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Metric aggregation reduce context | Painless Scripting Language [8.19] | Elastic
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Metric aggregation reduce context

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Use a Painless script to reduce values to produce the result of a scripted metric aggregation. A reduce script is run once on the coordinating node following a combine script (or a map script if no combine script is specified) and is optional as part of a full metric aggregation.

Variables

params (Map, read-only)
User-defined parameters passed in as part of the query.
states (Map)
Map with values available from the prior combine script (or a map script if no combine script is specified).

Return

List, Map, String, or primitive
A value used as the result.

API

The standard Painless API is available.