亮查询

聚合查询

映射操作

创建映射

查询映射

---

RESTful

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。

数据格式

ElasticSearch是面向文档型数据库，一条数据就是一个文档，将ElasticSearch里存储文档数据和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

ES6.X中，一个index下只能包含一个type，ES7.X中，Type的概念已被删除 

6用JSON作为文档序列化的格式，比如一条用户信息：

HTTP操作

索引操作

倒排索引

正排索引（传统）

倒排索引

创建索引

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

请求后，服务器返回响应：

 如果重复发 PUT 请求 ： http://127.0.0.1:9200/shopping 添加索引，会返回错误信息 :

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 :

 

查看单个索引

 在 Postman 中，向 ES 服务器发 GET 请求 ： http://127.0.0.1:9200/shopping

查看索引向ES服务器发送的请求路径和创建索引是一致的，但是HTTP方法不一致，这里可以体会一下RESTful的意义，请求后，服务器响应结果如下：

删除索引

在 Postman 中，向 ES 服务器发 DELETE 请求 ： http://127.0.0.1:9200/shopping

返回结果如下：

重新访问索引时，服务器返回响应：索引不存在 

文档操作

创建文档

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：

 注意，此处发送请求的方式必须为 POST，不能是 PUT，否则会发生错误。

服务器响应结果如下：

上面的数据创建后，由于没有指定数据唯一性标识（ID），默认情况下， ES 服务器会随机生成一个。

如果想要自定义唯一性标识，需要在创建时指定： http://127.0.0.1:9200/shopping/_doc/1，请求体JSON内容为：

 此处需要注意：如果增加数据时明确数据主键，那么请求方式也可以为 PUT。

查看文档

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/1 。

返回结果如下：

查找不存在的内容，向 ES 服务器发 GET 请求 ： http://127.0.0.1:9200/shopping/_doc/1001。

返回结果如下：

{"_index": "shopping","_type": "_doc","_id": "1001","found": false
}

查看索引下所有数据，向 ES 服务器发 GET 请求 ： http://127.0.0.1:9200/shopping/_search。

返回结果如下：

{"took": 133,"timed_out": false,"_shards": {"total": 1,"successful": 1,"skipped": 0,"failed": 0},"hits": {"total": {"value": 2,"relation": "eq"},"max_score": 1,"hits": [{"_index": "shopping","_type": "_doc","_id": "ANQqsHgBaKNfVnMbhZYU","_score": 1,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 3999}},{"_index": "shopping","_type": "_doc","_id": "1","_score": 1,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 3999}}]}
}

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 POST 请求 ： http://127.0.0.1:9200/shopping/_doc/1

请求体JSON内容为:

 修改成功后，服务器响应结果：

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/1。

请求体JSON内容为:

 返回结果如下：

根据唯一性标识，查询文档数据，文档数据已经更新

删除文档

删除一个文档不会立即从磁盘上移除，它只是被标记成已删除（逻辑删除）。

在 Postman 中，向 ES 服务器发 DELETE 请求 ： http://127.0.0.1:9200/shopping/_doc/1

返回结果：

删除后再查询当前文档信息

如果删除一个并不存在的文档

条件删除文档

一般删除数据都是根据文档的唯一性标识进行删除，实际操作时，也可以根据条件对多条数据进行删除

首先分别添加多条数据：

 向ES服务器发POST请求：http://127.0.0.1:9200/shopping/_delete_by_query

请求体内容为：

删除成功后，服务器响应结果：

高级查询

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：

{"took": 5,"timed_out": false,"_shards": {"total": 1,"successful": 1,"skipped": 0,"failed": 0},"hits": {"total": {"value": 6,"relation": "eq"},"max_score": 1,"hits": [{"_index": "shopping","_type": "_doc","_id": "ANQqsHgBaKNfVnMbhZYU","_score": 1,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 3999}},{"_index": "shopping","_type": "_doc","_id": "A9R5sHgBaKNfVnMb25Ya","_score": 1,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}},{"_index": "shopping","_type": "_doc","_id": "BNR5sHgBaKNfVnMb7pal","_score": 1,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}},{"_index": "shopping","_type": "_doc","_id": "BtR6sHgBaKNfVnMbX5Y5","_score": 1,"_source": {"title": "华为手机","category": "华为","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}},{"_index": "shopping","_type": "_doc","_id": "B9R6sHgBaKNfVnMbZpZ6","_score": 1,"_source": {"title": "华为手机","category": "华为","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}},{"_index": "shopping","_type": "_doc","_id": "CdR7sHgBaKNfVnMbsJb9","_score": 1,"_source": {"title": "华为手机","category": "华为","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}}]}
}

URL带参查询

查找category为小米的文档，在 Postman 中，向 ES 服务器发 GET请求 ： http://127.0.0.1:9200/shopping/_search?q=category:小米，返回结果如下：

{"took": 94,"timed_out": false,"_shards": {"total": 1,"successful": 1,"skipped": 0,"failed": 0},"hits": {"total": {"value": 3,"relation": "eq"},"max_score": 1.3862942,"hits": [{"_index": "shopping","_type": "_doc","_id": "ANQqsHgBaKNfVnMbhZYU","_score": 1.3862942,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 3999}},{"_index": "shopping","_type": "_doc","_id": "A9R5sHgBaKNfVnMb25Ya","_score": 1.3862942,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}},{"_index": "shopping","_type": "_doc","_id": "BNR5sHgBaKNfVnMb7pal","_score": 1.3862942,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}}]}
}

上述为URL带参数形式查询，这很容易让不善者心怀恶意，或者参数值出现中文会出现乱码情况。为了避免这些情况，我们可用使用带JSON请求体请求进行查询。

请求体带参查询

接下带JSON请求体，还是查找category为小米的文档，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：

{"query":{"match":{"category":"小米"}}
}

返回结果如下：

{"took": 3,"timed_out": false,"_shards": {"total": 1,"successful": 1,"skipped": 0,"failed": 0},"hits": {"total": {"value": 3,"relation": "eq"},"max_score": 1.3862942,"hits": [{"_index": "shopping","_type": "_doc","_id": "ANQqsHgBaKNfVnMbhZYU","_score": 1.3862942,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 3999}},{"_index": "shopping","_type": "_doc","_id": "A9R5sHgBaKNfVnMb25Ya","_score": 1.3862942,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}},{"_index": "shopping","_type": "_doc","_id": "BNR5sHgBaKNfVnMb7pal","_score": 1.3862942,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}}]}
}

带请求体方式的查找所有内容

查找所有文档内容，也可以这样，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：

{"query":{"match_all":{}}
}

则返回所有文档内容：

{"took": 2,"timed_out": false,"_shards": {"total": 1,"successful": 1,"skipped": 0,"failed": 0},"hits": {"total": {"value": 6,"relation": "eq"},"max_score": 1,"hits": [{"_index": "shopping","_type": "_doc","_id": "ANQqsHgBaKNfVnMbhZYU","_score": 1,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 3999}},{"_index": "shopping","_type": "_doc","_id": "A9R5sHgBaKNfVnMb25Ya","_score": 1,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}},{"_index": "shopping","_type": "_doc","_id": "BNR5sHgBaKNfVnMb7pal","_score": 1,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}},{"_index": "shopping","_type": "_doc","_id": "BtR6sHgBaKNfVnMbX5Y5","_score": 1,"_source": {"title": "华为手机","category": "华为","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}},{"_index": "shopping","_type": "_doc","_id": "B9R6sHgBaKNfVnMbZpZ6","_score": 1,"_source": {"title": "华为手机","category": "华为","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}},{"_index": "shopping","_type": "_doc","_id": "CdR7sHgBaKNfVnMbsJb9","_score": 1,"_source": {"title": "华为手机","category": "华为","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}}]}
}

查询指定字段

如果想查询指定字段，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：

{"query":{"match_all":{}},"_source":["title"]
}

返回结果如下：

{"took": 5,"timed_out": false,"_shards": {"total": 1,"successful": 1,"skipped": 0,"failed": 0},"hits": {"total": {"value": 6,"relation": "eq"},"max_score": 1,"hits": [{"_index": "shopping","_type": "_doc","_id": "ANQqsHgBaKNfVnMbhZYU","_score": 1,"_source": {"title": "小米手机"}},{"_index": "shopping","_type": "_doc","_id": "A9R5sHgBaKNfVnMb25Ya","_score": 1,"_source": {"title": "小米手机"}},{"_index": "shopping","_type": "_doc","_id": "BNR5sHgBaKNfVnMb7pal","_score": 1,"_source": {"title": "小米手机"}},{"_index": "shopping","_type": "_doc","_id": "BtR6sHgBaKNfVnMbX5Y5","_score": 1,"_source": {"title": "华为手机"}},{"_index": "shopping","_type": "_doc","_id": "B9R6sHgBaKNfVnMbZpZ6","_score": 1,"_source": {"title": "华为手机"}},{"_index": "shopping","_type": "_doc","_id": "CdR7sHgBaKNfVnMbsJb9","_score": 1,"_source": {"title": "华为手机"}}]}
}

分页查询

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：

{"query":{"match_all":{}},"from":0,"size":2
}

返回结果如下：

{"took": 1,"timed_out": false,"_shards": {"total": 1,"successful": 1,"skipped": 0,"failed": 0},"hits": {"total": {"value": 6,"relation": "eq"},"max_score": 1,"hits": [{"_index": "shopping","_type": "_doc","_id": "ANQqsHgBaKNfVnMbhZYU","_score": 1,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 3999}},{"_index": "shopping","_type": "_doc","_id": "A9R5sHgBaKNfVnMb25Ya","_score": 1,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}}]}
}

查询排序

如果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，附带JSON体如下：

{"query":{"match_all":{}},"sort":{"price":{"order":"desc"}}
}

返回结果如下：

{"took": 96,"timed_out": false,"_shards": {"total": 1,"successful": 1,"skipped": 0,"failed": 0},"hits": {"total": {"value": 6,"relation": "eq"},"max_score": null,"hits": [{"_index": "shopping","_type": "_doc","_id": "ANQqsHgBaKNfVnMbhZYU","_score": null,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 3999},"sort": [3999]},{"_index": "shopping","_type": "_doc","_id": "A9R5sHgBaKNfVnMb25Ya","_score": null,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999},"sort": [1999]},{"_index": "shopping","_type": "_doc","_id": "BNR5sHgBaKNfVnMb7pal","_score": null,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999},"sort": [1999]},{"_index": "shopping","_type": "_doc","_id": "BtR6sHgBaKNfVnMbX5Y5","_score": null,"_source": {"title": "华为手机","category": "华为","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999},"sort": [1999]},{"_index": "shopping","_type": "_doc","_id": "B9R6sHgBaKNfVnMbZpZ6","_score": null,"_source": {"title": "华为手机","category": "华为","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999},"sort": [1999]},{"_index": "shopping","_type": "_doc","_id": "CdR7sHgBaKNfVnMbsJb9","_score": null,"_source": {"title": "华为手机","category": "华为","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999},"sort": [1999]}]}
}

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：

{"query":{"bool":{"must":[{"match":{"category":"小米"}},{"match":{"price":3999.00}}]}}
}

返回结果如下：

{"took": 134,"timed_out": false,"_shards": {"total": 1,"successful": 1,"skipped": 0,"failed": 0},"hits": {"total": {"value": 1,"relation": "eq"},"max_score": 2.3862944,"hits": [{"_index": "shopping","_type": "_doc","_id": "ANQqsHgBaKNfVnMbhZYU","_score": 2.3862944,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 3999}}]}
}

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：

{"query":{"bool":{"should":[{"match":{"category":"小米"}},{"match":{"category":"华为"}}]},"filter":{"range":{"price":{"gt":2000}}}}
}

返回结果如下：

{"took": 8,"timed_out": false,"_shards": {"total": 1,"successful": 1,"skipped": 0,"failed": 0},"hits": {"total": {"value": 6,"relation": "eq"},"max_score": 1.3862942,"hits": [{"_index": "shopping","_type": "_doc","_id": "ANQqsHgBaKNfVnMbhZYU","_score": 1.3862942,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 3999}},{"_index": "shopping","_type": "_doc","_id": "A9R5sHgBaKNfVnMb25Ya","_score": 1.3862942,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}},{"_index": "shopping","_type": "_doc","_id": "BNR5sHgBaKNfVnMb7pal","_score": 1.3862942,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}},{"_index": "shopping","_type": "_doc","_id": "BtR6sHgBaKNfVnMbX5Y5","_score": 1.3862942,"_source": {"title": "华为手机","category": "华为","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}},{"_index": "shopping","_type": "_doc","_id": "B9R6sHgBaKNfVnMbZpZ6","_score": 1.3862942,"_source": {"title": "华为手机","category": "华为","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}},{"_index": "shopping","_type": "_doc","_id": "CdR7sHgBaKNfVnMbsJb9","_score": 1.3862942,"_source": {"title": "华为手机","category": "华为","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}}]}
}

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：

{"query":{"bool":{"should":[{"match":{"category":"小米"}},{"match":{"category":"华为"}}],"filter":{"range":{"price":{"gt":2000}}}}}
}

返回结果如下：

{"took": 72,"timed_out": false,"_shards": {"total": 1,"successful": 1,"skipped": 0,"failed": 0},"hits": {"total": {"value": 1,"relation": "eq"},"max_score": 1.3862942,"hits": [{"_index": "shopping","_type": "_doc","_id": "ANQqsHgBaKNfVnMbhZYU","_score": 1.3862942,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 3999}}]}
}

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：

{"query":{"match":{"category" : "小华"}}
}

返回结果如下：

{"took": 7,"timed_out": false,"_shards": {"total": 1,"successful": 1,"skipped": 0,"failed": 0},"hits": {"total": {"value": 6,"relation": "eq"},"max_score": 0.6931471,"hits": [{"_index": "shopping","_type": "_doc","_id": "ANQqsHgBaKNfVnMbhZYU","_score": 0.6931471,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 3999}},{"_index": "shopping","_type": "_doc","_id": "A9R5sHgBaKNfVnMb25Ya","_score": 0.6931471,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}},{"_index": "shopping","_type": "_doc","_id": "BNR5sHgBaKNfVnMb7pal","_score": 0.6931471,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}},{"_index": "shopping","_type": "_doc","_id": "BtR6sHgBaKNfVnMbX5Y5","_score": 0.6931471,"_source": {"title": "华为手机","category": "华为","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}},{"_index": "shopping","_type": "_doc","_id": "B9R6sHgBaKNfVnMbZpZ6","_score": 0.6931471,"_source": {"title": "华为手机","category": "华为","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}},{"_index": "shopping","_type": "_doc","_id": "CdR7sHgBaKNfVnMbsJb9","_score": 0.6931471,"_source": {"title": "华为手机","category": "华为","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}}]}
}

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：

{"query":{"match_phrase":{"category" : "为"}}
}

返回结果如下：

{"took": 2,"timed_out": false,"_shards": {"total": 1,"successful": 1,"skipped": 0,"failed": 0},"hits": {"total": {"value": 3,"relation": "eq"},"max_score": 0.6931471,"hits": [{"_index": "shopping","_type": "_doc","_id": "BtR6sHgBaKNfVnMbX5Y5","_score": 0.6931471,"_source": {"title": "华为手机","category": "华为","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}},{"_index": "shopping","_type": "_doc","_id": "B9R6sHgBaKNfVnMbZpZ6","_score": 0.6931471,"_source": {"title": "华为手机","category": "华为","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}},{"_index": "shopping","_type": "_doc","_id": "CdR7sHgBaKNfVnMbsJb9","_score": 0.6931471,"_source": {"title": "华为手机","category": "华为","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}}]}
}

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：

{"query":{"match_phrase":{"category" : "为"}},"highlight":{"fields":{"category":{}//<----高亮这字段}}
}

返回结果如下：

{"took": 100,"timed_out": false,"_shards": {"total": 1,"successful": 1,"skipped": 0,"failed": 0},"hits": {"total": {"value": 3,"relation": "eq"},"max_score": 0.6931471,"hits": [{"_index": "shopping","_type": "_doc","_id": "BtR6sHgBaKNfVnMbX5Y5","_score": 0.6931471,"_source": {"title": "华为手机","category": "华为","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999},"highlight": {"category": ["华<em>为</em>"//<------高亮一个为字。]}},{"_index": "shopping","_type": "_doc","_id": "B9R6sHgBaKNfVnMbZpZ6","_score": 0.6931471,"_source": {"title": "华为手机","category": "华为","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999},"highlight": {"category": ["华<em>为</em>"]}},{"_index": "shopping","_type": "_doc","_id": "CdR7sHgBaKNfVnMbsJb9","_score": 0.6931471,"_source": {"title": "华为手机","category": "华为","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999},"highlight": {"category": ["华<em>为</em>"]}}]}
}

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：

{"aggs":{//聚合操作"price_group":{//名称，随意起名"terms":{//分组"field":"price"//分组字段}}}
}

 返回结果如下：

{"took": 63,"timed_out": false,"_shards": {"total": 1,"successful": 1,"skipped": 0,"failed": 0},"hits": {"total": {"value": 6,"relation": "eq"},"max_score": 1,"hits": [{"_index": "shopping","_type": "_doc","_id": "ANQqsHgBaKNfVnMbhZYU","_score": 1,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 3999}},{"_index": "shopping","_type": "_doc","_id": "A9R5sHgBaKNfVnMb25Ya","_score": 1,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}},{"_index": "shopping","_type": "_doc","_id": "BNR5sHgBaKNfVnMb7pal","_score": 1,"_source": {"title": "小米手机","category": "小米","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}},{"_index": "shopping","_type": "_doc","_id": "BtR6sHgBaKNfVnMbX5Y5","_score": 1,"_source": {"title": "华为手机","category": "华为","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}},{"_index": "shopping","_type": "_doc","_id": "B9R6sHgBaKNfVnMbZpZ6","_score": 1,"_source": {"title": "华为手机","category": "华为","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}},{"_index": "shopping","_type": "_doc","_id": "CdR7sHgBaKNfVnMbsJb9","_score": 1,"_source": {"title": "华为手机","category": "华为","images": "http://www.gulixueyuan.com/xm.jpg","price": 1999}}]},"aggregations": {"price_group": {"doc_count_error_upper_bound": 0,"sum_other_doc_count": 0,"buckets": [{"key": 1999,"doc_count": 5},{"key": 3999,"doc_count": 1}]}}
}

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，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：

{"aggs":{"price_group":{"terms":{"field":"price"}}},"size":0
}

返回结果如下：

{"took": 60,"timed_out": false,"_shards": {"total": 1,"successful": 1,"skipped": 0,"failed": 0},"hits": {"total": {"value": 6,"relation": "eq"},"max_score": null,"hits": []},"aggregations": {"price_group": {"doc_count_error_upper_bound": 0,"sum_other_doc_count": 0,"buckets": [{"key": 1999,"doc_count": 5},{"key": 3999,"doc_count": 1}]}}
}

若想对所有手机价格求平均值。

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：

{"aggs":{"price_avg":{//名称，随意起名"avg":{//求平均"field":"price"}}},"size":0
}

 返回结果如下：

{"took": 14,"timed_out": false,"_shards": {"total": 1,"successful": 1,"skipped": 0,"failed": 0},"hits": {"total": {"value": 6,"relation": "eq"},"max_score": null,"hits": []},"aggregations": {"price_avg": {"value": 2332.3333333333335}}
}

映射操作

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)。

创建映射

先创建一个索引：

# PUT http://127.0.0.1:9200/user

返回结果：

{"acknowledged": true,"shards_acknowledged": true,"index": "user"
}

创建映射：

# PUT http://127.0.0.1:9200/user/_mapping{"properties": {"name":{"type": "text","index": true},"sex":{"type": "keyword","index": true},"tel":{"type": "keyword","index": false}}
}

 返回结果如下：

{"acknowledged": true
}

查询映射

#GET http://127.0.0.1:9200/user/_mapping

返回结果如下：

{"user": {"mappings": {"properties": {"name": {"type": "text"},"sex": {"type": "keyword"},"tel": {"type": "keyword","index": false}}}}
}

增加数据：

#PUT http://127.0.0.1:9200/user/_create/1001
{"name":"小米","sex":"男的","tel":"1111"
}

返回结果如下：

{"_index": "user","_type": "_doc","_id": "1001","_version": 1,"result": "created","_shards": {"total": 2,"successful": 1,"failed": 0},"_seq_no": 0,"_primary_term": 1
}

查找name含有”小“数据：

#GET http://127.0.0.1:9200/user/_search
{"query":{"match":{"name":"小"}}
}

返回结果如下：

{"took": 495,"timed_out": false,"_shards": {"total": 1,"successful": 1,"skipped": 0,"failed": 0},"hits": {"total": {"value": 1,"relation": "eq"},"max_score": 0.2876821,"hits": [{"_index": "user","_type": "_doc","_id": "1001","_score": 0.2876821,"_source": {"name": "小米","sex": "男的","tel": "1111"}}]}
}

查找sex含有”男“数据：

#GET http://127.0.0.1:9200/user/_search
{"query":{"match":{"sex":"男"}}
}

返回结果如下：

{"took": 1,"timed_out": false,"_shards": {"total": 1,"successful": 1,"skipped": 0,"failed": 0},"hits": {"total": {"value": 0,"relation": "eq"},"max_score": null,"hits": []}
}

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。

#GET http://127.0.0.1:9200/user/_search
{"query":{"match":{"sex":"男的"}}
}

返回结果如下：

{"took": 2,"timed_out": false,"_shards": {"total": 1,"successful": 1,"skipped": 0,"failed": 0},"hits": {"total": {"value": 1,"relation": "eq"},"max_score": 0.2876821,"hits": [{"_index": "user","_type": "_doc","_id": "1001","_score": 0.2876821,"_source": {"name": "小米","sex": "男的","tel": "1111"}}]}
}

查询电话

# GET http://127.0.0.1:9200/user/_search
{"query":{"match":{"tel":"11"}}
}

返回结果如下：

{"error": {"root_cause": [{"type": "query_shard_exception","reason": "failed to create query: Cannot search on field [tel] since it is not indexed.","index_uuid": "ivLnMfQKROS7Skb2MTFOew","index": "user"}],"type": "search_phase_execution_exception","reason": "all shards failed","phase": "query","grouped": true,"failed_shards": [{"shard": 0,"index": "user","node": "4P7dIRfXSbezE5JTiuylew","reason": {"type": "query_shard_exception","reason": "failed to create query: Cannot search on field [tel] since it is not indexed.","index_uuid": "ivLnMfQKROS7Skb2MTFOew","index": "user","caused_by": {"type": "illegal_argument_exception","reason": "Cannot search on field [tel] since it is not indexed."}}}]},"status": 400
}

报错只因创建映射时"tel"的"index"为false。