es - elasticsearch 自定义分析器 - 内建分词过滤器 - 12

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世界上并没有完美的程序,但是我们并不因此而沮丧,因为写程序就是一个不断追求完美的过程。

自定义分析器 :

  1. Character filters :
    1. 作用 : 字符的增、删、改转换
    2. 数量限制 : 可以有0个或多个
    3. 内建字符过滤器 :
    1. HTML Strip Character filter : 去除html标签
    2. Mapping Character filter : 映射替换
    3. Pattern Replace Character filter : 正则替换
  2. Tokenizer :
    1. 作用 :
    1. 分词
    2. 记录词的顺序和位置(短语查询)
    3. 记录词的开头和结尾位置(高亮)
    4. 记录词的类型(分类)
    2. 数量限制 : 有且只能有一个
    3. 分类 :
    1. 完整分词 :
    1. Standard
    2. Letter
    3. Lowercase
    4. whitespace
    5. UAX URL Email
    6. Classic
    7. Thai
    2. 切词 :
    1. N-Gram
    2. Edge N-Gram
    3. 文本 :
    1. Keyword
    2. Pattern
    3. Simple Pattern
    4. Char Group
    5. Simple Pattern split
    6. Path
  3. Token filters :
    1. 作用 : 分词的增、删、改转换
    2. 数量限制 : 可以有0个或多个
    3. 分类 :
    1. apostrophe
    2. asciifolding
    3. cjk bigram
    4. cjk width
    5. classic
    6. common grams
    7. conditional
    8. decimal digit
    9. delimited payload
    10. dictionary decompounder
    11. edge ngram
    12. elision
    13. fingerprint
    14. flatten_graph
    15. hunspell
    16. hyphenation decompounder
    17. keep types
    18. keep words
    19. keyword marker
    20. keyword repeat
    21. kstem
    22. length
    23. limit token count
    24. lowercase
    25. min_hash
    26. multiplexer
    27. ngram
    28. normalization
    29. pattern_capture
    30. pattern replace
    31. porter stem
    32. predicate script
    33. remove duplicates
    34. reverse
    35. shingle
    36. snowball
    37. stemmer
    38. stemmer override
    39. stop
    40. synonym
    41. synonym graph
    42. trim
    43. truncate
    44. unique
    45. uppercase
    46. word delimiter
    47. word delimiter graph

今天演示42-47

# trim token filter
# 作用 : 去除词前后的空格

GET /_analyze
{
  "tokenizer" : "keyword",
  "filter"    : ["trim"],
  "text"      : [" hello gooding me "]
}

# 结果

{
  "tokens" : [
    {
      "token" : "hello gooding me",
      "start_offset" : 0,
      "end_offset" : 18,
      "type" : "word",
      "position" : 0
    }
  ]
}
# truncate token filter
# 作用   : 将超出指定长度的词缩短到指定长度
# 配置项 : 
#   1. length : 指定长度,默认10

GET /_analyze
{
  "tokenizer" : "whitespace",
  "filter"    : [{
    "type"   : "truncate",
    "length" : 4
  }],
  "text" : ["hello gooding me"]
}

# 结果

{
  "tokens" : [
    {
      "token" : "hell",
      "start_offset" : 0,
      "end_offset" : 5,
      "type" : "word",
      "position" : 0
    },
    {
      "token" : "good",
      "start_offset" : 6,
      "end_offset" : 13,
      "type" : "word",
      "position" : 1
    },
    {
      "token" : "me",
      "start_offset" : 14,
      "end_offset" : 16,
      "type" : "word",
      "position" : 2
    }
  ]
}
# unique token filter
# 作用   : 去除重复的词
# 配置项 :
#   1. only_on_same_position : 知否只去除在同一位置重复的词,默认false

GET /_analyze
{
  "tokenizer" : "whitespace",
  "filter"    : ["unique"],
  "text"      : ["hello gooding gooding me me"]
}

# 结果

{
  "tokens" : [
    {
      "token" : "hello",
      "start_offset" : 0,
      "end_offset" : 5,
      "type" : "word",
      "position" : 0
    },
    {
      "token" : "gooding",
      "start_offset" : 6,
      "end_offset" : 13,
      "type" : "word",
      "position" : 1
    },
    {
      "token" : "me",
      "start_offset" : 22,
      "end_offset" : 24,
      "type" : "word",
      "position" : 2
    }
  ]
}
# uppercase token filter
# 作用 : 转大写

GET /_analyze
{
  "tokenizer" : "whitespace",
  "filter"    : ["uppercase"],
  "text"      : ["hello gooding me"]
}

# 结果
{
  "tokens" : [
    {
      "token" : "HELLO",
      "start_offset" : 0,
      "end_offset" : 5,
      "type" : "word",
      "position" : 0
    },
    {
      "token" : "GOODING",
      "start_offset" : 6,
      "end_offset" : 13,
      "type" : "word",
      "position" : 1
    },
    {
      "token" : "ME",
      "start_offset" : 14,
      "end_offset" : 16,
      "type" : "word",
      "position" : 2
    }
  ]
}
# word delimiter token filter
# 作用 : 
#   1. 以非字母数字分词
#   2. 以驼峰分词
#   3. 以字母数字分词
# 配置项 : 太多,不在2列举
# 备注   : 不推荐使用

GET /_analyze
{
  "tokenizer" : "keyword",
  "filter"    : ["word_delimiter"],
  "text"      : ["hello gooding me HelloGood Hello123 hello-good"]
}

# 结果

{
  "tokens" : [
    {
      "token" : "hello",
      "start_offset" : 0,
      "end_offset" : 5,
      "type" : "word",
      "position" : 0
    },
    {
      "token" : "gooding",
      "start_offset" : 6,
      "end_offset" : 13,
      "type" : "word",
      "position" : 1
    },
    {
      "token" : "me",
      "start_offset" : 14,
      "end_offset" : 16,
      "type" : "word",
      "position" : 2
    },
    {
      "token" : "Hello",
      "start_offset" : 17,
      "end_offset" : 22,
      "type" : "word",
      "position" : 3
    },
    {
      "token" : "Good",
      "start_offset" : 22,
      "end_offset" : 26,
      "type" : "word",
      "position" : 4
    },
    {
      "token" : "Hello",
      "start_offset" : 27,
      "end_offset" : 32,
      "type" : "word",
      "position" : 5
    },
    {
      "token" : "123",
      "start_offset" : 32,
      "end_offset" : 35,
      "type" : "word",
      "position" : 6
    },
    {
      "token" : "hello",
      "start_offset" : 36,
      "end_offset" : 41,
      "type" : "word",
      "position" : 7
    },
    {
      "token" : "good",
      "start_offset" : 42,
      "end_offset" : 46,
      "type" : "word",
      "position" : 8
    }
  ]
}
# word delimiter token filter
# 作用   : 与word delimiter一致
# 配置项 : 太多,不予介绍
# 备注   : 推荐用在keyword分词器上

GET /_analyze
{
  "tokenizer" : "keyword",
  "filter"    : ["word_delimiter_graph"],
  "text"      : ["hello gooding me HelloGood Hello123 hello-good"]
}

# 结果

{
  "tokens" : [
    {
      "token" : "hello",
      "start_offset" : 0,
      "end_offset" : 5,
      "type" : "word",
      "position" : 0
    },
    {
      "token" : "gooding",
      "start_offset" : 6,
      "end_offset" : 13,
      "type" : "word",
      "position" : 1
    },
    {
      "token" : "me",
      "start_offset" : 14,
      "end_offset" : 16,
      "type" : "word",
      "position" : 2
    },
    {
      "token" : "Hello",
      "start_offset" : 17,
      "end_offset" : 22,
      "type" : "word",
      "position" : 3
    },
    {
      "token" : "Good",
      "start_offset" : 22,
      "end_offset" : 26,
      "type" : "word",
      "position" : 4
    },
    {
      "token" : "Hello",
      "start_offset" : 27,
      "end_offset" : 32,
      "type" : "word",
      "position" : 5
    },
    {
      "token" : "123",
      "start_offset" : 32,
      "end_offset" : 35,
      "type" : "word",
      "position" : 6
    },
    {
      "token" : "hello",
      "start_offset" : 36,
      "end_offset" : 41,
      "type" : "word",
      "position" : 7
    },
    {
      "token" : "good",
      "start_offset" : 42,
      "end_offset" : 46,
      "type" : "word",
      "position" : 8
    }
  ]
}