elasticsearch文档操作

• 1、创建文档
• 2、更新文档
• 3、删除文档
• 4、查看文档

POST   http://127.0.0.1:9200/students/_doc/1001

指定Id的情况下，既可以用POST请求也可以用PUT请求，在请求的Body里面添加JSON文档：

{
    "userId": 1001,
    "userName": "Nancy",
    "age": 24,
    "hobby": "游泳,羽毛球，足球"
}

返回结果为：

{
    "_index": "students",
    "_type": "_doc",
    "_id": "1001",
    "_version": 1,
    "result": "created",
    "_shards": {
        "total": 2,
        "successful": 1,
        "failed": 0
    },
    "_seq_no": 0,
    "_primary_term": 1
}

不指定Id的情况下，使用PUT请求时，会报以下错误：

{
    "error": "Incorrect HTTP method for uri [/students/_doc] and method [PUT], allowed: [POST]",
    "status": 405
}

更新文档有两种方式，一种是全量所有字段进行覆盖更新，另一种是指定需要修改的字段进行更新：

• 全量所有字段覆盖更新

PUT   http://127.0.0.1:9200/students/_doc/1001

将Nancy的兴趣爱好hobby字段，删掉足球的爱好，在请求的Body里面添加JSON文档：

{
    "userId": 1001,
    "userName": "Nancy",
    "age": 24,
    "hobby": "游泳,羽毛球"
}

返回结果为：

{
    "_index": "students",
    "_type": "_doc",
    "_id": "1001",
    "_version": 2,
    "result": "updated",
    "_shards": {
        "total": 2,
        "successful": 1,
        "failed": 0
    },
    "_seq_no": 1,
    "_primary_term": 1
}

• 增量只更新需要修改的字段

POST   http://127.0.0.1:9200/students/_update/1001

请求的Body里的内容为：

{
	"doc": {
		"hobby": "游泳,羽毛球",
		"age": 25
	}
}

_upadte表示请求的操作为更新，后面跟的为文档的id,即可完成对应的字段更新。

es删除一个文档不会立即从磁盘上移除，它只是被标记成已删除（逻辑删除）

• 不带条件，根据id来删除

DELETE   http://127.0.0.1:9200/students/_doc/1001

返回结果为：

{
    "_index": "students",
    "_type": "_doc",
    "_id": "1001",
    "_version": 6,
    "result": "deleted",
    "_shards": {
        "total": 2,
        "successful": 1,
        "failed": 0
    },
    "_seq_no": 5,
    "_primary_term": 1
}

若对一个不存在的文档进行删除，在返回结果的result字段会显示not_found，表示文档未查找到。

{
    "_index": "students",
    "_type": "_doc",
    "_id": "1008",
    "_version": 1,
    "result": "not_found",
    "_shards": {
        "total": 2,
        "successful": 1,
        "failed": 0
    },
    "_seq_no": 11,
    "_primary_term": 2
}

• 带条件，根据条件来删除

POST  http://127.0.0.1:9200/students/_delete_by_query

请求体：

{
    "query": {
        "match": {
            "age": 24
        }
    }
}

返回结果：

{
    "took": 180,
    "timed_out": false,
    "total": 2,
    "deleted": 2,
    "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": []
}

查看文档时候，需要指明文档的唯一表示，类似于数据库的唯一主键。

GET   http://127.0.0.1:9200/students/_doc/1002

返回结果：

{
    "_index": "students",
    "_type": "_doc",
    "_id": "1002",
    "_version": 1,
    "_seq_no": 10,
    "_primary_term": 2,
    "found": true,
    "_source": {
        "userId": 1002,
        "userName": "Tom",
        "age": 24,
        "hobby": "游泳,足球"
    }
}

查看一个已被删除或者不存在的文档时，在返回结果的found字段会用false表示未找到。

{
    "_index": "students",
    "_type": "_doc",
    "_id": "1008",
    "found": false
}

查询一个索引下的所有文档：

GET    http://127.0.0.1:9200/students/_search

返回结果：

{
    "took": 4,
    "timed_out": false,
    "_shards": {
        "total": 1,
        "successful": 1,
        "skipped": 0,
        "failed": 0
    },
    "hits": {
        "total": {
            "value": 1,
            "relation": "eq"
        },
        "max_score": 1.0,
        "hits": [
            {
                "_index": "students",
                "_type": "_doc",
                "_id": "1002",
                "_score": 1.0,
                "_source": {
                    "userId": 1002,
                    "userName": "Tom",
                    "age": 24,
                    "hobby": "游泳,足球"
                }
            }
        ]
    }
}