OpenSearch/docs/reference/query-dsl/term-query.asciidoc

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[[query-dsl-term-query]]
=== Term query
++++
<titleabbrev>Term</titleabbrev>
++++
Returns documents that contain an *exact* term in a provided field.
You can use the `term` query to find documents based on a precise value such as
a price, a product ID, or a username.
[WARNING]
====
Avoid using the `term` query for <<text, `text`>> fields.
By default, {es} changes the values of `text` fields as part of <<analysis,
analysis>>. This can make finding exact matches for `text` field values
difficult.
To search `text` field values, use the <<query-dsl-match-query,`match`>> query
instead.
====
[[term-query-ex-request]]
==== Example request
[source,console]
----
GET /_search
{
"query": {
"term": {
"user": {
"value": "Kimchy",
"boost": 1.0
}
}
}
}
----
[[term-top-level-params]]
==== Top-level parameters for `term`
`<field>`::
(Required, object) Field you wish to search.
[[term-field-params]]
==== Parameters for `<field>`
`value`::
(Required, string) Term you wish to find in the provided `<field>`. To return a
document, the term must exactly match the field value, including whitespace and
capitalization.
`boost`::
(Optional, float) Floating point number used to decrease or increase the
<<relevance-scores,relevance scores>> of a query. Defaults to `1.0`.
+
You can use the `boost` parameter to adjust relevance scores for searches
containing two or more queries.
+
Boost values are relative to the default value of `1.0`. A boost value between
`0` and `1.0` decreases the relevance score. A value greater than `1.0`
increases the relevance score.
[[term-query-notes]]
==== Notes
[[avoid-term-query-text-fields]]
===== Avoid using the `term` query for `text` fields
By default, {es} changes the values of `text` fields during analysis. For
example, the default <<analysis-standard-analyzer, standard analyzer>> changes
`text` field values as follows:
* Removes most punctuation
* Divides the remaining content into individual words, called
<<analysis-tokenizers, tokens>>
* Lowercases the tokens
To better search `text` fields, the `match` query also analyzes your provided
search term before performing a search. This means the `match` query can search
`text` fields for analyzed tokens rather than an exact term.
The `term` query does *not* analyze the search term. The `term` query only
searches for the *exact* term you provide. This means the `term` query may
return poor or no results when searching `text` fields.
To see the difference in search results, try the following example.
. Create an index with a `text` field called `full_text`.
+
--
[source,console]
----
PUT my_index
{
"mappings" : {
"properties" : {
"full_text" : { "type" : "text" }
}
}
}
----
--
. Index a document with a value of `Quick Brown Foxes!` in the `full_text`
field.
+
--
[source,console]
----
PUT my_index/_doc/1
{
"full_text": "Quick Brown Foxes!"
}
----
// TEST[continued]
Because `full_text` is a `text` field, {es} changes `Quick Brown Foxes!` to
`[quick, brown, fox]` during analysis.
--
. Use the `term` query to search for `Quick Brown Foxes!` in the `full_text`
field. Include the `pretty` parameter so the response is more readable.
+
--
[source,console]
----
GET my_index/_search?pretty
{
"query": {
"term": {
"full_text": "Quick Brown Foxes!"
}
}
}
----
// TEST[continued]
Because the `full_text` field no longer contains the *exact* term `Quick Brown
Foxes!`, the `term` query search returns no results.
--
. Use the `match` query to search for `Quick Brown Foxes!` in the `full_text`
field.
+
--
////
[source,console]
----
POST my_index/_refresh
----
// TEST[continued]
////
[source,console]
----
GET my_index/_search?pretty
{
"query": {
"match": {
"full_text": "Quick Brown Foxes!"
}
}
}
----
// TEST[continued]
Unlike the `term` query, the `match` query analyzes your provided search term,
`Quick Brown Foxes!`, before performing a search. The `match` query then returns
any documents containing the `quick`, `brown`, or `fox` tokens in the
`full_text` field.
Here's the response for the `match` query search containing the indexed document
in the results.
[source,console-result]
----
{
"took" : 1,
"timed_out" : false,
"_shards" : {
"total" : 1,
"successful" : 1,
"skipped" : 0,
"failed" : 0
},
"hits" : {
"total" : {
"value" : 1,
"relation" : "eq"
},
"max_score" : 0.8630463,
"hits" : [
{
"_index" : "my_index",
"_type" : "_doc",
"_id" : "1",
"_score" : 0.8630463,
"_source" : {
"full_text" : "Quick Brown Foxes!"
}
}
]
}
}
----
// TESTRESPONSE[s/"took" : 1/"took" : $body.took/]
--