Prefix query

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Returns documents that contain a specific prefix in a provided field.

Example request

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The following search returns documents where the user.id field contains a term that begins with ki.

GET /_search
{
  "query": {
    "prefix": {
      "user.id": {
        "value": "ki"
      }
    }
  }
}

Top-level parameters for prefix

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<field>
(Required, object) Field you wish to search.

Parameters for <field>

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value
(Required, string) Beginning characters of terms you wish to find in the provided <field>.
rewrite
(Optional, string) Method used to rewrite the query. For valid values and more information, see the rewrite parameter.

Notes

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Short request example

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You can simplify the prefix query syntax by combining the <field> and value parameters. For example:

GET /_search
{
  "query": {
    "prefix" : { "user" : "ki" }
  }
}

Speed up prefix queries

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You can speed up prefix queries using the index_prefixes mapping parameter. If enabled, Elasticsearch indexes prefixes between 2 and 5 characters in a separate field. This lets Elasticsearch run prefix queries more efficiently at the cost of a larger index.

Allow expensive queries

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Prefix queries will not be executed if search.allow_expensive_queries is set to false. However, if index_prefixes are enabled, an optimised query is built which is not considered slow, and will be executed in spite of this setting.