ElasticSearch使用拼音分词器实现中文按拼音首字母排序

前提：某个字段是中文，要用这个字段做升序，结果es默认的是unicode编码排序，与需求按拼音排序不符，故而引入了拼音分词器实现
1、下载拼音分词器插件
bin/elasticsearch-plugin install https://github.com/medcl/elasticsearch-analysis-pinyin/releases/download/v7.17.3/elasticsearch-analysis-pinyin-7.17.3.zip
2、创建索引添加sort内容
put new_index/ { "settings": { "analysis": { "analyzer": { "pinyin_analyzer": { "tokenizer": "pinyin_tokenizer" } }, "tokenizer": { "pinyin_tokenizer": { "type": "pinyin", "keep_first_letter": "true", "keep_none_chinese_in_first_letter": "true", "keep_separate_first_letter": "false", "keep_full_pinyin": "false", "keep_joined_full_pinyin": "false", "keep_none_chinese": "false", "keep_none_chinese_together": "false", "keep_none_chinese_in_joined_full_pinyin": "false", "none_chinese_pinyin_tokenize": "false", "keep_original": "false", "lowercase": "false", "trim_whitespace": "false", "remove_duplicated_term": "false" } } } }, "mappings" : { "properties" : { "name" : { "type" : "keyword", "fields": { "pinyin": { "type": "text", "analyzer": "pinyin_analyzer", "search_analyzer": "standard", "fielddata": true } } } } } }
3、查询方式
POST test/_search { "sort": [ { "name.pinyin": { "order": "asc" } } ] }

主要问题：
1、tokenizer的各种设置会导致分词的结果是一个list,sort里面的mode的默认值是min会导致按分词结果升序再按更新时间降序的结果不准确，故只设置 "keep_first_letter": "true", "keep_none_chinese_in_first_letter": "true"即只会有按拼音和非中文的字符展示的首字母分词结果

2、在已有的index上调整字段按分词结果排序，需要新增一个index设置name字段分词，然后把已存在的index数据转移到新增的index,然后删除原来的索引，再新增原来索引同名索引并以新索引为别名
put new_index/ { "settings": { "analysis": { "analyzer": { "pinyin_analyzer": { "tokenizer": "pinyin_tokenizer" } }, "tokenizer": { "pinyin_tokenizer": { "type": "pinyin", "keep_first_letter": "true", "keep_none_chinese_in_first_letter": "true", "keep_separate_first_letter": "false", "keep_full_pinyin": "false", "keep_joined_full_pinyin": "false", "keep_none_chinese": "false", "keep_none_chinese_together": "false", "keep_none_chinese_in_joined_full_pinyin": "false", "none_chinese_pinyin_tokenize": "false", "keep_original": "false", "lowercase": "false", "trim_whitespace": "false", "remove_duplicated_term": "false" } } } }, "mappings" : { "properties" : { "name" : { "type" : "keyword", "fields": { "pinyin": { "type": "text", "analyzer": "pinyin_analyzer", "search_analyzer": "standard", "fielddata": true } } } } } }

POST /_reindex { "source": { "index": "old_index" }, "dest": { "index": "new_index" } }

DELETE old_index

POST /_aliases { "actions": [ { "add": { "index": "old_index", "alias": "new_index" } } ] }
附拼音分词属性简介

属性	说明
keep_first_letter	启用此选项时，例如：刘德华> ldh，默认值：true
keep_separate_first_letter	启用该选项时，将保留第一个字母分开，例如：刘德华> l，d，h，默认：false，注意：查询结果也许是太模糊，由于长期过频
limit_first_letter_length	设置first_letter结果的最大长度，默认值：16
keep_full_pinyin	当启用该选项，例如：刘德华> [ liu，de，hua]，默认值：true
keep_joined_full_pinyin	当启用此选项时，例如：刘德华> [ liudehua]，默认值：false
keep_none_chinese	在结果中保留非中文字母或数字，默认值：true
keep_none_chinese_together	保持非中国信一起，默认值：true，如：DJ音乐家- > DJ，yin，yue，jia，当设置为false，例如：DJ音乐家- > D，J，yin，yue，jia，注意：keep_none_chinese必须先启动
keep_none_chinese_in_first_letter	第一个字母保持非中文字母，例如：刘德华AT2016- > ldhat2016，默认值：true
keep_none_chinese_in_joined_full_pinyin	保留非中文字母加入完整拼音，例如：刘德华2016- > liudehua2016，默认：false
none_chinese_pinyin_tokenize	打破非中国信成单独的拼音项，如果他们拼音，默认值：true，如：liudehuaalibaba13zhuanghan- > liu，de，hua，a，li，ba，ba，13，zhuang，han，注意：keep_none_chinese和keep_none_chinese_together应首先启用
keep_original	当启用此选项时，也会保留原始输入，默认值：false
lowercase	小写非中文字母，默认值：true
trim_whitespace	默认值：true
remove_duplicated_term	当启用此选项时，将删除重复项以保存索引，例如：de的> de，默认值：false，注意：位置相关查询可能受影响

参考链接：https://blog.csdn.net/qq_41444892/article/details/129685138
https://blog.csdn.net/jifgnie/article/details/130938996
https://blog.csdn.net/qq_31286957/article/details/130842632