OpenSearch/docs/reference/query-dsl/queries/multi-match-query.asciidoc

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[[query-dsl-multi-match-query]]
=== Multi Match Query
The `multi_match` query builds further on top of the `match` query by
allowing multiple fields to be specified. The idea here is to allow to
more easily build a concise match type query over multiple fields
instead of using a relatively more expressive query by using multiple
match queries within a `bool` query.
The structure of the query is a bit different. Instead of a nested json
object defining the query field, there is a top json level field for
defining the query fields. Example:
[source,js]
--------------------------------------------------
{
"multi_match" : {
"query" : "this is a test",
"fields" : [ "subject", "message" ]
}
}
--------------------------------------------------
The `multi_match` query creates either a `bool` or a `dis_max` top level
query. Each field is a query clause in this top level query. The query
clause contains the actual query (the specified 'type' defines what
query this will be). Each query clause is basically a `should` clause.
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[float]
==== Options
All options that apply on the `match` query also apply on the
`multi_match` query. The `match` query options apply only on the
individual clauses inside the top level query.
* `fields` - Fields to be used in the query.
* `use_dis_max` - Boolean indicating to either create a `dis_max` query
or a `bool` query. Defaults to `true`.
* `tie_breaker` - Multiplier value to balance the scores between lower
and higher scoring fields. Only applicable when `use_dis_max` is set to
true. Defaults to `0.0`.
The query accepts all the options that a regular `match` query accepts.
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==== Boosting
The `multi_match` query supports field boosting via `^` notation in the
fields json field.
[source,js]
--------------------------------------------------
{
"multi_match" : {
"query" : "this is a test",
"fields" : [ "subject^2", "message" ]
}
}
--------------------------------------------------
In the above example hits in the `subject` field are 2 times more
important than in the `message` field.