I'm trying to create an autocomplete with edge n-gram but when I search for a string with numbers the search doesn't return anything.

For example, I want to search for 10k and I have several items with 10kab. If I search for "10kab" or "kab" it works fine, but if I only search for "10k" it doesn't return anything. If it doesn't have numbers it works fine. For example, searching for "som" I get results for "something".

This is the index settings I have:

{
    "settings": {
        "analysis": {
            "analyzer": {
                "autocomplete": {
                    "tokenizer": "autocomplete",
                    "filter": [
                        "lowercase"
                    ]
                },
                "autocomplete_search": {
                    "tokenizer": "lowercase"
                }
            },
            "tokenizer": {
                "autocomplete": {
                    "type": "edge_ngram",
                    "min_gram": 2,
                    "max_gram": 10,
                    "token_chars": [
                        "letter"
                    ]
                }
            }
        }
    },
    "mappings": {
        "properties": {
            "search": {
                    "type": "text",
                    "fields": {
                            "keyword": {
                                    "type": "keyword",
                                    "ignore_above": 256
                            }
                    },
                    "analyzer": "autocomplete",
                    "search_analyzer": "autocomplete_search"
            }
        }
    }
}

I even tried to add digit to the token_chars but it seems to work worst as not even "10kab" works.

CodePudding user response：

Your autocomplete tokenizer is configured to only include letter, you should add digit as well

            "autocomplete": {
                "type": "edge_ngram",
                "min_gram": 2,
                "max_gram": 10,
                "token_chars": [
                    "letter",
                    "digit"              <--- add this
                ]
            }

Also note that your search_analyzer is based on the lowercase tokenizer which gets rid of digits, so searching for 10k will actually search just for k and that won't match anything.

You should change your autocomplete_search analyzer to the following and then your searches will start working:

    "autocomplete_search": {
      "tokenizer": "keyword",
      "filter": [
        "lowercase"
      ]
    }