ES基础知识-笔记
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2022-05-01 17:13:31
索引 索引是由英文小写字母组成，且不含中划线。...
elasticsearch-head启动：
npm run start
基本概念
索引
含有相同属性的文档的集合。
索引是由英文小写字母组成，且不含中划线。
类型
索引可以定义一个或多个类型，文档必须属于一个类型。
文档
文档是可以被索引的基本数据单位。
分片
每个索引都有多个分片，每个分片都是一个lucene索引。
备份
拷贝一份分片就完成了分片的备份。
基本用法
api的基本格式
http://<ip>:<port>/<索引>/<类型>/<文档id>
使用put方法创建索引：
PUT http://localhost:9200/people
创建索引的参数：
{
"settings":{
"number_of_shards":3,
"number_of_replicas":1
},
"mappings":{
"man":{
"properties":{
"name":{
"type":"text"
},
"country":{
"type":"keyword"
},
"age":{
"type":"integer"
},
"date":{
"type":"date",
"format":"yyyy-MM-dd HH:mm:ss || yyyy-MM-dd || epoch_millis"
}
}
}
}
}
注意的是elasticsearch6只支持一个索引创建一种类型，不支持一个索引创建多种类型。
插入
指定文档id插入：
PUT http://localhost:9200/people/man/1
{
"name":"Robb",
"country":"wolf",
"age":19,
"date":"1987-03-29"
}
返回结果：
{
"_index": "people",
"_type": "man",
"_id": "1",
"_version": 1,
"result": "created",
"_shards": {
"total": 2,
"successful": 2,
"failed": 0
},
"_seq_no": 0,
"_primary_term": 1
}
不指定文档id插入：
POST http://localhost:9200/people/man/
{
"name":"Talisha",
"country":"free",
"age":18,
"date":"1989-03-29"
}
返回结果：
{
"_index": "people",
"_type": "man",
"_id": "hDT0q2YB6miiGVIFvpyC",
"_version": 1,
"result": "created",
"_shards": {
"total": 2,
"successful": 2,
"failed": 0
},
"_seq_no": 0,
"_primary_term": 1
}
修改
直接修改，指定id
POST http://localhost:9200/people/man/1/_update
{
"doc":{
"name":"fire"
}
}
返回结果：
{
"_index": "people",
"_type": "man",
"_id": "1",
"_version": 2,
"result": "updated",
"_shards": {
"total": 2,
"successful": 2,
"failed": 0
},
"_seq_no": 1,
"_primary_term": 3
}
脚本修改：
年龄+10
POST http://localhost:9200/people/man/1/_update
{
"script":{
"lang":"painless",
"inline":"ctx._source.age += 10"
}
}
返回结果：
{
"_index": "people",
"_type": "man",
"_id": "1",
"_version": 3,
"result": "updated",
"_shards": {
"total": 2,
"successful": 2,
"failed": 0
},
"_seq_no": 2,
"_primary_term": 3
}
在修改部分还可以使用外部参数：
{
"script":{
"lang":"painless",
"inline":"ctx._source.age = params.age",
"params":{
"age":19
}
}
}
删除
删除索引people中类型为man中id为1的文档。
DELETE http://localhost:9200/people/man/1
返回结果：
{
"_index": "people",
"_type": "man",
"_id": "1",
"_version": 5,
"result": "deleted",
"_shards": {
"total": 2,
"successful": 2,
"failed": 0
},
"_seq_no": 4,
"_primary_term": 4
}
删除索引book
DELETE http://localhost:9200/book
返回结果：
{
"acknowledged": true
}
查询
简单查询
新建索引：
PUT http://localhost:9200/novel
{
"mappings":{
"swords":{
"properties":{
"title":{
"type":"text"
},
"author":{
"type":"keyword"
},
"word_count":{
"type":"integer"
},
"publish_date":{
"type":"date",
"format":"yyyy-MM-dd HH:mm:ss||yyyy-MM-dd||epoch_millis"
}
}
}
}
}
插入数据：
PUT http://localhost:9200/novel/swords/11
{
"title":"七十二变",
"author":"孙悟空",
"word_count":1000,
"publish_date":"2000-10-01"
}
插入结果：查询全部
POST http://localhost:9200/novel/_search
{
"query":{
"match_all":{
}
}
}
分页：
{
"query":{
"match_all":{
}
},
"from":1,
"size":2
}
条件查询
根据条件查询：
{
"query":{
"match":{
"title":"ElasticSearch"
}
}
}
返回结果：
{
"took": 89,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"skipped": 0,
"failed": 0
},
"hits": {
"total": 3,
"max_score": 0.86312973,
"hits": [
{
"_index": "novel",
"_type": "swords",
"_id": "4",
"_score": 0.86312973,
"_source": {
"title": "ElasticSearch大法好",
"author": "李四",
"word_count": 1000,
"publish_date": "2017-08-01"
}
},
{
"_index": "novel",
"_type": "swords",
"_id": "8",
"_score": 0.6682933,
"_source": {
"title": "ElasticSearch入门",
"author": "瓦力",
"word_count": 3000,
"publish_date": "2017-08-20"
}
},
{
"_index": "novel",
"_type": "swords",
"_id": "9",
"_score": 0.6682933,
"_source": {
"title": "ElasticSearch精通",
"author": "很胖的瓦力",
"word_count": 3000,
"publish_date": "2017-08-15"
}
}
]
}
}
带排序的条件查询：
{
"query":{
"match":{
"title":"ElasticSearch"
}
},
"sort":{
"publish_date":{"order":"desc"}
}
}
返回结果：
{
"took": 414,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"skipped": 0,
"failed": 0
},
"hits": {
"total": 3,
"max_score": null,
"hits": [
{
"_index": "novel",
"_type": "swords",
"_id": "8",
"_score": null,
"_source": {
"title": "ElasticSearch入门",
"author": "瓦力",
"word_count": 3000,
"publish_date": "2017-08-20"
},
"sort": [
1503187200000
]
},
{
"_index": "novel",
"_type": "swords",
"_id": "9",
"_score": null,
"_source": {
"title": "ElasticSearch精通",
"author": "很胖的瓦力",
"word_count": 3000,
"publish_date": "2017-08-15"
},
"sort": [
1502755200000
]
},
{
"_index": "novel",
"_type": "swords",
"_id": "4",
"_score": null,
"_source": {
"title": "ElasticSearch大法好",
"author": "李四",
"word_count": 1000,
"publish_date": "2017-08-01"
},
"sort": [
1501545600000
]
}
]
}
}
聚合查询
单条件聚合：
{
"aggs": {
"group_by_word_count": {
"terms": {
"field":"word_count"
}
}
}
}
返回结果：
{
"took": 201,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"skipped": 0,
"failed": 0
},
"hits": {
"total": 11,
"max_score": 1,
"hits": [
{
"_index": "novel",
"_type": "swords",
"_id": "5",
"_score": 1,
"_source": {
"title": "菜谱",
"author": "王五",
"word_count": 5000,
"publish_date": "2002-10-01"
}
},
。。。
,
{
"_index": "novel",
"_type": "swords",
"_id": "3",
"_score": 1,
"_source": {
"title": "Python入门",
"author": "张四",
"word_count": 2000,
"publish_date": "2005-10-01"
}
}
]
},
"aggregations": {
"group_by_word_count": {
"doc_count_error_upper_bound": 0,
"sum_other_doc_count": 0,
"buckets": [
{
"key": 1000,
"doc_count": 5
},
{
"key": 2000,
"doc_count": 2
},
{
"key": 3000,
"doc_count": 2
},
{
"key": 5000,
"doc_count": 1
},
{
"key": 10000,
"doc_count": 1
}
]
}
}
}
多条件聚合：
{
"aggs": {
"group_by_word_count": {
"terms": {
"field":"word_count"
}
},
"group_by_publish_date": {
"terms": {
"field":"publish_date"
}
}
}
}
关键结果信息：
"aggregations": {
"group_by_publish_date": {
"doc_count_error_upper_bound": 0,
"sum_other_doc_count": 0,
"buckets": [
{
"key": 970358400000,
"key_as_string": "2000-10-01 00:00:00",
"doc_count": 4
},
{
"key": 852076800000,
"key_as_string": "1997-01-01 00:00:00",
"doc_count": 2
},
{
"key": 1033430400000,
"key_as_string": "2002-10-01 00:00:00",
"doc_count": 1
},
{
"key": 1128124800000,
"key_as_string": "2005-10-01 00:00:00",
"doc_count": 1
},
{
"key": 1501545600000,
"key_as_string": "2017-08-01 00:00:00",
"doc_count": 1
},
{
"key": 1502755200000,
"key_as_string": "2017-08-15 00:00:00",
"doc_count": 1
},
{
"key": 1503187200000,
"key_as_string": "2017-08-20 00:00:00",
"doc_count": 1
}
]
},
"group_by_word_count": {
"doc_count_error_upper_bound": 0,
"sum_other_doc_count": 0,
"buckets": [
{
"key": 1000,
"doc_count": 5
},
{
"key": 2000,
"doc_count": 2
},
{
"key": 3000,
"doc_count": 2
},
{
"key": 5000,
"doc_count": 1
},
{
"key": 10000,
"doc_count": 1
}
]
}
}
功能函数：
{
"aggs": {
"grades_word_count": {
"stats": {
"field":"word_count"
}
}
}
}
关键返回信息：
"aggregations": {
"grades_word_count": {
"count": 11,
"min": 1000,
"max": 10000,
"avg": 2727.2727272727275,
"sum": 30000
}
}
高级查询
query
子条件查询
特定字段查询所指特定值
Query context
在查询的过程中，除了判断文档是否满足查询条件外，ES还会计算一个_score来标识匹配的程度，旨在判断目标文档和查询条件匹配的有多好。
全文本查询
针对文本类型的数据
普通查询：模糊查询，会分词查询
POST http://localhost:9200/novel/_search
{
"query":{
"match":{
"title":"ElasticSearch入门"
}
}
}
结果：使用习语查询可解决这个问题：
{
"query":{
"match_phrase":{
"title":"ElasticSearch入门"
}
}
}
结果：一个值在多个字段中存在的查询：
{
"query":{
"multi_match":{
"query":"瓦力",
"fields":["author","title"]
}
}
}
语法查询：存在语法逻辑
{
"query":{
"query_string":{
"query":"(ElasticSearch and 大法) or Python"
}
}
}
{
"query":{
"query_string":{
"query":"瓦力 or ElasticSearch",
"fields":["author", "title"]
}
}
}
字段级别的查询
针对结构化得数据，如数字、日期等。
字段查询：
{
"query":{
"term":{
"author":"瓦力"
}
}
}
范围查询：
{
"query":{
"range":{
"word_count":{
"gt":1000,
"lte":2000
}
}
}
}
时间范围查询：
{
"query":{
"range":{
"publish_date":{
"gt":"2017-01-01",
"lte":"2017-12-31"
}
}
}
}
子条件查询
Filter context
在查询过程中，只判断该文档是否满足条件，只有YES或NO。
{
"query":{
"bool":{
"filter":{
"term":{
"word_count":1000
}
}
}
}
}
filter需要结合bool使用。
复合条件查询
以一定的逻辑组合子查询
固定查询分数
{
"query":{
"constant_score":{
"filter":{
"match":{
"title":"ElasticSearch"
}
}
}
}
}
{
"query":{
"constant_score":{
"filter":{
"match":{
"title":"ElasticSearch"
}
},
"boost":2
}
}
}
多个条件，或（should）：
{
"query":{
"bool":{
"should":[
{
"match":{
"author":"瓦力"
}
},
{
"match":{
"title":"ElasticSearch"
}
}
]
}
}
}
多个条件，与（must）：
{
"query":{
"bool":{
"must":[
{
"match":{
"author":"瓦力"
}
},
{
"match":{
"title":"ElasticSearch"
}
}
]
}
}
}
先条件，后过滤：
{
"query": {
"bool": {
"must": [
{
"match": {
"author": "瓦力"
}
},
{
"match": {
"title": "ElasticSearch"
}
}
],
"filter": [
{
"match": {
"word_count": 3000
}
}
]
}
}
}
排除：
{
"query": {
"bool": {
"must_not":{
"term":{
"author":"瓦力"
}
}
}
}
}
本文地址：https://blog.csdn.net/YaxiongJiang/article/details/82729839
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