[[query-dsl-match-query-phrase-prefix]] === Match Phrase Prefix Query The `match_phrase_prefix` is the same as `match_phrase`, except that it allows for prefix matches on the last term in the text. For example: [source,js] -------------------------------------------------- GET /_search { "query": { "match_phrase_prefix" : { "message" : "quick brown f" } } } -------------------------------------------------- // CONSOLE It accepts the same parameters as the phrase type. In addition, it also accepts a `max_expansions` parameter (default `50`) that can control to how many prefixes the last term will be expanded. It is highly recommended to set it to an acceptable value to control the execution time of the query. For example: [source,js] -------------------------------------------------- GET /_search { "query": { "match_phrase_prefix" : { "message" : { "query" : "quick brown f", "max_expansions" : 10 } } } } -------------------------------------------------- // CONSOLE [IMPORTANT] =================================================== The `match_phrase_prefix` query is a poor-man's autocomplete. It is very easy to use, which let's you get started quickly with _search-as-you-type_ but it's results, which usually are good enough, can sometimes be confusing. Consider the query string `quick brown f`. This query works by creating a phrase query out of `quick` and `brown` (i.e. the term `quick` must exist and must be followed by the term `brown`). Then it looks at the sorted term dictionary to find the first 50 terms that begin with `f`, and adds these terms to the phrase query. The problem is that the first 50 terms may not include the term `fox` so the phase `quick brown fox` will not be found. This usually isn't a problem as the user will continue to type more letters until the word they are looking for appears. For better solutions for _search-as-you-type_ see the <> and {guide}/_index_time_search_as_you_type.html[Index-Time Search-as-You-Type]. ===================================================