find substring with special chars in Elastic Search

Question

I'm new to elastic search. I want to search by substring, that consists of numbers and symbols like "/" and "-". For example, I create an index with default settings and one indexed field:

curl -XPUT "http://localhost:9200/test/" -d ' {
    "mappings" : {
            "properties": {
                    "test_field": {
                            "type": "string"
                    }
            }
    }
} '

Then, I add some data into my index:

curl -XPOST "http://localhost:9200/test/test_field" -d '{ "test_field" : "14/21-35" }'
curl -XPOST "http://localhost:9200/test/test_field" -d '{ "test_field" : "1/1-35" }'
curl -XPOST "http://localhost:9200/test/test_field" -d '{ "test_field" : "1/2-25" }'

After refreshing an index I perform searching. So, i want to find data, in which "test_field" begins with "1/1". My request:

curl -X GET "http://localhost:9200/test/_search?pretty=true" -d '{"query":{"query_string":{"query":"1/1*"}}}'

returns no hits. If i remove the star symbol, then in response i see two hits: "1/1-35" and "1/2-25". If i try to escape slash symbol by backslash ("1\/1*"), results are the same respectively.

When there is "-" symbol in my query, then i must escape this Lucene special character. So i send next search request:

curl -X GET "http://localhost:9200/test/_search?pretty=true" -d '{"query":{"query_string":{"query":"*1\-3*"}}}'

and it returns with parsing error. If i double escape ("\\") minus, then i have no results.

I have no idea, how searching performs, when query consists of these characters. Maybe i'm doing something wrong.

I tryed to use nGram filter in my custom analyzer, but it doesn't suite to requirements of search engine.

If anyone encountered with this problem, please, answer.

Answer 1

Default analyzer will remove all special characters from your data at indexing time. You could use the keyword analyzer or simply not analyze your data at indexing time:

curl -XPUT "http://localhost:9200/test/" -d ' {
    "mappings" : {
            "properties": {
                    "test_field": {
                            "type": "string",
                            "index": "not_analyzed"
                    }
            }
    }
} '