Kibana Query Language

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The Kibana Query Language (KQL) is a simple text-based query language for filtering data.

  • KQL only filters data, and has no role in aggregating, transforming, or sorting data.
  • KQL is not to be confused with the Lucene query language, which has a different feature set.

Use KQL to filter documents where a value for a field exists, matches a given value, or is within a given range.

Filter for documents where a field exists

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To filter documents for which an indexed value exists for a given field, use the * operator. For example, to filter for documents where the http.request.method field exists, use the following syntax:

http.request.method: *

This checks for any indexed value, including an empty string.

Filter for documents that match a value

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Use KQL to filter for documents that match a specific number, text, date, or boolean value. For example, to filter for documents where the http.request.method is GET, use the following query:

http.request.method: GET

The field parameter is optional. If not provided, all fields are searched for the given value. For example, to search all fields for “Hello”, use the following:

Hello

When querying keyword, numeric, date, or boolean fields, the value must be an exact match, including punctuation and case. However, when querying text fields, Elasticsearch analyzes the value provided according to the field’s mapping settings. For example, to search for documents where http.request.body.content (a text field) contains the text “null pointer”:

http.request.body.content: null pointer

Because this is a text field, the order of these search terms does not matter, and even documents containing “pointer null” are returned. To search text fields where the terms are in the order provided, surround the value in quotation marks, as follows:

http.request.body.content: "null pointer"

Certain characters must be escaped by a backslash (unless surrounded by quotes). For example, to search for documents where http.request.referrer is https://example.com, use either of the following queries:

http.request.referrer: "https://example.com"
http.request.referrer: https\://example.com

You must escape following characters:

\():<>"*

Filter for documents within a range

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To search documents that contain terms within a provided range, use KQL’s range syntax. For example, to search for all documents for which http.response.bytes is less than 10000, use the following syntax:

http.response.bytes < 10000

To search for an inclusive range, combine multiple range queries. For example, to search for documents where http.response.bytes is greater than 10000 but less than or equal to 20000, use the following syntax:

http.response.bytes > 10000 and http.response.bytes <= 20000

You can also use range syntax for string values, IP addresses, and timestamps. For example, to search for documents earlier than two weeks ago, use the following syntax:

@timestamp < now-2w

For more examples on acceptable date formats, refer to Date Math.

Filter for documents using wildcards

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To search for documents matching a pattern, use the wildcard syntax. For example, to find documents where http.response.status_code begins with a 4, use the following syntax:

http.response.status_code: 4*

By default, leading wildcards are not allowed for performance reasons. You can modify this with the query:allowLeadingWildcards advanced setting.

Only * is currently supported. This matches zero or more characters.

Negating a query

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To negate or exclude a set of documents, use the not keyword (not case-sensitive). For example, to filter documents where the http.request.method is not GET, use the following query:

NOT http.request.method: GET

Combining multiple queries

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To combine multiple queries, use the and/or keywords (not case-sensitive). For example, to find documents where the http.request.method is GET or the http.response.status_code is 400, use the following query:

http.request.method: GET OR http.response.status_code: 400

Similarly, to find documents where the http.request.method is GET and the http.response.status_code is 400, use this query:

http.request.method: GET AND http.response.status_code: 400

To specify precedence when combining multiple queries, use parentheses. For example, to find documents where the http.request.method is GET and the http.response.status_code is 200, or the http.request.method is POST and http.response.status_code is 400, use the following:

(http.request.method: GET AND http.response.status_code: 200) OR
(http.request.method: POST AND http.response.status_code: 400)

You can also use parentheses for shorthand syntax when querying multiple values for the same field. For example, to find documents where the http.request.method is GET, POST, or DELETE, use the following:

http.request.method: (GET OR POST OR DELETE)

Matching multiple fields

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Wildcards can also be used to query multiple fields. For example, to search for documents where any sub-field of datastream contains “logs”, use the following:

datastream.*: logs

When using wildcards to query multiple fields, errors might occur if the fields are of different types. For example, if datastream.* matches both numeric and string fields, the above query will result in an error because numeric fields cannot be queried for string values.

Querying nested fields

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Querying nested fields requires a special syntax. Consider the following document, where user is a nested field:

{
  "user" : [
    {
      "first" : "John",
      "last" :  "Smith"
    },
    {
      "first" : "Alice",
      "last" :  "White"
    }
  ]
}

To find documents where a single value inside the user array contains a first name of “Alice” and last name of “White”, use the following:

user:{ first: "Alice" and last: "White" }

Because nested fields can be inside other nested fields, you must specify the full path of the nested field you want to query. For example, consider the following document where user and names are both nested fields:

{
  "user": [
    {
      "names": [
        {
          "first": "John",
          "last": "Smith"
        },
        {
          "first": "Alice",
          "last": "White"
        }
      ]
    }
  ]
}

To find documents where a single value inside the user.names array contains a first name of “Alice” and last name of “White”, use the following:

user.names:{ first: "Alice" and last: "White" }