elasticsearch学习（五）文档CRUD

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elasticsearch学习（四）kibana安装
https://blog.csdn.net/github_36801273/article/details/151076329?spm=1011.2124.3001.6209

文档CRUD

创建索引

PUT /my-index
{"mappings": {"properties": {"testFieldA": {"type": "text","fields": {"keyword": {"type": "keyword","ignore_above": 256}}},"testFieldB": {"type": "text","fields": {"keyword": {"type": "keyword","ignore_above": 256}}}}}
}

mapping的部分不是必须的，可以通过先创建索引，然后写入数据的方式自动生成mapping

查看索引字段mapping

GET /my-index/_mapping{"my-index": {"mappings": {"properties": {"testFieldA": {"type": "text","fields": {"keyword": {"type": "keyword","ignore_above": 256}}},"testFieldB": {"type": "text","fields": {"keyword": {"type": "keyword","ignore_above": 256}}}}}}
}

更新mapping

POST  /my-index/_mapping
{"properties": {"testFieldC": {"type": "text","fields": {"keyword": {"type": "keyword","ignore_above": 256}}},"testFieldB": {"type": "text","fields": {"keyword": {"type": "keyword","ignore_above": 512}}}}
}

只能新增和更新字段，不能删除字段，删除字段用reindex

删除索引

DELETE /my-index

测试索引是否存在

HEAD /my-index

查看索引字段结构

GET /my-index/_mapping

删除索引

DELETE /my-index

文档命令

创建文档

Index

如果ID不存在，则创建新的，否则删除旧的再创建新的，增加版本号

POST /my-index/_doc
{"id": "park_rocky-mountain","title": "Rocky Mountain","description": "Bisected north to south by the Continental Divide, this portion of the Rockies has ecosystems varying from over 150 riparian lakes to montane and subalpine forests to treeless alpine tundra."
}

Create

// 不指定ID（系统自动生成）
POST /my-index/_doc
{"testFieldA":"testA1","testFieldB":"testB1"
}// 指定ID
POST /my-index/_doc/2
{"testFieldA":"testA2","testFieldB":"testB2"
}

Create与Index的区别

create的文档ID如果已存在，会报失败
index的文档ID不存在，会新建，否则会把原来的删除了再增加

更新文档

POST /my-index/_update/2
{"doc":{"testFieldA":"updateTestA2"} 
}

删除文档

DELETE /my-index/_doc/2

查询文档

支持两种方式：
1 url查询，在url路径中使用查询参数
2 用DSL（Query Domain Specific Language）

简单查询语法

api	作用
/_search	查询集群上所有索引
/{index_name}/_search	查询指定索引
/{index_name1},{index_name2},{…}/_search	查询多个指定索引
/{index_prex}*/_search	查询以{index_prex}为开头的索引

// 指定ID查询
GET /my-index/_doc/2// 查询全量数据
GET /my-index/_search// 查询my开头的索引数据
GET /my*/_search// URL查询
GET /my-index/_search?q=testFieldA:updateTestA2// DSL查询
GET /my-index/_search -H 'Content-Type:application/json' -d
{"query":{"match":{"testFieldA":"updateTestA2"}}
}