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AggregateWindowFunction — Declarative Window Aggregate Function Expressions

AggregateWindowFunction is the <> of the DeclarativeAggregate contract for <> that are also WindowFunction expressions.

[[contract]] [source, scala]

package org.apache.spark.sql.catalyst.expressions

abstract class AggregateWindowFunction extends DeclarativeAggregate with WindowFunction { self: Product => // No required properties (vals and methods) that have no implementation }

[[dataType]] AggregateWindowFunction uses IntegerType as the data type of the result of evaluating itself.

[[nullable]] AggregateWindowFunction is nullable by default.

[[frame]] As a <> expression, AggregateWindowFunction uses a SpecifiedWindowFrame (with the RowFrame frame type, the UnboundedPreceding lower and the CurrentRow upper frame boundaries) as the <>.

[[mergeExpressions]] AggregateWindowFunction is a <> expression that does not support <> (two aggregation buffers together) and throws an UnsupportedOperationException whenever requested for it.

Window Functions do not support merging.

[[extensions]] .AggregateWindowFunctions (Direct Implementations) [cols="1,2",options="header",width="100%"] |=== | AggregateWindowFunction | Description

| <> | [[RankLike]]

| <> | [[RowNumberLike]]

| <> | [[SizeBasedWindowFunction]] Window functions that require the size of the current window for calculation |===

Last update: 2020-10-21