500 error in multi match query for field without position data

[carlosdelest]

Elasticsearch Version

8.x / 9.x

Installed Plugins

No response

Java Version

bundled

OS Version

any

Problem Description

Using the mapping and analyzers described in the Steps to Reproduce section returns a 500 status code:

{
    "error": {
        "root_cause": [
            {
                "type": "illegal_state_exception",
                "reason": "field \"content.joined\" was indexed without position data; cannot run MultiPhraseQuery (phrase=content.joined:\"(hello helloworld) world\")",
                "stack_trace": "org.elasticsearch.ElasticsearchException$1: field \"content.joined\" was indexed without position data; cannot run MultiPhraseQuery (phrase=content.joined:\"(hello helloworld) world\")\n\tat org.elasticsearch.server@9.1.0-SNAPSHOT/org.elasticsearch.ElasticsearchException.guessRootCauses(ElasticsearchException.java:725)\n\tat org.elasticsearch.server@9.1.0-SNAPSHOT/org.elasticsearch.action.search.SearchPhaseExecutionException.guessRootCauses(SearchPhaseExecutionException.java:167)\n\tat org.elasticsearch.server@9.1.0-SNAPSHOT/org.elasticsearch.ElasticsearchException.guessRootCauses(ElasticsearchException.java:707)\n\tat org.elasticsearch.server@9.1.0-SNAPSHOT/org.elasticsearch.ElasticsearchException.generateFailureXContent(ElasticsearchException.java:639)\n\tat org.elasticsearch.server@9.1.0-SNAPSHOT/org.elasticsearch.rest.RestResponse.build(RestResponse.java:202)\n\tat org.elasticsearch.server@9.1.0-SNAPSHOT/org.elasticsearch.rest.RestResponse.<init>(RestResponse.java:161)\n\tat org.elasticsearch.server@9.1.0-SNAPSHOT/org.elasticsearch.rest.RestResponse.<init>(RestResponse.java:122)\n\tat org.elasticsearch.server@9.1.0-SNAPSHOT/org.elasticsearch.rest.action.RestActionListener.onFailure(RestActionListener.java:54)\n\tat org.elasticsearch.server@9.1.0-SNAPSHOT/org.elasticsearch.rest.action.RestCancellableNodeClient$1.onFailure(RestCancellableNodeClient.java:97)\n\tat org.elasticsearch.server@9.1.0-SNAPSHOT/org.elasticsearch.action.ActionListenerImplementations.safeAcceptException(ActionListenerImplementations.java:78)\n
    },
    "status": 500
}

This is unexpected, as this should be a 400 status code instead.

Removing the bigram analyzer from the mapping below results in a 400 when doing the same query.

Steps to Reproduce

PUT test-multi-match
{
    "mappings": {
      "properties": {
        "content": {
          "type": "text",
          "fields": {
            "joined": {
              "type": "text",
              "index_options": "freqs",
              "search_analyzer": "q_text_bigram"
            }
          }
        }
      }
    },
    "settings": {
        "analysis": {
          "filter": {
            "bigram_joiner_unigrams": {
              "max_shingle_size": "2",
              "token_separator": "",
              "output_unigrams": "true",
              "type": "shingle"
            }
          },
          "analyzer": {          
            "q_text_bigram": {
              "filter": [
                "bigram_joiner_unigrams"
              ],
              "type": "custom",
              "tokenizer": "standard"
            }    
          }
        }
      }    
    }
}

PUT test-multi-match/_doc/1
{
  "content": "hello world"
}

Returns a 500 status code when executing:

GET test-multi-match/_search?error_trace=true
{
  "query": {
    "multi_match": {
      "query": "hello world",
      "type": "phrase",
      "fields": ["content.joined"]
    }
  }
}

Logs (if relevant)

No response

[elasticsearchmachine]

Pinging @elastic/es-search-foundations (Team:Search Foundations)

[elasticsearchmachine]

Pinging @elastic/es-search-relevance (Team:Search Relevance)