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.id": {
"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.
`case_insensitive`::
(Optional, boolean) allows ASCII case insensitive matching of the
value with the indexed field values when set to true. Default is false which means
the case sensitivity of matching depends on the underlying field's mapping
[[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-000001
{
"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-000001/_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-000001/_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-000001/_refresh
----
// TEST[continued]
////
[source,console]
----
GET my-index-000001/_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-000001",
"_type" : "_doc",
"_id" : "1",
"_score" : 0.8630463,
"_source" : {
"full_text" : "Quick Brown Foxes!"
}
}
]
}
}
----
// TESTRESPONSE[s/"took" : 1/"took" : $body.took/]
--