OpenSearch/docs/reference/search/search.asciidoc

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[[search-search]]
=== Search
Returns search hits that match the query defined in the request.
[source,console]
----
GET /twitter/_search?q=tag:wow
----
// TEST[setup:twitter]
[[search-search-api-request]]
==== {api-request-title}
`GET /<index>/_search`
`POST /<index>/_search`
`GET /_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. The query can either be provided using a simple
<<search-uri-request,query string as a parameter>>, or using a
<<search-request-body,request body>>.
[[search-partial-responses]]
===== Partial responses
To ensure fast responses, the search API will respond with partial results if
one or more shards fail. See <<shard-failures, Shard failures>> for more
information.
[[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`.
`allow_partial_search_results`::
(Optional, boolean) Indicates if an error should be returned if there is a
partial search failure or timeout. Defaults to `true`.
`analyzer`::
(Optional, string) Defines the analyzer to use for the query string.
`analyze_wildcard`::
(Optional, boolean) If `true`, wildcard and prefix queries will also be
analyzed. Defaults 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`::
(Optional, boolean) Indicates whether network round-trips should be minimized
as part of cross-cluster search requests execution. Defaults to `true`.
`default_operator`::
(Optional, string) The default operator for query string query (AND or OR).
Defaults to `OR`.
`df`::
(Optional, string) Defines the field to use as default where no field prefix
is given in the query string.
`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`.
`from`::
(Optional, integer) Defines the starting offset. Defaults to `0`.
`ignore_throttled`::
(Optional, boolean) If `true`, concrete, expanded or aliased indices will be
ignored when throttled. Defaults to `false`.
include::{docdir}/rest-api/common-parms.asciidoc[tag=index-ignore-unavailable]
`lenient`::
(Optional, boolean) If `true`, format-based query failures (such as
providing text to a numeric field) will be ignored. Defaults to `false`.
`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.
`q`::
(Optional, string) Query in the Lucene query string syntax.
`request_cache`::
(Optional, boolean) If `true`, request cache will be used for this request.
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.
`search_type`::
(Optional, string) Defines the type of the search operation. Available
options:
* `query_then_fetch`
* `dfs_query_then_fetch`
`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`.
`sort`::
(Optional, string) A comma-separated list of <field>:<direction> pairs.
`_source`::
(Optional, string) True or false to return the `_source` field or not, or a
list of fields to return.
`_source_excludes`::
(Optional, string) A list of fields to exclude from the returned `_source`
field.
`_source_includes`::
(Optional, string) A list of fields to extract and return from the `_source`
field.
`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.
`suggest_field`::
(Optional, string) Specifies which field to use for suggestions.
`suggest_mode`::
(Optional, string) Specifies suggest mode. Defaults to `missing`. Available
options:
* `always`
* `missing`
* `popular`
`suggest_size`::
(Optional, integer) Defines how many suggestions to return in response.
`suggest_text`::
(Optional, string) The source text for which the suggestions should be
returned.
`terminate_after`::
(Optional, integer) The maximum number of documents to collect for each shard,
upon reaching which the query execution will terminate early.
include::{docdir}/rest-api/common-parms.asciidoc[tag=timeout]
`track_scores`::
(Optional, boolean) If `true`, then calculates and returns scores even if they
are not used for sorting.
`track_total_hits`::
(Optional, boolean) Indicates if the number of documents that match the query
should be tracked.
`typed_keys`::
(Optional, boolean) Specifies whether aggregation and suggester names should
be prefixed by their respective types in the response.
`version`::
(Optional, boolean) If `true`, returns document version as part of a hit.
[[search-search-api-request-body]]
==== {api-request-body-title}
`query`::
(Optional, <<query-dsl,query object>>) Defines the search definition using the
<<query-dsl,Query DSL>>.
[[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)
Object containing a count of shards used for the request.
Returned parameters include:
`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.
Returned parameters include:
`total`::
(Object)
Metadata about the number of returned documents.
Returned parameters include:
+
* `value`: Total number of returned documents.
* `relation`: Indicates whether the number of returned documents in the `value`
parameter is accurate or a lower bound. Returned values are:
** `eq`: Accurate
** `gte`: Lower bound, including returned documents
`max_score`::
(Float)
Highest returned document `_score`.
+
The `_score` parameter is a 32-bit floating point number
used to determine the relevance of the returned document.
+
This parameter value is `null` for requests
that do not sort by `_score`.
`hits`::
(Array of objects)
Array of returned document objects.
Returned parameters include:
+
* `_index`: Name of the index containing the returned document.
* `_type`: Document type.
deprecated:[7.0.0, Types are deprecated and are in the process of being removed. See <<removal-of-types>>.]
* `_id`: Unique identifier for the returned document.
This ID is only unique within the returned index.
* `_score`: Positive 32-bit floating point number used to determine the
relevance of the returned document.
* `_source`: Object containing the original JSON body
passed for the document at index time.
--
[[search-search-api-example]]
==== {api-examples-title}
[[search-api-specific-ex]]
===== Search a specific index
[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
[source,console]
----
GET /kimchy,elasticsearch/_search?q=user:kimchy
----
// TEST[s/^/PUT kimchy\nPUT elasticsearch\n/]
[[search-api-all-ex]]
===== Search all indices
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]