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

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[[query-dsl-term-query]]
=== Term Query
The `term` query finds documents that contain the *exact* term specified
in the inverted index. For instance:
[source,js]
--------------------------------------------------
POST _search
{
"query": {
"term" : { "user" : "Kimchy" } <1>
}
}
--------------------------------------------------
// CONSOLE
<1> Finds documents which contain the exact term `Kimchy` in the inverted index
of the `user` field.
A `boost` parameter can be specified to give this `term` query a higher
relevance score than another query, for instance:
[source,js]
--------------------------------------------------
GET _search
{
"query": {
"bool": {
"should": [
{
"term": {
"status": {
"value": "urgent",
"boost": 2.0 <1>
}
}
},
{
"term": {
"status": "normal" <2>
}
}
]
}
}
}
--------------------------------------------------
// CONSOLE
<1> The `urgent` query clause has a boost of `2.0`, meaning it is twice as important
as the query clause for `normal`.
<2> The `normal` clause has the default neutral boost of `1.0`.
A `term` query can also match against <<range, range data types>>.
.Why doesn't the `term` query match my document?
**************************************************
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String fields can be of type `text` (treated as full text, like the body of an
email), or `keyword` (treated as exact values, like an email address or a
zip code). Exact values (like numbers, dates, and keywords) have
the exact value specified in the field added to the inverted index in order
to make them searchable.
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However, `text` fields are `analyzed`. This means that their
values are first passed through an <<analysis,analyzer>> to produce a list of
terms, which are then added to the inverted index.
There are many ways to analyze text: the default
<<analysis-standard-analyzer,`standard` analyzer>> drops most punctuation,
breaks up text into individual words, and lower cases them. For instance,
the `standard` analyzer would turn the string ``Quick Brown Fox!'' into the
terms [`quick`, `brown`, `fox`].
This analysis process makes it possible to search for individual words
within a big block of full text.
The `term` query looks for the *exact* term in the field's inverted index --
it doesn't know anything about the field's analyzer. This makes it useful for
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looking up values in keyword fields, or in numeric or date
fields. When querying full text fields, use the
<<query-dsl-match-query,`match` query>> instead, which understands how the field
has been analyzed.
To demonstrate, try out the example below. First, create an index, specifying the field mappings, and index a document:
[source,js]
--------------------------------------------------
Update the default for include_type_name to false. (#37285) * Default include_type_name to false for get and put mappings. * Default include_type_name to false for get field mappings. * Add a constant for the default include_type_name value. * Default include_type_name to false for get and put index templates. * Default include_type_name to false for create index. * Update create index calls in REST documentation to use include_type_name=true. * Some minor clean-ups around the get index API. * In REST tests, use include_type_name=true by default for index creation. * Make sure to use 'expression == false'. * Clarify the different IndexTemplateMetaData toXContent methods. * Fix FullClusterRestartIT#testSnapshotRestore. * Fix the ml_anomalies_default_mappings test. * Fix GetFieldMappingsResponseTests and GetIndexTemplateResponseTests. We make sure to specify include_type_name=true during xContent parsing, so we continue to test the legacy typed responses. XContent generation for the typeless responses is currently only covered by REST tests, but we will be adding unit test coverage for these as we implement each typeless API in the Java HLRC. This commit also refactors GetMappingsResponse to follow the same appraoch as the other mappings-related responses, where we read include_type_name out of the xContent params, instead of creating a second toXContent method. This gives better consistency in the response parsing code. * Fix more REST tests. * Improve some wording in the create index documentation. * Add a note about types removal in the create index docs. * Fix SmokeTestMonitoringWithSecurityIT#testHTTPExporterWithSSL. * Make sure to mention include_type_name in the REST docs for affected APIs. * Make sure to use 'expression == false' in FullClusterRestartIT. * Mention include_type_name in the REST templates docs.
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PUT my_index?include_type_name=true
{
"mappings": {
"_doc": {
"properties": {
"full_text": {
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"type": "text" <1>
},
"exact_value": {
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"type": "keyword" <2>
}
}
}
}
}
PUT my_index/_doc/1
{
"full_text": "Quick Foxes!", <3>
"exact_value": "Quick Foxes!" <4>
}
--------------------------------------------------
// CONSOLE
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<1> The `full_text` field is of type `text` and will be analyzed.
<2> The `exact_value` field is of type `keyword` and will NOT be analyzed.
<3> The `full_text` inverted index will contain the terms: [`quick`, `foxes`].
<4> The `exact_value` inverted index will contain the exact term: [`Quick Foxes!`].
Now, compare the results for the `term` query and the `match` query:
[source,js]
--------------------------------------------------
GET my_index/_search
{
"query": {
"term": {
"exact_value": "Quick Foxes!" <1>
}
}
}
GET my_index/_search
{
"query": {
"term": {
"full_text": "Quick Foxes!" <2>
}
}
}
GET my_index/_search
{
"query": {
"term": {
"full_text": "foxes" <3>
}
}
}
GET my_index/_search
{
"query": {
"match": {
"full_text": "Quick Foxes!" <4>
}
}
}
--------------------------------------------------
// CONSOLE
// TEST[continued]
<1> This query matches because the `exact_value` field contains the exact
term `Quick Foxes!`.
<2> This query does not match, because the `full_text` field only contains
the terms `quick` and `foxes`. It does not contain the exact term
`Quick Foxes!`.
<3> A `term` query for the term `foxes` matches the `full_text` field.
<4> This `match` query on the `full_text` field first analyzes the query string,
then looks for documents containing `quick` or `foxes` or both.
**************************************************