50 lines
1.5 KiB
Plaintext
50 lines
1.5 KiB
Plaintext
[[search-request-preference]]
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=== Preference
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Controls a `preference` of which shard copies on which to execute the
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search. By default, the operation is randomized among the available shard
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copies, unless allocation awareness is used.
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The `preference` is a query string parameter which can be set to:
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[horizontal]
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`_local`::
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The operation will prefer to be executed on a local
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allocated shard if possible.
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`_prefer_nodes:abc,xyz`::
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Prefers execution on the nodes with the provided
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node ids (`abc` or `xyz` in this case) if applicable.
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`_shards:2,3`::
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Restricts the operation to the specified shards. (`2`
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and `3` in this case). This preference can be combined with other
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preferences but it has to appear first: `_shards:2,3|_local`
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`_only_nodes`::
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Restricts the operation to nodes specified in <<cluster,node specification>>
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Custom (string) value::
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A custom value will be used to guarantee that
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the same shards will be used for the same custom value. This can help
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with "jumping values" when hitting different shards in different refresh
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states. A sample value can be something like the web session id, or the
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user name.
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For instance, use the user's session ID to ensure consistent ordering of results
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for the user:
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[source,js]
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------------------------------------------------
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GET /_search?preference=xyzabc123
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{
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"query": {
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"match": {
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"title": "elasticsearch"
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}
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}
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}
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------------------------------------------------
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// CONSOLE
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