Elasticsearch查询

Question

I need some help to query a field in my index. This field will have data such as:

GB10
GB40
GB45
UK09
UK40

If I have the query:

"Show me the code GB 40"

( note the space between GB and 40 )

I would like the JSON to return the result for the GB40 as the top result. Can anyone help with how I can I go about doing this and any changes I might need to make? I haven't set the field as analysed yet.

Answer 1

Ok, if you have words with such pattern then you might want to exploit split on letter-number transitions: "SD500" → "SD", "500" using word_delimiter tokenizer filter in elastic.

You can split the word on letter-word transition using this filter to have both letter and number part of the word stored seperately on inverted index. Neverthless this will also keep a copy of exact value on index.

Please refer the mappings and queries below

PUT testindex_48
{
    "settings": {
        "analysis": {
            "analyzer": {

                "word_delimiter_analyzer": {
                    "tokenizer": "whitespace",
                    "filter": [
                        "lowercase",
                        "word_delimiter"
                    ],
                    "ignore_case": true,
                    "preserve_original": true
                }
            },
             "filter":{

            "word_delimiter":{
              "type":"word_delimiter",
              "generate_word_parts":true,
              "preserve_original": true
            }
        }
        }
    },
    "mappings": {
        "table1": {
            "properties": {
                "title": {
                    "type": "string",
                    "analyzer": "word_delimiter_analyzer"
                }
            }
        }
    }
}

POST testindex_48/table1
{
  "title" : "EC450"
}

POST testindex_48/table1/_search
{
  "query": {"bool": {"must": [
    {"term": {
      "title": {
        "value": "450"
      }
    }}
  ]}}
}

POST testindex_48/table1/_search
{
  "query": {"bool": {"must": [
    {"term": {
      "title": {
        "value": "ec"
      }
    }}
  ]}}
}


POST testindex_48/table1/_search
{
  "query": {"bool": {"must": [
    {"term": {
      "title": {
        "value": "ec450"
      }
    }}
  ]}}
}

Now your usecase if user enters "EC 450", you can build a similar query like the follows.