ElasticSearch 自定义相似度插件 - 根据命中数排序

2023-04-13
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自定义相似度算法(只考虑词频/命中数)

在使用 Elasticsearch 的时候，针对排序结果，有些时候只关注对应的词出现的次数，相当于只考虑词频，这个时候就可以使用当前的插件。当前插件继承了 TFIDFSimilarity 类， TfSimilarity 只考虑了词频，并将其注册到插件中。实现结果如下，前两个代码段落分别是 mapping setting 配置文件，第三个代码段是请求，第四个代码段是结果。详细查看第四个代码段落的 _score 得分，发现 _score 的值等于请求参数'效果'在文本中出现的次数，至此证明当前插件有效。

"studentIntro": {    "type": "text",    "analyzer": "ik_max_word",    "search_analyzer": "ik_smart",    "similarity": "tf_similarity"},

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{    "similarity": {        "tf_similarity": {            "type": "tf_similarity"        }    }}

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{    "size": 100,    "query": {        "bool": {            "should": [                {                    "match": {                        "studentIntro": {                            "query": "效果"                        }                    }                }            ]        }    }}

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{    "took": 2,    "timed_out": false,    "_shards": {        "total": 1,        "successful": 1,        "skipped": 0,        "failed": 0    },    "hits": {        "total": {            "value": 6,            "relation": "eq"        },        "max_score": 2.0,        "hits": [            {                "_index": "student",                "_type": "_doc",                "_id": "26",                "_score": 2.0,                "_source": {                    "_class": "com.pap.es.domain.Student",                    "id": "26",                    "studentName": "洋柿子",                    "studentNo": "GAO202209",                    "studentAge": 11,                    "studentBirth": "2023-04-13 03:45:02",                    "studentIntro": "我是效果，我要看看分词的效果",                    "studentTags": "D",                    "gradePoint": 2.35                }            },            {                "_index": "student",                "_type": "_doc",                "_id": "4",                "_score": 1.0,                "_source": {                    "_class": "com.pap.es.domain.Student",                    "id": "4",                    "studentName": "洋柿子",                    "studentNo": "GAO202209",                    "studentAge": 11,                    "studentBirth": "2023-04-13 03:44:58",                    "studentIntro": "我是洋柿子，我要看看分词的效果",                    "studentTags": "D",                    "gradePoint": 2.35                }            },            {                "_index": "student",                "_type": "_doc",                "_id": "3",                "_score": 1.0,                "_source": {                    "_class": "com.pap.es.domain.Student",                    "id": "3",                    "studentName": "圣女果",                    "studentNo": "123GAO56",                    "studentAge": 13,                    "studentBirth": "2023-04-13 03:44:58",                    "studentIntro": "我是圣女果，我要看看分词的效果",                    "studentTags": "C",                    "gradePoint": 2.25                }            },            {                "_index": "student",                "_type": "_doc",                "_id": "1",                "_score": 1.0,                "_source": {                    "_class": "com.pap.es.domain.Student",                    "id": "1",                    "studentName": "西红柿",                    "studentNo": "YI123GAO",                    "studentAge": 12,                    "studentBirth": "2023-04-13 03:44:57",                    "studentIntro": "我是西红柿，我要看看分词的效果",                    "studentTags": "A",                    "gradePoint": 2.23                }            },            {                "_index": "student",                "_type": "_doc",                "_id": "2",                "_score": 1.0,                "_source": {                    "_class": "com.pap.es.domain.Student",                    "id": "2",                    "studentName": "番茄",                    "studentNo": "GAO456YH",                    "studentAge": 12,                    "studentBirth": "2023-04-13 03:44:58",                    "studentIntro": "我是番茄，我要看看分词的效果",                    "studentTags": "B",                    "gradePoint": 2.33                }            },            {                "_index": "student",                "_type": "_doc",                "_id": "6",                "_score": 1.0,                "_source": {                    "_class": "com.pap.es.domain.Student",                    "id": "6",                    "studentName": "效果",                    "studentNo": "20191202",                    "studentAge": 14,                    "studentBirth": "2023-04-13 03:44:59",                    "studentIntro": "效果",                    "studentTags": "A,B,C",                    "gradePoint": 2.13                }            }        ]    }}

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使用方法

clone 当前代码，修改 pom.xml 文件中对应的 elasticsearch 版本；
mvn clean package 打包；
防止到 elasticsearch 目录的 plugins 文件夹下，并重启 ES；

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ElasticSearch 自定义相似度插件 - 根据命中数排序

自定义相似度算法(只考虑词频/命中数)

使用方法

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