FirebaseFirestore Framework Reference

WindowFunction

public class WindowFunction : AggregateBridgeWrapper, @unchecked Sendable

[Public Preview] A function that is evaluated over a window of documents in an addWindowFields stage.

Create a WindowFunction with a dedicated window function such as Rank(), or by calling over(_:) on an AggregateFunction.

Warning

Window Functions SDK features are in preview until the backend feature launches. Look for the launch announcement at: https://docs.cloud.google.com/firestore/docs/release-notes


                    
                    
                    as(_:)

Creates an AliasedWindowFunction from this window function.

Swift

public func `as`(_ name: String) -> AliasedWindowFunction


                                name

The name of the output field that will contain the result.

An AliasedWindowFunction with the given alias.

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Last updated 2026-11-13 UTC.