elasticsearchHow can I perform a case-insensitive wildcard search using Elasticsearch?

A wildcard search in Elasticsearch using a case-insensitive query is possible by using the lowercase_expanded_terms parameter.

Example code

GET /my_index/_search
{
  "query": {
    "wildcard": {
      "my_field": {
        "value": "*test*",
        "lowercase_expanded_terms": false
      }
    }
  }
}

This query will return all documents that contain the term test in the my_field field, regardless of the case.

The lowercase_expanded_terms parameter is set to false by default, so it is not necessary to set it explicitly.

Code explanation

• GET /my_index/_search - the endpoint used to send the query to Elasticsearch
• "query": { "wildcard": { "my_field": { "value": "*test*" - the wildcard query used to perform the search, with my_field as the field to search in and *test* as the value to search for
• "lowercase_expanded_terms": false - the parameter used to make the search case-insensitive

Helpful links

• Elasticsearch Wildcard Query Documentation
• Elasticsearch Case-Insensitive Wildcard Queries

Edit this code on GitHub