Elasticsearch篇之Search API介绍

1 SearchAPI概览

实现对es中存储的数据进行查询分析，endpoint为_search，如下所示：

查询主要有两种形式

2 URISearch详解与演示

通过url query参数来实现搜索，常用参数如下：

• q指定查询的语句，语法为Query String Syntax
• df q中不指定字段时默认查询的字段，如果不指定，es会查询所有字段
• sort 排序
• timeout 指定超时时间，默认不超时
• from、size 用于分页
  
• term 与 phrase
  • alfred way 等效于 alfred or way
• “alfred way”词语查询，要求先后排序
• 泛查询
  • alfred 等效于在所有字段中去匹配该term
• 指定字段
  • name:aflred
• Group分组设定，使用括号指定匹配的规则
  • (quick OR brown)AND fox
  • status:(active OR pending) title:(full text search)
    创建索引，生成测试文档

PUT my_index_search
{
  "settings": 
  {
    "number_of_shards": "5",
    "number_of_replicas": "0"
  }
}
POST my_index_search/doc/_bulk
{"index":{"_id": "1"}}
{"username": "alfred way","job": "java engineer","age": 18,"birth": "1990-01-02","isMarried":false}
{"index":{"_id": "2"}}
{"username": "alfred","job": "java senior and java specialist","age": 28,"birth": "1980-05-07","isMarried":true}
{"index":{"_id": "3"}}
{"username": "lee","job": "java and ruby engineer","age": 22,"birth": "1985-08-07","isMarried":false}
{"index":{"_id": "4"}}
{"username": "alfred junior way","job": "ruby engineer","age": 23,"birth": "1989-08-02","isMarried":false}

# 查询所有字段中有alfred的文档
GET my_index_search/_search?q=alfred
# 设置profile可以看具体的查询语句
GET my_index_search/_search?q=alfred
{
  "profile": true
}
GET my_index_search/_search?q=username:alfred
GET my_index_search/_search?q=username:alfred
{
  "profile": true
}
# username:alfred和way是OR的关系
GET my_index_search/_search?q=username:alfred way
{
  "profile": true
}
# PhraseQuery词语的查询
GET my_index_search/_search?q=username:"alfred way"
{
  "profile": true
}
# "description": "username:alfred username:way" 下面描述
GET my_index_search/_search?q=username:(alfred way)
{
  "profile": true
}

• 布尔操作符
• AND(&&) OR(||) NOT(!)
• name:(tom NOT lee)
• 注意大写，不能小写
• + - 分别对应must和must_not
• name:(tom +lee -alfred) 或者 name:((lee && !alfred)||(tome && lee && !alfred))
• + 在url中会被解析为空格，要使用encode后才可以，为%2B

GET my_index_search/_search?q=username:alfred AND way
{
  "profile": true
}
GET my_index_search/_search?q=username:(alfred AND way)
{
  "profile": true
}
GET my_index_search/_search?q=username:(alfred NOT way)
{
  "profile": true
}
GET my_index_search/_search?q=username:(alfred +way)
{
  "profile": true
}
GET my_index_search/_search?q=username:(alfred %2Bway)
{
  "profile": true
}

• 范围查询，支持数值和日期
  • 区间写法，闭区间用[]，开区间{}
    • age:[1 TO 10]意为 1<=age<=10
    • age:[1 TO 10}意为 1<=age<10
    • age:[1 TO]意为 age>=1
    • age:{* TO 10]意为age<=10
  • 算术符号写法
    • age:>=1
    • age:(>=1 && <=10)或者 age:(+>=1 +<=10)

GET my_index_search/_search?q=username:alfred age:>20
GET my_index_search/_search?q=username:alfred AND age:>20
GET my_index_search/_search?q=birth:(>1980 AND <1990)

• 通配符查询
• ？ 代表1个字符， * 代表0或多个字符
  • name:t?m
  • name:tom*
  • name:t*m
• 通配符匹配执行效率低，且占用较多内存，不建议使用
• 如无特殊需求，不要将？/ * 放在最前面

GET my_index_search/_search?q=username:alf*

• 正则表达式匹配

GET my_index_search/_search?q=username:/[a]?l.*/

• 模糊匹配fuzzy query
• name：roam~1
• 匹配roam差1个character的词，比如foam、roams等
• 近似度查询proximity search
• “fox quick”~5
• 以term为单位进行差异比较，比如“quick fox” “quick brown fox”都会被匹配

GET my_index_search/_search?q=username:alfed~1
GET my_index_search/_search?q=job:"java engineer"~2

3 QueryDSL简介

4 字段类查询简介及match-query

5 相关性算分

6 match-phrase-query_音频

7 query-string-query

8 simple-query-string-query

9 term-terms-query

10 range-query

11 复合查询介绍及ConstantScore

12 bool-query

13 count-and-source-filtering