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文章目录
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本篇主要讲述 Elasticsearch 关于搜索结果的处理，主要内容有：分页查询、结果排序、指定返回字段、去重、高亮显示等。
Elasticsearch 对所有查询都进行了分页，默认返回前 10 条数据。如果想要查询更多的数据，就需要使用分页参数了。Elasticsearch 提供了两个参数 from 和 size 来控制分页结果。
from 表示从第几条数据开始查询，默认值为 0
size 表示返回数据量大小，默认值为 10
注：分页也有一定的限制，不能查询
from+size超过 10000 的数据。
GET /mt_product/_search
{
"query": {
"match_all": {}
},
"from": 0,
"size": 5
}
查询结果：
{
"took" : 1,
"timed_out" : false,
"_shards" : {
"total" : 1,
"successful" : 1,
"skipped" : 0,
"failed" : 0
},
"hits" : {
"total" : {
"value" : 12,
"relation" : "eq"
},
"max_score" : 1.0,
"hits" : [
{
"_index" : "mt_product",
"_type" : "_doc",
"_id" : "1",
"_score" : 1.0,
"_source" : {
"id" : 1,
"name" : "招牌海苔单人餐",
"tags" : [
"寿司"
],
"price" : 9.9,
"sales" : 1000,
"score" : 4.7,
"store_id" : 1,
"store_name" : "M多寿司",
"create_time" : "2023-01-18 08:01:00"
}
},
{
"_index" : "mt_product",
"_type" : "_doc",
"_id" : "2",
"_score" : 1.0,
"_source" : {
"id" : 2,
"name" : "1-2人招牌双拼套餐",
"tags" : [
"寿司"
],
"price" : 18.9,
"sales" : 1200,
"score" : 4.8,
"store_id" : 1,
"store_name" : "M多寿司",
"create_time" : "2023-01-18 08:02:00"
}
},
{
"_index" : "mt_product",
"_type" : "_doc",
"_id" : "3",
"_score" : 1.0,
"_source" : {
"id" : 3,
"name" : "三文鱼寿司",
"tags" : [
"寿司,鱼肉"
],
"price" : 16.9,
"sales" : 820,
"score" : 4.9,
"store_id" : 2,
"store_name" : "爱食寿司",
"create_time" : "2023-01-18 08:03:00"
}
},
{
"_index" : "mt_product",
"_type" : "_doc",
"_id" : "4",
"_score" : 1.0,
"_source" : {
"id" : 4,
"name" : "极上全品寿司套餐",
"tags" : [
"寿司"
],
"price" : 25,
"sales" : 1500,
"score" : 4.6,
"store_id" : 2,
"store_name" : "爱食寿司",
"create_time" : "2023-01-18 08:04:00"
}
},
{
"_index" : "mt_product",
"_type" : "_doc",
"_id" : "5",
"_score" : 1.0,
"_source" : {
"id" : 5,
"name" : "劲脆鸡腿汉堡",
"tags" : [
"汉堡,鸡肉"
],
"price" : 21.5,
"sales" : 200,
"score" : 4.5,
"store_id" : 3,
"store_name" : "肯德基",
"create_time" : "2023-01-18 08:05:00"
}
}
]
}
}
GET /mt_product/_search
{
"query": {
"match_all": {}
},
"from": 5,
"size": 5
}
查询结果：
{
"took" : 0,
"timed_out" : false,
"_shards" : {
"total" : 1,
"successful" : 1,
"skipped" : 0,
"failed" : 0
},
"hits" : {
"total" : {
"value" : 12,
"relation" : "eq"
},
"max_score" : 1.0,
"hits" : [
{
"_index" : "mt_product",
"_type" : "_doc",
"_id" : "6",
"_score" : 1.0,
"_source" : {
"id" : 6,
"name" : "香辣鸡腿汉堡",
"tags" : [
"汉堡,鸡肉"
],
"price" : 21.5,
"sales" : 98,
"score" : 4.4,
"store_id" : 3,
"store_name" : "肯德基",
"create_time" : "2023-01-18 08:06:00"
}
},
{
"_index" : "mt_product",
"_type" : "_doc",
"_id" : "7",
"_score" : 1.0,
"_source" : {
"id" : 7,
"name" : "20块香辣鸡翅",
"tags" : [
"鸡肉"
],
"price" : 99,
"sales" : 5,
"score" : 4.8,
"store_id" : 3,
"store_name" : "肯德基",
"create_time" : "2023-01-18 08:07:00"
}
},
{
"_index" : "mt_product",
"_type" : "_doc",
"_id" : "8",
"_score" : 1.0,
"_source" : {
"id" : 8,
"name" : "3层芝士年堡套餐",
"tags" : [
"汉堡"
],
"price" : 29,
"sales" : 4000,
"score" : 4.9,
"store_id" : 4,
"store_name" : "汉堡王",
"create_time" : "2023-01-18 08:08:00"
}
},
{
"_index" : "mt_product",
"_type" : "_doc",
"_id" : "9",
"_score" : 1.0,
"_source" : {
"id" : 9,
"name" : "霸道小酥鸡+薯霸王",
"tags" : [
"汉堡,鸡肉"
],
"price" : 19,
"sales" : 300,
"score" : 4.2,
"store_id" : 4,
"store_name" : "汉堡王",
"create_time" : "2023-01-18 08:09:00"
}
},
{
"_index" : "mt_product",
"_type" : "_doc",
"_id" : "10",
"_score" : 1.0,
"_source" : {
"id" : 10,
"name" : "双层原味板烧鸡腿麦满分四件套",
"tags" : [
"汉堡,鸡肉"
],
"price" : 29,
"sales" : 3000,
"score" : 4.8,
"store_id" : 5,
"store_name" : "麦当劳",
"create_time" : "2023-01-18 08:10:00"
}
}
]
}
}
GET /mt_product/_search
{
"query": {
"match_all": {}
},
"from": 10,
"size": 5
}
查询结果：
{
"took" : 0,
"timed_out" : false,
"_shards" : {
"total" : 1,
"successful" : 1,
"skipped" : 0,
"failed" : 0
},
"hits" : {
"total" : {
"value" : 12,
"relation" : "eq"
},
"max_score" : 1.0,
"hits" : [
{
"_index" : "mt_product",
"_type" : "_doc",
"_id" : "11",
"_score" : 1.0,
"_source" : {
"id" : 11,
"name" : "火腿扒麦满分组合",
"tags" : [
"汉堡"
],
"price" : 8,
"sales" : 100000,
"score" : 4.9,
"store_id" : 5,
"store_name" : "麦当劳",
"create_time" : "2023-01-18 08:11:00"
}
},
{
"_index" : "mt_product",
"_type" : "_doc",
"_id" : "12",
"_score" : 1.0,
"_source" : {
"id" : 12,
"name" : "原味板烧鸡腿麦满组件",
"tags" : [
"汉堡,鸡肉"
],
"price" : 9.9,
"sales" : 140000,
"score" : 4.9,
"store_id" : 5,
"store_name" : "麦当劳",
"create_time" : "2023-01-18 08:12:00"
}
}
]
}
}
Elasticsearch 支持按指定的字段进行排序，使用 sort 参数来设置排序，排序字段也可以是多个。排序选项中正序使用 asc，倒序使用 desc。
GET /mt_product/_search
{
"query": {
"match_all": {}
},
"size": 3,
"sort": [
{
"id": {
"order": "asc"
}
}
]
}
查询结果：
{
"took" : 0,
"timed_out" : false,
"_shards" : {
"total" : 1,
"successful" : 1,
"skipped" : 0,
"failed" : 0
},
"hits" : {
"total" : {
"value" : 12,
"relation" : "eq"
},
"max_score" : null,
"hits" : [
{
"_index" : "mt_product",
"_type" : "_doc",
"_id" : "1",
"_score" : null,
"_source" : {
"id" : 1,
"name" : "招牌海苔单人餐",
"tags" : [
"寿司"
],
"price" : 9.9,
"sales" : 1000,
"score" : 4.7,
"store_id" : 1,
"store_name" : "M多寿司",
"create_time" : "2023-01-18 08:01:00"
},
"sort" : [
1
]
},
{
"_index" : "mt_product",
"_type" : "_doc",
"_id" : "2",
"_score" : null,
"_source" : {
"id" : 2,
"name" : "1-2人招牌双拼套餐",
"tags" : [
"寿司"
],
"price" : 18.9,
"sales" : 1200,
"score" : 4.8,
"store_id" : 1,
"store_name" : "M多寿司",
"create_time" : "2023-01-18 08:02:00"
},
"sort" : [
2
]
},
{
"_index" : "mt_product",
"_type" : "_doc",
"_id" : "3",
"_score" : null,
"_source" : {
"id" : 3,
"name" : "三文鱼寿司",
"tags" : [
"寿司,鱼肉"
],
"price" : 16.9,
"sales" : 820,
"score" : 4.9,
"store_id" : 2,
"store_name" : "爱食寿司",
"create_time" : "2023-01-18 08:03:00"
},
"sort" : [
3
]
}
]
}
}
GET /mt_product/_search
{
"query": {
"match_all": {}
},
"size": 3,
"sort": [
{
"id": {
"order": "desc"
}
}
]
}
查询结果：
{
"took" : 0,
"timed_out" : false,
"_shards" : {
"total" : 1,
"successful" : 1,
"skipped" : 0,
"failed" : 0
},
"hits" : {
"total" : {
"value" : 12,
"relation" : "eq"
},
"max_score" : null,
"hits" : [
{
"_index" : "mt_product",
"_type" : "_doc",
"_id" : "12",
"_score" : null,
"_source" : {
"id" : 12,
"name" : "原味板烧鸡腿麦满组件",
"tags" : [
"汉堡,鸡肉"
],
"price" : 9.9,
"sales" : 140000,
"score" : 4.9,
"store_id" : 5,
"store_name" : "麦当劳",
"create_time" : "2023-01-18 08:12:00"
},
"sort" : [
12
]
},
{
"_index" : "mt_product",
"_type" : "_doc",
"_id" : "11",
"_score" : null,
"_source" : {
"id" : 11,
"name" : "火腿扒麦满分组合",
"tags" : [
"汉堡"
],
"price" : 8,
"sales" : 100000,
"score" : 4.9,
"store_id" : 5,
"store_name" : "麦当劳",
"create_time" : "2023-01-18 08:11:00"
},
"sort" : [
11
]
},
{
"_index" : "mt_product",
"_type" : "_doc",
"_id" : "10",
"_score" : null,
"_source" : {
"id" : 10,
"name" : "双层原味板烧鸡腿麦满分四件套",
"tags" : [
"汉堡,鸡肉"
],
"price" : 29,
"sales" : 3000,
"score" : 4.8,
"store_id" : 5,
"store_name" : "麦当劳",
"create_time" : "2023-01-18 08:10:00"
},
"sort" : [
10
]
}
]
}
}
在实际的查询中，我们通过是有选择地返回我们想要的字段，这样会节省带宽和内存的使用。Elasticsearch 通过两个参数来指定返回字段：
fields：用来指定返回的字段
_source：将 _source 设为 false，表示不会返回所有完整文档数据（文档数据存在 _source 中）。
GET /mt_product/_search
{
"query": {
"match_all": {}
},
"size": 3,
"fields": [
"id",
"name"
],
"_source": false
}
查询结果：
{
"took" : 0,
"timed_out" : false,
"_shards" : {
"total" : 1,
"successful" : 1,
"skipped" : 0,
"failed" : 0
},
"hits" : {
"total" : {
"value" : 12,
"relation" : "eq"
},
"max_score" : 1.0,
"hits" : [
{
"_index" : "mt_product",
"_type" : "_doc",
"_id" : "1",
"_score" : 1.0,
"fields" : {
"name" : [
"招牌海苔单人餐"
],
"id" : [
1
]
}
},
{
"_index" : "mt_product",
"_type" : "_doc",
"_id" : "2",
"_score" : 1.0,
"fields" : {
"name" : [
"1-2人招牌双拼套餐"
],
"id" : [
2
]
}
},
{
"_index" : "mt_product",
"_type" : "_doc",
"_id" : "3",
"_score" : 1.0,
"fields" : {
"name" : [
"三文鱼寿司"
],
"id" : [
3
]
}
}
]
}
}
当我们的索引中存在重复数据时，可以将其去重。Elasticsearch 通过 collapse 参数来实现去重，去重时需要指定字段。
GET /mt_product/_search
{
"query": {
"match_all": {}
},
"collapse": {
"field": "store_id"
}
}
响应结果：
{
"took" : 0,
"timed_out" : false,
"_shards" : {
"total" : 1,
"successful" : 1,
"skipped" : 0,
"failed" : 0
},
"hits" : {
"total" : {
"value" : 12,
"relation" : "eq"
},
"max_score" : null,
"hits" : [
{
"_index" : "mt_product",
"_type" : "_doc",
"_id" : "1",
"_score" : 1.0,
"_source" : {
"id" : 1,
"name" : "招牌海苔单人餐",
"tags" : [
"寿司"
],
"price" : 9.9,
"sales" : 1000,
"score" : 4.7,
"store_id" : 1,
"store_name" : "M多寿司",
"create_time" : "2023-01-18 08:01:00"
},
"fields" : {
"store_id" : [
"1"
]
}
},
{
"_index" : "mt_product",
"_type" : "_doc",
"_id" : "3",
"_score" : 1.0,
"_source" : {
"id" : 3,
"name" : "三文鱼寿司",
"tags" : [
"寿司,鱼肉"
],
"price" : 16.9,
"sales" : 820,
"score" : 4.9,
"store_id" : 2,
"store_name" : "爱食寿司",
"create_time" : "2023-01-18 08:03:00"
},
"fields" : {
"store_id" : [
"2"
]
}
},
{
"_index" : "mt_product",
"_type" : "_doc",
"_id" : "5",
"_score" : 1.0,
"_source" : {
"id" : 5,
"name" : "劲脆鸡腿汉堡",
"tags" : [
"汉堡,鸡肉"
],
"price" : 21.5,
"sales" : 200,
"score" : 4.5,
"store_id" : 3,
"store_name" : "肯德基",
"create_time" : "2023-01-18 08:05:00"
},
"fields" : {
"store_id" : [
"3"
]
}
},
{
"_index" : "mt_product",
"_type" : "_doc",
"_id" : "8",
"_score" : 1.0,
"_source" : {
"id" : 8,
"name" : "3层芝士年堡套餐",
"tags" : [
"汉堡"
],
"price" : 29,
"sales" : 4000,
"score" : 4.9,
"store_id" : 4,
"store_name" : "汉堡王",
"create_time" : "2023-01-18 08:08:00"
},
"fields" : {
"store_id" : [
"4"
]
}
},
{
"_index" : "mt_product",
"_type" : "_doc",
"_id" : "10",
"_score" : 1.0,
"_source" : {
"id" : 10,
"name" : "双层原味板烧鸡腿麦满分四件套",
"tags" : [
"汉堡,鸡肉"
],
"price" : 29,
"sales" : 3000,
"score" : 4.8,
"store_id" : 5,
"store_name" : "麦当劳",
"create_time" : "2023-01-18 08:10:00"
},
"fields" : {
"store_id" : [
"5"
]
}
}
]
}
}
Elasticsearch 可以将搜索关键字做高亮显示，可以指定高亮显示的字段，会在响应结果中对关键字加 <em> 标签，便于前端特殊处理。
GET /mt_product/_search
{
"query": {
"multi_match": {
"query": "寿司",
"fields": ["name", "tag"]
}
},
"highlight": {
"fields": {
"name": {}
}
}
}
查询结果：
{
"took" : 1,
"timed_out" : false,
"_shards" : {
"total" : 1,
"successful" : 1,
"skipped" : 0,
"failed" : 0
},
"hits" : {
"total" : {
"value" : 2,
"relation" : "eq"
},
"max_score" : 1.7955686,
"hits" : [
{
"_index" : "mt_product",
"_type" : "_doc",
"_id" : "3",
"_score" : 1.7955686,
"_source" : {
"id" : 3,
"name" : "三文鱼寿司",
"tags" : [
"寿司,鱼肉"
],
"price" : 16.9,
"sales" : 820,
"score" : 4.9,
"store_id" : 2,
"store_name" : "爱食寿司",
"create_time" : "2023-01-18 08:03:00"
},
"highlight" : {
"name" : [
"三文鱼<em>寿司</em>"
]
}
},
{
"_index" : "mt_product",
"_type" : "_doc",
"_id" : "4",
"_score" : 1.6760855,
"_source" : {
"id" : 4,
"name" : "极上全品寿司套餐",
"tags" : [
"寿司"
],
"price" : 25,
"sales" : 1500,
"score" : 4.6,
"store_id" : 2,
"store_name" : "爱食寿司",
"create_time" : "2023-01-18 08:04:00"
},
"highlight" : {
"name" : [
"极上全品<em>寿司</em>套餐"
]
}
}
]
}
}
🔥 Elasticsearch 核心技术（一）：Elasticsearch 安装、配置、运行（Windows 版）
🔥 Elasticsearch 核心技术（二）：elasticsearch-head 插件安装和使用
🔥 Elasticsearch 核心技术（三）：Kibana 安装、配置、运行（Windows 版）
🔥 Elasticsearch 核心技术（四）：索引管理、映射管理、文档管理（REST API）
🔥 Elasticsearch 核心技术（五）：常用数据类型详解
🔥 Elasticsearch 核心技术（六）：内置的 8 种分词器详解 + 代码示例
🔥 Elasticsearch 核心技术（七）：IK 中文分词器的安装、使用、自定义字典
🔥 Elasticsearch 核心技术（八）：常用 DSL 查询（全文搜索、精确匹配、布尔查询）
👍 《Python入门核心技术》
👍 《IDEA 教程：从入门到精通》
👍 《Java 教程：从入门到精通》
👍 《MySQL 教程：从入门到精通》
👍 《大数据核心技术从入门到精通》
Rackup通过Rack的默认处理程序成功运行任何Rack应用程序。例如:classRackAppdefcall(environment)['200',{'Content-Type'=>'text/html'},["Helloworld"]]endendrunRackApp.new但是当最后一行更改为使用Rack的内置CGI处理程序时，rackup给出“NoMethodErrorat/undefinedmethod`call'fornil:NilClass”:Rack::Handler::CGI.runRackApp.newRack的其他内置处理程序也提出了同样的反对意见。例如Rack
我有一个表单，其中有很多字段取自数组(而不是模型或对象)。我如何验证这些字段的存在？solve_problem_pathdo|f|%>... 最佳答案 创建一个简单的类来包装请求参数并使用ActiveModel::Validations。#definedsomewhere,atthesimplest:require'ostruct'classSolvetrue#youcouldevencheckthesolutionwithavalidatorvalidatedoerrors.add(:base,"WRONG!!!")unlesss
我想向我的Controller传递一个参数，它是一个简单的复选框，但我不知道如何在模型的form_for中引入它，这是我的观点:{:id=>'go_finance'}do|f|%>Transferirde:para:Entrada:"input",:placeholder=>"Quantofoiganho?"%>Saída:"output",:placeholder=>"Quantofoigasto?"%>Nota:我想做一个额外的复选框，但我该怎么做，模型中没有一个对象，而是一个要检查的对象，以便在Controller中创建一个ifelse，如果没有检查，请帮助我，非常感谢,谢谢
我知道我可以指定某些字段来使用pluck查询数据库。ids=Item.where('due_at但是我想知道，是否有一种方法可以指定我想避免从数据库查询的某些字段。某种反拔？posts=Post.where(published:true).do_not_lookup(:enormous_field) 最佳答案 Model#attribute_names应该返回列/属性数组。您可以排除其中一些并传递给pluck或select方法。像这样:posts=Post.where(published:true).select(Post.attr
我使用Nokogiri(Rubygem)css搜索寻找某些在我的html里面。看起来Nokogiri的css搜索不喜欢正则表达式。我想切换到Nokogiri的xpath搜索，因为这似乎支持搜索字符串中的正则表达式。如何在xpath搜索中实现下面提到的(伪)css搜索？require'rubygems'require'nokogiri'value=Nokogiri::HTML.parse(ABBlaCD3"HTML_END#my_blockisgivenmy_bl="1"#my_eqcorrespondstothisregexmy_eq="\/[0-9]+\/"#FIXMEThefoll
?博客主页：https://xiaoy.blog.csdn.net?本文由呆呆敲代码的小Y原创，首发于CSDN??学习专栏推荐：Unity系统学习专栏?游戏制作专栏推荐：游戏制作?Unity实战100例专栏推荐：Unity实战100例教程?欢迎点赞?收藏⭐留言?如有错误敬请指正！?未来很长，值得我们全力奔赴更美好的生活✨------------------❤️分割线❤️-------------------------
MIMO技术的优缺点优点通过下面三个增益来总体概括：阵列增益。阵列增益是指由于接收机通过对接收信号的相干合并而活得的平均SNR的提高。在发射机不知道信道信息的情况下，MIMO系统可以获得的阵列增益与接收天线数成正比复用增益。在采用空间复用方案的MIMO系统中，可以获得复用增益，即信道容量成倍增加。信道容量的增加与min(Nt,Nr)成正比分集增益。在采用空间分集方案的MIMO系统中，可以获得分集增益，即可靠性性能的改善。分集增益用独立衰落支路数来描述，即分集指数。在使用了空时编码的MIMO系统中，由于接收天线或发射天线之间的间距较远，可认为它们各自的大尺度衰落是相互独立的，因此分布式MIMO
我几天前在我的rubyonrails2.3.2上安装了Sphinx和Thinking-Sphinx，基本搜索效果很好。这意味着，没有任何条件。现在，我想用一些条件过滤搜索。我有公告模型，索引如下所示:define_indexdoindexestitle,:as=>:title,:sortable=>trueindexesdescription,:as=>:description,:sortable=>trueend也许我错了，但我注意到只有当我将:sortable=>true语法添加到这些属性时，我才能将它们用作搜索条件。否则它找不到任何东西。现在，我还在使用acts_as_tag
寻找有用的ruby的好网站是什么？ 最佳答案 AgileWebDevelopment列出插件(虽然不是rubygems，我不确定为什么)，并允许人们对它们进行评级。RubyToolbox按类别列出gem并比较它们的受欢迎程度。Rubygems有一个搜索框。StackOverflow对最有用的rails插件和rubygems有疑问。 关于ruby-如何搜索有用的ruby，我们在StackOverflow上找到一个类似的问题： https://stacko
假设您编写了一个类Sup，我决定将其扩展为SubSup。我不仅需要了解你发布的接口(interface)，还需要了解你的私有(private)字段。见证这次失败:classSupdefinitialize@privateField="fromsup"enddefgetXreturn@privateFieldendendclassSub问题是，解决这个问题的正确方法是什么？看起来子类应该能够使用它想要的任何字段而不会弄乱父类(superclass)。编辑:equivalentexampleinJava返回"fromSup"，这也是它应该产生的答案。 最佳答案