[FLINK-3473] Add partial aggregate support in Flink

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Won't Fix
• Component/s: Table SQL / Legacy Planner
• Labels: auto-deprioritized-major auto-unassigned
• Assignee: Unassigned
• Reporter: Chengxiang Li
• Created: 23/Feb/16 07:38
• Updated: 05/Jul/21 13:19
• Resolved: 05/Jul/21 13:19

Description

For decomposable aggregate function, partial aggregate is more efficient as it significantly reduce the network traffic during shuffle and parallelize part of the aggregate calculation. This is an umbrella task for partial aggregate.

Sub-Tasks

• Partial aggregate interface design and sort-based implementation: Closed
• Support hash-based partial aggregate: Closed
• Risk of data overflow while use sum/count to calculate AVG value: Closed