es学习(二)：基本操作

集群健康

请求

GET http://192.168.247.8:9200/_cluster/health

结果

{
    "cluster_name": "kevin-elasticsearch",
    "status": "green",
    "timed_out": false,
    "number_of_nodes": 1,
    "number_of_data_nodes": 1,
    "active_primary_shards": 5,
    "active_shards": 5,
    "relocating_shards": 0,
    "initializing_shards": 0,
    "unassigned_shards": 0,
    "delayed_unassigned_shards": 0,
    "number_of_pending_tasks": 0,
    "number_of_in_flight_fetch": 0,
    "task_max_waiting_in_queue_millis": 0,
    "active_shards_percent_as_number": 100.0
}

创建索引

请求

PUT http://192.168.247.8:9200/index_str

{
    "settings": {
        "index": {
            "number_of_shards": "2",
            "number_of_replicas": "0"
        }
    }
}

结果：

{
    "acknowledged": true,
    "shards_acknowledged": true,
    "index": "index_str"
}

查看索引

请求

GET http://192.168.247.8:9200/_cat/indices?v

结果

health status index      uuid                   pri rep docs.count docs.deleted store.size pri.store.size
green  open   index_demo xUOiKc5QT5-UWWcJjqRkIw   5   0          0            0      1.3kb          1.3kb
green  open   index_str  BniDy5eJQ26Qg26oRbz_Rg   2   0          0            0       460b           460b

删除索引

DELETE  http://192.168.247.8:9200/index_str

结果

{
    "acknowledged": true
}

索引的mappings映射

索引分词概念

index：默认true，设置为false的话，那么这个字段就不会被索引

创建索引的同时创建mappings

请求

PUT http://192.168.247.8:9200/index_str

{
    "mappings": {
        "properties": {
            "realname": {
            	"type": "text",
            	"index": true
            },
            "username": {
            	"type": "keyword",
            	"index": false
            }
        }
    }
}

返回

{
    "acknowledged": true,
    "shards_acknowledged": true,
    "index": "index_str"
}

查看分词效果

请求

GET http://192.168.247.8:9200/index_str/_analyze

{
	"field": "realname",
	"text": "kevin is god"
}

结果

{
    "tokens": [
        {
            "token": "kevin",
            "start_offset": 0,
            "end_offset": 5,
            "type": "<ALPHANUM>",
            "position": 0
        },
        {
            "token": "is",
            "start_offset": 6,
            "end_offset": 8,
            "type": "<ALPHANUM>",
            "position": 1
        },
        {
            "token": "god",
            "start_offset": 9,
            "end_offset": 12,
            "type": "<ALPHANUM>",
            "position": 2
        }
    ]
}

修改mappings

请求

POST http://192.168.247.8:9200/index_str/_mapping

{
    "properties": {
        "name": {
        	   "type": "long"
        }
    }
}

结果

{
    "acknowledged": true
}

某个属性一旦被建立，就不能修改了，但是可以新增额外属性

为已存在的索引创建mappings

请求

POST http://192.168.247.8:9200/index_str/_mapping


{
    "properties": {
        "id": {
        	"type": "long"
        },
        "age": {
        	"type": "integer"
        },
        "nickname": {
            "type": "keyword"
        }
    }
}

结果

{
    "acknowledged": true
}

主要数据类型

• text, keyword
• long, integer, short, byte
• double, float
• boolean
• date
• object
• 数组不能混，类型一致

字符串

• text：文字类需要被分词被倒排索引的内容，比如商品名称，商品详情，商品介绍，使用text。
• keyword：不会被分词，不会被倒排索引，直接匹配搜索，比如订单状态，用户qq，微信号，手机号等，这些精确匹配，无需分词。

添加文档数据

POST /my_doc/_doc/1 -> {索引名}/_doc/{索引ID}（是指索引在es中的id，而不是这条记录的id，比如记录的id从数据库来是1001，并不是这个。如果不写，则自动生成一个字符串。建议和数据id保持一致> ）

{
    "id": 1001,
    "name": "kevin-1",
    "desc": "kevin is very good, 渣渣猿非常牛！",
    "create_date": "2019-12-24"
}

返回

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

文档修改

局部修改

请求

POST  http://192.168.247.8:9200/my_doc/_doc/2/_update

{
    "doc":{
    	"name":"maomao"
    }
}

返回

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

全量替换

请求

PUT  http://192.168.247.8:9200/my_doc/_doc/2

{
    "id": 1002,
    "name": "kevin_2",
    "desc": "我是渣渣猿,紧紧抱住坤哥大腿！",
    "create_date": "2020-02-04"
}

结果

{
    "_index": "my_doc",
    "_type": "_doc",
    "_id": "2",
    "_version": 3,
    "result": "updated",
    "_shards": {
        "total": 1,
        "successful": 1,
        "failed": 0
    },
    "_seq_no": 2,
    "_primary_term": 1
}

注意：每次修改后，version都会更改

删除文档

请求

DELETE  http://192.168.247.8:9200/my_doc/_doc/2

返回

{
    "_index": "my_doc",
    "_type": "_doc",
    "_id": "2",
    "_version": 4,
    "result": "deleted",
    "_shards": {
        "total": 1,
        "successful": 1,
        "failed": 0
    },
    "_seq_no": 3,
    "_primary_term": 1
}

查询

查询文档

GET http://192.168.247.8:9200/my_doc/_doc/1

# 结果

{
    "_index": "my_doc",
    "_type": "_doc",
    "_id": "1",
    "_version": 2,
    "_seq_no": 1,
    "_primary_term": 1,
    "found": true,
    "_source": {
        "id": 1001,
        "name": "毛毛",
        "desc": "kevin is very good, 渣渣猿非常牛！",
        "create_date": "2019-12-24"
    }
}

GET http://192.168.247.8:9200/my_doc/_doc/_search

# 结果

{
    "took": 17,
    "timed_out": false,
    "_shards": {
        "total": 5,
        "successful": 5,
        "skipped": 0,
        "failed": 0
    },
    "hits": {
        "total": {
            "value": 1,
            "relation": "eq"
        },
        "max_score": 1.0,
        "hits": [
            {
                "_index": "my_doc",
                "_type": "_doc",
                "_id": "1",
                "_score": 1.0,
                "_source": {
                    "id": 1001,
                    "name": "毛毛",
                    "desc": "kevin is very good, 渣渣猿非常牛！",
                    "create_date": "2019-12-24"
                }
            }
        ]
    }
}

• _index：文档数据所属那个索引，理解为数据库的某张表即可。
• _type：文档数据属于哪个类型，新版本使用_doc。
• _id：文档数据的唯一标识，类似数据库中某张表的主键。可以自动生成或者手动指定。
• _score：查询相关度，是否契合用户匹配，分数越高用户的搜索体验越高。
• _version：版本号。
• _source：文档数据，json格式。

定制结果集

GET  http://192.168.247.8:9200/my_doc/_doc/1?_source=id,name

# 结果

{
    "_index": "my_doc",
    "_type": "_doc",
    "_id": "1",
    "_version": 2,
    "_seq_no": 1,
    "_primary_term": 1,
    "found": true,
    "_source": {
        "name": "毛毛",
        "id": 1001
    }
}

GET /index_demo/_doc/_search?_source=id,name

判断文档是否存在

HEAD /index_demo/_doc/1


查看返回状态

好了，这篇先学习到这。玩的开心！