Multi_match with phrase_prefix is not working although a token has the prefix in it

Elastic Search
3

It's because of the max_expansions value. By default it's set to 50. So when you send query with longer characters (eg. "202201") you will see the results. You can increase the max_expansion value the but it can hurt the performance.

See my screenshot, both queries are showing the results because I have only one doc in test index.

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See the notes from official documentation: Match phrase prefix query | Elasticsearch Guide [8.14] | Elastic

As a workaround you can choose one of the followings.

  1. Increase the max_expansion value in your query.
  2. Use edge_ngram tokenizer - This will also tune the query speed. (recommended)
  3. Use prefix query - there is no max_expansion limit for the prefix query but it can be slower than phrase_prefix.