OpenSearch/docs/reference/search/search.asciidoc

[[search-search]]
=== Search API
++++
<titleabbrev>Search</titleabbrev>
++++

Returns search hits that match the query defined in the request.

[source,console]
----
GET /my-index-000001/_search
----
// TEST[setup:my_index]

[[search-search-api-request]]
==== {api-request-title}

`GET /<target>/_search`

`GET /_search`

`POST /<target>/_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}

`<target>`::
(Optional, string)
Comma-separated list of data streams, indices, and index aliases to search.
Wildcard (`*`) expressions are supported.
+
To search all data streams and indices in a cluster, omit this parameter or use
`_all` or `*`.

[role="child_attributes"]
[[search-search-api-query-params]]
==== {api-query-parms-title}

IMPORTANT: Several options for this API can be specified using a query parameter
or a request body parameter. If both parameters are specified, only the query
parameter is used.

include::{es-repo-dir}/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::{es-repo-dir}/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::{es-repo-dir}/rest-api/common-parms.asciidoc[tag=from]
+
--
By default, you cannot page through more than 10,000 documents using the `from`
and `size` parameters. This limit is set using the
<<index-max-result-window,`index.max_result_window`>> index setting.

Deep paging or requesting many results at once can result in slow searches.
Results are sorted before being returned. Because search requests usually span
multiple shards, each shard must generate its own sorted results. These separate
results must then be combined and sorted to ensure that the overall order is
correct.

As an alternative to deep paging, we recommend using
<<scroll-search-results,scroll>> or the
<<search-after,`search_after`>> parameter.
--

`ignore_throttled`::
(Optional, boolean) If `true`, concrete, expanded or aliased indices will be
ignored when frozen. Defaults to `true`.

include::{es-repo-dir}/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.

[[search-preference]]
`preference`::
(Optional, string)
Nodes and shards used for the search. By default, {es} selects from eligible
nodes and shards using <<search-adaptive-replica,adaptive replica selection>>,
accounting for <<shard-allocation-awareness,allocation awareness>>.
+
.Valid values for `preference`
[%collapsible%open]
====
`_only_local`::
Run the search only on shards on the local node.

`_local`::
If possible, run the search on shards on the local node. If not, select shards
using the default method.

`_only_nodes:<node-id>,<node-id>`::
Run the search on only the specified nodes IDs. If suitable shards exist on more
than one selected nodes, use shards on those nodes using the default method. If
none of the specified nodes are available, select shards from any available node
using the default method.

`_prefer_nodes:<node-id>,<node-id>`::
If possible, run the search on the specified nodes IDs. If not, select shards
using the default method.

`_shards:<shard>,<shard>`::
Run the search only on the specified shards. This value can be combined with
other `preference` values, but this value must come first. For example:
`_shards:2,3|_local`

<custom-string>::
Any string that does not start with `_`. If the cluster state and selected
shards do not change, searches using the same `<custom-string>` value are routed
to the same shards in the same order.
====


[[search-api-query-params-q]]
include::{es-repo-dir}/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 <<request-body-search-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`.

include::{es-repo-dir}/rest-api/common-parms.asciidoc[tag=routing]

[[search-api-scroll-query-param]]
`scroll`::
(Optional, <<time-units,time value>>)
Period to retain the <<scroll-search-context,search context>> for scrolling. See
<<scroll-search-results>>.
+
By default, this value cannot exceed `1d` (24 hours). You can change
this limit using the `search.max_keep_alive` cluster-level setting.

[[search-type]]
`search_type`::
(Optional, string)
How {wikipedia}/Tf–idf[distributed term frequencies] are calculated for
<<relevance-scores,relevance scoring>>.
+
.Valid values for `search_type`
[%collapsible%open]
====
`query_then_fetch`::
(Default)
Distributed term frequencies are calculated locally for each shard running the
search. We recommend this option for faster searches with potentially less
accurate scoring.

[[dfs-query-then-fetch]]
`dfs_query_then_fetch`::
Distributed term frequencies are calculated globally, using information gathered
from all shards running the search. While this option increases the accuracy of
scoring, it adds a round-trip to each shard, which can result in slower
searches.
====

`seq_no_primary_term`::
(Optional, boolean) If `true`, returns sequence number and primary term of the
last modification of each hit. See <<optimistic-concurrency-control>>.

`size`::
(Optional, integer) Defines the number of hits to return. Defaults to `10`.
+
--
By default, you cannot page through more than 10,000 documents using the `from`
and `size` parameters. This limit is set using the
<<index-max-result-window,`index.max_result_window`>> index setting.

Deep paging or requesting many results at once can result in slow searches.
Results are sorted before being returned. Because search requests usually span
multiple shards, each shard must generate its own sorted results. These separate
results must then be combined and sorted to ensure that the overall order is
correct.

As an alternative to deep paging, we recommend using
<<scroll-search-results,scroll>> or the
<<search-after,`search_after`>> parameter.

If the <<search-api-scroll-query-param,`scroll` parameter>> is specified, this
value cannot be `0`.
--

`sort`::
(Optional, string) A comma-separated list of <field>:<direction> pairs.

`_source`::
(Optional)
Indicates which <<mapping-source-field,source fields>> are returned for matching
documents. These fields are returned in the `hits._source` property of
the search response. Defaults to `true`.
+
.Valid values for `_source`
[%collapsible%open]
====
`true`::
(boolean)
The entire document source is returned.

`false`::
(boolean)
The document source is not returned.

`<string>`::
(string)
Comma-separated list of source fields to return.
Wildcard (`*`) patterns are supported.
====

include::{es-repo-dir}/rest-api/common-parms.asciidoc[tag=source_excludes]

include::{es-repo-dir}/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.
+
If this field is specified, the `_source` parameter defaults to `false`. You can
pass `_source: true` to return both source fields and
stored fields in the search 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::{es-repo-dir}/rest-api/common-parms.asciidoc[tag=terminate_after]
+
Defaults to `0`, which does not terminate query execution early.

`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.

`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`.

[role="child_attributes"]
[[search-search-api-request-body]]
==== {api-request-body-title}

[[search-docvalue-fields-param]]
`docvalue_fields`::
(Optional, array of strings and objects)
Array of wildcard (`*`) patterns. The request returns doc values for field names
matching these patterns in the `hits.fields` property of the response.
+
You can specify items in the array as a string or object.
See <<docvalue-fields>>.
+
.Properties of `docvalue_fields` objects
[%collapsible%open]
====
`field`::
(Required, string)
Wildcard pattern. The request returns doc values for field names matching this
pattern.

`format`::
(Optional, string)
Format in which the doc values are returned.
+
For <<date,date fields>>, you can specify a  date <<mapping-date-format,date
`format`>>. For <<number,numeric fields>> fields, you can specify a
https://docs.oracle.com/javase/8/docs/api/java/text/DecimalFormat.html[DecimalFormat
pattern].
+
For other field data types, this parameter is not supported.
====

[[request-body-search-explain]]
`explain`::
(Optional, boolean) If `true`, returns detailed information about score
computation as part of a hit. Defaults to `false`.

include::{es-repo-dir}/rest-api/common-parms.asciidoc[tag=from]
+
--
By default, you cannot page through more than 10,000 documents using the `from`
and `size` parameters. This limit is set using the
<<index-max-result-window,`index.max_result_window`>> index setting.

Deep paging or requesting many results at once can result in slow searches.
Results are sorted before being returned. Because search requests usually span
multiple shards, each shard must generate its own sorted results. These separate
results must then be combined and sorted to ensure that the overall order is
correct.

As an alternative to deep paging, we recommend using
<<scroll-search-results,scroll>> or the
<<search-after,`search_after`>> parameter.
--

`indices_boost`::
(Optional, array of objects)
Boosts the <<relevance-scores,`_score`>> of documents from specified indices.
+
.Properties of `indices_boost` objects
[%collapsible%open]
====
`<index>: <boost-value>`::
(Required, float)
`<index>` is the name of the index or index alias. Wildcard (`*`) expressions
are supported.
+
`<boost-value>` is the factor by which scores are multiplied.
+
A boost value greater than `1.0` increases the score. A boost value between
`0` and `1.0` decreases the score. 
====

[[search-api-min-score]]
`min_score`::
(Optional, float)
Minimum <<relevance-scores,`_score`>> for matching documents. Documents with a
lower `_score` are not included in the search results.

[[request-body-search-query]]
`query`::
(Optional, <<query-dsl,query object>>) Defines the search definition using the
<<query-dsl,Query DSL>>.

[[request-body-search-seq-no-primary-term]]
`seq_no_primary_term`::
(Optional, boolean) If `true`, returns sequence number and primary term of the
last modification of each hit. See <<optimistic-concurrency-control>>.

`size`:: 
(Optional, integer) The number of hits to return. Defaults to `10`.
+
--
By default, you cannot page through more than 10,000 documents using the `from`
and `size` parameters. This limit is set using the
<<index-max-result-window,`index.max_result_window`>> index setting.

Deep paging or requesting many results at once can result in slow searches.
Results are sorted before being returned. Because search requests usually span
multiple shards, each shard must generate its own sorted results. These separate
results must then be combined and sorted to ensure that the overall order is
correct.

As an alternative to deep paging, we recommend using
<<scroll-search-results,scroll>> or the
<<search-after,`search_after`>> parameter.

If the <<search-api-scroll-query-param,`scroll` parameter>> is specified, this
value cannot be `0`.
--

`_source`::
(Optional)
Indicates which <<mapping-source-field,source fields>> are returned for matching
documents. These fields are returned in the `hits._source` property of
the search response. Defaults to `true`.
+
.Valid values for `_source`
[%collapsible%open]
====
`true`::
(boolean)
The entire document source is returned.

`false`::
(boolean)
The document source is not returned.

`<wildcard_pattern>`::
(string or array of strings)
Wildcard (`*`) pattern or array of patterns containing source fields to return.

`<object>`::
(object)
Object containing a list of source fields to include or exclude.
+
.Properties for `<object>`
[%collapsible%open]
=====
`excludes`::
(string or array of strings)
Wildcard (`*`) pattern or array of patterns containing source fields to exclude
from the response.
+
You can also use this property to exclude fields from the subset specified in
`includes` property.

`includes`::
(string or array of strings)
Wildcard (`*`) pattern or array of patterns containing source fields to return.
+
If this property is specified, only these source fields are returned. You can
exclude fields from this subset using the `excludes` property.
=====
====

[[stats-groups]]
`stats`::
(Optional, array of strings)
Stats groups to associate with the search. Each group maintains a statistics
aggregation for its associated searches. You can retrieve these stats using the
<<indices-stats,indices stats API>>.

include::{es-repo-dir}/rest-api/common-parms.asciidoc[tag=terminate_after]
+
Defaults to `0`, which does not terminate query execution early.

`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.

[[request-body-search-version]]
`version`::
(Optional, boolean)
If `true`, returns document version as part of a hit. Defaults to `false`.


[role="child_attributes"]
[[search-api-response-body]]
==== {api-response-body-title}

`_scroll_id`::
(string)
Identifier for the search and its <<scroll-search-context,search context>>.
+
You can use this scroll ID with the <<scroll-api,scroll API>> to retrieve the
next batch of search results for the request. See
<<scroll-search-results>>.
+
This parameter is only returned if the <<search-api-scroll-query-param,`scroll`
query parameter>> is specified in the request.

`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.
+
You can use the `_source` parameter to exclude this property from the response
or specify which source fields to return.

`fields`::
+
--
(object)
Contains field values for the documents. These fields must be specified in the
request using one or more of the following request parameters:

* <<search-docvalue-fields-param,`docvalue_fields`>>
* <<script-fields,`script_fields`>>
* <<stored-fields,`stored_fields`>>

This property is returned only if one or more of these parameters are set.
--
+
.Properties of `fields`
[%collapsible%open]
======
`<field>`::
(array)
Key is the field name. Value is the value for the field.
======
=====
====

[[search-search-api-example]]
==== {api-examples-title}

[source,console]
----
GET /my-index-000001/_search
{
  "query": {
    "term": {
      "user.id": "kimchy"
    }
  }
}
----
// TEST[setup:my_index]

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": "my-index-000001",
        "_type" : "_doc",
        "_id": "0",
        "_score": 1.3862942,
        "_source": {
          "@timestamp": "2099-11-15T14:12:12",
          "http": {
            "request": {
              "method": "get"
            },
            "response": {
              "status_code": 200,
              "bytes": 1070000
            },
            "version": "1.1"
          },
          "source": {
            "ip": "127.0.0.1"
          },
          "message": "GET /search HTTP/1.1 200 1070000",
          "user": {
            "id": "kimchy"
          }
        }
      }
    ]
  }
}
----
// TESTRESPONSE[s/"took": 5/"took": $body.took/]