OpenSearch/docs/reference/search/search.asciidoc

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[[search-search]]
=== Search API
++++
<titleabbrev>Search</titleabbrev>
++++
Returns search hits that match the query defined in the request.
[source,console]
----
GET /twitter/_search
----
// TEST[setup:twitter]
[[search-search-api-request]]
==== {api-request-title}
`GET /<index>/_search`
`GET /_search`
`POST /<index>/_search`
`POST /_search`
[[search-search-api-desc]]
==== {api-description-title}
Allows you to execute a search query and get back search hits that match the
query. You can provide search queries using the <<search-api-query-params-q,`q`
query string parameter>> or <<search-request-body,request body>>.
[[search-search-api-path-params]]
==== {api-path-parms-title}
include::{docdir}/rest-api/common-parms.asciidoc[tag=index]
[[search-search-api-query-params]]
==== {api-query-parms-title}
include::{docdir}/rest-api/common-parms.asciidoc[tag=allow-no-indices]
+
Defaults to `true`.
[[search-partial-responses]]
`allow_partial_search_results`::
(Optional, boolean)
If `true`, returns partial results if there are request timeouts or
<<shard-failures,shard failures>>. If `false`, returns an error with
no partial results. Defaults to `true`.
+
To override the default for this field, set the
`search.default_allow_partial_results` cluster setting to `false`.
`batched_reduce_size`::
(Optional, integer) The number of shard results that should be reduced at once
on the coordinating node. This value should be used as a protection mechanism
to reduce the memory overhead per search request if the potential number of
shards in the request can be large. Defaults to `512`.
[[ccs-minimize-roundtrips]]
`ccs_minimize_roundtrips`::
(Optional, boolean) If `true`, network round-trips between the
coordinating node and the remote clusters are minimized when executing
{ccs} (CCS) requests. See <<ccs-network-delays>>. Defaults to `true`.
`docvalue_fields`::
(Optional, string) A comma-separated list of fields to return as the docvalue
representation of a field for each hit.
include::{docdir}/rest-api/common-parms.asciidoc[tag=expand-wildcards]
+
Defaults to `open`.
`explain`::
(Optional, boolean) If `true`, returns detailed information about score
computation as part of a hit. Defaults to `false`.
include::{docdir}/rest-api/common-parms.asciidoc[tag=from]
+
--
[IMPORTANT]
====
You can also specify this value using the `from` request body parameter. If
both parameters are specified, only the query parameter is used.
====
--
`ignore_throttled`::
(Optional, boolean) If `true`, concrete, expanded or aliased indices will be
ignored when frozen. Defaults to `false`.
include::{docdir}/rest-api/common-parms.asciidoc[tag=index-ignore-unavailable]
`max_concurrent_shard_requests`::
(Optional, integer) Defines the number of concurrent shard requests per node
this search executes concurrently. This value should be used to limit the
impact of the search on the cluster in order to limit the number of concurrent
shard requests. Defaults to `5`.
`pre_filter_shard_size`::
(Optional, integer) Defines a threshold that enforces a pre-filter roundtrip
to prefilter search shards based on query rewriting if the number of shards
the search request expands to exceeds the threshold. This filter roundtrip can
limit the number of shards significantly if for instance a shard can not match
any documents based on its rewrite method ie. if date filters are mandatory
to match but the shard bounds and the query are disjoint.
When unspecified, the pre-filter phase is executed if any of these conditions is met:
- The request targets more than `128` shards.
- The request targets one or more read-only index.
- The primary sort of the query targets an indexed field.
`preference`::
(Optional, string) Specifies the node or shard the operation should be
performed on. Random by default.
[[search-api-query-params-q]]
include::{docdir}/rest-api/common-parms.asciidoc[tag=search-q]
+
--
You can use the `q` parameter to run a query parameter search. Query parameter
searches do not support the full {es} <<query-dsl,Query DSL>> but are handy for
testing.
[IMPORTANT]
====
The `q` parameter overrides the <<search-api-request-body-query,`query`>>
parameter in the request body. If both parameters are specified, documents
matching the `query` request body parameter are not returned.
====
--
`request_cache`::
(Optional, boolean) If `true`, the caching of search results is enabled for
requests where `size` is `0`. See <<shard-request-cache>>. Defaults to index
level settings.
`rest_total_hits_as_int`::
(Optional, boolean) Indicates whether hits.total should be rendered as an
integer or an object in the rest search response. Defaults to `false`.
`routing`::
(Optional, <<time-units, time units>>) Specifies how long a consistent view of
the index should be maintained for scrolled search.
include::{docdir}/rest-api/common-parms.asciidoc[tag=search_type]
`seq_no_primary_term`::
(Optional, boolean) If `true`, returns sequence number and primary term of the
last modification of each hit.
`size`::
(Optional, integer) Defines the number of hits to return. Defaults to `10`.
+
--
[IMPORTANT]
====
You can also specify this value using the `size` request body parameter. If
both parameters are specified, only the query parameter is used.
====
--
`sort`::
(Optional, string) A comma-separated list of <field>:<direction> pairs.
`_source`::
(Optional, boolean)
If `true`, the response includes the `_source` of matching documents under
`hits`. Defaults to `true`.
include::{docdir}/rest-api/common-parms.asciidoc[tag=source_excludes]
include::{docdir}/rest-api/common-parms.asciidoc[tag=source_includes]
`stats`::
(Optional, string) Specific `tag` of the request for logging and statistical
purposes.
`stored_fields`::
(Optional, string) A comma-separated list of stored fields to return as part
of a hit. If no fields are specified, no stored fields are included in the
response.
`suggest_field`::
(Optional, string) Specifies which field to use for suggestions.
`suggest_text`::
(Optional, string) The source text for which the suggestions should be
returned.
include::{docdir}/rest-api/common-parms.asciidoc[tag=terminate_after]
+
--
Defaults to `0`, which does not terminate query execution early.
[IMPORTANT]
====
You can also specify this value using the `terminate_after` request body
parameter. If both parameters are specified, only the query parameter is used.
====
--
`timeout`::
+
--
(Optional, <<time-units, time units>>) Specifies the period of time to wait
for a response. If no response is received before the timeout expires, the
request fails and returns an error. Defaults to no timeout.
[IMPORTANT]
====
You can also specify this value using the `timeout` request body
parameter. If both parameters are specified, only the query parameter is used.
====
--
`track_scores`::
(Optional, boolean) If `true`, calculate and return document scores, even if
the scores are not used for sorting. Defaults to `false`.
`track_total_hits`::
(Optional, integer or boolean)
Number of hits matching the query to count accurately. Defaults to `10000`.
+
If `true`, the default value is used. If `false`, the response does not
include the total number of hits matching the query.
`typed_keys`::
(Optional, boolean) If `true`, aggregation and suggester names are be prefixed
by their respective types in the response. Defaults to `true`.
`version`::
(Optional, boolean)
If `true`, returns document version as part of a hit. Defaults to `false.
[[search-search-api-request-body]]
==== {api-request-body-title}
include::{docdir}/rest-api/common-parms.asciidoc[tag=from]
+
--
[IMPORTANT]
====
You can also specify this value using the `from` query parameter. If both
parameters are specified, only the query parameter is used.
====
--
[[search-api-request-body-query]]
`query`::
(Optional, <<query-dsl,query object>>) Defines the search definition using the
<<query-dsl,Query DSL>>.
`size`::
(Optional, integer) The number of hits to return. Defaults to `10`.
+
--
[IMPORTANT]
====
You can also specify this value using the `size` query parameter. If both
parameters are specified, only the query parameter is used.
====
--
include::{docdir}/rest-api/common-parms.asciidoc[tag=terminate_after]
+
--
Defaults to `0`, which does not terminate query execution early.
[IMPORTANT]
====
You can also specify this value using the `terminate_after` query parameter. If
both parameters are specified, only the query parameter is used.
====
--
`timeout`::
+
--
(Optional, <<time-units, time units>>) Specifies the period of time to wait
for a response. If no response is received before the timeout expires, the
request fails and returns an error. Defaults to no timeout.
[IMPORTANT]
====
You can also specify this value using the `timeout` query parameter. If both
parameters are specified, only the query parameter is used.
====
--
[role="child_attributes"]
[[search-api-response-body]]
==== {api-response-body-title}
`took`::
+
--
(integer)
Milliseconds it took {es} to execute the request.
This value is calculated by measuring the time elapsed
between receipt of a request on the coordinating node
and the time at which the coordinating node is ready to send the response.
Took time includes:
* Communication time between the coordinating node and data nodes
* Time the request spends in the `search` <<modules-threadpool,thread pool>>,
queued for execution
* Actual execution time
Took time does *not* include:
* Time needed to send the request to {es}
* Time needed to serialize the JSON response
* Time needed to send the response to a client
--
`timed_out`::
(boolean)
If `true`,
the request timed out before completion;
returned results may be partial or empty.
`_shards`::
(object)
Contains a count of shards used for the request.
+
.Properties of `_shards`
[%collapsible%open]
====
`total`::
(integer)
Total number of shards that require querying,
including unallocated shards.
`successful`::
(integer)
Number of shards that executed the request successfully.
`skipped`::
(integer)
Number of shards that skipped the request because a lightweight check
helped realize that no documents could possibly match on this shard. This
typically happens when a search request includes a range filter and the
shard only has values that fall outside of that range.
`failed`::
(integer)
Number of shards that failed to execute the request. Note that shards
that are not allocated will be considered neither successful nor failed.
Having `failed+successful` less than `total` is thus an indication that
some of the shards were not allocated.
====
`hits`::
(object)
Contains returned documents and metadata.
+
.Properties of `hits`
[%collapsible%open]
====
`total`::
(object)
Metadata about the number of returned documents.
+
.Properties of `total`
[%collapsible%open]
=====
`value`::
(integer)
Total number of returned documents.
`relation`::
(string)
Indicates whether the number of returned documents in the `value`
parameter is accurate or a lower bound.
+
.Values of `relation`:
[%collapsible%open]
======
`eq`:: Accurate
`gte`:: Lower bound, including returned documents
======
=====
`max_score`::
(float)
Highest returned <<search-api-response-body-score,document `_score`>>.
+
This value is `null` for requests that do not sort by `_score`.
[[search-api-response-body-hits]]
`hits`::
(array of objects)
Array of returned document objects.
+
.Properties of `hits` objects
[%collapsible%open]
=====
`_index`::
(string)
Name of the index containing the returned document.
`_type`::
deprecated:[6.0.0, Mapping types are deprecated and will be removed in 8.0. See <<removal-of-types>>.]
(string)
Mapping type of the returned document.
`_id`::
(string)
Unique identifier for the returned document.
This ID is only unique within the returned index.
[[search-api-response-body-score]]
`_score`::
(float)
Positive 32-bit floating point number used to determine the relevance of the
returned document.
[[search-api-response-body-source]]
`_source`::
(object)
Original JSON body passed for the document at index time.
=====
====
[[search-search-api-example]]
==== {api-examples-title}
[[search-api-specific-ex]]
===== Search an index using the `q` query parameter
[source,console]
----
GET /twitter/_search?q=user:kimchy
----
// TEST[continued]
The API returns the following response:
[source,console-result]
----
{
"took" : 5,
"timed_out" : false,
"_shards" : {
"total" : 1,
"successful" : 1,
"skipped" : 0,
"failed" : 0
},
"hits" : {
"total" : {
"value" : 1,
"relation" : "eq"
},
"max_score" : 1.3862942,
"hits" : [
{
"_index" : "twitter",
"_type" : "_doc",
"_id" : "0",
"_score" : 1.3862942,
"_source" : {
"date" : "2009-11-15T14:12:12",
"likes" : 0,
"message" : "trying out Elasticsearch",
"user" : "kimchy"
}
}
]
}
}
----
// TESTRESPONSE[s/"took" : 5/"took": $body.took/]
[[search-multi-index]]
===== Search several indices using the `q` query parameter
[source,console]
----
GET /kimchy,elasticsearch/_search?q=user:kimchy
----
// TEST[s/^/PUT kimchy\nPUT elasticsearch\n/]
[[search-api-all-ex]]
===== Search all indices using the `q` query parameter
To search all indices in a cluster,
omit the `<index>` parameter.
[source,console]
----
GET /_search?q=user:kimchy
----
// TEST[continued]
Alternatively,
you can use the `_all` or `*` value in the `<index>` parameter.
[source,console]
----
GET /_all/_search?q=user:kimchy
----
// TEST[continued]
[source,console]
----
GET /*/_search?q=user:kimchy
----
// TEST[continued]
[[search-request-body-api-example]]
===== Search an index using the `query` request body parameter
[source,console]
--------------------------------------------------
GET /twitter/_search
{
"query" : {
"term" : { "user" : "kimchy" }
}
}
--------------------------------------------------
// TEST[setup:twitter]
The API returns the following response:
[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": 1.3862942,
"hits" : [
{
"_index" : "twitter",
"_type" : "_doc",
"_id" : "0",
"_score": 1.3862942,
"_source" : {
"user" : "kimchy",
"message": "trying out Elasticsearch",
"date" : "2009-11-15T14:12:12",
"likes" : 0
}
}
]
}
}
--------------------------------------------------
// TESTRESPONSE[s/"took": 1/"took": $body.took/]