Contains Query or Partial matching in Elasticsearch

Question

I'm looking to search a word say "amend" which may be present in data as "amending", "amendment" or even "*amend". Which is the best method to search words like these? I know wildcard can achieve this but I am restricted to not using it due to my other part of the code. What are the different ways which provides better search performance?

Answer 1

You can implement this using query_string feature of elasticsearch. Assuming that you use default standard analyzer.

{  
   "query":{  
      "query_string":{  
         "default_field":"Customer",
         "query":"*Jo*"
      }
   }
} 

You can add multiple fields as well as shown in the below query

{  
   "query":{  
      "query_string":{  
         "fields":[  
            "Customer",
            "Name"
         ],
         "query":"*Jo*"
      }
   }
}

Answer 2

There is various way:

As you mention you cannot use wildcard, Then go for query_string

{  
   "query":{  
      "query_string":{  
         "default_field":"text",
         "query":"*amend"
      }
   }
}

Second you can use n-gram tokenizer. You can check here https://www.elastic.co/guide/en/elasticsearch/reference/current/analysis-ngram-tokenizer.html

It will breaks your value "amending" to words like ["ame","men","end" ... etc]

Once you done with applying n-gram tokeinzer, Start indexing your data.

You can query like below:

{"query":{"term":{"text":"amend"}}}

You will get your output result.