使用edge_ngram过滤器时如何突出显示部分单词

Question

我在我的分析器中使用了edge_ngram过滤器，例如我索引了一个单词"EVA京"，它将被映射到一个数组E，EV，EVA，京。然后我搜索"EV"，原因是"EVA京“可以被召回。但是高亮显示是错误的！高亮显示的结果是"EVA京"，而不是"EVA京“。

有人能给我一个提示如何纠正高亮结果吗？

我的索引设置和映射：

PUT my-index-001
{
  "settings": {
    "analysis": {
      "filter": {
        "edge_ngram_1_100": {
          "type": "edge_ngram",
          "min_gram": 1,
          "max_gram": 100
        }
      },
      
      "analyzer": {
        "my_analyzer": {
          "type": "custom",
          "tokenizer": "standard",
          "filter": ["lowercase", "edge_ngram_1_100"]
        }
      }
    }
  }, 
  "mappings": {
    "properties": {
      "name": {
        "type": "text",
        "analyzer": "my_analyzer",
        "search_analyzer": "standard"
      }
    }
  }
}

然后添加一句话：

PUT my-index-001/_doc/1
{
  "name": "EVA新世纪福音战士"
}

然后我会搜索：

GET my-index-001/_search
{
  "query": {
    "match": {
      "name": {
        "query": "EV"
        , "operator": "and"
      }
    }
  }
  , "highlight": {
    "fields": {
      "name": {
      }
    }
  }
}

搜索结果为：

{
  "took" : 3,
  "timed_out" : false,
  "_shards" : {
    "total" : 1,
    "successful" : 1,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : {
      "value" : 1,
      "relation" : "eq"
    },
    "max_score" : 0.3133171,
    "hits" : [
      {
        "_index" : "my-index-001",
        "_type" : "_doc",
        "_id" : "1",
        "_score" : 0.3133171,
        "_source" : {
          "name" : "EVA新世纪福音战士"
        },
        "highlight" : {
          "name" : [
            "<em>EVA</em>新世纪福音战士"
          ]
        }
      }
    ]
  }
}

Answer 1

如果您需要对文档的部分单词匹配结果进行highlight，则可以通过以下方式来实现：

添加一个包含索引数据、映射、搜索查询和搜索结果的工作示例

索引映射：

{
  "settings": {
    "analysis": {
      "analyzer": {
        "my_analyzer": {
          "tokenizer": "my_tokenizer"
        }
      },
      "tokenizer": {
        "my_tokenizer": {
          "type": "edge_ngram",
          "min_gram": 1,
          "max_gram": 20,
          "token_chars": [
            "letter",
            "digit"
          ]
        }
      }
    },
    "max_ngram_diff": 50
  },
  "mappings": {
    "properties": {
      "name": {
        "type": "text",
        "analyzer": "my_analyzer"
      }
    }
  }
}

索引数据：

{
    "name":"EVA新世纪福音战士"
}

搜索查询：

{
  "query": {
    "match": {
      "name": {
        "query": "EV"
      }
    }
  },
  "highlight": {
    "fields": {
      "*": {
        "type": "plain",
        "fragment_size": 20,
        "pre_tags": "<span class='bold'>",
        "post_tags": "</span>",
        "number_of_fragments": 1
      }
    }
  }
}

搜索结果：

"hits": [
  {
    "_index": "65821975",
    "_type": "_doc",
    "_id": "1",
    "_score": 0.5753642,
    "_source": {
      "name": "EVA新世纪福音战士"
    },
    "highlight": {
      "name": [
        "<span class='bold'>EV</span>A新世纪福音战士"
      ]
    }
  }
]