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AggregateStage

class AggregateStage : Stage

kotlin.Any
↳	com.google.firebase.firestore.pipeline.Stage
	↳	com.google.firebase.firestore.pipeline.AggregateStage

Performs optionally grouped aggregation operations on the documents from previous stages.

This stage allows you to calculate aggregate values over a set of documents, optionally grouped by one or more fields or functions. You can specify:

Grouping Fields or Expressions: One or more fields or functions to group the documents by. For each distinct combination of values in these fields, a separate group is created. If no grouping fields are provided, a single group containing all documents is used. Not specifying groups is the same as putting the entire inputs into one group.
AggregateFunctions: One or more accumulation operations to perform within each group. These are defined using AliasedAggregate expressions, which are typically created by calling AggregateFunction.alias on AggregateFunction instances. Each aggregation calculates a value (e.g., sum, average, count) based on the documents within its group.

Summary

Public companion functions
`AggregateStage`	`withAccumulators( accumulator: AliasedAggregate, vararg additionalAccumulators: AliasedAggregate )` Create `AggregateStage` with one or more accumulators.

Public functions
`open operator Boolean`	`equals(other: Any?)`
`open Int`	`hashCode()`
`AggregateStage`	`withGroups(group: Selectable, vararg additionalGroups: Any)` Add one or more groups to `AggregateStage`
`AggregateStage`	`withGroups(groupField: String, vararg additionalGroups: Any)` Add one or more groups to `AggregateStage`

Inherited functions

From com.google.firebase.firestore.pipeline.Stage

`AggregateStage`	`withOption(key: String, value: <Error class: unknown class>)`
`AggregateStage`	`withOption(key: String, value: Boolean)` Specify named `Boolean` parameter
`AggregateStage`	`withOption(key: String, value: Double)` Specify named `Double` parameter
`AggregateStage`	`withOption(key: String, value: Field)` Specify named `Field` parameter
`AggregateStage`	`withOption(key: String, value: Long)` Specify named `Long` parameter
`AggregateStage`	`withOption(key: String, value: String)` Specify named `String` parameter

Public companion functions

withAccumulators

fun withAccumulators(
    accumulator: AliasedAggregate,
    vararg additionalAccumulators: AliasedAggregate
): AggregateStage

Create AggregateStage with one or more accumulators.

Parameters
`accumulator: AliasedAggregate`	The first `AliasedAggregate` expression, wrapping an `AggregateFunction` with an alias for the accumulated results.
`vararg additionalAccumulators: AliasedAggregate`	The `AliasedAggregate` expressions, each wrapping an `AggregateFunction` with an alias for the accumulated results.

Returns
`AggregateStage`	`AggregateStage` with specified accumulators.

Public functions

equals

open operator fun equals(other: Any?): Boolean

hashCode

open fun hashCode(): Int

withGroups

fun withGroups(group: Selectable, vararg additionalGroups: Any): AggregateStage

Add one or more groups to AggregateStage

Parameters
`group: Selectable`	The `Selectable` expression to consider when determining group value combinations.
`vararg additionalGroups: Any`	The `Selectable` expressions to consider when determining group value combinations or `String`s representing field names.

Returns
`AggregateStage`	`AggregateStage` with specified groups.

withGroups

fun withGroups(groupField: String, vararg additionalGroups: Any): AggregateStage

Add one or more groups to AggregateStage

Parameters
`groupField: String`	The `String` representing field name.
`vararg additionalGroups: Any`	The `Selectable` expressions to consider when determining group value combinations or `String`s representing field names.

Returns
`AggregateStage`	`AggregateStage` with specified groups.