ElasticSeach Completion-Suggester在搜索文档时删除最后一个字符

Question

我正在设置基于ElasticSearch的自动完成功能。我已经建立了自动完成功能，但是它有一个错误，它会从搜索字符串中删除最后一个字符。

例如如果我搜索“ CBL”，那么它将搜索“ CB”并返回以下结果。

C.B.BUILDERS AND CONSTRUCTIONS Private Limited
CB BUSINESS SOLUTION PRIVATE LIMITED
C.B.CHAINS LIMITED
C.B. CHEMICALS LTD
C B COMPUSYSTEMS PRIVATE LIMITED

根据功能，它应该返回低于结果的位置。

 CBL DATA RECOVERY TECHNOLOGIES PRIVATE LIMITED
 CBL DATA SCIENCE PRIVATE LIMITED
 CBL GLOBAL INDUSTRIES PRIVATE LIMITED
 CBL INVESTMENTS LTD
 CBL Trading Concepts Private Limited

这是我应用的索引设置和配置。

{
  "settings": {
    "index": {
      "analysis": {
        "filter": {},
        "analyzer": {
          "keyword_analyzer": {
            "filter": [
              "lowercase",
              "asciifolding",
              "trim"
            ],
            "char_filter": [],
            "type": "custom",
            "tokenizer": "keyword"
          },
          "edge_ngram_analyzer": {
            "filter": [
              "lowercase"
            ],
            "tokenizer": "edge_ngram_tokenizer"
          },
          "edge_ngram_search_analyzer": {
            "tokenizer": "lowercase"
          }
        },
        "tokenizer": {
          "edge_ngram_tokenizer": {
            "type": "edge_ngram",
            "min_gram": 2,
            "max_gram": 5,
            "token_chars": [
              "letter"
            ]
          }
        }
      }
    }
  },
  "mappings": {
    "_doc": {
      "properties": {
        "CleanedCompanyName": {
          "type": "text",
          "fields": {
            "keywordstring": {
              "type": "text",
              "analyzer": "keyword_analyzer"
            },
            "edgengram": {
              "type": "text",
              "analyzer": "edge_ngram_analyzer",
              "search_analyzer": "edge_ngram_search_analyzer"
            },
            "completion": {
              "type": "completion"
            }
          },
          "analyzer": "standard"
        }
      }
    }
  }
}

下面是我正在使用的搜索查询。

{ "suggest": 
    { "companyname-suggest-fuzzy": 
        { "prefix": "CBL", 
          "completion": { 
                "field": "CleanedCompanyName.completion", 
                "fuzzy": { 
                    "fuzziness": "AUTO" 
                    } 
                } 
        } 
    } 
}