部分词搜索 - ElasticSearch 1.7.2

Question

我一直在尝试使用 ElasticSearch 为应用程序构建搜索模块。下面是我从其他 StackOverflow 帖子中阅读的示例代码构建的索引结构。

{
  "megacorp4":{
    "settings":{
      "analysis":{
        "analyzer":{
          "my_analyzer":{
            "type":"custom",
            "tokenizer":"my_ngram_tokenizer",
            "filter":[
              "my_ngram_filter"
            ]
          }
        },
        "filter":{
          "my_ngram_filter":{
            "type":"edgeNGram",
            "min_gram":3,
            "max_gram":15
          }
        },
        "tokenizer":{
          "my_ngram_tokenizer":{
            "type":"edgeNGram",
            "min_gram":3,
            "max_gram":15
          }
        }
      },
      "mappings":{
        "employee":{
          "properties":{
            "about":{
              "type":"string",
              "analyzer":"my_analyzer"
            },
            "age":{
              "type":"long"
            },
            "first_name":{
              "type":"string"
            },
            "interests":{
              "type":"string",
              "analyzer":"my_analyzer"
            },
            "last_name":{
              "type":"string"
            }
          }
        }
      }
    }
  }
}

以下是我插入的用于测试搜索功能的记录

[
  {
    "first_name":"John",
    "last_name":"Smith",
    "age":25,
    "about":"I love to go rock climbing",
    "interests":[
      "sports",
      "music"
    ]
  },
  {
    "first_name":"Douglas",
    "last_name":"Fir",
    "age":35,
    "about":"I like to build album climb cabinets",
    "interests":[
      "forestry",
      "music"
    ]
  },
  {
    "first_name":"Jane",
    "last_name":"Smith",
    "age":32,
    "about":"I like to collect rock albums",
    "interests":[
      "music"
    ]
  }
]

我使用 API（通过 POSTMAN）和 Python 客户端对“关于”列进行了搜索，如下所示：

API 查询：

localhost:9200/megacorp4/_search?q=climb

Python 查询：

from elasticsearch import Elasticsearch
from pprint import pprint
es = Elasticsearch()
res = es.search(index="megacorp4", body={"query": {"match": {'about':"climb"}}})
pprint(res)

我只能获得完全匹配，并且在输出中没有得到带有“爬升”的结果。但是，当我在查询中将 'climb' 替换为 'climb*' 时，我得到 2 条记录为 'climb' 和 'climbing'。我不想使用 '*' 通配符方法。

我也尝试过使用“english”、“standard”和“ngram”内置分析器，但似乎没有任何效果。

需要帮助来实现在全文中将关键字搜索为部分单词。

提前致谢。

Answer 1

改用这个映射：

删除测试

PUT /test
{
  "settings": {
    "analysis": {
      "analyzer": {
        "my_analyzer": {
          "type": "custom",
          "tokenizer": "standard",
          "filter": [
            "my_ngram_filter"
          ]
        }
      },
      "filter": {
        "my_ngram_filter": {
          "type": "edgeNGram",
          "min_gram": 3,
          "max_gram": 15
        }
      }
    }
  },
  "mappings": {
    "employee": {
      "properties": {
        "about": {
          "type": "string",
          "analyzer": "my_analyzer"
        },
        "age": {
          "type": "long"
        },
        "first_name": {
          "type": "string"
        },
        "interests": {
          "type": "string",
          "analyzer": "my_analyzer"
        },
        "last_name": {
          "type": "string"
        }
      }
    }
  }
}

POST /test/employee/_bulk
{"index":{}}
{"first_name":"John","last_name":"Smith","age":25,"about":"I love to go rock climbing","interests":["sports","music"]}
{"index":{}}
{"first_name":"Douglas","last_name":"Fir","age":35,"about":"I like to build album climb cabinets","interests":["forestry","music"]}
{"index":{}}
{"first_name":"Jane","last_name":"Smith","age":32,"about":"I like to collect rock albums","interests":["music"]}

GET /test/_search?q=about:climb

GET /test/_search
{
  "query": {
    "query_string": {
      "query": "about:climb"
    }
  }
}

GET /test/_search
{
  "query": {
    "match": {
      "about": "climb"
    }
  }
}

两个变化：

• settings 部分需要另一个右大括号
• 用另一个替换您的自定义分词器（这对您没有帮助，因为您已经拥有 edgeNGram 过滤器），我的建议是standard分词器

对于?q=climb 部分，默认情况下会搜索_all 字段，该字段使用standard 分析器而不是您的自定义分析器进行分析。

所以，正确的查询是localhost:9200/megacorp4/_search?q=about:climb。