ElasticSearch

ES|QL: 
一方面：ESQL == Elasticsearch SQL。
另一方面：ESQL = ES + QL， ES = Elasticsearch， QL 等于 SQL。
再有， | 代表过滤的意思，也类似 linux 命令行。

为了满足 ES|QL 的功能和性能要求，必须构建全新的计算架构。ES|QL 的搜索、聚合和转换功能直接在 Elasticsearch 内部执行，
而不是转换为 Query DSL 执行。这种设计使 ES|QL 性能高效且多功能。

ES|QL 执行引擎针对性能优化，采用分块而非逐行操作，专注于向量化、缓存局部性、专业化和多线程处理，
与现有的 Elasticsearch 聚合框架具有不同的性能特征。

https://www.elastic.co/blog/loading-wikipedia |Loading Wikipedia's Search Index For Testing
https://www.youtube.com/watch?v=yHjzykn7nuw |Elasticseach Vector Database RAG Demo
https://www.elastic.co/docs/reference/elasticsearch/clients/python/examples |Examples
https://www.elastic.co/docs/extend/integrations/quick-start |Quick start: Sample integrationo
https://www.elastic.co/docs/manage-data/ingest/sample-data
https://www.elastic.co/docs/explore-analyze/transforms/transform-examples |Transforms examples

ElasticSearch详解

CentOS 7下安装部署Elasticsearch7.3.1

ElasticSearch 索引查询使用指南——详细版

ik的es插件地址

ElasticSearch 中文分词器 es-ik，Ansj，hanlp 对比

全文搜索引擎 Elasticsearch 入门教程

ES简单实用DSL查询

Getting started with the Elastic Stack and Docker Compose

Docker elk(elasticsearch logstash kibana)

Ingest Data into the Elastic Stack with Logstash and Filebeat

Sending Logs to Elasticsearch using Filebeat and Logstash.

使用Filebeat+Kafka+Logstash+Elasticsearch构建日志分析系统

大模型RAG实战｜向量数据库：Elasticsearch实现混合检索（附完整代码）

Implementing Agentic RAG using Elasticsearch & Langchain - yt

RAG

RAG and Elasticsearch: Bringing Context to Search - yt

RAG Application using OpenAI and ElasticSearch as Vector DB

RAG on Elastic - reddit

安装

下载地址：
https://www.elastic.co/cn/downloads/elasticsearch
es:a-80

groupadd esearch                    创建esearch组
useradd -g esearch els              创建ela用户，并且加入ela组
passwd ela                          为ela用户设定登录密码
vim /etc/sudoers)
    root    ALL=(ALL)  ALL
    ela    ALL=(ALL)  ALL
    
chown es:esearch /home/es/data/

su es
cd /usr/local/Elasticsearch/bin
./elasticsearch7 -d                 后台运行模式
jps                                 查看后台进程
kill -9                             终止后台运行


curl localhost:9200/
查看所有索引
curl localhost:9200/_cat/indices
查看字段类型
curl localhost:9200/site_search/_mapping?pretty
curl localhost:9200/site_search/_search?pretty'-d' {
    "from": 0,
    "size": 30,
    "_soruce": {"excludes": ["content']},
    "query": {
        "filtered": {
            "filter": { "terms": ["_id": []]}
        },
        "sort": {"published": {"order": "desc"}}
    }
}

curl -XPOST localhost:9200/site_search/_search?pretty -d '
{
    "from": 0,
    "size": 8,
    "_source": {"excludes": ["content"]},
    "query": { "match_all": {}},
    "sort": {"published": {"order": "desc"}}
}'

curl -XPOST localhost:9200/site_search/_search?pretty -d '
{
    "from": 0,
    "size": 8,
    "_source": {"excludes": ["content"]},
    "query": {
        "filtered": {
           "filter": {"terms": {"_id": ["393871","393870"]}}
        }
    },
    "sort": {"published": {"order": "desc"}}
}'