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https://issues.apache.org/jira/browse/FLINK-4937?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15662466#comment-15662466
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sunjincheng edited comment on FLINK-4937 at 11/14/16 9:35 AM:
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I had thought about calling transformToAggregateFunctions explicitly before
createOperatorFunctionsForAggregates in DataSetAggregate. But in
DataSetAggregate will not use transformToAggregateFunctions's return results In
addition to calling createOperatorFunctionsForAggregates. so,i hope overload
createOperatorFunctionsForAggregates. What do you think [~fhueske]?
was (Author: sunjincheng121):
I had thought about calling transformToAggregateFunctions explicitly before
createOperatorFunctionsForAggregates in DataSetAggregate. But in
DataSetAggregate will not use transformToAggregateFunctions's return results In
addition to calling createOperatorFunctionsForAggregates. so,i hope overload
createOperatorFunctionsForAggregates. What do you think @fhueske ?
> Add incremental group window aggregation for streaming Table API
> ----------------------------------------------------------------
>
> Key: FLINK-4937
> URL: https://issues.apache.org/jira/browse/FLINK-4937
> Project: Flink
> Issue Type: Sub-task
> Components: Table API & SQL
> Affects Versions: 1.2.0
> Reporter: Fabian Hueske
> Assignee: sunjincheng
>
> Group-window aggregates for streaming tables are currently not done in an
> incremental fashion. This means that the window collects all records and
> performs the aggregation when the window is closed instead of eagerly
> updating a partial aggregate for every added record. Since records are
> buffered, non-incremental aggregation requires more storage space than
> incremental aggregation.
> The DataStream API which is used under the hood of the streaming Table API
> features [incremental
> aggregation|https://ci.apache.org/projects/flink/flink-docs-release-1.2/dev/windows.html#windowfunction-with-incremental-aggregation]
> using a {{ReduceFunction}}.
> We should add support for incremental aggregation in group-windows.
> This is a follow-up task of FLINK-4691.
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