29深度探秘搜索技术_实战掌握误拼写时的fuzzy模糊搜索技术

搜索的时候，可能输入的搜索文本会出现误拼写的情况

doc1: hello world doc2: hello java

搜索：hallo world

fuzzy搜索技术 --> 自动将拼写错误的搜索文本，进行纠正，纠正以后去尝试匹配索引中的数据

新增text字段

POST /my_index/my_type/_bulk
{ "index": { "_id": 1 }}
{ "text": "Surprise me!"}
{ "index": { "_id": 2 }}
{ "text": "That was surprising."}
{ "index": { "_id": 3 }}
{ "text": "I wasn't surprised."}

使用fuzzy搜索

GET /my_index/my_type/_search 
{
  "query": {
    "fuzzy": {
      "text": {
        "value": "surprize",
        "fuzziness": 2
      }
    }
  }
}

响应结果

{
  "took": 20,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "skipped": 0,
    "failed": 0
  },
  "hits": {
    "total": 2,
    "max_score": 0.22585157,
    "hits": [
      {
        "_index": "my_index",
        "_type": "my_type",
        "_id": "1",
        "_score": 0.22585157,
        "_source": {
          "text": "Surprise me!"
        }
      },
      {
        "_index": "my_index",
        "_type": "my_type",
        "_id": "3",
        "_score": 0.1898702,
        "_source": {
          "text": "I wasn't surprised."
        }
      }
    ]
  }
}

surprize --> 拼写错误 打成 surprise --> s -> z

surprize --> surprise -> z -> s，纠正一个字母，就可以匹配上，所以在fuziness指定的2范围内 surprize --> surprised -> z -> s，末尾加个d，纠正了2次，也可以匹配上，在fuziness指定的2范围内 surprize --> surprising -> z -> s，去掉e，加i n g3次，总共要5次，才可以匹配上，在fuziness指定的2范围内纠正不了

fuzzy搜索以后，会自动尝试将你的搜索文本进行纠错，然后去跟文本进行匹配 fuzziness，你的搜索文本最多可以纠正几个字母去跟你的数据进行匹配，默认如果不设置，就是2

GET /my_index/my_type/_search 
{
  "query": {
    "match": {
      "text": {
        "query": "SURPIZE ME",
        "fuzziness": "AUTO",
        "operator": "and"
      }
    }
  }
}

响应结果

{
  "took": 3,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "skipped": 0,
    "failed": 0
  },
  "hits": {
    "total": 1,
    "max_score": 0.44248468,
    "hits": [
      {
        "_index": "my_index",
        "_type": "my_type",
        "_id": "1",
        "_score": 0.44248468,
        "_source": {
          "text": "Surprise me!"
        }
      }
    ]
  }
}