ES 基本概念和基本操作
目录
说明
本文来自于博客园，用以记录通过访问接口的方式来访问 es 的简单操作。
大部分源自原文，但是因为ES版本不同，做了部分内容修改。此文ES版本7.6
es & mysql 概念对比表。type类型将会在以后的版本中被移除
es 接口访问示例
1.文档操作
1.索引操作
建立索引就相当于创建数据库，创建数据库就要创建表结构。es的建立索引就是创建数据库这一操作。
创建索引：
PUT http://localhost:9200/zq_test # 建立一个名为 zq_test 的索引
返回结果：
{
"acknowledged": true,
"shards_acknowledged": true,
"index": "zq_test"
}
获取索引
GET http://localhost:9200/zq_test
返回结果:
{
"zq_test": {
"aliases": {},
"mappings": {},
"settings": {
"index": {
"creation_date": "1623325887846",
"number_of_shards": "1",
"number_of_replicas": "1",
"uuid": "V1Ewmh1sSAmPwtiUqgfY-Q",
"version": {
"created": "7060099"
},
"provided_name": "zq_test"
}
}
}
}
2.设置mapping
设置Index的Mapping，也就是设置数据的表结构
删除索引：
DELEET http://localhost:9200/zq_test
返回：
{
"acknowledged": true
}
重新创建索引：
PUT http://localhost:9200/zq_test # 并提交一下参数，content-type：application/json
{
"mappings": {
"properties": {
"name": {
"type": "text",
"fields": {
"keyword": {
"type": "keyword",
"ignore_above": 256
}
}
},
"age": {
"type": "long",
"index": true
},
"gender": {
"type": "keyword"
}
}
}
}
返回：
{
"acknowledged": true,
"shards_acknowledged": true,
"index": "zq_test"
}
name：text类型，会进行分词，支持模糊检索。
name.keyword : 这相当于是嵌套了一个字段，keyword类型，只能精确匹配，不支持分词。超过256字符长度不索引，也就没法搜索到。
age：long类型，支持精确匹配。index 为 true 才可以匹配
gender：keyword类型，只能精确匹配，不支持分词。
3.插入文档
插入文档，即使用接口，将 json 文档放入 es 索引中。
请求必须指定文档的索引名称，唯一的文档 ID, 以及请求体中一个或多个键值对。
PUT http://localhost:9200/zq_test/_doc/2
# json
{
"name": "tom",
"age": 5,
"gender": "man"
}
返回：
{
"_index": "zq_test",
"_type": "_doc",
"_id": "2",
"_version": 1,
"result": "created",
"_shards": {
"total": 2,
"successful": 1,
"failed": 0
},
"_seq_no": 1,
"_primary_term": 1
}
4.获取文档
根据 id 获取文档。
GET http://localhost:9200/zq_test/_doc/1
返回：
{
"_index": "zq_test",
"_type": "_doc",
"_id": "1",
"_version": 1,
"_seq_no": 0,
"_primary_term": 1,
"found": true,
"_source": {
"name": "yezi test",
"age": 25,
"gender": "man"
}
}
5.删除文档
根据 id 删除文档
DELETE http://localhost:9200/zq_test/_doc/2
返回：
{
"_index": "zq_test",
"_type": "_doc",
"_id": "2",
"_version": 2,
"result": "deleted",
"_shards": {
"total": 2,
"successful": 1,
"failed": 0
},
"_seq_no": 2,
"_primary_term": 1
}
加入两个测试数据
PUT http://localhost:9200/zq_test/_doc/3
{
"name": "ceshi01",
"age": 35,
"gender": "man"
}
PUT http://localhost:9200/zq_test/_doc/4
{
"name": "ceshi02",
"age": 40,
"gender": "woman"
}
根据筛选条件删除数据
# 根据年龄删除数据
Post http://localhost:9200/zq_test/_doc/_delete_by_query
# json body
{
"query": {
"match": {
"age": 35
}
}
}
返回:
{
"took": 13,
"timed_out": false,
"total": 1,
"deleted": 1,
"batches": 1,
"version_conflicts": 0,
"noops": 0,
"retries": {
"bulk": 0,
"search": 0
},
"throttled_millis": 0,
"requests_per_second": -1.0,
"throttled_until_millis": 0,
"failures": []
}
可使用
{"query": {"match_all":{}}}的方式删除所有
6.更新文档
覆盖更新(先删除后添加):
更新完成后，可以看到原有 name age gender只剩下 age，相当于删除原有。
Put http://localhost:9200/zq_test/_doc/4
# json body
{
"age": 500
}
返回：
{
"_index": "zq_test",
"_type": "_doc",
"_id": "4",
"_version": 2,
"result": "updated",
"_shards": {
"total": 2,
"successful": 1,
"failed": 0
},
"_seq_no": 3,
"_primary_term": 1
}
部分更新(不删除，更新相应字段) 建议用此
POST http://localhost:9200/zq_test/_doc/4/_update
# json body
{
"doc": {
"age": 10000,
"gender": "aha"
}
}
返回:
{
"_index": "zq_test",
"_type": "_doc",
"_id": "4",
"_version": 6,
"result": "updated",
"_shards": {
"total": 2,
"successful": 1,
"failed": 0
},
"_seq_no": 13,
"_primary_term": 1
}
# 对应的数据如下
{
"_index": "zq_test",
"_type": "_doc",
"_id": "4",
"_version": 6,
"_seq_no": 13,
"_primary_term": 1,
"found": true,
"_source": {
"name": "jerry",
"age": 10000,
"gender": "aha"
}
}
根据查询条件更新
POST http://localhost:9200/zq_test/_doc/_update_by_query
# json body 2021-06-18 18:18 试验失败
{
"script": {
"source": "ctx._source.age=5", # ctx._source 指源文档
"lang": "painless"
},
"query": {
"term": {
"name": "ceshi01"
}
}
}
返回：
{
"_index": "zq_test",
"_type": "_doc",
"_id": "_update_by_query",
"found": false
}
7.批量获取
批量获取文档(不指定索引库)
GET http://localhost:9200/_mget
# json 链接中没有指明索引库，但是在 json body 中进行了指定
{
"docs": [
{
"_index": "zq_test",
"_type": "_doc",
"_id": 4
},
{
"_index": "zq_test_copy",
"_type": "_doc",
"_id": 4
}
]
}
返回：
{
"docs": [
{
"_index": "zq_test",
"_type": "_doc",
"_id": "4",
"_version": 3,
"_seq_no": 4,
"_primary_term": 1,
"found": true,
"_source": {
"name": "jerry",
"age": 500,
"gender": "man"
}
},
{
"_index": "zq_test_copy",
"_type": "_doc",
"_id": "4",
"_version": 2,
"_seq_no": 1,
"_primary_term": 1,
"found": true,
"_source": {
"name": "jerry",
"age": 500,
"gender": "man"
}
}
]
}
批量获取文档(指定索引库或类型)
# 一
GET http://localhost:9200/zq_test/_mget
# json 中指明 _id, 链接中指明 index
{
"docs": [
{
"_id": 4
},
{
"_id": 3
}
]
}
返回：
{
"docs": [
{
"_index": "zq_test",
"_type": "_doc",
"_id": "4",
"_version": 3,
"_seq_no": 4,
"_primary_term": 1,
"found": true,
"_source": {
"name": "jerry",
"age": 500,
"gender": "man"
}
},
{
"_index": "zq_test",
"_type": "_doc",
"_id": "3",
"_version": 1,
"_seq_no": 5,
"_primary_term": 1,
"found": true,
"_source": {
"name": "ceshi01",
"age": 35,
"gender": "man"
}
}
]
}
# 二
GET http://localhost:9200/zq_test/_doc/_mget
# json 中指明 _id, 链接中指明 index 和 _doc
{
"ids": [3, 4]
}
返回:
{
"docs": [
{
"_index": "zq_test",
"_type": "_doc",
"_id": "3",
"_version": 1,
"_seq_no": 5,
"_primary_term": 1,
"found": true,
"_source": {
"name": "ceshi01",
"age": 35,
"gender": "man"
}
},
{
"_index": "zq_test",
"_type": "_doc",
"_id": "4",
"_version": 3,
"_seq_no": 4,
"_primary_term": 1,
"found": true,
"_source": {
"name": "jerry",
"age": 500,
"gender": "man"
}
}
]
}
8.批处理操作
ES允许我们在一次请求中做多种操作，比如在一次请求中同时进行增删改查操作：
批处理操作：
POST http://localhost:9200/_bulk # 下边进行了一个批处理操作，分别包含添加、删除、更新操作，
但是提交的参数必须是一行一行的
json，且结尾必须有换行符，要这样ES才好处理，因为不是标准的json格式，这里PostMan识别json格式错误，但是问题不大。
json body:
{"index": {"_index": "zq_test", "_id": 5}}
{"name": "bulk", "age": 16, "gender": "woman"}
{"delete": {"_id": 5, "_index": "zq_test"}}
{"update": {"_id": 4, "_index": "zq_test"}}
{"doc": {"name": "jiuge", "age": 333, "gender": "sex"}}
# 注意，上面的 json body 必须每行都有换行符，即要多一个空行。另外已经删除的 5 不能 update
返回：
{
"took": 4,
"errors": false,
"items": [
{
"index": {
"_index": "zq_test",
"_type": "_doc",
"_id": "5",
"_version": 16,
"result": "created",
"_shards": {
"total": 2,
"successful": 1,
"failed": 0
},
"_seq_no": 29,
"_primary_term": 1,
"status": 201
}
},
{
"delete": {
"_index": "zq_test",
"_type": "_doc",
"_id": "5",
"_version": 17,
"result": "deleted",
"_shards": {
"total": 2,
"successful": 1,
"failed": 0
},
"_seq_no": 30,
"_primary_term": 1,
"status": 200
}
},
{
"update": {
"_index": "zq_test",
"_type": "_doc",
"_id": "4",
"_version": 7,
"result": "updated",
"_shards": {
"total": 2,
"successful": 1,
"failed": 0
},
"_seq_no": 31,
"_primary_term": 1,
"status": 200
}
}
]
}
9.重建索引
重新建立索引，相当于拷贝一份.
POST http://localhost:9200/_reindex
json body:
{
"source": {
"index": "zq_test"
},
"dest":{
"index": "zq2"
}
}
返回：
{
"took": 184,
"timed_out": false,
"total": 2,
"updated": 0,
"created": 2,
"deleted": 0,
"batches": 1,
"version_conflicts": 0,
"noops": 0,
"retries": {
"bulk": 0,
"search": 0
},
"throttled_millis": 0,
"requests_per_second": -1.0,
"throttled_until_millis": 0,
"failures": []
}
2.查询操作
1.多索引和多类型查询
# 1 查询所有索引下所有类型的数据，查询条件为 name=jiuge
GET http://localhost:9200/_search?q=name:jiuge # 可以不带 _all
# 2 获取所有索引下类型为 _doc 的 数据，查询条件为 name = jiuge
GET http://localhost:9200/_all/_doc/_search?q=name:jiuge
# 3 获取zq_test索引和 zq2 索引下类型为_doc 的数据，查询条件下为 name=jiuge
GET http://localhost:9200/zq_test,zq2/_doc/_search?q=name:jiuge
# *4 获取zq_test 索引下类型为 teacher和student的数据，查询条件为 name=jiuge
GET http://localhost:9200/zq_test/teacher,student/_search?q=name:jiuge # 因为es7 及其之后，type默认为_doc, 且在 es8 后，type 将取消，因此此访问方式仅作参考，不必使用。
返回：
{
"took": 3,
"timed_out": false,
"_shards": {
"total": 16,
"successful": 16,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 2,
"relation": "eq"
},
"max_score": 1.7917595,
"hits": [
{
"_index": "zq_test",
"_type": "_doc",
"_id": "4",
"_score": 1.7917595,
"_source": {
"name": "jiuge",
"age": 333,
"gender": "sex"
}
},
{
"_index": "zq2",
"_type": "_doc",
"_id": "4",
"_score": 0.6931471,
"_source": {
"name": "jiuge",
"age": 333,
"gender": "sex"
}
}
]
}
}
2. 查询字符串查询
通过 GET 访问的方式，在 URL 后面添加查询字符串的方式查询。
GET http://localhost:9200/zq_test/_search?from=0&size=10&q=name:ceshi006 OR name:ceshi007&sort=age:asc&_source=name,age
说明：
- from=0&size=10 : 分页获取
- q=name:ceshi006 OR name:ceshi007: 表示查询 name 为 ceshi006 或 ceshi007 的文档。OR 可以换做 AND
- sort=age:asc：排序，表示按照 age 进行排序。asc 降序， desc 升序
- _source=name,age：投影，选择返回的字段，多个字段用 , 隔开
返回：
{
"took": 0,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 2,
"relation": "eq"
},
"max_score": null,
"hits": [
{
"_index": "zq_test",
"_type": "_doc",
"_id": "6",
"_score": null,
"_source": {
"name": "ceshi006",
"age": 66
},
"sort": [
66
]
},
{
"_index": "zq_test",
"_type": "_doc",
"_id": "7",
"_score": null,
"_source": {
"name": "ceshi007",
"age": 77
},
"sort": [
77
]
}
]
}
}
可使用插入文档的方式放入多个数据供实验. 更多查询参数和语法[点此查看]([Search API | Elasticsearch Guide 7.13] | Elastic)
3. 请求体查询
通过请求体进行查询。
GET http://localhost:9200/zq_test/_search # 也通过 json body
json body:
{
"query":{
"match":{
"name": "ceshi006"
}
},
"sort": [
{
"age": "asc"
}
],
"size": 5,
"from": 0
}
返回：
{
"took": 1,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 1,
"relation": "eq"
},
"max_score": null,
"hits": [
{
"_index": "zq_test",
"_type": "_doc",
"_id": "6",
"_score": null,
"_source": {
"name": "ceshi006",
"age": 66,
"gender": "man"
},
"sort": [
66
]
}
]
}
}
更多操作参数[点此查看]([Request body search | Elasticsearch Guide 7.13] | Elastic)
