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Plugin discovery documentation contained information about installing Elasticsearch 2.0 and installing an oracle JDK, both of which is no longer valid. While noticing that the instructions used cleartext HTTP to install packages, this commit replaces HTTPs links instead of HTTP where possible. In addition a few community links have been removed, as they do not seem to exist anymore.
104 lines
2.6 KiB
Text
104 lines
2.6 KiB
Text
[[query-dsl-fuzzy-query]]
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=== Fuzzy query
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++++
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<titleabbrev>Fuzzy</titleabbrev>
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++++
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Returns documents that contain terms similar to the search term, as measured by
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a https://en.wikipedia.org/wiki/Levenshtein_distance[Levenshtein edit distance].
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An edit distance is the number of one-character changes needed to turn one term
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into another. These changes can include:
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* Changing a character (**b**ox → **f**ox)
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* Removing a character (**b**lack → lack)
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* Inserting a character (sic → sic**k**)
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* Transposing two adjacent characters (**ac**t → **ca**t)
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To find similar terms, the `fuzzy` query creates a set of all possible
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variations, or expansions, of the search term within a specified edit distance.
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The query then returns exact matches for each expansion.
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[[fuzzy-query-ex-request]]
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==== Example requests
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[[fuzzy-query-ex-simple]]
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===== Simple example
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[source,console]
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----
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GET /_search
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{
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"query": {
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"fuzzy": {
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"user": {
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"value": "ki"
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}
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}
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}
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}
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----
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[[fuzzy-query-ex-advanced]]
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===== Example using advanced parameters
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[source,console]
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----
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GET /_search
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{
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"query": {
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"fuzzy": {
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"user": {
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"value": "ki",
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"fuzziness": "AUTO",
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"max_expansions": 50,
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"prefix_length": 0,
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"transpositions": true,
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"rewrite": "constant_score"
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}
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}
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}
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}
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----
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[[fuzzy-query-top-level-params]]
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==== Top-level parameters for `fuzzy`
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`<field>`::
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(Required, object) Field you wish to search.
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[[fuzzy-query-field-params]]
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==== Parameters for `<field>`
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`value`::
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(Required, string) Term you wish to find in the provided `<field>`.
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`fuzziness`::
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(Optional, string) Maximum edit distance allowed for matching. See <<fuzziness>>
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for valid values and more information.
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`max_expansions`::
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+
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--
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(Optional, integer) Maximum number of variations created. Defaults to `50`.
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WARNING: Avoid using a high value in the `max_expansions` parameter, especially
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if the `prefix_length` parameter value is `0`. High values in the
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`max_expansions` parameter can cause poor performance due to the high number of
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variations examined.
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--
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`prefix_length`::
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(Optional, integer) Number of beginning characters left unchanged when creating
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expansions. Defaults to `0`.
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`transpositions`::
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(Optional, boolean) Indicates whether edits include transpositions of two
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adjacent characters (ab → ba). Defaults to `true`.
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`rewrite`::
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(Optional, string) Method used to rewrite the query. For valid values and more
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information, see the <<query-dsl-multi-term-rewrite, `rewrite` parameter>>.
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==== Notes
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Fuzzy queries will not be executed if <<query-dsl-allow-expensive-queries, `search.allow_expensive_queries`>>
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is set to false.
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