@PublicEvolving public abstract class GroupWindow extends Object
Group windows group rows based on time or row-count intervals and is therefore essentially a special type of groupBy. Just like groupBy, group windows allow to compute aggregates on groups of elements.
Infinite streaming tables can only be grouped into time or row intervals. Hence window grouping is required to apply aggregations on streaming tables.
For finite batch tables, group windows provide shortcuts for time-based groupBy.
|Modifier and Type||Method and Description|
public Expression getAlias()
public Expression getTimeField()
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