ElasticSearch中文分词(IK)

时间:2021-02-12 20:20:13
ElasticSearch常用的很受欢迎的是IK,这里稍微介绍下安装过程及测试过程。
 

1、ElasticSearch官方分词

自带的中文分词器很弱,可以体检下:
[zsz@VS-zsz ~]$ curl -XGET 'http://192.168.31.77:9200/_analyze?analyzer=standard' -d '岁月如梭'

{

    "tokens": [

        {

            "token": "岁",

            "start_offset": 0,

            "end_offset": 1,

            "type": "<IDEOGRAPHIC>",

            "position": 0

        },

        {

            "token": "月",

            "start_offset": 1,

            "end_offset": 2,

            "type": "<IDEOGRAPHIC>",

            "position": 1

        },

        {

            "token": "如",

            "start_offset": 2,

            "end_offset": 3,

            "type": "<IDEOGRAPHIC>",

            "position": 2

        },

        {

            "token": "梭",

            "start_offset": 3,

            "end_offset": 4,

            "type": "<IDEOGRAPHIC>",

            "position": 3

        }

    ]

}
[zsz@VS-zsz ~]$ curl -XGET 'http://192.168.31.77:9200/_analyze?analyzer=standard' -d 'i am an enginner'

{

    "tokens": [

        {

            "token": "i",

            "start_offset": 0,

            "end_offset": 1,

            "type": "<ALPHANUM>",

            "position": 0

        },

        {

            "token": "am",

            "start_offset": 2,

            "end_offset": 4,

            "type": "<ALPHANUM>",

            "position": 1

        },

        {

            "token": "an",

            "start_offset": 5,

            "end_offset": 7,

            "type": "<ALPHANUM>",

            "position": 2

        },

        {

            "token": "enginner",

            "start_offset": 8,

            "end_offset": 16,

            "type": "<ALPHANUM>",

            "position": 3

        }

    ]

}
由此看见,ES的官方中文分词能力较差。
 
2、IK中文分词器
 
2.1、如何你下载的ik是源码半,需要打包该分词器,linux安装maven
tar zxvf apache-maven-3.0.5-bin.tar.gz
mv apache-maven-3.0.5 /usr/local/apache-maven-3.0.5
vi /etc/profile
增加:
export MAVEN_HOME=/usr/local/apache-maven-3.0.5

export PATH=$PATH:$MAVEN_HOME/bin
 
source /etc/profile 
mvn -v
2.2、对源码打包得到target/目录下的内容
 
mvn clean package 
 
将打包好的IK插件内容部署到ES中:
[zsz@VS-zsz ~]$ cd /home/zsz/elasticsearch-analysis-ik-1.10.0/target/releases/
[zsz@VS-zsz releases]$ mkdir /usr/local/elasticsearch-2.4.0/plugins/ik/
[zsz@VS-zsz releases]$ cp elasticsearch-analysis-ik-1.10.0.zip /usr/local/elasticsearch-2.4.0/plugins/ik/elasticsearch-analysis-ik-1.10.0.zip
[zsz@VS-zsz releases]$ unzip /usr/local/elasticsearch-2.4.0/plugins/ik/elasticsearch-analysis-ik-1.10.0.zip
[zsz@VS-zsz releases]$ cd /usr/local/elasticsearch-2.4.0/plugins/ik/
[zsz@VS-zsz ik]$ rm elasticsearch-analysis-ik-1.10.0.zip
[zsz@VS-zsz ik]$ mkdir /usr/local/elasticsearch-2.4.0/config/ik
 
将IK的配置copy到ElasticSearch的配置中:
[zsz@VS-zsz ik]$ cp /home/zsz/elasticsearch-analysis-ik-1.10.0/config /usr/local/elasticsearch-2.4.0/config/ik
 
更改ElasticSearch的配置:
[zsz@VS-zsz ik]$ vi /usr/local/elasticsearch-2.4.0/config/elasticsearch.yml
在最后加上分词解析器的配置:
index.analysis.analyzer.ik.type : "ik"
 
启动ElasticSearch:
[zsz@VS-zsz ik]$ cd  /usr/local/elasticsearch-2.4.0/
[zsz@VS-zsz elasticsearch-2.4.0]$ ./bin/elasticsearch -d
 
测试IK分词器的效果:
[zsz@VS-zsz elasticsearch-2.4.0]$ curl -XGET 'http://192.168.31.77:9200/_analyze?analyzer=ik' -d '岁月如梭'
{

    "tokens": [

        {

            "token": "岁月如梭",

            "start_offset": 0,

            "end_offset": 4,

            "type": "CN_WORD",

            "position": 0

        },

        {

            "token": "岁月",

            "start_offset": 0,

            "end_offset": 2,

            "type": "CN_WORD",

            "position": 1

        },

        {

            "token": "如梭",

            "start_offset": 2,

            "end_offset": 4,

            "type": "CN_WORD",

            "position": 2

        },

        {

            "token": "梭",

            "start_offset": 3,

            "end_offset": 4,

            "type": "CN_WORD",

            "position": 3

        }

    ]

}
[zsz@VS-zsz config]$ curl -XGET 'http://192.168.31.77:9200/_analyze?analyzer=ik' -d 'elasticsearch很受欢迎的的一款拥有活跃社区开源的搜索解决方案'
{

    "tokens": [

        {

            "token": "elasticsearch",

            "start_offset": 0,

            "end_offset": 13,

            "type": "CN_WORD",

            "position": 0

        },

        {

            "token": "elastic",

            "start_offset": 0,

            "end_offset": 7,

            "type": "CN_WORD",

            "position": 1

        },

        {

            "token": "很受",

            "start_offset": 13,

            "end_offset": 15,

            "type": "CN_WORD",

            "position": 2

        },

        {

            "token": "受欢迎",

            "start_offset": 14,

            "end_offset": 17,

            "type": "CN_WORD",

            "position": 3

        },

        {

            "token": "欢迎",

            "start_offset": 15,

            "end_offset": 17,

            "type": "CN_WORD",

            "position": 4

        },

        {

            "token": "一款",

            "start_offset": 19,

            "end_offset": 21,

            "type": "CN_WORD",

            "position": 5

        },

        {

            "token": "一",

            "start_offset": 19,

            "end_offset": 20,

            "type": "TYPE_CNUM",

            "position": 6

        },

        {

            "token": "款",

            "start_offset": 20,

            "end_offset": 21,

            "type": "COUNT",

            "position": 7

        },

        {

            "token": "拥有",

            "start_offset": 21,

            "end_offset": 23,

            "type": "CN_WORD",

            "position": 8

        },

        {

            "token": "拥",

            "start_offset": 21,

            "end_offset": 22,

            "type": "CN_WORD",

            "position": 9

        },

        {

            "token": "有",

            "start_offset": 22,

            "end_offset": 23,

            "type": "CN_CHAR",

            "position": 10

        },

        {

            "token": "活跃",

            "start_offset": 23,

            "end_offset": 25,

            "type": "CN_WORD",

            "position": 11

        },

        {

            "token": "跃",

            "start_offset": 24,

            "end_offset": 25,

            "type": "CN_WORD",

            "position": 12

        },

        {

            "token": "社区",

            "start_offset": 25,

            "end_offset": 27,

            "type": "CN_WORD",

            "position": 13

        },

        {

            "token": "开源",

            "start_offset": 27,

            "end_offset": 29,

            "type": "CN_WORD",

            "position": 14

        },

        {

            "token": "搜索",

            "start_offset": 30,

            "end_offset": 32,

            "type": "CN_WORD",

            "position": 15

        },

        {

            "token": "索解",

            "start_offset": 31,

            "end_offset": 33,

            "type": "CN_WORD",

            "position": 16

        },

        {

            "token": "索",

            "start_offset": 31,

            "end_offset": 32,

            "type": "CN_WORD",

            "position": 17

        },

        {

            "token": "解决方案",

            "start_offset": 32,

            "end_offset": 36,

            "type": "CN_WORD",

            "position": 18

        },

        {

            "token": "解决",

            "start_offset": 32,

            "end_offset": 34,

            "type": "CN_WORD",

            "position": 19

        },

        {

            "token": "方案",

            "start_offset": 34,

            "end_offset": 36,

            "type": "CN_WORD",

            "position": 20

        }

    ]

}
 
可以看到,中文分词变得更加合理。
 本文地址:http://www.cnblogs.com/zhongshengzhen/p/elasticsearch_ik.html