--
:api: force-merge
:request: ForceMergeRequest
:response: ForceMergeResponse
--

[id="{upid}-{api}"]
=== Force Merge API

[id="{upid}-{api}-request"]
==== Force merge Request

A +{request}+ can be applied to one or more indices, or even on `_all` the indices:

["source","java",subs="attributes,callouts,macros"]
--------------------------------------------------
include-tagged::{doc-tests-file}[{api}-request]
--------------------------------------------------
<1> Force merge one index
<2> Force merge multiple indices
<3> Force merge all the indices

==== Optional arguments

["source","java",subs="attributes,callouts,macros"]
--------------------------------------------------
include-tagged::{doc-tests-file}[{api}-request-indicesOptions]
--------------------------------------------------
<1> Setting `IndicesOptions` controls how unavailable indices are resolved and
how wildcard expressions are expanded

["source","java",subs="attributes,callouts,macros"]
--------------------------------------------------
include-tagged::{doc-tests-file}[{api}-request-segments-num]
--------------------------------------------------
<1> Set `max_num_segments` to control the number of segments to merge down to.

["source","java",subs="attributes,callouts,macros"]
--------------------------------------------------
include-tagged::{doc-tests-file}[{api}-request-only-expunge-deletes]
--------------------------------------------------
<1> Set the `only_expunge_deletes` flag to `true`

["source","java",subs="attributes,callouts,macros"]
--------------------------------------------------
include-tagged::{doc-tests-file}[{api}-request-flush]
--------------------------------------------------
<1> Set the `flush` flag to `true`

include::../execution.asciidoc[]

[id="{upid}-{api}-response"]
==== Force Merge Response

The returned +{response}+ allows to retrieve information about the
executed operation as follows:

["source","java",subs="attributes,callouts,macros"]
--------------------------------------------------
include-tagged::{doc-tests-file}[{api}-response]
--------------------------------------------------
<1> Total number of shards hit by the force merge request
<2> Number of shards where the force merge has succeeded
<3> Number of shards where the force merge has failed
<4> A list of failures if the operation failed on one or more shards

By default, if the indices were not found, an `ElasticsearchException` will be thrown:

["source","java",subs="attributes,callouts,macros"]
--------------------------------------------------
include-tagged::{doc-tests-file}[{api}-notfound]
--------------------------------------------------
<1> Do something if the indices to be force merged were not found