elasticsearch文档-analysis

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analysis基本概念===全文搜索引擎会用某种算法对要建索引的文档进行分析, 从文档中提取出若干Token(词元), 这些算法称为Tokenizer(分词器), 这些Token会被进一步处理, 比如转成小写等, 这些处理算法被称为Token Filter(词元处理器), 被处理后的结果被称为Term(词), 文档中包含了几个这样的Term被称为Frequency(词频)。 引擎会建立Term和原文档的Inverted Index(倒排索引), 这样就能根据Term很快到找到源文档了。    文本被Tokenizer处理前可能要做一些预处理, 比如去掉里面的HTML标记, 这些处理的算法被称为Character Filter(字符过滤器), 这整个的分析算法被称为Analyzer(分析器)。 ES内置了很多Analyzer, 还有很多第三方的Analyzer插件, 比如一些处理中文的Analyzer(中文分词)。 analyzer、 tokenizer、 filter可以在elasticsearch.yml 配置, 下面是配置例子```index :    analysis :        analyzer :            standard :                type : standard                stopwords : [stop1, stop2]            myAnalyzer1 :                type : standard                stopwords : [stop1, stop2, stop3]                max_token_length : 500            # configure a custom analyzer which is            # exactly like the default standard analyzer            myAnalyzer2 :                tokenizer : standard                filter : [standard, lowercase, stop]        tokenizer :            myTokenizer1 :                type : standard                max_token_length : 900            myTokenizer2 :                type : keyword                buffer_size : 512        filter :            myTokenFilter1 :                type : stop                stopwords : [stop1, stop2, stop3, stop4]            myTokenFilter2 :                type : length                min : 0                max : 2000```analyzer===ES内置若干analyzer, 另外还可以用内置的character filter, tokenizer, token filter组装一个analyzer(custom analyzer), 比如```index :    analysis :        analyzer :            myAnalyzer :                tokenizer : standard                filter : [standard, lowercase, stop]```如果你要使用第三方的analyzer插件,需要先在配置文件elasticsearch.yml中注册, 下面是配置IkAnalyzer的例子```index:  analysis:    analyzer:            ik:          alias: [ik_analyzer]          type: org.elasticsearch.index.analysis.IkAnalyzerProvider```当一个analyzer在配置文件中被注册到一个名字(logical name)下后,在mapping定义或者一些API里就可以用这个名字来引用该analyzer了,比如```"message": {    "type": "string",    "indexAnalyzer": "ik",    "searchAnalyzer": "ik"}```如果没有指定索引和搜索用的analyzer,ES会用默认的analyzer来处理,也就是名字(logical name)为`default`, `default_index`, `default_search`的analyzer。 从名字可以看出来,`default`是索引和搜索时用的默认的analyzer,`default_index`是索引时用的默认的analyzer, `default_search`是查询时用的默认analyzer。下面是在elasticsearch.yml中配置默认analyzer的例子```index:  analysis:    analyzer:        default_index:            tokenizer: standard            filter: [standard, lowercase, my_synonym, my_snow]        default_search:            tokenizer: standard            filter: [standard, lowercase, stop]```或者用这种格式```index.analysis.analyzer.default.type : "mmseg"```一个analyzer可以起若干别名,比如在下面的例子中,standard analyzer可以用alias1或者alias2来引用```index :  analysis :    analyzer。 :      standard :        alias: [alias1, alias2]        type : standard        stopwords : [test1, test2, test3]```下面是内置的一些analyzer。| analyzer              | logical name  | description                               || ----------------------|:-------------:| :-----------------------------------------|| standard analyzer     | standard      | standard tokenizer, standard filter, lower case filter, stop filter || simple analyzer       | simple        | lower case tokenizer                      || stop analyzer         | stop          | lower case tokenizer, stop filter         || keyword analyzer      | keyword       | 不分词,内容整体作为一个token(not_analyzed) || pattern analyzer      | whitespace    | 正则表达式分词,默认匹配\W+                 || language analyzers    | [lang](http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/analysis-lang-analyzer.html)  | 各种语言 || snowball analyzer     | snowball      | standard tokenizer, standard filter, lower case filter, stop filter, snowball filter || custom analyzer       | custom        | 一个Tokenizer, 零个或多个Token Filter, 零个或多个Char Filter |tokenizer===ES内置的tokenizer列表。| tokenizer             | logical name  | description                           || ----------------------|:-------------:| :-------------------------------------|| standard tokenizer    | standard      |                                       || edge ngram tokenizer  | edgeNGram     |                                       || keyword tokenizer     | keyword       | 不分词                                 || letter analyzer       | letter        | 按单词分                               || lowercase analyzer    | lowercase     | letter tokenizer, lower case filter   || ngram analyzers       | nGram         |                                       || whitespace analyzer   | whitespace    | 以空格为分隔符拆分                      || pattern analyzer      | pattern       | 定义分隔符的正则表达式                  || uax email url analyzer| uax_url_email | 不拆分url和email                       || path hierarchy analyzer| path_hierarchy| 处理类似`/path/to/somthing`样式的字符串|token filter===ES内置的token filter列表。| token filter          | logical name  | description                           || ----------------------|:-------------:| :-------------------------------------|| standard filter       | standard      |                                       || ascii folding filter  | asciifolding  |                                       || length filter         | length        | 去掉太长或者太短的                      || lowercase filter      | lowercase     | 转成小写                               || ngram filter          | nGram         |                                       || edge ngram filter     | edgeNGram     |                                       || porter stem filter    | porterStem    | 波特词干算法                            || shingle filter        | shingle       | 定义分隔符的正则表达式                  || stop filter           | stop          | 移除 stop words                        || word delimiter filter | word_delimiter| 将一个单词再拆成子分词                   || stemmer token filter  | stemmer       |                                        || stemmer override filter| stemmer_override|                                     || keyword marker filter | keyword_marker|                                        || keyword repeat filter | keyword_repeat|                                        || kstem filter          | kstem         |                                        || snowball filter       | snowball      |                                        || phonetic filter       | phonetic      | [插件](https://github.com/elasticsearch/elasticsearch-analysis-phonetic) || synonym filter        | synonyms      | 处理同义词                              || compound word filter  | dictionary_decompounder, hyphenation_decompounder | 分解复合词  || reverse filter        | reverse       | 反转字符串                              || elision filter        | elision       | 去掉缩略语                              || truncate filter       | truncate      | 截断字符串                              || unique filter         | unique        |                                        || pattern capture filter| pattern_capture|                                       || pattern replace filte | pattern_replace| 用正则表达式替换                        || trim filter           | trim          | 去掉空格                                || limit token count filter| limit       | 限制token数量                           || hunspell filter       | hunspell      | 拼写检查                                || common grams filter   | common_grams  |                                        || normalization filter  | arabic_normalization, persian_normalization |          |character filter===ES内置的character filter列表| character filter          | logical name  | description               || --------------------------|:-------------:| :-------------------------|| mapping char filter       | mapping       | 根据配置的映射关系替换字符   || html strip char filter    | html_strip    | 去掉HTML元素               || pattern replace char filter| pattern_replace| 用正则表达式处理字符串    |icu plugin===[icu analysis 插件](https://github.com/elasticsearch/elasticsearch-analysis-icu)http://www.csdn123.com/html/itweb/20131030/195710.htm
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